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       /*
        * 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
       /**
        * I return the LIBAVFORMAT_VERSION_INT constant.  You got
        * a fucking problem with that, douchebag?
        */
       unsigned avformat_version(void);
       /**
        * Return the libavformat build-time configuration.
        */
       const char *avformat_configuration(void);
       /**
        * Return the libavformat license.
        */
       const char *avformat_license(void);
       #include <time.h>
       #include <stdio.h>  /* FILE */
       #include "libavcodec/avcodec.h"
       #include "avio.h"
       #include "libavformat/version.h"
       struct AVFormatContext;
       /*
        * Public Metadata API.
        * The metadata API allows libavformat to export metadata tags to a client
        * application using a sequence of key/value pairs. Like all strings in FFmpeg,
        * metadata must be stored as 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:
        * 1. 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.
        * 2. 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.
        * 3. 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.
        *    a) 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.
        *    b) 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".
+       *
        * 4. 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:
+       *
        * 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.
        * 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.
        */
       #define AV_METADATA_MATCH_CASE      1
       #define AV_METADATA_IGNORE_SUFFIX   2
       #define AV_METADATA_DONT_STRDUP_KEY 4
       #define AV_METADATA_DONT_STRDUP_VAL 8
       #define AV_METADATA_DONT_OVERWRITE 16   ///< Don't overwrite existing tags.
       typedef struct {
           char *key;
           char *value;
       }AVMetadataTag;
       typedef struct AVMetadata AVMetadata;
       #if FF_API_OLD_METADATA
       typedef struct AVMetadataConv AVMetadataConv;
       #endif
       /**
        * Get a metadata element with matching key.
+       *
        * @param prev Set to the previous matching element to find the next.
        *             If set to NULL the first matching element is returned.
        * @param flags Allows case as well as suffix-insensitive comparisons.
        * @return Found tag or NULL, changing key or value leads to undefined behavior.
        */
       AVMetadataTag *
       av_metadata_get(AVMetadata *m, const char *key, const AVMetadataTag *prev, int flags);
       #if FF_API_OLD_METADATA
       /**
        * Set the given tag in *pm, overwriting an existing tag.
+       *
        * @param pm pointer to a pointer to a metadata struct. If *pm is NULL
        * a metadata struct is allocated and put in *pm.
        * @param key tag key to add to *pm (will be av_strduped)
        * @param value tag value to add to *pm (will be av_strduped)
        * @return >= 0 on success otherwise an error code <0
        * @deprecated Use av_metadata_set2() instead.
        */
       attribute_deprecated int av_metadata_set(AVMetadata **pm, const char *key, const char *value);
       #endif
       /**
        * Set the given tag in *pm, overwriting an existing tag.
+       *
        * @param pm pointer to a pointer to a metadata struct. If *pm is NULL
        * a metadata struct is allocated and put in *pm.
        * @param key tag key to add to *pm (will be av_strduped depending on flags)
        * @param value tag value to add to *pm (will be av_strduped depending on flags).
        *        Passing a NULL value will cause an existing tag to be deleted.
        * @return >= 0 on success otherwise an error code <0
        */
       int av_metadata_set2(AVMetadata **pm, const char *key, const char *value, int flags);
       #if FF_API_OLD_METADATA
       /**
        * This function is provided for compatibility reason and currently does nothing.
        */
       attribute_deprecated void av_metadata_conv(struct AVFormatContext *ctx, const AVMetadataConv *d_conv,
                                                                               const AVMetadataConv *s_conv);
       #endif
       /**
        * Copy metadata from one AVMetadata struct into another.
        * @param dst pointer to a pointer to a AVMetadata struct. If *dst is NULL,
        *            this function will allocate a struct for you and put it in *dst
        * @param src pointer to source AVMetadata struct
        * @param flags flags to use when setting metadata in *dst
        * @note metadata is read using the AV_METADATA_IGNORE_SUFFIX flag
        */
       void av_metadata_copy(AVMetadata **dst, AVMetadata *src, int flags);
       /**
        * Free all the memory allocated for an AVMetadata struct.
        */
       void av_metadata_free(AVMetadata **m);
       /* packet functions */
       /**
        * Allocate and read the payload of a packet and initialize its
        * fields with default values.
+       *
        * @param pkt packet
        * @param size desired payload size
        * @return >0 (read size) if OK, AVERROR_xxx otherwise
        */
       int av_get_packet(ByteIOContext *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 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(ByteIOContext *s, AVPacket *pkt, int size);
       /*************************************************/
       /* 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;
       /*************************************************/
       /* 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 */
       } AVProbeData;
       #define AVPROBE_SCORE_MAX 100               ///< maximum score, half of that is used for file-extension-based detection
       #define AVPROBE_PADDING_SIZE 32             ///< extra allocated bytes at the end of the probe buffer
       typedef struct AVFormatParameters {
           AVRational time_base;
           int sample_rate;
           int channels;
           int width;
           int height;
           enum PixelFormat pix_fmt;
           int channel; /**< Used to select DV channel. */
           const char *standard; /**< TV standard, NTSC, PAL, SECAM */
           unsigned int mpeg2ts_raw:1;  /**< Force raw MPEG-2 transport stream output, if possible. */
           unsigned int mpeg2ts_compute_pcr:1; /**< Compute exact PCR for each transport
                                                   stream packet (only meaningful if
                                                   mpeg2ts_raw is TRUE). */
           unsigned int initial_pause:1;       /**< Do not begin to play the stream
                                                   immediately (RTSP only). */
           unsigned int prealloced_context:1;
       #if FF_API_PARAMETERS_CODEC_ID
           attribute_deprecated enum CodecID video_codec_id;
           attribute_deprecated enum CodecID audio_codec_id;
       #endif
       } AVFormatParameters;
       //! Demuxer will use url_fopen, 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. */
       #define AVFMT_RAWPICTURE    0x0020 /**< Format wants AVPicture structure for
                                             raw picture data. */
       #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 */
       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 */
           /**
            * size of private data so that it can be allocated in the wrapper
            */
           int priv_data_size;
           /* output support */
           enum CodecID audio_codec; /**< default audio codec */
           enum CodecID video_codec; /**< default video codec */
           int (*write_header)(struct AVFormatContext *);
           int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
           int (*write_trailer)(struct AVFormatContext *);
           /**
            * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER
            */
           int flags;
           /**
            * Currently only used to set pixel format if not YUV420P.
            */
           int (*set_parameters)(struct AVFormatContext *, AVFormatParameters *);
           int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
                                    AVPacket *in, int flush);
           /**
            * List of supported codec_id-codec_tag pairs, ordered by "better
            * choice first". The arrays are all terminated by CODEC_ID_NONE.
            */
           const struct AVCodecTag * const *codec_tag;
           enum CodecID subtitle_codec; /**< default subtitle codec */
       #if FF_API_OLD_METADATA
           const AVMetadataConv *metadata_conv;
       #endif
           const AVClass *priv_class; ///< AVClass for the private context
           /* private fields */
           struct AVOutputFormat *next;
       } AVOutputFormat;
       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;
           /**
            * 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. 'ap' if non-NULL contains
            * additional parameters. Only used in raw format right
            * now. 'av_new_stream' should be called to create new streams.
            */
           int (*read_header)(struct AVFormatContext *,
                              AVFormatParameters *ap);
           /**
            * Read one packet and put it in 'pkt'. pts and flags are also
            * set. 'av_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 *);
       #if FF_API_READ_SEEK
           /**
            * 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)
            */
           attribute_deprecated int (*read_seek)(struct AVFormatContext *,
                                                 int stream_index, int64_t timestamp, int flags);
       #endif
           /**
            * Gets 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);
           /**
            * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER.
            */
           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;
           /**
            * General purpose read-only value that the format can use.
            */
           int value;
           /**
            * 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 *);
           const struct AVCodecTag * const *codec_tag;
           /**
            * 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);
       #if FF_API_OLD_METADATA
           const AVMetadataConv *metadata_conv;
       #endif
           /* private fields */
           struct AVInputFormat *next;
       } 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 */
       };
       typedef struct AVIndexEntry {
           int64_t pos;
           int64_t timestamp;
       #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
       /**
        * 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 */
           int id;       /**< format-specific stream ID */
           AVCodecContext *codec; /**< codec context */
           /**
            * 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.
            */
           AVRational r_frame_rate;
           void *priv_data;
           /* internal data used in av_find_stream_info() */
           int64_t first_dts;
           /**
            * encoding: pts generation when outputting stream
            */
           struct AVFrac pts;
           /**
            * This is the fundamental unit of time (in seconds) in terms
            * of which frame timestamps are represented. For fixed-fps content,
            * time base should be 1/framerate and timestamp increments should be 1.
            */
           AVRational time_base;
           int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
           /* ffmpeg.c private use */
           int stream_copy; /**< If set, just copy stream. */
           enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
           //FIXME move stuff to a flags field?
           /**
            * Quality, as it has been removed from AVCodecContext and put in AVVideoFrame.
            * MN: dunno if that is the right place for it
            */
           float quality;
           /**
            * Decoding: pts of the first frame of the stream, 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;
       #if FF_API_OLD_METADATA
           attribute_deprecated char language[4]; /**< ISO 639-2/B 3-letter language code (empty string if undefined) */
       #endif
           /* av_read_frame() support */
           enum AVStreamParseType need_parsing;
           struct AVCodecParserContext *parser;
           int64_t cur_dts;
           int last_IP_duration;
           int64_t last_IP_pts;
           /* av_seek_frame() support */
           AVIndexEntry *index_entries; /**< Only used if the format does not
                                           support seeking natively. */
           int nb_index_entries;
           unsigned int index_entries_allocated_size;
           int64_t nb_frames;                 ///< number of frames in this stream if known or 0
       #if FF_API_LAVF_UNUSED
           attribute_deprecated int64_t unused[4+1];
       #endif
       #if FF_API_OLD_METADATA
           attribute_deprecated char *filename; /**< source filename of the stream */
       #endif
           int disposition; /**< AV_DISPOSITION_* bit field */
           AVProbeData probe_data;
       #define MAX_REORDER_DELAY 16
           int64_t pts_buffer[MAX_REORDER_DELAY+1];
           /**
            * sample aspect ratio (0 if unknown)
            * - encoding: Set by user.
            * - decoding: Set by libavformat.
            */
           AVRational sample_aspect_ratio;
           AVMetadata *metadata;
           /* Intended mostly for av_read_frame() support. Not supposed to be used by */
           /* external applications; try to use something else if at all possible.    */
           const uint8_t *cur_ptr;
           int cur_len;
           AVPacket cur_pkt;
           // 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 reference_dts;
           /**
            * Number of packets to buffer for codec probing
            * NOT PART OF PUBLIC API
            */
       #define MAX_PROBE_PACKETS 2500
           int probe_packets;
           /**
            * last packet in packet_buffer for this stream when muxing.
            * used internally, NOT PART OF PUBLIC API, dont read or write from outside of libav*
            */
           struct AVPacketList *last_in_packet_buffer;
           /**
            * Average framerate
            */
           AVRational avg_frame_rate;
           /**
            * Number of frames that have been demuxed during av_find_stream_info()
            */
           int codec_info_nb_frames;
           /**
            * Stream informations used internally by av_find_stream_info()
            */
       #define MAX_STD_TIMEBASES (60*12+5)
           struct {
               int64_t last_dts;
               int64_t duration_gcd;
               int duration_count;
               double duration_error[MAX_STD_TIMEBASES];
               int64_t codec_info_duration;
           } *info;
       } AVStream;
       #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;
       #if FF_API_OLD_METADATA
           attribute_deprecated char           *provider_name; ///< network name for DVB streams
           attribute_deprecated char           *name;          ///< service name for DVB streams
       #endif
           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;
           AVMetadata *metadata;
       } 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
       #if FF_API_OLD_METADATA
           attribute_deprecated char *title;            ///< chapter title
       #endif
           AVMetadata *metadata;
       } AVChapter;
       #if FF_API_MAX_STREAMS
       #define MAX_STREAMS 20
       #endif
       /**
        * 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*.
        */
       typedef struct AVFormatContext {
           const AVClass *av_class; /**< Set by avformat_alloc_context. */
           /* Can only be iformat or oformat, not both at the same time. */
           struct AVInputFormat *iformat;
           struct AVOutputFormat *oformat;
           void *priv_data;
           ByteIOContext *pb;
           unsigned int nb_streams;
       #if FF_API_MAX_STREAMS
           AVStream *streams[MAX_STREAMS];
       #else
           AVStream **streams;
       #endif
           char filename[1024]; /**< input or output filename */
           /* stream info */
           int64_t timestamp;
       #if FF_API_OLD_METADATA
           attribute_deprecated char title[512];
           attribute_deprecated char author[512];
           attribute_deprecated char copyright[512];
           attribute_deprecated char comment[512];
           attribute_deprecated char album[512];
           attribute_deprecated int year;  /**< ID3 year, 0 if none */
           attribute_deprecated int track; /**< track number, 0 if none */
           attribute_deprecated char genre[32]; /**< ID3 genre */
       #endif
           int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
           /* private data for pts handling (do not modify directly). */
           /**
            * This buffer is only needed when packets were already buffered but
            * not decoded, for example to get the codec parameters in MPEG
            * streams.
            */
           struct AVPacketList *packet_buffer;
           /**
            * Decoding: 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.
            */
           int64_t start_time;
           /**
            * Decoding: 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 dont set any of them. This is deduced from the
            * AVStream values if not set.
            */
           int64_t duration;
           /**
            * decoding: total file size, 0 if unknown
            */
           int64_t file_size;
           /**
            * Decoding: 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.
            */
           int bit_rate;
           /* av_read_frame() support */
           AVStream *cur_st;
       #if FF_API_LAVF_UNUSED
           const uint8_t *cur_ptr_deprecated;
           int cur_len_deprecated;
           AVPacket cur_pkt_deprecated;
       #endif
           /* av_seek_frame() support */
           int64_t data_offset; /**< offset of the first packet */
           int index_built;
           int mux_rate;
           unsigned int packet_size;
           int preload;
           int max_delay;
       #define AVFMT_NOOUTPUTLOOP -1
       #define AVFMT_INFINITEOUTPUTLOOP 0
           /**
            * number of times to loop output in formats that support it
            */
           int loop_output;
           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_RTP_HINT     0x0040 ///< Add RTP hinting to the output file
           int loop_input;
           /**
            * decoding: size of data to probe; encoding: unused.
            */
           unsigned int probesize;
           /**
            * Maximum time (in AV_TIME_BASE units) during which the input should
            * be analyzed in av_find_stream_info().
            */
           int max_analyze_duration;
           const uint8_t *key;
           int keylen;
           unsigned int nb_programs;
           AVProgram **programs;
           /**
            * Forced video codec_id.
            * Demuxing: Set by user.
            */
           enum CodecID video_codec_id;
           /**
            * Forced audio codec_id.
            * Demuxing: Set by user.
            */
           enum CodecID audio_codec_id;
           /**
            * Forced subtitle codec_id.
            * Demuxing: Set by user.
            */
           enum CodecID 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;
           unsigned int nb_chapters;
           AVChapter **chapters;
           /**
            * Flags to enable debugging.
            */
           int debug;
       #define FF_FDEBUG_TS        0x0001
           /**
            * Raw packets from the demuxer, prior to parsing and decoding.
            * This buffer is used for buffering packets until the codec can
            * be identified, as parsing cannot be done without knowing the
            * codec.
            */
           struct AVPacketList *raw_packet_buffer;
           struct AVPacketList *raw_packet_buffer_end;
           struct AVPacketList *packet_buffer_end;
           AVMetadata *metadata;
           /**
            * Remaining size available for raw_packet_buffer, in bytes.
            * NOT PART OF PUBLIC API
            */
       #define RAW_PACKET_BUFFER_SIZE 2500000
           int raw_packet_buffer_remaining_size;
           /**
            * 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.
            * - encoding: Set by user.
            * - decoding: Unused.
            */
           int64_t start_time_realtime;
       } AVFormatContext;
       typedef struct AVPacketList {
           AVPacket pkt;
           struct AVPacketList *next;
       } AVPacketList;
       #if FF_API_FIRST_FORMAT
       attribute_deprecated extern AVInputFormat *first_iformat;
       attribute_deprecated extern AVOutputFormat *first_oformat;
       #endif
       /**
        * 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(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(AVOutputFormat *f);
       enum CodecID av_guess_image2_codec(const char *filename);
       /* XXX: Use automatic init with either ELF sections or C file parser */
       /* modules. */
       /* utils.c */
       void av_register_input_format(AVInputFormat *format);
       void av_register_output_format(AVOutputFormat *format);
       #if FF_API_GUESS_FORMAT
       attribute_deprecated AVOutputFormat *guess_stream_format(const char *short_name,
                                           const char *filename,
                                           const char *mime_type);
       /**
        * @deprecated Use av_guess_format() instead.
        */
       attribute_deprecated AVOutputFormat *guess_format(const char *short_name,
                                                         const char *filename,
                                                         const char *mime_type);
       #endif
       /**
        * 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 CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
                                   const char *filename, const char *mime_type,
                                   enum AVMediaType type);
       /**
        * 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_dump, av_pkt_dump_log
        */
       void av_hex_dump(FILE *f, 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_dump, av_pkt_dump_log
        */
       void av_hex_dump_log(void *avcl, int level, 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.
        */
       void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
       /**
        * 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.
        */
       void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt, int dump_payload);
       /**
        * 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()
        * @see av_register_protocol()
        */
       void av_register_all(void);
       /**
        * Get the CodecID for the given codec tag tag.
        * If no codec id is found returns CODEC_ID_NONE.
+       *
        * @param tags list of supported codec_id-codec_tag pairs, as stored
        * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
        */
       enum CodecID 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
        */
       unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum CodecID id);
       /* media file input */
       /**
        * 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 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 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);
       /**
        * Allocate all the structures needed to read an input stream.
        *        This does not open the needed codecs for decoding the stream[s].
        */
       int av_open_input_stream(AVFormatContext **ic_ptr,
                                ByteIOContext *pb, const char *filename,
                                AVInputFormat *fmt, AVFormatParameters *ap);
       /**
        * Open a media file as input. The codecs are not opened. Only the file
        * header (if present) is read.
+       *
        * @param ic_ptr The opened media file handle is put here.
        * @param filename filename to open
        * @param fmt If non-NULL, force the file format to use.
        * @param buf_size optional buffer size (zero if default is OK)
        * @param ap Additional parameters needed when opening the file
        *           (NULL if default).
        * @return 0 if OK, AVERROR_xxx otherwise
        */
       int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
                              AVInputFormat *fmt,
                              int buf_size,
                              AVFormatParameters *ap);
       #if FF_API_ALLOC_FORMAT_CONTEXT
       /**
        * @deprecated Use avformat_alloc_context() instead.
        */
       attribute_deprecated AVFormatContext *av_alloc_format_context(void);
       #endif
       /**
        * Allocate an AVFormatContext.
        * Can be freed with av_free() but do not forget to free everything you
        * explicitly allocated as well!
        */
       AVFormatContext *avformat_alloc_context(void);
       /**
        * 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
        * @return >=0 if OK, AVERROR_xxx on error
        * @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 av_find_stream_info(AVFormatContext *ic);
       /**
        * 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);
       /**
        * Read a transport packet from a media file.
+       *
        * This function is obsolete and should never be used.
        * Use av_read_frame() instead.
+       *
        * @param s media file handle
        * @param pkt is filled
        * @return 0 if OK, AVERROR_xxx on error
        */
       int av_read_packet(AVFormatContext *s, AVPacket *pkt);
       /**
        * 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.
+       *
        * The returned packet is valid
        * until the next av_read_frame() or until av_close_input_file() and
        * must be freed with av_free_packet. 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 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).
+       *
        * @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);
       /**
        * 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);
       /**
        * Free a AVFormatContext allocated by av_open_input_stream.
        * @param s context to free
        */
       void av_close_input_stream(AVFormatContext *s);
       /**
        * Close a media file (but not its codecs).
+       *
        * @param s media file handle
        */
       void av_close_input_file(AVFormatContext *s);
       /**
        * Add a new stream to a media file.
+       *
        * Can only be called in the read_header() function. If the flag
        * AVFMTCTX_NOHEADER is in the format context, then new streams
        * can be added in read_packet too.
+       *
        * @param s media file handle
        * @param id file-format-dependent stream ID
        */
       AVStream *av_new_stream(AVFormatContext *s, int id);
       AVProgram *av_new_program(AVFormatContext *s, int id);
       /**
        * Add a new chapter.
        * This function is NOT part of the public API
        * and should ONLY be used by demuxers.
+       *
        * @param s media file handle
        * @param id unique ID for this chapter
        * @param start chapter start time in time_base units
        * @param end chapter end time in time_base units
        * @param title chapter title
+       *
        * @return AVChapter or NULL on error
        */
       AVChapter *ff_new_chapter(AVFormatContext *s, int id, AVRational time_base,
                                 int64_t start, int64_t end, const char *title);
       /**
        * Set the pts for a given stream.
+       *
        * @param s stream
        * @param pts_wrap_bits number of bits effectively used by the pts
        *        (used for wrap control, 33 is the value for MPEG)
        * @param pts_num numerator to convert to seconds (MPEG: 1)
        * @param pts_den denominator to convert to seconds (MPEG: 90000)
        */
       void av_set_pts_info(AVStream *s, int pts_wrap_bits,
                            unsigned int pts_num, unsigned int pts_den);
       #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
       int av_find_default_stream_index(AVFormatContext *s);
       /**
        * Get the index for a specific timestamp.
        * @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);
       /**
        * Ensure the index uses less memory than the maximum specified in
        * AVFormatContext.max_index_size by discarding entries if it grows
        * too large.
        * This function is not part of the public API and should only be called
        * by demuxers.
        */
       void ff_reduce_index(AVFormatContext *s, int stream_index);
       /**
        * 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);
       /**
        * Perform a binary search using av_index_search_timestamp() and
        * AVInputFormat.read_timestamp().
        * This is not supposed to be called directly by a user application,
        * but by demuxers.
        * @param target_ts target timestamp in the time base of the given stream
        * @param stream_index stream number
        */
       int av_seek_frame_binary(AVFormatContext *s, int stream_index,
                                int64_t target_ts, int flags);
       /**
        * Update cur_dts of all streams based on the given timestamp and AVStream.
+       *
        * Stream ref_st unchanged, others set cur_dts in their native time base.
        * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
        * @param timestamp new dts expressed in time_base of param ref_st
        * @param ref_st reference stream giving time_base of param timestamp
        */
       void av_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
       /**
        * Perform a binary search using read_timestamp().
        * This is not supposed to be called directly by a user application,
        * but by demuxers.
        * @param target_ts target timestamp in the time base of the given stream
        * @param stream_index stream number
        */
       int64_t av_gen_search(AVFormatContext *s, int stream_index,
                             int64_t target_ts, int64_t pos_min,
                             int64_t pos_max, int64_t pos_limit,
                             int64_t ts_min, int64_t ts_max,
                             int flags, int64_t *ts_ret,
                             int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
       /**
        * media file output
        */
       int av_set_parameters(AVFormatContext *s, AVFormatParameters *ap);
       /**
        * 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);
       /**
        * Allocate the stream private data and write the stream header to an
        * output media file.
+       *
        * @param s media file handle
        * @return 0 if OK, AVERROR_xxx on error
        */
       int av_write_header(AVFormatContext *s);
       /**
        * Write a packet to an output media file.
+       *
        * The packet shall contain one audio or video frame.
        * The packet must be correctly interleaved according to the container
        * specification, if not then av_interleaved_write_frame must be used.
+       *
        * @param s media file handle
        * @param pkt The packet, which contains the stream_index, buf/buf_size,
                     dts/pts, ...
        * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
        */
       int av_write_frame(AVFormatContext *s, AVPacket *pkt);
       /**
        * Write a packet to an output media file ensuring correct interleaving.
+       *
        * The packet must contain one audio or video frame.
        * If the packets are already correctly interleaved, the application should
        * call av_write_frame() instead as it is slightly faster. It is also important
        * to keep in mind that completely non-interleaved input will need huge amounts
        * of memory to interleave with this, so it is preferable to interleave at the
        * demuxer level.
+       *
        * @param s media file handle
        * @param pkt The packet, which contains the stream_index, buf/buf_size,
                     dts/pts, ...
        * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
        */
       int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
       /**
        * Interleave a packet per dts in an output media file.
+       *
        * Packets with pkt->destruct == av_destruct_packet will be freed inside this
        * function, so they cannot be used after it. Note that calling av_free_packet()
        * on them is still safe.
+       *
        * @param s media file handle
        * @param out the interleaved packet will be output here
        * @param pkt the input packet
        * @param flush 1 if no further packets are available as input and all
        *              remaining packets should be output
        * @return 1 if a packet was output, 0 if no packet could be output,
        *         < 0 if an error occurred
        */
       int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
                                        AVPacket *pkt, int flush);
       /**
        * Write the stream trailer to an output media file and free the
        * file private data.
+       *
        * May only be called after a successful call to av_write_header.
+       *
        * @param s media file handle
        * @return 0 if OK, AVERROR_xxx on error
        */
       int av_write_trailer(AVFormatContext *s);
       void dump_format(AVFormatContext *ic,
                        int index,
                        const char *url,
                        int is_output);
       #if FF_API_PARSE_FRAME_PARAM
       /**
        * Parse width and height out of string str.
        * @deprecated Use av_parse_video_frame_size instead.
        */
       attribute_deprecated int parse_image_size(int *width_ptr, int *height_ptr,
                                                 const char *str);
       /**
        * Convert framerate from a string to a fraction.
        * @deprecated Use av_parse_video_frame_rate instead.
        */
       attribute_deprecated int parse_frame_rate(int *frame_rate, int *frame_rate_base,
                                                 const char *arg);
       #endif
       /**
        * Parse datestr and return a corresponding number of microseconds.
        * @param datestr String representing a date or a duration.
        * - If a date the syntax is:
        * @code
        *  now|{[{YYYY-MM-DD|YYYYMMDD}[T|t| ]]{{HH[:MM[:SS[.m...]]]}|{HH[MM[SS[.m...]]]}}[Z|z]}
        * @endcode
        * If the value is "now" it takes the current time.
        * Time is local time unless Z is appended, in which case it is
        * interpreted as UTC.
        * If the year-month-day part is not specified it takes the current
        * year-month-day.
        * @return the number of microseconds since 1st of January, 1970 up to
        * the time of the parsed date or INT64_MIN if datestr cannot be
        * successfully parsed.
        * - If a duration the syntax is:
        * @code
        *  [-]HH[:MM[:SS[.m...]]]
        *  [-]S+[.m...]
        * @endcode
        * @return the number of microseconds contained in a time interval
        * with the specified duration or INT64_MIN if datestr cannot be
        * successfully parsed.
        * @param duration Flag which tells how to interpret datestr, if
        * not zero datestr is interpreted as a duration, otherwise as a
        * date.
        */
       int64_t parse_date(const char *datestr, int duration);
       /**
        * Get the current time in microseconds.
        */
       int64_t av_gettime(void);
       /* ffm-specific for ffserver */
       #define FFM_PACKET_SIZE 4096
       int64_t ffm_read_write_index(int fd);
       int ffm_write_write_index(int fd, int64_t pos);
       void ffm_set_write_index(AVFormatContext *s, int64_t pos, int64_t file_size);
       /**
        * Attempt to find a specific tag in a URL.
+       *
        * syntax: '?tag1=val1&tag2=val2...'. Little URL decoding is done.
        * Return 1 if found.
        */
       int find_info_tag(char *arg, int arg_size, const char *tag1, const char *info);
       /**
        * 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.
+       *
        * @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 buff 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 avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size);
       /**
        * Return a positive value if the given filename has one of the given
        * extensions, 0 otherwise.
+       *
        * @param extensions a comma-separated list of filename extensions
        */
       int av_match_ext(const char *filename, const char *extensions);
       #endif /* AVFORMAT_AVFORMAT_H */