--- /dev/null
+/*
+ * copyright (c) 2001 Fabrice Bellard
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVFORMAT_AVFORMAT_H
+#define AVFORMAT_AVFORMAT_H
+
+/**
+ * @file
+ * @ingroup libavf
+ * Main libavformat public API header
+ */
+
+/**
+ * @defgroup libavf I/O and Muxing/Demuxing Library
+ * @{
+ *
+ * Libavformat (lavf) is a library for dealing with various media container
+ * formats. Its main two purposes are demuxing - i.e. splitting a media file
+ * into component streams, and the reverse process of muxing - writing supplied
+ * data in a specified container format. It also has an @ref lavf_io
+ * "I/O module" which supports a number of protocols for accessing the data (e.g.
+ * file, tcp, http and others). Before using lavf, you need to call
+ * av_register_all() to register all compiled muxers, demuxers and protocols.
+ * Unless you are absolutely sure you won't use libavformat's network
+ * capabilities, you should also call avformat_network_init().
+ *
+ * A supported input format is described by an AVInputFormat struct, conversely
+ * an output format is described by AVOutputFormat. You can iterate over all
+ * registered input/output formats using the av_iformat_next() /
+ * av_oformat_next() functions. The protocols layer is not part of the public
+ * API, so you can only get the names of supported protocols with the
+ * avio_enum_protocols() function.
+ *
+ * Main lavf structure used for both muxing and demuxing is AVFormatContext,
+ * which exports all information about the file being read or written. As with
+ * most Libavformat structures, its size is not part of public ABI, so it cannot be
+ * allocated on stack or directly with av_malloc(). To create an
+ * AVFormatContext, use avformat_alloc_context() (some functions, like
+ * avformat_open_input() might do that for you).
+ *
+ * Most importantly an AVFormatContext contains:
+ * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat
+ * "output" format. It is either autodetected or set by user for input;
+ * always set by user for output.
+ * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all
+ * elementary streams stored in the file. AVStreams are typically referred to
+ * using their index in this array.
+ * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or
+ * set by user for input, always set by user for output (unless you are dealing
+ * with an AVFMT_NOFILE format).
+ *
+ * @section lavf_options Passing options to (de)muxers
+ * It is possible to configure lavf muxers and demuxers using the @ref avoptions
+ * mechanism. Generic (format-independent) libavformat options are provided by
+ * AVFormatContext, they can be examined from a user program by calling
+ * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass
+ * from avformat_get_class()). Private (format-specific) options are provided by
+ * AVFormatContext.priv_data if and only if AVInputFormat.priv_class /
+ * AVOutputFormat.priv_class of the corresponding format struct is non-NULL.
+ * Further options may be provided by the @ref AVFormatContext.pb "I/O context",
+ * if its AVClass is non-NULL, and the protocols layer. See the discussion on
+ * nesting in @ref avoptions documentation to learn how to access those.
+ *
+ * @section urls
+ * URL strings in libavformat are made of a scheme/protocol, a ':', and a
+ * scheme specific string. URLs without a scheme and ':' used for local files
+ * are supported but deprecated. "file:" should be used for local files.
+ *
+ * It is important that the scheme string is not taken from untrusted
+ * sources without checks.
+ *
+ * Note that some schemes/protocols are quite powerful, allowing access to
+ * both local and remote files, parts of them, concatenations of them, local
+ * audio and video devices and so on.
+ *
+ * @defgroup lavf_decoding Demuxing
+ * @{
+ * Demuxers read a media file and split it into chunks of data (@em packets). A
+ * @ref AVPacket "packet" contains one or more encoded frames which belongs to a
+ * single elementary stream. In the lavf API this process is represented by the
+ * avformat_open_input() function for opening a file, av_read_frame() for
+ * reading a single packet and finally avformat_close_input(), which does the
+ * cleanup.
+ *
+ * @section lavf_decoding_open Opening a media file
+ * The minimum information required to open a file is its URL, which
+ * is passed to avformat_open_input(), as in the following code:
+ * @code
+ * const char *url = "file:in.mp3";
+ * AVFormatContext *s = NULL;
+ * int ret = avformat_open_input(&s, url, NULL, NULL);
+ * if (ret < 0)
+ * abort();
+ * @endcode
+ * The above code attempts to allocate an AVFormatContext, open the
+ * specified file (autodetecting the format) and read the header, exporting the
+ * information stored there into s. Some formats do not have a header or do not
+ * store enough information there, so it is recommended that you call the
+ * avformat_find_stream_info() function which tries to read and decode a few
+ * frames to find missing information.
+ *
+ * In some cases you might want to preallocate an AVFormatContext yourself with
+ * avformat_alloc_context() and do some tweaking on it before passing it to
+ * avformat_open_input(). One such case is when you want to use custom functions
+ * for reading input data instead of lavf internal I/O layer.
+ * To do that, create your own AVIOContext with avio_alloc_context(), passing
+ * your reading callbacks to it. Then set the @em pb field of your
+ * AVFormatContext to newly created AVIOContext.
+ *
+ * Since the format of the opened file is in general not known until after
+ * avformat_open_input() has returned, it is not possible to set demuxer private
+ * options on a preallocated context. Instead, the options should be passed to
+ * avformat_open_input() wrapped in an AVDictionary:
+ * @code
+ * AVDictionary *options = NULL;
+ * av_dict_set(&options, "video_size", "640x480", 0);
+ * av_dict_set(&options, "pixel_format", "rgb24", 0);
+ *
+ * if (avformat_open_input(&s, url, NULL, &options) < 0)
+ * abort();
+ * av_dict_free(&options);
+ * @endcode
+ * This code passes the private options 'video_size' and 'pixel_format' to the
+ * demuxer. They would be necessary for e.g. the rawvideo demuxer, since it
+ * cannot know how to interpret raw video data otherwise. If the format turns
+ * out to be something different than raw video, those options will not be
+ * recognized by the demuxer and therefore will not be applied. Such unrecognized
+ * options are then returned in the options dictionary (recognized options are
+ * consumed). The calling program can handle such unrecognized options as it
+ * wishes, e.g.
+ * @code
+ * AVDictionaryEntry *e;
+ * if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
+ * fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key);
+ * abort();
+ * }
+ * @endcode
+ *
+ * After you have finished reading the file, you must close it with
+ * avformat_close_input(). It will free everything associated with the file.
+ *
+ * @section lavf_decoding_read Reading from an opened file
+ * Reading data from an opened AVFormatContext is done by repeatedly calling
+ * av_read_frame() on it. Each call, if successful, will return an AVPacket
+ * containing encoded data for one AVStream, identified by
+ * AVPacket.stream_index. This packet may be passed straight into the libavcodec
+ * decoding functions avcodec_decode_video2(), avcodec_decode_audio4() or
+ * avcodec_decode_subtitle2() if the caller wishes to decode the data.
+ *
+ * AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be
+ * set if known. They may also be unset (i.e. AV_NOPTS_VALUE for
+ * pts/dts, 0 for duration) if the stream does not provide them. The timing
+ * information will be in AVStream.time_base units, i.e. it has to be
+ * multiplied by the timebase to convert them to seconds.
+ *
+ * If AVPacket.buf is set on the returned packet, then the packet is
+ * allocated dynamically and the user may keep it indefinitely.
+ * Otherwise, if AVPacket.buf is NULL, the packet data is backed by a
+ * static storage somewhere inside the demuxer and the packet is only valid
+ * until the next av_read_frame() call or closing the file. If the caller
+ * requires a longer lifetime, av_dup_packet() will make an av_malloc()ed copy
+ * of it.
+ * In both cases, the packet must be freed with av_packet_unref() when it is no
+ * longer needed.
+ *
+ * @section lavf_decoding_seek Seeking
+ * @}
+ *
+ * @defgroup lavf_encoding Muxing
+ * @{
+ * Muxers take encoded data in the form of @ref AVPacket "AVPackets" and write
+ * it into files or other output bytestreams in the specified container format.
+ *
+ * The main API functions for muxing are avformat_write_header() for writing the
+ * file header, av_write_frame() / av_interleaved_write_frame() for writing the
+ * packets and av_write_trailer() for finalizing the file.
+ *
+ * At the beginning of the muxing process, the caller must first call
+ * avformat_alloc_context() to create a muxing context. The caller then sets up
+ * the muxer by filling the various fields in this context:
+ *
+ * - The @ref AVFormatContext.oformat "oformat" field must be set to select the
+ * muxer that will be used.
+ * - Unless the format is of the AVFMT_NOFILE type, the @ref AVFormatContext.pb
+ * "pb" field must be set to an opened IO context, either returned from
+ * avio_open2() or a custom one.
+ * - Unless the format is of the AVFMT_NOSTREAMS type, at least one stream must
+ * be created with the avformat_new_stream() function. The caller should fill
+ * the @ref AVStream.codec "stream codec context" information, such as the
+ * codec @ref AVCodecContext.codec_type "type", @ref AVCodecContext.codec_id
+ * "id" and other parameters (e.g. width / height, the pixel or sample format,
+ * etc.) as known. The @ref AVStream.time_base "stream timebase" should
+ * be set to the timebase that the caller desires to use for this stream (note
+ * that the timebase actually used by the muxer can be different, as will be
+ * described later).
+ * - It is advised to manually initialize only the relevant fields in
+ * AVCodecContext, rather than using @ref avcodec_copy_context() during
+ * remuxing: there is no guarantee that the codec context values remain valid
+ * for both input and output format contexts.
+ * - The caller may fill in additional information, such as @ref
+ * AVFormatContext.metadata "global" or @ref AVStream.metadata "per-stream"
+ * metadata, @ref AVFormatContext.chapters "chapters", @ref
+ * AVFormatContext.programs "programs", etc. as described in the
+ * AVFormatContext documentation. Whether such information will actually be
+ * stored in the output depends on what the container format and the muxer
+ * support.
+ *
+ * When the muxing context is fully set up, the caller must call
+ * avformat_write_header() to initialize the muxer internals and write the file
+ * header. Whether anything actually is written to the IO context at this step
+ * depends on the muxer, but this function must always be called. Any muxer
+ * private options must be passed in the options parameter to this function.
+ *
+ * The data is then sent to the muxer by repeatedly calling av_write_frame() or
+ * av_interleaved_write_frame() (consult those functions' documentation for
+ * discussion on the difference between them; only one of them may be used with
+ * a single muxing context, they should not be mixed). Do note that the timing
+ * information on the packets sent to the muxer must be in the corresponding
+ * AVStream's timebase. That timebase is set by the muxer (in the
+ * avformat_write_header() step) and may be different from the timebase
+ * requested by the caller.
+ *
+ * Once all the data has been written, the caller must call av_write_trailer()
+ * to flush any buffered packets and finalize the output file, then close the IO
+ * context (if any) and finally free the muxing context with
+ * avformat_free_context().
+ * @}
+ *
+ * @defgroup lavf_io I/O Read/Write
+ * @{
+ * @section lavf_io_dirlist Directory listing
+ * The directory listing API makes it possible to list files on remote servers.
+ *
+ * Some of possible use cases:
+ * - an "open file" dialog to choose files from a remote location,
+ * - a recursive media finder providing a player with an ability to play all
+ * files from a given directory.
+ *
+ * @subsection lavf_io_dirlist_open Opening a directory
+ * At first, a directory needs to be opened by calling avio_open_dir()
+ * supplied with a URL and, optionally, ::AVDictionary containing
+ * protocol-specific parameters. The function returns zero or positive
+ * integer and allocates AVIODirContext on success.
+ *
+ * @code
+ * AVIODirContext *ctx = NULL;
+ * if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) {
+ * fprintf(stderr, "Cannot open directory.\n");
+ * abort();
+ * }
+ * @endcode
+ *
+ * This code tries to open a sample directory using smb protocol without
+ * any additional parameters.
+ *
+ * @subsection lavf_io_dirlist_read Reading entries
+ * Each directory's entry (i.e. file, another directory, anything else
+ * within ::AVIODirEntryType) is represented by AVIODirEntry.
+ * Reading consecutive entries from an opened AVIODirContext is done by
+ * repeatedly calling avio_read_dir() on it. Each call returns zero or
+ * positive integer if successful. Reading can be stopped right after the
+ * NULL entry has been read -- it means there are no entries left to be
+ * read. The following code reads all entries from a directory associated
+ * with ctx and prints their names to standard output.
+ * @code
+ * AVIODirEntry *entry = NULL;
+ * for (;;) {
+ * if (avio_read_dir(ctx, &entry) < 0) {
+ * fprintf(stderr, "Cannot list directory.\n");
+ * abort();
+ * }
+ * if (!entry)
+ * break;
+ * printf("%s\n", entry->name);
+ * avio_free_directory_entry(&entry);
+ * }
+ * @endcode
+ * @}
+ *
+ * @defgroup lavf_codec Demuxers
+ * @{
+ * @defgroup lavf_codec_native Native Demuxers
+ * @{
+ * @}
+ * @defgroup lavf_codec_wrappers External library wrappers
+ * @{
+ * @}
+ * @}
+ * @defgroup lavf_protos I/O Protocols
+ * @{
+ * @}
+ * @defgroup lavf_internal Internal
+ * @{
+ * @}
+ * @}
+ *
+ */
+
+#include <time.h>
+#include <stdio.h> /* FILE */
+#include "libavcodec/avcodec.h"
+#include "libavutil/dict.h"
+#include "libavutil/log.h"
+
+#include "avio.h"
+#include "libavformat/version.h"
+
+struct AVFormatContext;
+
+struct AVDeviceInfoList;
+struct AVDeviceCapabilitiesQuery;
+
+/**
+ * @defgroup metadata_api Public Metadata API
+ * @{
+ * @ingroup libavf
+ * The metadata API allows libavformat to export metadata tags to a client
+ * application when demuxing. Conversely it allows a client application to
+ * set metadata when muxing.
+ *
+ * Metadata is exported or set as pairs of key/value strings in the 'metadata'
+ * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
+ * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg,
+ * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
+ * exported by demuxers isn't checked to be valid UTF-8 in most cases.
+ *
+ * Important concepts to keep in mind:
+ * - Keys are unique; there can never be 2 tags with the same key. This is
+ * also meant semantically, i.e., a demuxer should not knowingly produce
+ * several keys that are literally different but semantically identical.
+ * E.g., key=Author5, key=Author6. In this example, all authors must be
+ * placed in the same tag.
+ * - Metadata is flat, not hierarchical; there are no subtags. If you
+ * want to store, e.g., the email address of the child of producer Alice
+ * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
+ * - Several modifiers can be applied to the tag name. This is done by
+ * appending a dash character ('-') and the modifier name in the order
+ * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
+ * - language -- a tag whose value is localized for a particular language
+ * is appended with the ISO 639-2/B 3-letter language code.
+ * For example: Author-ger=Michael, Author-eng=Mike
+ * The original/default language is in the unqualified "Author" tag.
+ * A demuxer should set a default if it sets any translated tag.
+ * - sorting -- a modified version of a tag that should be used for
+ * sorting will have '-sort' appended. E.g. artist="The Beatles",
+ * artist-sort="Beatles, The".
+ * - Some protocols and demuxers support metadata updates. After a successful
+ * call to av_read_packet(), AVFormatContext.event_flags or AVStream.event_flags
+ * will be updated to indicate if metadata changed. In order to detect metadata
+ * changes on a stream, you need to loop through all streams in the AVFormatContext
+ * and check their individual event_flags.
+ *
+ * - Demuxers attempt to export metadata in a generic format, however tags
+ * with no generic equivalents are left as they are stored in the container.
+ * Follows a list of generic tag names:
+ *
+ @verbatim
+ album -- name of the set this work belongs to
+ album_artist -- main creator of the set/album, if different from artist.
+ e.g. "Various Artists" for compilation albums.
+ artist -- main creator of the work
+ comment -- any additional description of the file.
+ composer -- who composed the work, if different from artist.
+ copyright -- name of copyright holder.
+ creation_time-- date when the file was created, preferably in ISO 8601.
+ date -- date when the work was created, preferably in ISO 8601.
+ disc -- number of a subset, e.g. disc in a multi-disc collection.
+ encoder -- name/settings of the software/hardware that produced the file.
+ encoded_by -- person/group who created the file.
+ filename -- original name of the file.
+ genre -- <self-evident>.
+ language -- main language in which the work is performed, preferably
+ in ISO 639-2 format. Multiple languages can be specified by
+ separating them with commas.
+ performer -- artist who performed the work, if different from artist.
+ E.g for "Also sprach Zarathustra", artist would be "Richard
+ Strauss" and performer "London Philharmonic Orchestra".
+ publisher -- name of the label/publisher.
+ service_name -- name of the service in broadcasting (channel name).
+ service_provider -- name of the service provider in broadcasting.
+ title -- name of the work.
+ track -- number of this work in the set, can be in form current/total.
+ variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
+ @endverbatim
+ *
+ * Look in the examples section for an application example how to use the Metadata API.
+ *
+ * @}
+ */
+
+/* packet functions */
+
+
+/**
+ * Allocate and read the payload of a packet and initialize its
+ * fields with default values.
+ *
+ * @param s associated IO context
+ * @param pkt packet
+ * @param size desired payload size
+ * @return >0 (read size) if OK, AVERROR_xxx otherwise
+ */
+int av_get_packet(AVIOContext *s, AVPacket *pkt, int size);
+
+
+/**
+ * Read data and append it to the current content of the AVPacket.
+ * If pkt->size is 0 this is identical to av_get_packet.
+ * Note that this uses av_grow_packet and thus involves a realloc
+ * which is inefficient. Thus this function should only be used
+ * when there is no reasonable way to know (an upper bound of)
+ * the final size.
+ *
+ * @param s associated IO context
+ * @param pkt packet
+ * @param size amount of data to read
+ * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
+ * will not be lost even if an error occurs.
+ */
+int av_append_packet(AVIOContext *s, AVPacket *pkt, int size);
+
+#if FF_API_LAVF_FRAC
+/*************************************************/
+/* fractional numbers for exact pts handling */
+
+/**
+ * The exact value of the fractional number is: 'val + num / den'.
+ * num is assumed to be 0 <= num < den.
+ */
+typedef struct AVFrac {
+ int64_t val, num, den;
+} AVFrac;
+#endif
+
+/*************************************************/
+/* input/output formats */
+
+struct AVCodecTag;
+
+/**
+ * This structure contains the data a format has to probe a file.
+ */
+typedef struct AVProbeData {
+ const char *filename;
+ unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
+ int buf_size; /**< Size of buf except extra allocated bytes */
+ const char *mime_type; /**< mime_type, when known. */
+} AVProbeData;
+
+#define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
+#define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1)
+
+#define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension
+#define AVPROBE_SCORE_MIME 75 ///< score for file mime type
+#define AVPROBE_SCORE_MAX 100 ///< maximum score
+
+#define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
+
+/// Demuxer will use avio_open, no opened file should be provided by the caller.
+#define AVFMT_NOFILE 0x0001
+#define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
+#define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
+#if FF_API_LAVF_FMT_RAWPICTURE
+#define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
+ raw picture data. @deprecated Not used anymore */
+#endif
+#define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
+#define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
+#define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
+#define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
+#define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
+#define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
+#define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
+#define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */
+#define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */
+#define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
+#define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
+#define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
+ increasing timestamps, but they must
+ still be monotonic */
+#define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative
+ timestamps. If not set the timestamp
+ will be shifted in av_write_frame and
+ av_interleaved_write_frame so they
+ start from 0.
+ The user or muxer can override this through
+ AVFormatContext.avoid_negative_ts
+ */
+
+#define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */
+
+/**
+ * @addtogroup lavf_encoding
+ * @{
+ */
+typedef struct AVOutputFormat {
+ const char *name;
+ /**
+ * Descriptive name for the format, meant to be more human-readable
+ * than name. You should use the NULL_IF_CONFIG_SMALL() macro
+ * to define it.
+ */
+ const char *long_name;
+ const char *mime_type;
+ const char *extensions; /**< comma-separated filename extensions */
+ /* output support */
+ enum AVCodecID audio_codec; /**< default audio codec */
+ enum AVCodecID video_codec; /**< default video codec */
+ enum AVCodecID subtitle_codec; /**< default subtitle codec */
+ /**
+ * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER,
+ * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
+ * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH,
+ * AVFMT_TS_NONSTRICT
+ */
+ int flags;
+
+ /**
+ * List of supported codec_id-codec_tag pairs, ordered by "better
+ * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
+ */
+ const struct AVCodecTag * const *codec_tag;
+
+
+ const AVClass *priv_class; ///< AVClass for the private context
+
+ /*****************************************************************
+ * No fields below this line are part of the public API. They
+ * may not be used outside of libavformat and can be changed and
+ * removed at will.
+ * New public fields should be added right above.
+ *****************************************************************
+ */
+ struct AVOutputFormat *next;
+ /**
+ * size of private data so that it can be allocated in the wrapper
+ */
+ int priv_data_size;
+
+ int (*write_header)(struct AVFormatContext *);
+ /**
+ * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
+ * pkt can be NULL in order to flush data buffered in the muxer.
+ * When flushing, return 0 if there still is more data to flush,
+ * or 1 if everything was flushed and there is no more buffered
+ * data.
+ */
+ int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
+ int (*write_trailer)(struct AVFormatContext *);
+ /**
+ * Currently only used to set pixel format if not YUV420P.
+ */
+ int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
+ AVPacket *in, int flush);
+ /**
+ * Test if the given codec can be stored in this container.
+ *
+ * @return 1 if the codec is supported, 0 if it is not.
+ * A negative number if unknown.
+ * MKTAG('A', 'P', 'I', 'C') if the codec is only supported as AV_DISPOSITION_ATTACHED_PIC
+ */
+ int (*query_codec)(enum AVCodecID id, int std_compliance);
+
+ void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
+ int64_t *dts, int64_t *wall);
+ /**
+ * Allows sending messages from application to device.
+ */
+ int (*control_message)(struct AVFormatContext *s, int type,
+ void *data, size_t data_size);
+
+ /**
+ * Write an uncoded AVFrame.
+ *
+ * See av_write_uncoded_frame() for details.
+ *
+ * The library will free *frame afterwards, but the muxer can prevent it
+ * by setting the pointer to NULL.
+ */
+ int (*write_uncoded_frame)(struct AVFormatContext *, int stream_index,
+ AVFrame **frame, unsigned flags);
+ /**
+ * Returns device list with it properties.
+ * @see avdevice_list_devices() for more details.
+ */
+ int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
+ /**
+ * Initialize device capabilities submodule.
+ * @see avdevice_capabilities_create() for more details.
+ */
+ int (*create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
+ /**
+ * Free device capabilities submodule.
+ * @see avdevice_capabilities_free() for more details.
+ */
+ int (*free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
+ enum AVCodecID data_codec; /**< default data codec */
+ /**
+ * Initialize format. May allocate data here, and set any AVFormatContext or
+ * AVStream parameters that need to be set before packets are sent.
+ * This method must not write output.
+ *
+ * Any allocations made here must be freed in deinit().
+ */
+ int (*init)(struct AVFormatContext *);
+ /**
+ * Deinitialize format. If present, this is called whenever the muxer is being
+ * destroyed, regardless of whether or not the header has been written.
+ *
+ * If a trailer is being written, this is called after write_trailer().
+ *
+ * This is called if init() fails as well.
+ */
+ void (*deinit)(struct AVFormatContext *);
+ /**
+ * Set up any necessary bitstream filtering and extract any extra data needed
+ * for the global header.
+ * Return 0 if more packets from this stream must be checked; 1 if not.
+ */
+ int (*check_bitstream)(struct AVFormatContext *, const AVPacket *pkt);
+} AVOutputFormat;
+/**
+ * @}
+ */
+
+/**
+ * @addtogroup lavf_decoding
+ * @{
+ */
+typedef struct AVInputFormat {
+ /**
+ * A comma separated list of short names for the format. New names
+ * may be appended with a minor bump.
+ */
+ const char *name;
+
+ /**
+ * Descriptive name for the format, meant to be more human-readable
+ * than name. You should use the NULL_IF_CONFIG_SMALL() macro
+ * to define it.
+ */
+ const char *long_name;
+
+ /**
+ * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
+ * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
+ * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
+ */
+ int flags;
+
+ /**
+ * If extensions are defined, then no probe is done. You should
+ * usually not use extension format guessing because it is not
+ * reliable enough
+ */
+ const char *extensions;
+
+ const struct AVCodecTag * const *codec_tag;
+
+ const AVClass *priv_class; ///< AVClass for the private context
+
+ /**
+ * Comma-separated list of mime types.
+ * It is used check for matching mime types while probing.
+ * @see av_probe_input_format2
+ */
+ const char *mime_type;
+
+ /*****************************************************************
+ * No fields below this line are part of the public API. They
+ * may not be used outside of libavformat and can be changed and
+ * removed at will.
+ * New public fields should be added right above.
+ *****************************************************************
+ */
+ struct AVInputFormat *next;
+
+ /**
+ * Raw demuxers store their codec ID here.
+ */
+ int raw_codec_id;
+
+ /**
+ * Size of private data so that it can be allocated in the wrapper.
+ */
+ int priv_data_size;
+
+ /**
+ * Tell if a given file has a chance of being parsed as this format.
+ * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
+ * big so you do not have to check for that unless you need more.
+ */
+ int (*read_probe)(AVProbeData *);
+
+ /**
+ * Read the format header and initialize the AVFormatContext
+ * structure. Return 0 if OK. 'avformat_new_stream' should be
+ * called to create new streams.
+ */
+ int (*read_header)(struct AVFormatContext *);
+
+ /**
+ * Read one packet and put it in 'pkt'. pts and flags are also
+ * set. 'avformat_new_stream' can be called only if the flag
+ * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
+ * background thread).
+ * @return 0 on success, < 0 on error.
+ * When returning an error, pkt must not have been allocated
+ * or must be freed before returning
+ */
+ int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
+
+ /**
+ * Close the stream. The AVFormatContext and AVStreams are not
+ * freed by this function
+ */
+ int (*read_close)(struct AVFormatContext *);
+
+ /**
+ * Seek to a given timestamp relative to the frames in
+ * stream component stream_index.
+ * @param stream_index Must not be -1.
+ * @param flags Selects which direction should be preferred if no exact
+ * match is available.
+ * @return >= 0 on success (but not necessarily the new offset)
+ */
+ int (*read_seek)(struct AVFormatContext *,
+ int stream_index, int64_t timestamp, int flags);
+
+ /**
+ * Get the next timestamp in stream[stream_index].time_base units.
+ * @return the timestamp or AV_NOPTS_VALUE if an error occurred
+ */
+ int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
+ int64_t *pos, int64_t pos_limit);
+
+ /**
+ * Start/resume playing - only meaningful if using a network-based format
+ * (RTSP).
+ */
+ int (*read_play)(struct AVFormatContext *);
+
+ /**
+ * Pause playing - only meaningful if using a network-based format
+ * (RTSP).
+ */
+ int (*read_pause)(struct AVFormatContext *);
+
+ /**
+ * Seek to timestamp ts.
+ * Seeking will be done so that the point from which all active streams
+ * can be presented successfully will be closest to ts and within min/max_ts.
+ * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
+ */
+ int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
+
+ /**
+ * Returns device list with it properties.
+ * @see avdevice_list_devices() for more details.
+ */
+ int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
+
+ /**
+ * Initialize device capabilities submodule.
+ * @see avdevice_capabilities_create() for more details.
+ */
+ int (*create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
+
+ /**
+ * Free device capabilities submodule.
+ * @see avdevice_capabilities_free() for more details.
+ */
+ int (*free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
+} AVInputFormat;
+/**
+ * @}
+ */
+
+enum AVStreamParseType {
+ AVSTREAM_PARSE_NONE,
+ AVSTREAM_PARSE_FULL, /**< full parsing and repack */
+ AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
+ AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
+ AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
+ AVSTREAM_PARSE_FULL_RAW=MKTAG(0,'R','A','W'), /**< full parsing and repack with timestamp and position generation by parser for raw
+ this assumes that each packet in the file contains no demuxer level headers and
+ just codec level data, otherwise position generation would fail */
+};
+
+typedef struct AVIndexEntry {
+ int64_t pos;
+ int64_t timestamp; /**<
+ * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
+ * when seeking to this entry. That means preferable PTS on keyframe based formats.
+ * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
+ * is known
+ */
+#define AVINDEX_KEYFRAME 0x0001
+ int flags:2;
+ int size:30; //Yeah, trying to keep the size of this small to reduce memory requirements (it is 24 vs. 32 bytes due to possible 8-byte alignment).
+ int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
+} AVIndexEntry;
+
+#define AV_DISPOSITION_DEFAULT 0x0001
+#define AV_DISPOSITION_DUB 0x0002
+#define AV_DISPOSITION_ORIGINAL 0x0004
+#define AV_DISPOSITION_COMMENT 0x0008
+#define AV_DISPOSITION_LYRICS 0x0010
+#define AV_DISPOSITION_KARAOKE 0x0020
+
+/**
+ * Track should be used during playback by default.
+ * Useful for subtitle track that should be displayed
+ * even when user did not explicitly ask for subtitles.
+ */
+#define AV_DISPOSITION_FORCED 0x0040
+#define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
+#define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
+#define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
+/**
+ * The stream is stored in the file as an attached picture/"cover art" (e.g.
+ * APIC frame in ID3v2). The single packet associated with it will be returned
+ * among the first few packets read from the file unless seeking takes place.
+ * It can also be accessed at any time in AVStream.attached_pic.
+ */
+#define AV_DISPOSITION_ATTACHED_PIC 0x0400
+
+typedef struct AVStreamInternal AVStreamInternal;
+
+/**
+ * To specify text track kind (different from subtitles default).
+ */
+#define AV_DISPOSITION_CAPTIONS 0x10000
+#define AV_DISPOSITION_DESCRIPTIONS 0x20000
+#define AV_DISPOSITION_METADATA 0x40000
+
+/**
+ * Options for behavior on timestamp wrap detection.
+ */
+#define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap
+#define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection
+#define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection
+
+/**
+ * Stream structure.
+ * New fields can be added to the end with minor version bumps.
+ * Removal, reordering and changes to existing fields require a major
+ * version bump.
+ * sizeof(AVStream) must not be used outside libav*.
+ */
+typedef struct AVStream {
+ int index; /**< stream index in AVFormatContext */
+ /**
+ * Format-specific stream ID.
+ * decoding: set by libavformat
+ * encoding: set by the user, replaced by libavformat if left unset
+ */
+ int id;
+ /**
+ * Codec context associated with this stream. Allocated and freed by
+ * libavformat.
+ *
+ * - decoding: The demuxer exports codec information stored in the headers
+ * here.
+ * - encoding: The user sets codec information, the muxer writes it to the
+ * output. Mandatory fields as specified in AVCodecContext
+ * documentation must be set even if this AVCodecContext is
+ * not actually used for encoding.
+ */
+ AVCodecContext *codec;
+ void *priv_data;
+
+#if FF_API_LAVF_FRAC
+ /**
+ * @deprecated this field is unused
+ */
+ attribute_deprecated
+ struct AVFrac pts;
+#endif
+
+ /**
+ * This is the fundamental unit of time (in seconds) in terms
+ * of which frame timestamps are represented.
+ *
+ * decoding: set by libavformat
+ * encoding: May be set by the caller before avformat_write_header() to
+ * provide a hint to the muxer about the desired timebase. In
+ * avformat_write_header(), the muxer will overwrite this field
+ * with the timebase that will actually be used for the timestamps
+ * written into the file (which may or may not be related to the
+ * user-provided one, depending on the format).
+ */
+ AVRational time_base;
+
+ /**
+ * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
+ * Only set this if you are absolutely 100% sure that the value you set
+ * it to really is the pts of the first frame.
+ * This may be undefined (AV_NOPTS_VALUE).
+ * @note The ASF header does NOT contain a correct start_time the ASF
+ * demuxer must NOT set this.
+ */
+ int64_t start_time;
+
+ /**
+ * Decoding: duration of the stream, in stream time base.
+ * If a source file does not specify a duration, but does specify
+ * a bitrate, this value will be estimated from bitrate and file size.
+ */
+ int64_t duration;
+
+ int64_t nb_frames; ///< number of frames in this stream if known or 0
+
+ int disposition; /**< AV_DISPOSITION_* bit field */
+
+ enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
+
+ /**
+ * sample aspect ratio (0 if unknown)
+ * - encoding: Set by user.
+ * - decoding: Set by libavformat.
+ */
+ AVRational sample_aspect_ratio;
+
+ AVDictionary *metadata;
+
+ /**
+ * Average framerate
+ *
+ * - demuxing: May be set by libavformat when creating the stream or in
+ * avformat_find_stream_info().
+ * - muxing: May be set by the caller before avformat_write_header().
+ */
+ AVRational avg_frame_rate;
+
+ /**
+ * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
+ * will contain the attached picture.
+ *
+ * decoding: set by libavformat, must not be modified by the caller.
+ * encoding: unused
+ */
+ AVPacket attached_pic;
+
+ /**
+ * An array of side data that applies to the whole stream (i.e. the
+ * container does not allow it to change between packets).
+ *
+ * There may be no overlap between the side data in this array and side data
+ * in the packets. I.e. a given side data is either exported by the muxer
+ * (demuxing) / set by the caller (muxing) in this array, then it never
+ * appears in the packets, or the side data is exported / sent through
+ * the packets (always in the first packet where the value becomes known or
+ * changes), then it does not appear in this array.
+ *
+ * - demuxing: Set by libavformat when the stream is created.
+ * - muxing: May be set by the caller before avformat_write_header().
+ *
+ * Freed by libavformat in avformat_free_context().
+ *
+ * @see av_format_inject_global_side_data()
+ */
+ AVPacketSideData *side_data;
+ /**
+ * The number of elements in the AVStream.side_data array.
+ */
+ int nb_side_data;
+
+ /**
+ * Flags for the user to detect events happening on the stream. Flags must
+ * be cleared by the user once the event has been handled.
+ * A combination of AVSTREAM_EVENT_FLAG_*.
+ */
+ int event_flags;
+#define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
+
+ /*****************************************************************
+ * All fields below this line are not part of the public API. They
+ * may not be used outside of libavformat and can be changed and
+ * removed at will.
+ * New public fields should be added right above.
+ *****************************************************************
+ */
+
+ /**
+ * Stream information used internally by av_find_stream_info()
+ */
+#define MAX_STD_TIMEBASES (30*12+30+3+6)
+ struct {
+ int64_t last_dts;
+ int64_t duration_gcd;
+ int duration_count;
+ int64_t rfps_duration_sum;
+ double (*duration_error)[2][MAX_STD_TIMEBASES];
+ int64_t codec_info_duration;
+ int64_t codec_info_duration_fields;
+
+ /**
+ * 0 -> decoder has not been searched for yet.
+ * >0 -> decoder found
+ * <0 -> decoder with codec_id == -found_decoder has not been found
+ */
+ int found_decoder;
+
+ int64_t last_duration;
+
+ /**
+ * Those are used for average framerate estimation.
+ */
+ int64_t fps_first_dts;
+ int fps_first_dts_idx;
+ int64_t fps_last_dts;
+ int fps_last_dts_idx;
+
+ } *info;
+
+ int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
+
+ // Timestamp generation support:
+ /**
+ * Timestamp corresponding to the last dts sync point.
+ *
+ * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
+ * a DTS is received from the underlying container. Otherwise set to
+ * AV_NOPTS_VALUE by default.
+ */
+ int64_t first_dts;
+ int64_t cur_dts;
+ int64_t last_IP_pts;
+ int last_IP_duration;
+
+ /**
+ * Number of packets to buffer for codec probing
+ */
+ int probe_packets;
+
+ /**
+ * Number of frames that have been demuxed during av_find_stream_info()
+ */
+ int codec_info_nb_frames;
+
+ /* av_read_frame() support */
+ enum AVStreamParseType need_parsing;
+ struct AVCodecParserContext *parser;
+
+ /**
+ * last packet in packet_buffer for this stream when muxing.
+ */
+ struct AVPacketList *last_in_packet_buffer;
+ AVProbeData probe_data;
+#define MAX_REORDER_DELAY 16
+ int64_t pts_buffer[MAX_REORDER_DELAY+1];
+
+ AVIndexEntry *index_entries; /**< Only used if the format does not
+ support seeking natively. */
+ int nb_index_entries;
+ unsigned int index_entries_allocated_size;
+
+ /**
+ * Real base framerate of the stream.
+ * This is the lowest framerate with which all timestamps can be
+ * represented accurately (it is the least common multiple of all
+ * framerates in the stream). Note, this value is just a guess!
+ * For example, if the time base is 1/90000 and all frames have either
+ * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
+ *
+ * Code outside avformat should access this field using:
+ * av_stream_get/set_r_frame_rate(stream)
+ */
+ AVRational r_frame_rate;
+
+ /**
+ * Stream Identifier
+ * This is the MPEG-TS stream identifier +1
+ * 0 means unknown
+ */
+ int stream_identifier;
+
+ int64_t interleaver_chunk_size;
+ int64_t interleaver_chunk_duration;
+
+ /**
+ * stream probing state
+ * -1 -> probing finished
+ * 0 -> no probing requested
+ * rest -> perform probing with request_probe being the minimum score to accept.
+ * NOT PART OF PUBLIC API
+ */
+ int request_probe;
+ /**
+ * Indicates that everything up to the next keyframe
+ * should be discarded.
+ */
+ int skip_to_keyframe;
+
+ /**
+ * Number of samples to skip at the start of the frame decoded from the next packet.
+ */
+ int skip_samples;
+
+ /**
+ * If not 0, the number of samples that should be skipped from the start of
+ * the stream (the samples are removed from packets with pts==0, which also
+ * assumes negative timestamps do not happen).
+ * Intended for use with formats such as mp3 with ad-hoc gapless audio
+ * support.
+ */
+ int64_t start_skip_samples;
+
+ /**
+ * If not 0, the first audio sample that should be discarded from the stream.
+ * This is broken by design (needs global sample count), but can't be
+ * avoided for broken by design formats such as mp3 with ad-hoc gapless
+ * audio support.
+ */
+ int64_t first_discard_sample;
+
+ /**
+ * The sample after last sample that is intended to be discarded after
+ * first_discard_sample. Works on frame boundaries only. Used to prevent
+ * early EOF if the gapless info is broken (considered concatenated mp3s).
+ */
+ int64_t last_discard_sample;
+
+ /**
+ * Number of internally decoded frames, used internally in libavformat, do not access
+ * its lifetime differs from info which is why it is not in that structure.
+ */
+ int nb_decoded_frames;
+
+ /**
+ * Timestamp offset added to timestamps before muxing
+ * NOT PART OF PUBLIC API
+ */
+ int64_t mux_ts_offset;
+
+ /**
+ * Internal data to check for wrapping of the time stamp
+ */
+ int64_t pts_wrap_reference;
+
+ /**
+ * Options for behavior, when a wrap is detected.
+ *
+ * Defined by AV_PTS_WRAP_ values.
+ *
+ * If correction is enabled, there are two possibilities:
+ * If the first time stamp is near the wrap point, the wrap offset
+ * will be subtracted, which will create negative time stamps.
+ * Otherwise the offset will be added.
+ */
+ int pts_wrap_behavior;
+
+ /**
+ * Internal data to prevent doing update_initial_durations() twice
+ */
+ int update_initial_durations_done;
+
+ /**
+ * Internal data to generate dts from pts
+ */
+ int64_t pts_reorder_error[MAX_REORDER_DELAY+1];
+ uint8_t pts_reorder_error_count[MAX_REORDER_DELAY+1];
+
+ /**
+ * Internal data to analyze DTS and detect faulty mpeg streams
+ */
+ int64_t last_dts_for_order_check;
+ uint8_t dts_ordered;
+ uint8_t dts_misordered;
+
+ /**
+ * Internal data to inject global side data
+ */
+ int inject_global_side_data;
+
+ /**
+ * String containing paris of key and values describing recommended encoder configuration.
+ * Paris are separated by ','.
+ * Keys are separated from values by '='.
+ */
+ char *recommended_encoder_configuration;
+
+ /**
+ * display aspect ratio (0 if unknown)
+ * - encoding: unused
+ * - decoding: Set by libavformat to calculate sample_aspect_ratio internally
+ */
+ AVRational display_aspect_ratio;
+
+ struct FFFrac *priv_pts;
+
+ /**
+ * An opaque field for libavformat internal usage.
+ * Must not be accessed in any way by callers.
+ */
+ AVStreamInternal *internal;
+} AVStream;
+
+AVRational av_stream_get_r_frame_rate(const AVStream *s);
+void av_stream_set_r_frame_rate(AVStream *s, AVRational r);
+struct AVCodecParserContext *av_stream_get_parser(const AVStream *s);
+char* av_stream_get_recommended_encoder_configuration(const AVStream *s);
+void av_stream_set_recommended_encoder_configuration(AVStream *s, char *configuration);
+
+/**
+ * Returns the pts of the last muxed packet + its duration
+ *
+ * the retuned value is undefined when used with a demuxer.
+ */
+int64_t av_stream_get_end_pts(const AVStream *st);
+
+#define AV_PROGRAM_RUNNING 1
+
+/**
+ * New fields can be added to the end with minor version bumps.
+ * Removal, reordering and changes to existing fields require a major
+ * version bump.
+ * sizeof(AVProgram) must not be used outside libav*.
+ */
+typedef struct AVProgram {
+ int id;
+ int flags;
+ enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
+ unsigned int *stream_index;
+ unsigned int nb_stream_indexes;
+ AVDictionary *metadata;
+
+ int program_num;
+ int pmt_pid;
+ int pcr_pid;
+
+ /*****************************************************************
+ * All fields below this line are not part of the public API. They
+ * may not be used outside of libavformat and can be changed and
+ * removed at will.
+ * New public fields should be added right above.
+ *****************************************************************
+ */
+ int64_t start_time;
+ int64_t end_time;
+
+ int64_t pts_wrap_reference; ///< reference dts for wrap detection
+ int pts_wrap_behavior; ///< behavior on wrap detection
+} AVProgram;
+
+#define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
+ (streams are added dynamically) */
+
+typedef struct AVChapter {
+ int id; ///< unique ID to identify the chapter
+ AVRational time_base; ///< time base in which the start/end timestamps are specified
+ int64_t start, end; ///< chapter start/end time in time_base units
+ AVDictionary *metadata;
+} AVChapter;
+
+
+/**
+ * Callback used by devices to communicate with application.
+ */
+typedef int (*av_format_control_message)(struct AVFormatContext *s, int type,
+ void *data, size_t data_size);
+
+typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
+ const AVIOInterruptCB *int_cb, AVDictionary **options);
+
+/**
+ * The duration of a video can be estimated through various ways, and this enum can be used
+ * to know how the duration was estimated.
+ */
+enum AVDurationEstimationMethod {
+ AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes
+ AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
+ AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
+};
+
+typedef struct AVFormatInternal AVFormatInternal;
+
+/**
+ * Format I/O context.
+ * New fields can be added to the end with minor version bumps.
+ * Removal, reordering and changes to existing fields require a major
+ * version bump.
+ * sizeof(AVFormatContext) must not be used outside libav*, use
+ * avformat_alloc_context() to create an AVFormatContext.
+ */
+typedef struct AVFormatContext {
+ /**
+ * A class for logging and @ref avoptions. Set by avformat_alloc_context().
+ * Exports (de)muxer private options if they exist.
+ */
+ const AVClass *av_class;
+
+ /**
+ * The input container format.
+ *
+ * Demuxing only, set by avformat_open_input().
+ */
+ struct AVInputFormat *iformat;
+
+ /**
+ * The output container format.
+ *
+ * Muxing only, must be set by the caller before avformat_write_header().
+ */
+ struct AVOutputFormat *oformat;
+
+ /**
+ * Format private data. This is an AVOptions-enabled struct
+ * if and only if iformat/oformat.priv_class is not NULL.
+ *
+ * - muxing: set by avformat_write_header()
+ * - demuxing: set by avformat_open_input()
+ */
+ void *priv_data;
+
+ /**
+ * I/O context.
+ *
+ * - demuxing: either set by the user before avformat_open_input() (then
+ * the user must close it manually) or set by avformat_open_input().
+ * - muxing: set by the user before avformat_write_header(). The caller must
+ * take care of closing / freeing the IO context.
+ *
+ * Do NOT set this field if AVFMT_NOFILE flag is set in
+ * iformat/oformat.flags. In such a case, the (de)muxer will handle
+ * I/O in some other way and this field will be NULL.
+ */
+ AVIOContext *pb;
+
+ /* stream info */
+ /**
+ * Flags signalling stream properties. A combination of AVFMTCTX_*.
+ * Set by libavformat.
+ */
+ int ctx_flags;
+
+ /**
+ * Number of elements in AVFormatContext.streams.
+ *
+ * Set by avformat_new_stream(), must not be modified by any other code.
+ */
+ unsigned int nb_streams;
+ /**
+ * A list of all streams in the file. New streams are created with
+ * avformat_new_stream().
+ *
+ * - demuxing: streams are created by libavformat in avformat_open_input().
+ * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
+ * appear in av_read_frame().
+ * - muxing: streams are created by the user before avformat_write_header().
+ *
+ * Freed by libavformat in avformat_free_context().
+ */
+ AVStream **streams;
+
+ /**
+ * input or output filename
+ *
+ * - demuxing: set by avformat_open_input()
+ * - muxing: may be set by the caller before avformat_write_header()
+ */
+ char filename[1024];
+
+ /**
+ * Position of the first frame of the component, in
+ * AV_TIME_BASE fractional seconds. NEVER set this value directly:
+ * It is deduced from the AVStream values.
+ *
+ * Demuxing only, set by libavformat.
+ */
+ int64_t start_time;
+
+ /**
+ * Duration of the stream, in AV_TIME_BASE fractional
+ * seconds. Only set this value if you know none of the individual stream
+ * durations and also do not set any of them. This is deduced from the
+ * AVStream values if not set.
+ *
+ * Demuxing only, set by libavformat.
+ */
+ int64_t duration;
+
+ /**
+ * Total stream bitrate in bit/s, 0 if not
+ * available. Never set it directly if the file_size and the
+ * duration are known as FFmpeg can compute it automatically.
+ */
+ int64_t bit_rate;
+
+ unsigned int packet_size;
+ int max_delay;
+
+ /**
+ * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*.
+ * Set by the user before avformat_open_input() / avformat_write_header().
+ */
+ int flags;
+#define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
+#define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
+#define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
+#define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
+#define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
+#define AVFMT_FLAG_NOPARSE 0x0020 ///< Do not use AVParsers, you also must set AVFMT_FLAG_NOFILLIN as the fillin code works on frames and no parsing -> no frames. Also seeking to frames can not work if parsing to find frame boundaries has been disabled
+#define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
+#define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
+#define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
+#define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet.
+/**
+ * When muxing, try to avoid writing any random/volatile data to the output.
+ * This includes any random IDs, real-time timestamps/dates, muxer version, etc.
+ *
+ * This flag is mainly intended for testing.
+ */
+#define AVFMT_FLAG_BITEXACT 0x0400
+#define AVFMT_FLAG_MP4A_LATM 0x8000 ///< Enable RTP MP4A-LATM payload
+#define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
+#define AVFMT_FLAG_PRIV_OPT 0x20000 ///< Enable use of private options by delaying codec open (this could be made default once all code is converted)
+#define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Don't merge side data but keep it separate.
+#define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats
+
+ /**
+ * Maximum size of the data read from input for determining
+ * the input container format.
+ * Demuxing only, set by the caller before avformat_open_input().
+ */
+ int64_t probesize;
+
+ /**
+ * Maximum duration (in AV_TIME_BASE units) of the data read
+ * from input in avformat_find_stream_info().
+ * Demuxing only, set by the caller before avformat_find_stream_info().
+ * Can be set to 0 to let avformat choose using a heuristic.
+ */
+ int64_t max_analyze_duration;
+
+ const uint8_t *key;
+ int keylen;
+
+ unsigned int nb_programs;
+ AVProgram **programs;
+
+ /**
+ * Forced video codec_id.
+ * Demuxing: Set by user.
+ */
+ enum AVCodecID video_codec_id;
+
+ /**
+ * Forced audio codec_id.
+ * Demuxing: Set by user.
+ */
+ enum AVCodecID audio_codec_id;
+
+ /**
+ * Forced subtitle codec_id.
+ * Demuxing: Set by user.
+ */
+ enum AVCodecID subtitle_codec_id;
+
+ /**
+ * Maximum amount of memory in bytes to use for the index of each stream.
+ * If the index exceeds this size, entries will be discarded as
+ * needed to maintain a smaller size. This can lead to slower or less
+ * accurate seeking (depends on demuxer).
+ * Demuxers for which a full in-memory index is mandatory will ignore
+ * this.
+ * - muxing: unused
+ * - demuxing: set by user
+ */
+ unsigned int max_index_size;
+
+ /**
+ * Maximum amount of memory in bytes to use for buffering frames
+ * obtained from realtime capture devices.
+ */
+ unsigned int max_picture_buffer;
+
+ /**
+ * Number of chapters in AVChapter array.
+ * When muxing, chapters are normally written in the file header,
+ * so nb_chapters should normally be initialized before write_header
+ * is called. Some muxers (e.g. mov and mkv) can also write chapters
+ * in the trailer. To write chapters in the trailer, nb_chapters
+ * must be zero when write_header is called and non-zero when
+ * write_trailer is called.
+ * - muxing: set by user
+ * - demuxing: set by libavformat
+ */
+ unsigned int nb_chapters;
+ AVChapter **chapters;
+
+ /**
+ * Metadata that applies to the whole file.
+ *
+ * - demuxing: set by libavformat in avformat_open_input()
+ * - muxing: may be set by the caller before avformat_write_header()
+ *
+ * Freed by libavformat in avformat_free_context().
+ */
+ AVDictionary *metadata;
+
+ /**
+ * Start time of the stream in real world time, in microseconds
+ * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the
+ * stream was captured at this real world time.
+ * - muxing: Set by the caller before avformat_write_header(). If set to
+ * either 0 or AV_NOPTS_VALUE, then the current wall-time will
+ * be used.
+ * - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
+ * the value may become known after some number of frames
+ * have been received.
+ */
+ int64_t start_time_realtime;
+
+ /**
+ * The number of frames used for determining the framerate in
+ * avformat_find_stream_info().
+ * Demuxing only, set by the caller before avformat_find_stream_info().
+ */
+ int fps_probe_size;
+
+ /**
+ * Error recognition; higher values will detect more errors but may
+ * misdetect some more or less valid parts as errors.
+ * Demuxing only, set by the caller before avformat_open_input().
+ */
+ int error_recognition;
+
+ /**
+ * Custom interrupt callbacks for the I/O layer.
+ *
+ * demuxing: set by the user before avformat_open_input().
+ * muxing: set by the user before avformat_write_header()
+ * (mainly useful for AVFMT_NOFILE formats). The callback
+ * should also be passed to avio_open2() if it's used to
+ * open the file.
+ */
+ AVIOInterruptCB interrupt_callback;
+
+ /**
+ * Flags to enable debugging.
+ */
+ int debug;
+#define FF_FDEBUG_TS 0x0001
+
+ /**
+ * Maximum buffering duration for interleaving.
+ *
+ * To ensure all the streams are interleaved correctly,
+ * av_interleaved_write_frame() will wait until it has at least one packet
+ * for each stream before actually writing any packets to the output file.
+ * When some streams are "sparse" (i.e. there are large gaps between
+ * successive packets), this can result in excessive buffering.
+ *
+ * This field specifies the maximum difference between the timestamps of the
+ * first and the last packet in the muxing queue, above which libavformat
+ * will output a packet regardless of whether it has queued a packet for all
+ * the streams.
+ *
+ * Muxing only, set by the caller before avformat_write_header().
+ */
+ int64_t max_interleave_delta;
+
+ /**
+ * Allow non-standard and experimental extension
+ * @see AVCodecContext.strict_std_compliance
+ */
+ int strict_std_compliance;
+
+ /**
+ * Flags for the user to detect events happening on the file. Flags must
+ * be cleared by the user once the event has been handled.
+ * A combination of AVFMT_EVENT_FLAG_*.
+ */
+ int event_flags;
+#define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
+
+ /**
+ * Maximum number of packets to read while waiting for the first timestamp.
+ * Decoding only.
+ */
+ int max_ts_probe;
+
+ /**
+ * Avoid negative timestamps during muxing.
+ * Any value of the AVFMT_AVOID_NEG_TS_* constants.
+ * Note, this only works when using av_interleaved_write_frame. (interleave_packet_per_dts is in use)
+ * - muxing: Set by user
+ * - demuxing: unused
+ */
+ int avoid_negative_ts;
+#define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format
+#define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative
+#define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0
+
+ /**
+ * Transport stream id.
+ * This will be moved into demuxer private options. Thus no API/ABI compatibility
+ */
+ int ts_id;
+
+ /**
+ * Audio preload in microseconds.
+ * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
+ * - encoding: Set by user via AVOptions (NO direct access)
+ * - decoding: unused
+ */
+ int audio_preload;
+
+ /**
+ * Max chunk time in microseconds.
+ * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
+ * - encoding: Set by user via AVOptions (NO direct access)
+ * - decoding: unused
+ */
+ int max_chunk_duration;
+
+ /**
+ * Max chunk size in bytes
+ * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
+ * - encoding: Set by user via AVOptions (NO direct access)
+ * - decoding: unused
+ */
+ int max_chunk_size;
+
+ /**
+ * forces the use of wallclock timestamps as pts/dts of packets
+ * This has undefined results in the presence of B frames.
+ * - encoding: unused
+ * - decoding: Set by user via AVOptions (NO direct access)
+ */
+ int use_wallclock_as_timestamps;
+
+ /**
+ * avio flags, used to force AVIO_FLAG_DIRECT.
+ * - encoding: unused
+ * - decoding: Set by user via AVOptions (NO direct access)
+ */
+ int avio_flags;
+
+ /**
+ * The duration field can be estimated through various ways, and this field can be used
+ * to know how the duration was estimated.
+ * - encoding: unused
+ * - decoding: Read by user via AVOptions (NO direct access)
+ */
+ enum AVDurationEstimationMethod duration_estimation_method;
+
+ /**
+ * Skip initial bytes when opening stream
+ * - encoding: unused
+ * - decoding: Set by user via AVOptions (NO direct access)
+ */
+ int64_t skip_initial_bytes;
+
+ /**
+ * Correct single timestamp overflows
+ * - encoding: unused
+ * - decoding: Set by user via AVOptions (NO direct access)
+ */
+ unsigned int correct_ts_overflow;
+
+ /**
+ * Force seeking to any (also non key) frames.
+ * - encoding: unused
+ * - decoding: Set by user via AVOptions (NO direct access)
+ */
+ int seek2any;
+
+ /**
+ * Flush the I/O context after each packet.
+ * - encoding: Set by user via AVOptions (NO direct access)
+ * - decoding: unused
+ */
+ int flush_packets;
+
+ /**
+ * format probing score.
+ * The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
+ * the format.
+ * - encoding: unused
+ * - decoding: set by avformat, read by user via av_format_get_probe_score() (NO direct access)
+ */
+ int probe_score;
+
+ /**
+ * number of bytes to read maximally to identify format.
+ * - encoding: unused
+ * - decoding: set by user through AVOPtions (NO direct access)
+ */
+ int format_probesize;
+
+ /**
+ * ',' separated list of allowed decoders.
+ * If NULL then all are allowed
+ * - encoding: unused
+ * - decoding: set by user through AVOptions (NO direct access)
+ */
+ char *codec_whitelist;
+
+ /**
+ * ',' separated list of allowed demuxers.
+ * If NULL then all are allowed
+ * - encoding: unused
+ * - decoding: set by user through AVOptions (NO direct access)
+ */
+ char *format_whitelist;
+
+ /**
+ * An opaque field for libavformat internal usage.
+ * Must not be accessed in any way by callers.
+ */
+ AVFormatInternal *internal;
+
+ /**
+ * IO repositioned flag.
+ * This is set by avformat when the underlaying IO context read pointer
+ * is repositioned, for example when doing byte based seeking.
+ * Demuxers can use the flag to detect such changes.
+ */
+ int io_repositioned;
+
+ /**
+ * Forced video codec.
+ * This allows forcing a specific decoder, even when there are multiple with
+ * the same codec_id.
+ * Demuxing: Set by user via av_format_set_video_codec (NO direct access).
+ */
+ AVCodec *video_codec;
+
+ /**
+ * Forced audio codec.
+ * This allows forcing a specific decoder, even when there are multiple with
+ * the same codec_id.
+ * Demuxing: Set by user via av_format_set_audio_codec (NO direct access).
+ */
+ AVCodec *audio_codec;
+
+ /**
+ * Forced subtitle codec.
+ * This allows forcing a specific decoder, even when there are multiple with
+ * the same codec_id.
+ * Demuxing: Set by user via av_format_set_subtitle_codec (NO direct access).
+ */
+ AVCodec *subtitle_codec;
+
+ /**
+ * Forced data codec.
+ * This allows forcing a specific decoder, even when there are multiple with
+ * the same codec_id.
+ * Demuxing: Set by user via av_format_set_data_codec (NO direct access).
+ */
+ AVCodec *data_codec;
+
+ /**
+ * Number of bytes to be written as padding in a metadata header.
+ * Demuxing: Unused.
+ * Muxing: Set by user via av_format_set_metadata_header_padding.
+ */
+ int metadata_header_padding;
+
+ /**
+ * User data.
+ * This is a place for some private data of the user.
+ */
+ void *opaque;
+
+ /**
+ * Callback used by devices to communicate with application.
+ */
+ av_format_control_message control_message_cb;
+
+ /**
+ * Output timestamp offset, in microseconds.
+ * Muxing: set by user via AVOptions (NO direct access)
+ */
+ int64_t output_ts_offset;
+
+ /**
+ * dump format separator.
+ * can be ", " or "\n " or anything else
+ * Code outside libavformat should access this field using AVOptions
+ * (NO direct access).
+ * - muxing: Set by user.
+ * - demuxing: Set by user.
+ */
+ uint8_t *dump_separator;
+
+ /**
+ * Forced Data codec_id.
+ * Demuxing: Set by user.
+ */
+ enum AVCodecID data_codec_id;
+
+#if FF_API_OLD_OPEN_CALLBACKS
+ /**
+ * Called to open further IO contexts when needed for demuxing.
+ *
+ * This can be set by the user application to perform security checks on
+ * the URLs before opening them.
+ * The function should behave like avio_open2(), AVFormatContext is provided
+ * as contextual information and to reach AVFormatContext.opaque.
+ *
+ * If NULL then some simple checks are used together with avio_open2().
+ *
+ * Must not be accessed directly from outside avformat.
+ * @See av_format_set_open_cb()
+ *
+ * Demuxing: Set by user.
+ *
+ * @deprecated Use io_open and io_close.
+ */
+ attribute_deprecated
+ int (*open_cb)(struct AVFormatContext *s, AVIOContext **p, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options);
+#endif
+
+ /**
+ * ',' separated list of allowed protocols.
+ * - encoding: unused
+ * - decoding: set by user through AVOptions (NO direct access)
+ */
+ char *protocol_whitelist;
+
+ /*
+ * A callback for opening new IO streams.
+ *
+ * Certain muxers or demuxers (e.g. for various playlist-based formats) need
+ * to open additional files during muxing or demuxing. This callback allows
+ * the caller to provide custom IO in such cases.
+ *
+ * @param s the format context
+ * @param pb on success, the newly opened IO context should be returned here
+ * @param url the url to open
+ * @param flags a combination of AVIO_FLAG_*
+ * @param options a dictionary of additional options, with the same
+ * semantics as in avio_open2()
+ * @return 0 on success, a negative AVERROR code on failure
+ *
+ * @note Certain muxers and demuxers do nesting, i.e. they open one or more
+ * additional internal format contexts. Thus the AVFormatContext pointer
+ * passed to this callback may be different from the one facing the caller.
+ * It will, however, have the same 'opaque' field.
+ */
+ int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
+ int flags, AVDictionary **options);
+
+ /**
+ * A callback for closing the streams opened with AVFormatContext.io_open().
+ */
+ void (*io_close)(struct AVFormatContext *s, AVIOContext *pb);
+
+ /**
+ * The maximum number of streams.
+ * - encoding: unused
+ * - decoding: set by user through AVOptions (NO direct access)
+ */
+ int max_streams;
+} AVFormatContext;
+
+int av_format_get_probe_score(const AVFormatContext *s);
+AVCodec * av_format_get_video_codec(const AVFormatContext *s);
+void av_format_set_video_codec(AVFormatContext *s, AVCodec *c);
+AVCodec * av_format_get_audio_codec(const AVFormatContext *s);
+void av_format_set_audio_codec(AVFormatContext *s, AVCodec *c);
+AVCodec * av_format_get_subtitle_codec(const AVFormatContext *s);
+void av_format_set_subtitle_codec(AVFormatContext *s, AVCodec *c);
+AVCodec * av_format_get_data_codec(const AVFormatContext *s);
+void av_format_set_data_codec(AVFormatContext *s, AVCodec *c);
+int av_format_get_metadata_header_padding(const AVFormatContext *s);
+void av_format_set_metadata_header_padding(AVFormatContext *s, int c);
+void * av_format_get_opaque(const AVFormatContext *s);
+void av_format_set_opaque(AVFormatContext *s, void *opaque);
+av_format_control_message av_format_get_control_message_cb(const AVFormatContext *s);
+void av_format_set_control_message_cb(AVFormatContext *s, av_format_control_message callback);
+#if FF_API_OLD_OPEN_CALLBACKS
+attribute_deprecated AVOpenCallback av_format_get_open_cb(const AVFormatContext *s);
+attribute_deprecated void av_format_set_open_cb(AVFormatContext *s, AVOpenCallback callback);
+#endif
+
+/**
+ * This function will cause global side data to be injected in the next packet
+ * of each stream as well as after any subsequent seek.
+ */
+void av_format_inject_global_side_data(AVFormatContext *s);
+
+/**
+ * Returns the method used to set ctx->duration.
+ *
+ * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
+ */
+enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx);
+
+typedef struct AVPacketList {
+ AVPacket pkt;
+ struct AVPacketList *next;
+} AVPacketList;
+
+
+/**
+ * @defgroup lavf_core Core functions
+ * @ingroup libavf
+ *
+ * Functions for querying libavformat capabilities, allocating core structures,
+ * etc.
+ * @{
+ */
+
+/**
+ * Return the LIBAVFORMAT_VERSION_INT constant.
+ */
+unsigned avformat_version(void);
+
+/**
+ * Return the libavformat build-time configuration.
+ */
+const char *avformat_configuration(void);
+
+/**
+ * Return the libavformat license.
+ */
+const char *avformat_license(void);
+
+/**
+ * Initialize libavformat and register all the muxers, demuxers and
+ * protocols. If you do not call this function, then you can select
+ * exactly which formats you want to support.
+ *
+ * @see av_register_input_format()
+ * @see av_register_output_format()
+ */
+void av_register_all(void);
+
+void av_register_input_format(AVInputFormat *format);
+void av_register_output_format(AVOutputFormat *format);
+
+/**
+ * Do global initialization of network components. This is optional,
+ * but recommended, since it avoids the overhead of implicitly
+ * doing the setup for each session.
+ *
+ * Calling this function will become mandatory if using network
+ * protocols at some major version bump.
+ */
+int avformat_network_init(void);
+
+/**
+ * Undo the initialization done by avformat_network_init.
+ */
+int avformat_network_deinit(void);
+
+/**
+ * If f is NULL, returns the first registered input format,
+ * if f is non-NULL, returns the next registered input format after f
+ * or NULL if f is the last one.
+ */
+AVInputFormat *av_iformat_next(const AVInputFormat *f);
+
+/**
+ * If f is NULL, returns the first registered output format,
+ * if f is non-NULL, returns the next registered output format after f
+ * or NULL if f is the last one.
+ */
+AVOutputFormat *av_oformat_next(const AVOutputFormat *f);
+
+/**
+ * Allocate an AVFormatContext.
+ * avformat_free_context() can be used to free the context and everything
+ * allocated by the framework within it.
+ */
+AVFormatContext *avformat_alloc_context(void);
+
+/**
+ * Free an AVFormatContext and all its streams.
+ * @param s context to free
+ */
+void avformat_free_context(AVFormatContext *s);
+
+/**
+ * Get the AVClass for AVFormatContext. It can be used in combination with
+ * AV_OPT_SEARCH_FAKE_OBJ for examining options.
+ *
+ * @see av_opt_find().
+ */
+const AVClass *avformat_get_class(void);
+
+/**
+ * Add a new stream to a media file.
+ *
+ * When demuxing, it is called by the demuxer in read_header(). If the
+ * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
+ * be called in read_packet().
+ *
+ * When muxing, should be called by the user before avformat_write_header().
+ *
+ * User is required to call avcodec_close() and avformat_free_context() to
+ * clean up the allocation by avformat_new_stream().
+ *
+ * @param s media file handle
+ * @param c If non-NULL, the AVCodecContext corresponding to the new stream
+ * will be initialized to use this codec. This is needed for e.g. codec-specific
+ * defaults to be set, so codec should be provided if it is known.
+ *
+ * @return newly created stream or NULL on error.
+ */
+AVStream *avformat_new_stream(AVFormatContext *s, const AVCodec *c);
+
+/**
+ * Allocate new information from stream.
+ *
+ * @param stream stream
+ * @param type desired side information type
+ * @param size side information size
+ * @return pointer to fresh allocated data or NULL otherwise
+ */
+uint8_t *av_stream_new_side_data(AVStream *stream,
+ enum AVPacketSideDataType type, int size);
+/**
+ * Get side information from stream.
+ *
+ * @param stream stream
+ * @param type desired side information type
+ * @param size pointer for side information size to store (optional)
+ * @return pointer to data if present or NULL otherwise
+ */
+uint8_t *av_stream_get_side_data(AVStream *stream,
+ enum AVPacketSideDataType type, int *size);
+
+AVProgram *av_new_program(AVFormatContext *s, int id);
+
+/**
+ * @}
+ */
+
+
+/**
+ * Allocate an AVFormatContext for an output format.
+ * avformat_free_context() can be used to free the context and
+ * everything allocated by the framework within it.
+ *
+ * @param *ctx is set to the created format context, or to NULL in
+ * case of failure
+ * @param oformat format to use for allocating the context, if NULL
+ * format_name and filename are used instead
+ * @param format_name the name of output format to use for allocating the
+ * context, if NULL filename is used instead
+ * @param filename the name of the filename to use for allocating the
+ * context, may be NULL
+ * @return >= 0 in case of success, a negative AVERROR code in case of
+ * failure
+ */
+int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat,
+ const char *format_name, const char *filename);
+
+/**
+ * @addtogroup lavf_decoding
+ * @{
+ */
+
+/**
+ * Find AVInputFormat based on the short name of the input format.
+ */
+AVInputFormat *av_find_input_format(const char *short_name);
+
+/**
+ * Guess the file format.
+ *
+ * @param pd data to be probed
+ * @param is_opened Whether the file is already opened; determines whether
+ * demuxers with or without AVFMT_NOFILE are probed.
+ */
+AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
+
+/**
+ * Guess the file format.
+ *
+ * @param pd data to be probed
+ * @param is_opened Whether the file is already opened; determines whether
+ * demuxers with or without AVFMT_NOFILE are probed.
+ * @param score_max A probe score larger that this is required to accept a
+ * detection, the variable is set to the actual detection
+ * score afterwards.
+ * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
+ * to retry with a larger probe buffer.
+ */
+AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
+
+/**
+ * Guess the file format.
+ *
+ * @param is_opened Whether the file is already opened; determines whether
+ * demuxers with or without AVFMT_NOFILE are probed.
+ * @param score_ret The score of the best detection.
+ */
+AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret);
+
+/**
+ * Probe a bytestream to determine the input format. Each time a probe returns
+ * with a score that is too low, the probe buffer size is increased and another
+ * attempt is made. When the maximum probe size is reached, the input format
+ * with the highest score is returned.
+ *
+ * @param pb the bytestream to probe
+ * @param fmt the input format is put here
+ * @param url the url of the stream
+ * @param logctx the log context
+ * @param offset the offset within the bytestream to probe from
+ * @param max_probe_size the maximum probe buffer size (zero for default)
+ * @return the score in case of success, a negative value corresponding to an
+ * the maximal score is AVPROBE_SCORE_MAX
+ * AVERROR code otherwise
+ */
+int av_probe_input_buffer2(AVIOContext *pb, AVInputFormat **fmt,
+ const char *url, void *logctx,
+ unsigned int offset, unsigned int max_probe_size);
+
+/**
+ * Like av_probe_input_buffer2() but returns 0 on success
+ */
+int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
+ const char *url, void *logctx,
+ unsigned int offset, unsigned int max_probe_size);
+
+/**
+ * Open an input stream and read the header. The codecs are not opened.
+ * The stream must be closed with avformat_close_input().
+ *
+ * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
+ * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
+ * function and written into ps.
+ * Note that a user-supplied AVFormatContext will be freed on failure.
+ * @param url URL of the stream to open.
+ * @param fmt If non-NULL, this parameter forces a specific input format.
+ * Otherwise the format is autodetected.
+ * @param options A dictionary filled with AVFormatContext and demuxer-private options.
+ * On return this parameter will be destroyed and replaced with a dict containing
+ * options that were not found. May be NULL.
+ *
+ * @return 0 on success, a negative AVERROR on failure.
+ *
+ * @note If you want to use custom IO, preallocate the format context and set its pb field.
+ */
+int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options);
+
+attribute_deprecated
+int av_demuxer_open(AVFormatContext *ic);
+
+/**
+ * Read packets of a media file to get stream information. This
+ * is useful for file formats with no headers such as MPEG. This
+ * function also computes the real framerate in case of MPEG-2 repeat
+ * frame mode.
+ * The logical file position is not changed by this function;
+ * examined packets may be buffered for later processing.
+ *
+ * @param ic media file handle
+ * @param options If non-NULL, an ic.nb_streams long array of pointers to
+ * dictionaries, where i-th member contains options for
+ * codec corresponding to i-th stream.
+ * On return each dictionary will be filled with options that were not found.
+ * @return >=0 if OK, AVERROR_xxx on error
+ *
+ * @note this function isn't guaranteed to open all the codecs, so
+ * options being non-empty at return is a perfectly normal behavior.
+ *
+ * @todo Let the user decide somehow what information is needed so that
+ * we do not waste time getting stuff the user does not need.
+ */
+int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options);
+
+/**
+ * Find the programs which belong to a given stream.
+ *
+ * @param ic media file handle
+ * @param last the last found program, the search will start after this
+ * program, or from the beginning if it is NULL
+ * @param s stream index
+ * @return the next program which belongs to s, NULL if no program is found or
+ * the last program is not among the programs of ic.
+ */
+AVProgram *av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s);
+
+void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
+
+/**
+ * Find the "best" stream in the file.
+ * The best stream is determined according to various heuristics as the most
+ * likely to be what the user expects.
+ * If the decoder parameter is non-NULL, av_find_best_stream will find the
+ * default decoder for the stream's codec; streams for which no decoder can
+ * be found are ignored.
+ *
+ * @param ic media file handle
+ * @param type stream type: video, audio, subtitles, etc.
+ * @param wanted_stream_nb user-requested stream number,
+ * or -1 for automatic selection
+ * @param related_stream try to find a stream related (eg. in the same
+ * program) to this one, or -1 if none
+ * @param decoder_ret if non-NULL, returns the decoder for the
+ * selected stream
+ * @param flags flags; none are currently defined
+ * @return the non-negative stream number in case of success,
+ * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
+ * could be found,
+ * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
+ * @note If av_find_best_stream returns successfully and decoder_ret is not
+ * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
+ */
+int av_find_best_stream(AVFormatContext *ic,
+ enum AVMediaType type,
+ int wanted_stream_nb,
+ int related_stream,
+ AVCodec **decoder_ret,
+ int flags);
+
+/**
+ * Return the next frame of a stream.
+ * This function returns what is stored in the file, and does not validate
+ * that what is there are valid frames for the decoder. It will split what is
+ * stored in the file into frames and return one for each call. It will not
+ * omit invalid data between valid frames so as to give the decoder the maximum
+ * information possible for decoding.
+ *
+ * If pkt->buf is NULL, then the packet is valid until the next
+ * av_read_frame() or until avformat_close_input(). Otherwise the packet
+ * is valid indefinitely. In both cases the packet must be freed with
+ * av_packet_unref when it is no longer needed. For video, the packet contains
+ * exactly one frame. For audio, it contains an integer number of frames if each
+ * frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames
+ * have a variable size (e.g. MPEG audio), then it contains one frame.
+ *
+ * pkt->pts, pkt->dts and pkt->duration are always set to correct
+ * values in AVStream.time_base units (and guessed if the format cannot
+ * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
+ * has B-frames, so it is better to rely on pkt->dts if you do not
+ * decompress the payload.
+ *
+ * @return 0 if OK, < 0 on error or end of file
+ */
+int av_read_frame(AVFormatContext *s, AVPacket *pkt);
+
+/**
+ * Seek to the keyframe at timestamp.
+ * 'timestamp' in 'stream_index'.
+ *
+ * @param s media file handle
+ * @param stream_index If stream_index is (-1), a default
+ * stream is selected, and timestamp is automatically converted
+ * from AV_TIME_BASE units to the stream specific time_base.
+ * @param timestamp Timestamp in AVStream.time_base units
+ * or, if no stream is specified, in AV_TIME_BASE units.
+ * @param flags flags which select direction and seeking mode
+ * @return >= 0 on success
+ */
+int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
+ int flags);
+
+/**
+ * Seek to timestamp ts.
+ * Seeking will be done so that the point from which all active streams
+ * can be presented successfully will be closest to ts and within min/max_ts.
+ * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
+ *
+ * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
+ * are the file position (this may not be supported by all demuxers).
+ * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
+ * in the stream with stream_index (this may not be supported by all demuxers).
+ * Otherwise all timestamps are in units of the stream selected by stream_index
+ * or if stream_index is -1, in AV_TIME_BASE units.
+ * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
+ * keyframes (this may not be supported by all demuxers).
+ * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
+ *
+ * @param s media file handle
+ * @param stream_index index of the stream which is used as time base reference
+ * @param min_ts smallest acceptable timestamp
+ * @param ts target timestamp
+ * @param max_ts largest acceptable timestamp
+ * @param flags flags
+ * @return >=0 on success, error code otherwise
+ *
+ * @note This is part of the new seek API which is still under construction.
+ * Thus do not use this yet. It may change at any time, do not expect
+ * ABI compatibility yet!
+ */
+int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
+
+/**
+ * Discard all internally buffered data. This can be useful when dealing with
+ * discontinuities in the byte stream. Generally works only with formats that
+ * can resync. This includes headerless formats like MPEG-TS/TS but should also
+ * work with NUT, Ogg and in a limited way AVI for example.
+ *
+ * The set of streams, the detected duration, stream parameters and codecs do
+ * not change when calling this function. If you want a complete reset, it's
+ * better to open a new AVFormatContext.
+ *
+ * This does not flush the AVIOContext (s->pb). If necessary, call
+ * avio_flush(s->pb) before calling this function.
+ *
+ * @param s media file handle
+ * @return >=0 on success, error code otherwise
+ */
+int avformat_flush(AVFormatContext *s);
+
+/**
+ * Start playing a network-based stream (e.g. RTSP stream) at the
+ * current position.
+ */
+int av_read_play(AVFormatContext *s);
+
+/**
+ * Pause a network-based stream (e.g. RTSP stream).
+ *
+ * Use av_read_play() to resume it.
+ */
+int av_read_pause(AVFormatContext *s);
+
+/**
+ * Close an opened input AVFormatContext. Free it and all its contents
+ * and set *s to NULL.
+ */
+void avformat_close_input(AVFormatContext **s);
+/**
+ * @}
+ */
+
+#define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
+#define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
+#define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
+#define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
+
+/**
+ * @addtogroup lavf_encoding
+ * @{
+ */
+/**
+ * Allocate the stream private data and write the stream header to
+ * an output media file.
+ *
+ * @param s Media file handle, must be allocated with avformat_alloc_context().
+ * Its oformat field must be set to the desired output format;
+ * Its pb field must be set to an already opened AVIOContext.
+ * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
+ * On return this parameter will be destroyed and replaced with a dict containing
+ * options that were not found. May be NULL.
+ *
+ * @return 0 on success, negative AVERROR on failure.
+ *
+ * @see av_opt_find, av_dict_set, avio_open, av_oformat_next.
+ */
+av_warn_unused_result
+int avformat_write_header(AVFormatContext *s, AVDictionary **options);
+
+/**
+ * Write a packet to an output media file.
+ *
+ * This function passes the packet directly to the muxer, without any buffering
+ * or reordering. The caller is responsible for correctly interleaving the
+ * packets if the format requires it. Callers that want libavformat to handle
+ * the interleaving should call av_interleaved_write_frame() instead of this
+ * function.
+ *
+ * @param s media file handle
+ * @param pkt The packet containing the data to be written. Note that unlike
+ * av_interleaved_write_frame(), this function does not take
+ * ownership of the packet passed to it (though some muxers may make
+ * an internal reference to the input packet).
+ * <br>
+ * This parameter can be NULL (at any time, not just at the end), in
+ * order to immediately flush data buffered within the muxer, for
+ * muxers that buffer up data internally before writing it to the
+ * output.
+ * <br>
+ * Packet's @ref AVPacket.stream_index "stream_index" field must be
+ * set to the index of the corresponding stream in @ref
+ * AVFormatContext.streams "s->streams".
+ * <br>
+ * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
+ * must be set to correct values in the stream's timebase (unless the
+ * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
+ * they can be set to AV_NOPTS_VALUE).
+ * The dts for subsequent packets passed to this function must be strictly
+ * increasing when compared in their respective timebases (unless the
+ * output format is flagged with the AVFMT_TS_NONSTRICT, then they
+ * merely have to be nondecreasing). @ref AVPacket.duration
+ * "duration") should also be set if known.
+ * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
+ *
+ * @see av_interleaved_write_frame()
+ */
+int av_write_frame(AVFormatContext *s, AVPacket *pkt);
+
+/**
+ * Write a packet to an output media file ensuring correct interleaving.
+ *
+ * This function will buffer the packets internally as needed to make sure the
+ * packets in the output file are properly interleaved in the order of
+ * increasing dts. Callers doing their own interleaving should call
+ * av_write_frame() instead of this function.
+ *
+ * @param s media file handle
+ * @param pkt The packet containing the data to be written.
+ * <br>
+ * If the packet is reference-counted, this function will take
+ * ownership of this reference and unreference it later when it sees
+ * fit.
+ * The caller must not access the data through this reference after
+ * this function returns. If the packet is not reference-counted,
+ * libavformat will make a copy.
+ * <br>
+ * This parameter can be NULL (at any time, not just at the end), to
+ * flush the interleaving queues.
+ * <br>
+ * Packet's @ref AVPacket.stream_index "stream_index" field must be
+ * set to the index of the corresponding stream in @ref
+ * AVFormatContext.streams "s->streams".
+ * <br>
+ * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
+ * must be set to correct values in the stream's timebase (unless the
+ * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
+ * they can be set to AV_NOPTS_VALUE).
+ * The dts for subsequent packets in one stream must be strictly
+ * increasing (unless the output format is flagged with the
+ * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
+ * @ref AVPacket.duration "duration") should also be set if known.
+ *
+ * @return 0 on success, a negative AVERROR on error. Libavformat will always
+ * take care of freeing the packet, even if this function fails.
+ *
+ * @see av_write_frame(), AVFormatContext.max_interleave_delta
+ */
+int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
+
+/**
+ * Write a uncoded frame to an output media file.
+ *
+ * The frame must be correctly interleaved according to the container
+ * specification; if not, then av_interleaved_write_frame() must be used.
+ *
+ * See av_interleaved_write_frame() for details.
+ */
+int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
+ AVFrame *frame);
+
+/**
+ * Write a uncoded frame to an output media file.
+ *
+ * If the muxer supports it, this function makes it possible to write an AVFrame
+ * structure directly, without encoding it into a packet.
+ * It is mostly useful for devices and similar special muxers that use raw
+ * video or PCM data and will not serialize it into a byte stream.
+ *
+ * To test whether it is possible to use it with a given muxer and stream,
+ * use av_write_uncoded_frame_query().
+ *
+ * The caller gives up ownership of the frame and must not access it
+ * afterwards.
+ *
+ * @return >=0 for success, a negative code on error
+ */
+int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index,
+ AVFrame *frame);
+
+/**
+ * Test whether a muxer supports uncoded frame.
+ *
+ * @return >=0 if an uncoded frame can be written to that muxer and stream,
+ * <0 if not
+ */
+int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
+
+/**
+ * Write the stream trailer to an output media file and free the
+ * file private data.
+ *
+ * May only be called after a successful call to avformat_write_header.
+ *
+ * @param s media file handle
+ * @return 0 if OK, AVERROR_xxx on error
+ */
+int av_write_trailer(AVFormatContext *s);
+
+/**
+ * Return the output format in the list of registered output formats
+ * which best matches the provided parameters, or return NULL if
+ * there is no match.
+ *
+ * @param short_name if non-NULL checks if short_name matches with the
+ * names of the registered formats
+ * @param filename if non-NULL checks if filename terminates with the
+ * extensions of the registered formats
+ * @param mime_type if non-NULL checks if mime_type matches with the
+ * MIME type of the registered formats
+ */
+AVOutputFormat *av_guess_format(const char *short_name,
+ const char *filename,
+ const char *mime_type);
+
+/**
+ * Guess the codec ID based upon muxer and filename.
+ */
+enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
+ const char *filename, const char *mime_type,
+ enum AVMediaType type);
+
+/**
+ * Get timing information for the data currently output.
+ * The exact meaning of "currently output" depends on the format.
+ * It is mostly relevant for devices that have an internal buffer and/or
+ * work in real time.
+ * @param s media file handle
+ * @param stream stream in the media file
+ * @param[out] dts DTS of the last packet output for the stream, in stream
+ * time_base units
+ * @param[out] wall absolute time when that packet whas output,
+ * in microsecond
+ * @return 0 if OK, AVERROR(ENOSYS) if the format does not support it
+ * Note: some formats or devices may not allow to measure dts and wall
+ * atomically.
+ */
+int av_get_output_timestamp(struct AVFormatContext *s, int stream,
+ int64_t *dts, int64_t *wall);
+
+
+/**
+ * @}
+ */
+
+
+/**
+ * @defgroup lavf_misc Utility functions
+ * @ingroup libavf
+ * @{
+ *
+ * Miscellaneous utility functions related to both muxing and demuxing
+ * (or neither).
+ */
+
+/**
+ * Send a nice hexadecimal dump of a buffer to the specified file stream.
+ *
+ * @param f The file stream pointer where the dump should be sent to.
+ * @param buf buffer
+ * @param size buffer size
+ *
+ * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
+ */
+void av_hex_dump(FILE *f, const uint8_t *buf, int size);
+
+/**
+ * Send a nice hexadecimal dump of a buffer to the log.
+ *
+ * @param avcl A pointer to an arbitrary struct of which the first field is a
+ * pointer to an AVClass struct.
+ * @param level The importance level of the message, lower values signifying
+ * higher importance.
+ * @param buf buffer
+ * @param size buffer size
+ *
+ * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
+ */
+void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
+
+/**
+ * Send a nice dump of a packet to the specified file stream.
+ *
+ * @param f The file stream pointer where the dump should be sent to.
+ * @param pkt packet to dump
+ * @param dump_payload True if the payload must be displayed, too.
+ * @param st AVStream that the packet belongs to
+ */
+void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st);
+
+
+/**
+ * Send a nice dump of a packet to the log.
+ *
+ * @param avcl A pointer to an arbitrary struct of which the first field is a
+ * pointer to an AVClass struct.
+ * @param level The importance level of the message, lower values signifying
+ * higher importance.
+ * @param pkt packet to dump
+ * @param dump_payload True if the payload must be displayed, too.
+ * @param st AVStream that the packet belongs to
+ */
+void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload,
+ const AVStream *st);
+
+/**
+ * Get the AVCodecID for the given codec tag tag.
+ * If no codec id is found returns AV_CODEC_ID_NONE.
+ *
+ * @param tags list of supported codec_id-codec_tag pairs, as stored
+ * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
+ * @param tag codec tag to match to a codec ID
+ */
+enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
+
+/**
+ * Get the codec tag for the given codec id id.
+ * If no codec tag is found returns 0.
+ *
+ * @param tags list of supported codec_id-codec_tag pairs, as stored
+ * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
+ * @param id codec ID to match to a codec tag
+ */
+unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
+
+/**
+ * Get the codec tag for the given codec id.
+ *
+ * @param tags list of supported codec_id - codec_tag pairs, as stored
+ * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
+ * @param id codec id that should be searched for in the list
+ * @param tag A pointer to the found tag
+ * @return 0 if id was not found in tags, > 0 if it was found
+ */
+int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
+ unsigned int *tag);
+
+int av_find_default_stream_index(AVFormatContext *s);
+
+/**
+ * Get the index for a specific timestamp.
+ *
+ * @param st stream that the timestamp belongs to
+ * @param timestamp timestamp to retrieve the index for
+ * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
+ * to the timestamp which is <= the requested one, if backward
+ * is 0, then it will be >=
+ * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
+ * @return < 0 if no such timestamp could be found
+ */
+int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
+
+/**
+ * Add an index entry into a sorted list. Update the entry if the list
+ * already contains it.
+ *
+ * @param timestamp timestamp in the time base of the given stream
+ */
+int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
+ int size, int distance, int flags);
+
+
+/**
+ * Split a URL string into components.
+ *
+ * The pointers to buffers for storing individual components may be null,
+ * in order to ignore that component. Buffers for components not found are
+ * set to empty strings. If the port is not found, it is set to a negative
+ * value.
+ *
+ * @param proto the buffer for the protocol
+ * @param proto_size the size of the proto buffer
+ * @param authorization the buffer for the authorization
+ * @param authorization_size the size of the authorization buffer
+ * @param hostname the buffer for the host name
+ * @param hostname_size the size of the hostname buffer
+ * @param port_ptr a pointer to store the port number in
+ * @param path the buffer for the path
+ * @param path_size the size of the path buffer
+ * @param url the URL to split
+ */
+void av_url_split(char *proto, int proto_size,
+ char *authorization, int authorization_size,
+ char *hostname, int hostname_size,
+ int *port_ptr,
+ char *path, int path_size,
+ const char *url);
+
+
+/**
+ * Print detailed information about the input or output format, such as
+ * duration, bitrate, streams, container, programs, metadata, side data,
+ * codec and time base.
+ *
+ * @param ic the context to analyze
+ * @param index index of the stream to dump information about
+ * @param url the URL to print, such as source or destination file
+ * @param is_output Select whether the specified context is an input(0) or output(1)
+ */
+void av_dump_format(AVFormatContext *ic,
+ int index,
+ const char *url,
+ int is_output);
+
+/**
+ * Return in 'buf' the path with '%d' replaced by a number.
+ *
+ * Also handles the '%0nd' format where 'n' is the total number
+ * of digits and '%%'.
+ *
+ * @param buf destination buffer
+ * @param buf_size destination buffer size
+ * @param path numbered sequence string
+ * @param number frame number
+ * @return 0 if OK, -1 on format error
+ */
+int av_get_frame_filename(char *buf, int buf_size,
+ const char *path, int number);
+
+/**
+ * Check whether filename actually is a numbered sequence generator.
+ *
+ * @param filename possible numbered sequence string
+ * @return 1 if a valid numbered sequence string, 0 otherwise
+ */
+int av_filename_number_test(const char *filename);
+
+/**
+ * Generate an SDP for an RTP session.
+ *
+ * Note, this overwrites the id values of AVStreams in the muxer contexts
+ * for getting unique dynamic payload types.
+ *
+ * @param ac array of AVFormatContexts describing the RTP streams. If the
+ * array is composed by only one context, such context can contain
+ * multiple AVStreams (one AVStream per RTP stream). Otherwise,
+ * all the contexts in the array (an AVCodecContext per RTP stream)
+ * must contain only one AVStream.
+ * @param n_files number of AVCodecContexts contained in ac
+ * @param buf buffer where the SDP will be stored (must be allocated by
+ * the caller)
+ * @param size the size of the buffer
+ * @return 0 if OK, AVERROR_xxx on error
+ */
+int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
+
+/**
+ * Return a positive value if the given filename has one of the given
+ * extensions, 0 otherwise.
+ *
+ * @param filename file name to check against the given extensions
+ * @param extensions a comma-separated list of filename extensions
+ */
+int av_match_ext(const char *filename, const char *extensions);
+
+/**
+ * Test if the given container can store a codec.
+ *
+ * @param ofmt container to check for compatibility
+ * @param codec_id codec to potentially store in container
+ * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
+ *
+ * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
+ * A negative number if this information is not available.
+ */
+int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id,
+ int std_compliance);
+
+/**
+ * @defgroup riff_fourcc RIFF FourCCs
+ * @{
+ * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
+ * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
+ * following code:
+ * @code
+ * uint32_t tag = MKTAG('H', '2', '6', '4');
+ * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
+ * enum AVCodecID id = av_codec_get_id(table, tag);
+ * @endcode
+ */
+/**
+ * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
+ */
+const struct AVCodecTag *avformat_get_riff_video_tags(void);
+/**
+ * @return the table mapping RIFF FourCCs for audio to AVCodecID.
+ */
+const struct AVCodecTag *avformat_get_riff_audio_tags(void);
+/**
+ * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
+ */
+const struct AVCodecTag *avformat_get_mov_video_tags(void);
+/**
+ * @return the table mapping MOV FourCCs for audio to AVCodecID.
+ */
+const struct AVCodecTag *avformat_get_mov_audio_tags(void);
+
+/**
+ * @}
+ */
+
+/**
+ * Guess the sample aspect ratio of a frame, based on both the stream and the
+ * frame aspect ratio.
+ *
+ * Since the frame aspect ratio is set by the codec but the stream aspect ratio
+ * is set by the demuxer, these two may not be equal. This function tries to
+ * return the value that you should use if you would like to display the frame.
+ *
+ * Basic logic is to use the stream aspect ratio if it is set to something sane
+ * otherwise use the frame aspect ratio. This way a container setting, which is
+ * usually easy to modify can override the coded value in the frames.
+ *
+ * @param format the format context which the stream is part of
+ * @param stream the stream which the frame is part of
+ * @param frame the frame with the aspect ratio to be determined
+ * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
+ */
+AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, AVFrame *frame);
+
+/**
+ * Guess the frame rate, based on both the container and codec information.
+ *
+ * @param ctx the format context which the stream is part of
+ * @param stream the stream which the frame is part of
+ * @param frame the frame for which the frame rate should be determined, may be NULL
+ * @return the guessed (valid) frame rate, 0/1 if no idea
+ */
+AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, AVFrame *frame);
+
+/**
+ * Check if the stream st contained in s is matched by the stream specifier
+ * spec.
+ *
+ * See the "stream specifiers" chapter in the documentation for the syntax
+ * of spec.
+ *
+ * @return >0 if st is matched by spec;
+ * 0 if st is not matched by spec;
+ * AVERROR code if spec is invalid
+ *
+ * @note A stream specifier can match several streams in the format.
+ */
+int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st,
+ const char *spec);
+
+int avformat_queue_attached_pictures(AVFormatContext *s);
+
+/**
+ * Apply a list of bitstream filters to a packet.
+ *
+ * @param codec AVCodecContext, usually from an AVStream
+ * @param pkt the packet to apply filters to
+ * @param bsfc a NULL-terminated list of filters to apply
+ * @return >=0 on success;
+ * AVERROR code on failure
+ */
+int av_apply_bitstream_filters(AVCodecContext *codec, AVPacket *pkt,
+ AVBitStreamFilterContext *bsfc);
+
+/**
+ * @}
+ */
+
+#endif /* AVFORMAT_AVFORMAT_H */
projects / rtmpclient.git / blobdiff