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/*
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 * copyright (c) 2001 Fabrice Bellard
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#ifndef FFMPEG_AVFORMAT_H
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#define FFMPEG_AVFORMAT_H
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#define LIBAVFORMAT_VERSION_INT ((52<<16)+(5<<8)+0)
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#define LIBAVFORMAT_VERSION     52.5.0
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#define LIBAVFORMAT_BUILD       LIBAVFORMAT_VERSION_INT
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#define LIBAVFORMAT_IDENT       "Lavf" AV_STRINGIFY(LIBAVFORMAT_VERSION)
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#include <time.h>
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#include <stdio.h>  /* FILE */
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#include "avcodec.h"
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#include "avio.h"
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/* packet functions */
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typedef struct AVPacket {
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    int64_t pts;                            ///< presentation time stamp in time_base units
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    int64_t dts;                            ///< decompression time stamp in time_base units
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    uint8_t *data;
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    int   size;
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    int   stream_index;
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    int   flags;
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    int   duration;                         ///< presentation duration in time_base units (0 if not available)
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    void  (*destruct)(struct AVPacket *);
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    void  *priv;
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    int64_t pos;                            ///< byte position in stream, -1 if unknown
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} AVPacket;
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#define PKT_FLAG_KEY   0x0001
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void av_destruct_packet_nofree(AVPacket *pkt);
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/**
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 * Default packet destructor.
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 */
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void av_destruct_packet(AVPacket *pkt);
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/**
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 * Initialize optional fields of a packet to default values.
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 *
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 * @param pkt packet
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 */
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void av_init_packet(AVPacket *pkt);
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/**
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 * Allocate the payload of a packet and initialize its fields to default values.
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 *
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 * @param pkt packet
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 * @param size wanted payload size
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 * @return 0 if OK. AVERROR_xxx otherwise.
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 */
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int av_new_packet(AVPacket *pkt, int size);
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/**
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 * Allocate and read the payload of a packet and initialize its fields to default values.
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 *
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 * @param pkt packet
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 * @param size wanted payload size
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 * @return >0 (read size) if OK. AVERROR_xxx otherwise.
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 */
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int av_get_packet(ByteIOContext *s, AVPacket *pkt, int size);
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/**
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 * @warning This is a hack - the packet memory allocation stuff is broken. The
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 * packet is allocated if it was not really allocated
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 */
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int av_dup_packet(AVPacket *pkt);
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/**
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 * Free a packet
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 *
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 * @param pkt packet to free
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 */
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static inline void av_free_packet(AVPacket *pkt)
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{
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    if (pkt && pkt->destruct) {
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        pkt->destruct(pkt);
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    }
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}
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/*************************************************/
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/* fractional numbers for exact pts handling */
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/**
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 * the exact value of the fractional number is: 'val + num / den'.
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 * num is assumed to be such as 0 <= num < den
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 * @deprecated Use AVRational instead
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*/
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typedef struct AVFrac {
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    int64_t val, num, den;
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} AVFrac attribute_deprecated;
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/*************************************************/
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/* input/output formats */
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struct AVCodecTag;
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struct AVFormatContext;
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/** this structure contains the data a format has to probe a file */
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typedef struct AVProbeData {
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    const char *filename;
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    unsigned char *buf;
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    int buf_size;
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} AVProbeData;
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#define AVPROBE_SCORE_MAX 100               ///< max score, half of that is used for file extension based detection
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#define AVPROBE_PADDING_SIZE 32             ///< extra allocated bytes at the end of the probe buffer
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typedef struct AVFormatParameters {
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    AVRational time_base;
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    int sample_rate;
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    int channels;
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    int width;
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    int height;
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    enum PixelFormat pix_fmt;
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    int channel; /**< used to select dv channel */
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    const char *standard; /**< tv standard, NTSC, PAL, SECAM */
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    int mpeg2ts_raw:1;  /**< force raw MPEG2 transport stream output, if possible */
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    int mpeg2ts_compute_pcr:1; /**< compute exact PCR for each transport
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                                  stream packet (only meaningful if
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                                  mpeg2ts_raw is TRUE) */
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    int initial_pause:1;       /**< do not begin to play the stream
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                                  immediately (RTSP only) */
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    int prealloced_context:1;
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#if LIBAVFORMAT_VERSION_INT < (53<<16)
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    enum CodecID video_codec_id;
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    enum CodecID audio_codec_id;
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#endif
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} AVFormatParameters;
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//! demuxer will use url_fopen, no opened file should be provided by the caller
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#define AVFMT_NOFILE        0x0001
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#define AVFMT_NEEDNUMBER    0x0002 /**< needs '%d' in filename */
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#define AVFMT_SHOW_IDS      0x0008 /**< show format stream IDs numbers */
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#define AVFMT_RAWPICTURE    0x0020 /**< format wants AVPicture structure for
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                                      raw picture data */
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#define AVFMT_GLOBALHEADER  0x0040 /**< format wants global header */
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#define AVFMT_NOTIMESTAMPS  0x0080 /**< format does not need / have any timestamps */
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#define AVFMT_GENERIC_INDEX 0x0100 /**< use generic index building code */
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typedef struct AVOutputFormat {
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    const char *name;
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    const char *long_name;
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    const char *mime_type;
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    const char *extensions; /**< comma separated filename extensions */
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    /** size of private data so that it can be allocated in the wrapper */
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    int priv_data_size;
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    /* output support */
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    enum CodecID audio_codec; /**< default audio codec */
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    enum CodecID video_codec; /**< default video codec */
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    int (*write_header)(struct AVFormatContext *);
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    int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
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    int (*write_trailer)(struct AVFormatContext *);
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    /** can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER */
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    int flags;
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    /** currently only used to set pixel format if not YUV420P */
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    int (*set_parameters)(struct AVFormatContext *, AVFormatParameters *);
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    int (*interleave_packet)(struct AVFormatContext *, AVPacket *out, AVPacket *in, int flush);
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    /**
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     * list of supported codec_id-codec_tag pairs, ordered by "better choice first"
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     * the arrays are all CODEC_ID_NONE terminated
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     */
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    const struct AVCodecTag **codec_tag;
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    enum CodecID subtitle_codec; /**< default subtitle codec */
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    /* private fields */
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    struct AVOutputFormat *next;
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} AVOutputFormat;
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typedef struct AVInputFormat {
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    const char *name;
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    const char *long_name;
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    /** size of private data so that it can be allocated in the wrapper */
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    int priv_data_size;
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    /**
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     * Tell if a given file has a chance of being parsed by this format.
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     * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
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     * big so you do not have to check for that unless you need more.
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     */
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    int (*read_probe)(AVProbeData *);
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    /** read the format header and initialize the AVFormatContext
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       structure. Return 0 if OK. 'ap' if non NULL contains
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       additional paramters. Only used in raw format right
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       now. 'av_new_stream' should be called to create new streams.  */
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    int (*read_header)(struct AVFormatContext *,
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                       AVFormatParameters *ap);
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    /** read one packet and put it in 'pkt'. pts and flags are also
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       set. 'av_new_stream' can be called only if the flag
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       AVFMTCTX_NOHEADER is used. */
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    int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
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    /** close the stream. The AVFormatContext and AVStreams are not
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       freed by this function */
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    int (*read_close)(struct AVFormatContext *);
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    /**
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     * seek to a given timestamp relative to the frames in
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     * stream component stream_index
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     * @param stream_index must not be -1
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     * @param flags selects which direction should be preferred if no exact
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     *              match is available
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     * @return >= 0 on success (but not necessarily the new offset)
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     */
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    int (*read_seek)(struct AVFormatContext *,
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                     int stream_index, int64_t timestamp, int flags);
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    /**
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     * gets the next timestamp in stream[stream_index].time_base units.
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     * @return the timestamp or AV_NOPTS_VALUE if an error occured
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     */
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    int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
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                              int64_t *pos, int64_t pos_limit);
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    /** can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER */
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    int flags;
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    /** if extensions are defined, then no probe is done. You should
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       usually not use extension format guessing because it is not
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       reliable enough */
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    const char *extensions;
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    /** general purpose read only value that the format can use */
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    int value;
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    /** start/resume playing - only meaningful if using a network based format
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       (RTSP) */
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    int (*read_play)(struct AVFormatContext *);
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    /** pause playing - only meaningful if using a network based format
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       (RTSP) */
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    int (*read_pause)(struct AVFormatContext *);
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    const struct AVCodecTag **codec_tag;
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    /* private fields */
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    struct AVInputFormat *next;
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} AVInputFormat;
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enum AVStreamParseType {
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    AVSTREAM_PARSE_NONE,
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    AVSTREAM_PARSE_FULL,       /**< full parsing and repack */
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    AVSTREAM_PARSE_HEADERS,    /**< only parse headers, don't repack */
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    AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on packet boundary */
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};
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typedef struct AVIndexEntry {
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    int64_t pos;
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    int64_t timestamp;
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#define AVINDEX_KEYFRAME 0x0001
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    int flags:2;
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    int size:30; //Yeah, trying to keep the size of this small to reduce memory requirements (it is 24 vs 32 byte due to possible 8byte align).
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    int min_distance;         /**< min distance between this and the previous keyframe, used to avoid unneeded searching */
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} AVIndexEntry;
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/**
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 * Stream structure.
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 * New fields can be added to the end with minor version bumps.
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 * Removal, reordering and changes to existing fields require a major
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 * version bump.
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 * sizeof(AVStream) must not be used outside libav*.
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 */
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typedef struct AVStream {
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    int index;    /**< stream index in AVFormatContext */
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    int id;       /**< format specific stream id */
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    AVCodecContext *codec; /**< codec context */
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    /**
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     * Real base frame rate of the stream.
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     * This is the lowest frame rate with which all timestamps can be
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     * represented accurately (it is the least common multiple of all
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     * frame rates in the stream), Note, this value is just a guess!
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     * For example if the timebase is 1/90000 and all frames have either
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     * approximately 3600 or 1800 timer ticks then r_frame_rate will be 50/1.
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     */
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    AVRational r_frame_rate;
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    void *priv_data;
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    /* internal data used in av_find_stream_info() */
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    int64_t first_dts;
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    /** encoding: PTS generation when outputing stream */
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    struct AVFrac pts;
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    /**
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     * This is the fundamental unit of time (in seconds) in terms
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     * of which frame timestamps are represented. For fixed-fps content,
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     * timebase should be 1/frame rate and timestamp increments should be
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     * identically 1.
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     */
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    AVRational time_base;
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    int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
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    /* ffmpeg.c private use */
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    int stream_copy; /**< if set, just copy stream */
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    enum AVDiscard discard; ///< selects which packets can be discarded at will and do not need to be demuxed
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    //FIXME move stuff to a flags field?
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    /** quality, as it has been removed from AVCodecContext and put in AVVideoFrame
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     * MN: dunno if that is the right place for it */
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    float quality;
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    /**
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     * Decoding: pts of the first frame of the stream, in stream time base.
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     * Only set this if you are absolutely 100% sure that the value you set
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     * it to really is the pts of the first frame.
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     * This may be undefined (AV_NOPTS_VALUE).
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     * @note The ASF header does NOT contain a correct start_time the ASF
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     * demuxer must NOT set this.
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     */
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    int64_t start_time;
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    /**
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     * Decoding: duration of the stream, in stream time base.
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     * If a source file does not specify a duration, but does specify
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     * a bitrate, this value will be estimates from bit rate and file size.
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     */
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    int64_t duration;
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    char language[4]; /** ISO 639 3-letter language code (empty string if undefined) */
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    /* av_read_frame() support */
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    enum AVStreamParseType need_parsing;
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    struct AVCodecParserContext *parser;
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    int64_t cur_dts;
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    int last_IP_duration;
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    int64_t last_IP_pts;
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    /* av_seek_frame() support */
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    AVIndexEntry *index_entries; /**< only used if the format does not
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                                    support seeking natively */
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    int nb_index_entries;
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    unsigned int index_entries_allocated_size;
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    int64_t nb_frames;                 ///< number of frames in this stream if known or 0
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#define MAX_REORDER_DELAY 4
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    int64_t pts_buffer[MAX_REORDER_DELAY+1];
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} AVStream;
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#define AV_PROGRAM_RUNNING 1
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/**
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 * New fields can be added to the end with minor version bumps.
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 * Removal, reordering and changes to existing fields require a major
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 * version bump.
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 * sizeof(AVProgram) must not be used outside libav*.
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 */
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typedef struct AVProgram {
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    int            id;
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    char           *provider_name; ///< Network name for DVB streams
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    char           *name;          ///< Service name for DVB streams
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    int            flags;
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    enum AVDiscard discard;        ///< selects which program to discard and which to feed to the caller
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    unsigned int   *stream_index;
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    unsigned int   nb_stream_indexes;
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} AVProgram;
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#define AVFMTCTX_NOHEADER      0x0001 /**< signal that no header is present
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                                         (streams are added dynamically) */
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#define MAX_STREAMS 20
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/**
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 * format I/O context.
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 * New fields can be added to the end with minor version bumps.
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 * Removal, reordering and changes to existing fields require a major
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 * version bump.
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 * sizeof(AVFormatContext) must not be used outside libav*.
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 */
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typedef struct AVFormatContext {
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    const AVClass *av_class; /**< set by av_alloc_format_context */
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    /* can only be iformat or oformat, not both at the same time */
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    struct AVInputFormat *iformat;
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    struct AVOutputFormat *oformat;
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    void *priv_data;
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    ByteIOContext *pb;
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    unsigned int nb_streams;
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    AVStream *streams[MAX_STREAMS];
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    char filename[1024]; /**< input or output filename */
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    /* stream info */
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    int64_t timestamp;
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    char title[512];
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    char author[512];
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    char copyright[512];
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    char comment[512];
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    char album[512];
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    int year;  /**< ID3 year, 0 if none */
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    int track; /**< track number, 0 if none */
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    char genre[32]; /**< ID3 genre */
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    int ctx_flags; /**< format specific flags, see AVFMTCTX_xx */
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    /* private data for pts handling (do not modify directly) */
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    /** This buffer is only needed when packets were already buffered but
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       not decoded, for example to get the codec parameters in mpeg
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       streams */
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    struct AVPacketList *packet_buffer;
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    /** decoding: position of the first frame of the component, in
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       AV_TIME_BASE fractional seconds. NEVER set this value directly:
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       it is deduced from the AVStream values.  */
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    int64_t start_time;
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    /** decoding: duration of the stream, in AV_TIME_BASE fractional
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       seconds. NEVER set this value directly: it is deduced from the
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       AVStream values.  */
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    int64_t duration;
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    /** decoding: total file size. 0 if unknown */
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    int64_t file_size;
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    /** decoding: total stream bitrate in bit/s, 0 if not
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       available. Never set it directly if the file_size and the
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       duration are known as ffmpeg can compute it automatically. */
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    int bit_rate;
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    /* av_read_frame() support */
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    AVStream *cur_st;
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    const uint8_t *cur_ptr;
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    int cur_len;
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    AVPacket cur_pkt;
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    /* av_seek_frame() support */
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    int64_t data_offset; /** offset of the first packet */
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    int index_built;
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    int mux_rate;
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    int packet_size;
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    int preload;
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    int max_delay;
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#define AVFMT_NOOUTPUTLOOP -1
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#define AVFMT_INFINITEOUTPUTLOOP 0
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    /** number of times to loop output in formats that support it */
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    int loop_output;
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    int flags;
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#define AVFMT_FLAG_GENPTS       0x0001 ///< generate pts if missing even if it requires parsing future frames
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#define AVFMT_FLAG_IGNIDX       0x0002 ///< ignore index
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#define AVFMT_FLAG_NONBLOCK     0x0004 ///< do not block when reading packets from input
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    int loop_input;
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    /** decoding: size of data to probe; encoding unused */
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    unsigned int probesize;
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    /**
455
     * maximum duration in AV_TIME_BASE units over which the input should be analyzed in av_find_stream_info()
456
     */
457
    int max_analyze_duration;
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459
    const uint8_t *key;
460
    int keylen;
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462
    unsigned int nb_programs;
463
    AVProgram **programs;
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    /**
466
     * Forced video codec_id.
467
     * demuxing: set by user
468
     */
469
    enum CodecID video_codec_id;
470
    /**
471
     * Forced audio codec_id.
472
     * demuxing: set by user
473
     */
474
    enum CodecID audio_codec_id;
475
    /**
476
     * Forced subtitle codec_id.
477
     * demuxing: set by user
478
     */
479
    enum CodecID subtitle_codec_id;
480

    
481
    /**
482
     * Maximum amount of memory in bytes to use per stream for the index.
483
     * If the needed index exceeds this size entries will be discarded as
484
     * needed to maintain a smaller size. This can lead to slower or less
485
     * accurate seeking (depends on demuxer).
486
     * Demuxers for which a full in memory index is mandatory will ignore
487
     * this.
488
     * muxing  : unused
489
     * demuxing: set by user
490
     */
491
    unsigned int max_index_size;
492
} AVFormatContext;
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typedef struct AVPacketList {
495
    AVPacket pkt;
496
    struct AVPacketList *next;
497
} AVPacketList;
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#if LIBAVFORMAT_VERSION_INT < (53<<16)
500
extern AVInputFormat *first_iformat;
501
extern AVOutputFormat *first_oformat;
502
#endif
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AVInputFormat  *av_iformat_next(AVInputFormat  *f);
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AVOutputFormat *av_oformat_next(AVOutputFormat *f);
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enum CodecID av_guess_image2_codec(const char *filename);
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/* XXX: use automatic init with either ELF sections or C file parser */
510
/* modules */
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/* utils.c */
513
void av_register_input_format(AVInputFormat *format);
514
void av_register_output_format(AVOutputFormat *format);
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AVOutputFormat *guess_stream_format(const char *short_name,
516
                                    const char *filename, const char *mime_type);
517
AVOutputFormat *guess_format(const char *short_name,
518
                             const char *filename, const char *mime_type);
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/**
521
 * Guesses the codec id based upon muxer and filename.
522
 */
523
enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
524
                            const char *filename, const char *mime_type, enum CodecType type);
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/**
527
 * Send a nice hexadecimal dump of a buffer to the specified file stream.
528
 *
529
 * @param f The file stream pointer where the dump should be sent to.
530
 * @param buf buffer
531
 * @param size buffer size
532
 *
533
 * @see av_hex_dump_log, av_pkt_dump, av_pkt_dump_log
534
 */
535
void av_hex_dump(FILE *f, uint8_t *buf, int size);
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537
/**
538
 * Send a nice hexadecimal dump of a buffer to the log.
539
 *
540
 * @param avcl A pointer to an arbitrary struct of which the first field is a
541
 * pointer to an AVClass struct.
542
 * @param level The importance level of the message, lower values signifying
543
 * higher importance.
544
 * @param buf buffer
545
 * @param size buffer size
546
 *
547
 * @see av_hex_dump, av_pkt_dump, av_pkt_dump_log
548
 */
549
void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size);
550

    
551
/**
552
 * Send a nice dump of a packet to the specified file stream.
553
 *
554
 * @param f The file stream pointer where the dump should be sent to.
555
 * @param pkt packet to dump
556
 * @param dump_payload true if the payload must be displayed too
557
 */
558
void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
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560
/**
561
 * Send a nice dump of a packet to the log.
562
 *
563
 * @param avcl A pointer to an arbitrary struct of which the first field is a
564
 * pointer to an AVClass struct.
565
 * @param level The importance level of the message, lower values signifying
566
 * higher importance.
567
 * @param pkt packet to dump
568
 * @param dump_payload true if the payload must be displayed too
569
 */
570
void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt, int dump_payload);
571

    
572
void av_register_all(void);
573

    
574
/** codec tag <-> codec id */
575
enum CodecID av_codec_get_id(const struct AVCodecTag **tags, unsigned int tag);
576
unsigned int av_codec_get_tag(const struct AVCodecTag **tags, enum CodecID id);
577

    
578
/* media file input */
579

    
580
/**
581
 * finds AVInputFormat based on input format's short name.
582
 */
583
AVInputFormat *av_find_input_format(const char *short_name);
584

    
585
/**
586
 * Guess file format.
587
 *
588
 * @param is_opened whether the file is already opened, determines whether
589
 *                  demuxers with or without AVFMT_NOFILE are probed
590
 */
591
AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
592

    
593
/**
594
 * Allocates all the structures needed to read an input stream.
595
 *        This does not open the needed codecs for decoding the stream[s].
596
 */
597
int av_open_input_stream(AVFormatContext **ic_ptr,
598
                         ByteIOContext *pb, const char *filename,
599
                         AVInputFormat *fmt, AVFormatParameters *ap);
600

    
601
/**
602
 * Open a media file as input. The codecs are not opened. Only the file
603
 * header (if present) is read.
604
 *
605
 * @param ic_ptr the opened media file handle is put here
606
 * @param filename filename to open.
607
 * @param fmt if non NULL, force the file format to use
608
 * @param buf_size optional buffer size (zero if default is OK)
609
 * @param ap additional parameters needed when opening the file (NULL if default)
610
 * @return 0 if OK. AVERROR_xxx otherwise.
611
 */
612
int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
613
                       AVInputFormat *fmt,
614
                       int buf_size,
615
                       AVFormatParameters *ap);
616
/**
617
 * Allocate an AVFormatContext.
618
 * Can be freed with av_free() but do not forget to free everything you
619
 * explicitly allocated as well!
620
 */
621
AVFormatContext *av_alloc_format_context(void);
622

    
623
/**
624
 * Read packets of a media file to get stream information. This
625
 * is useful for file formats with no headers such as MPEG. This
626
 * function also computes the real frame rate in case of mpeg2 repeat
627
 * frame mode.
628
 * The logical file position is not changed by this function;
629
 * examined packets may be buffered for later processing.
630
 *
631
 * @param ic media file handle
632
 * @return >=0 if OK. AVERROR_xxx if error.
633
 * @todo Let user decide somehow what information is needed so we do not waste time getting stuff the user does not need.
634
 */
635
int av_find_stream_info(AVFormatContext *ic);
636

    
637
/**
638
 * Read a transport packet from a media file.
639
 *
640
 * This function is obsolete and should never be used.
641
 * Use av_read_frame() instead.
642
 *
643
 * @param s media file handle
644
 * @param pkt is filled
645
 * @return 0 if OK. AVERROR_xxx if error.
646
 */
647
int av_read_packet(AVFormatContext *s, AVPacket *pkt);
648

    
649
/**
650
 * Return the next frame of a stream.
651
 *
652
 * The returned packet is valid
653
 * until the next av_read_frame() or until av_close_input_file() and
654
 * must be freed with av_free_packet. For video, the packet contains
655
 * exactly one frame. For audio, it contains an integer number of
656
 * frames if each frame has a known fixed size (e.g. PCM or ADPCM
657
 * data). If the audio frames have a variable size (e.g. MPEG audio),
658
 * then it contains one frame.
659
 *
660
 * pkt->pts, pkt->dts and pkt->duration are always set to correct
661
 * values in AVStream.timebase units (and guessed if the format cannot
662
 * provided them). pkt->pts can be AV_NOPTS_VALUE if the video format
663
 * has B frames, so it is better to rely on pkt->dts if you do not
664
 * decompress the payload.
665
 *
666
 * @return 0 if OK, < 0 if error or end of file.
667
 */
668
int av_read_frame(AVFormatContext *s, AVPacket *pkt);
669

    
670
/**
671
 * Seek to the key frame at timestamp.
672
 * 'timestamp' in 'stream_index'.
673
 * @param stream_index If stream_index is (-1), a default
674
 * stream is selected, and timestamp is automatically converted
675
 * from AV_TIME_BASE units to the stream specific time_base.
676
 * @param timestamp timestamp in AVStream.time_base units
677
 *        or if there is no stream specified then in AV_TIME_BASE units
678
 * @param flags flags which select direction and seeking mode
679
 * @return >= 0 on success
680
 */
681
int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags);
682

    
683
/**
684
 * start playing a network based stream (e.g. RTSP stream) at the
685
 * current position
686
 */
687
int av_read_play(AVFormatContext *s);
688

    
689
/**
690
 * Pause a network based stream (e.g. RTSP stream).
691
 *
692
 * Use av_read_play() to resume it.
693
 */
694
int av_read_pause(AVFormatContext *s);
695

    
696
/**
697
 * Free a AVFormatContext allocated by av_open_input_stream.
698
 * @param s context to free
699
 */
700
void av_close_input_stream(AVFormatContext *s);
701

    
702
/**
703
 * Close a media file (but not its codecs).
704
 *
705
 * @param s media file handle
706
 */
707
void av_close_input_file(AVFormatContext *s);
708

    
709
/**
710
 * Add a new stream to a media file.
711
 *
712
 * Can only be called in the read_header() function. If the flag
713
 * AVFMTCTX_NOHEADER is in the format context, then new streams
714
 * can be added in read_packet too.
715
 *
716
 * @param s media file handle
717
 * @param id file format dependent stream id
718
 */
719
AVStream *av_new_stream(AVFormatContext *s, int id);
720
AVProgram *av_new_program(AVFormatContext *s, int id);
721

    
722
/**
723
 * Set the pts for a given stream.
724
 *
725
 * @param s stream
726
 * @param pts_wrap_bits number of bits effectively used by the pts
727
 *        (used for wrap control, 33 is the value for MPEG)
728
 * @param pts_num numerator to convert to seconds (MPEG: 1)
729
 * @param pts_den denominator to convert to seconds (MPEG: 90000)
730
 */
731
void av_set_pts_info(AVStream *s, int pts_wrap_bits,
732
                     int pts_num, int pts_den);
733

    
734
#define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
735
#define AVSEEK_FLAG_BYTE     2 ///< seeking based on position in bytes
736
#define AVSEEK_FLAG_ANY      4 ///< seek to any frame, even non keyframes
737

    
738
int av_find_default_stream_index(AVFormatContext *s);
739

    
740
/**
741
 * Gets the index for a specific timestamp.
742
 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond to
743
 *                 the timestamp which is <= the requested one, if backward is 0
744
 *                 then it will be >=
745
 *              if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
746
 * @return < 0 if no such timestamp could be found
747
 */
748
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
749

    
750
/**
751
 * Ensures the index uses less memory than the maximum specified in
752
 * AVFormatContext.max_index_size, by discarding entries if it grows
753
 * too large.
754
 * This function is not part of the public API and should only be called
755
 * by demuxers.
756
 */
757
void ff_reduce_index(AVFormatContext *s, int stream_index);
758

    
759
/**
760
 * Add a index entry into a sorted list updateing if it is already there.
761
 *
762
 * @param timestamp timestamp in the timebase of the given stream
763
 */
764
int av_add_index_entry(AVStream *st,
765
                       int64_t pos, int64_t timestamp, int size, int distance, int flags);
766

    
767
/**
768
 * Does a binary search using av_index_search_timestamp() and AVCodec.read_timestamp().
769
 * This is not supposed to be called directly by a user application, but by demuxers.
770
 * @param target_ts target timestamp in the time base of the given stream
771
 * @param stream_index stream number
772
 */
773
int av_seek_frame_binary(AVFormatContext *s, int stream_index, int64_t target_ts, int flags);
774

    
775
/**
776
 * Updates cur_dts of all streams based on given timestamp and AVStream.
777
 *
778
 * Stream ref_st unchanged, others set cur_dts in their native timebase
779
 * only needed for timestamp wrapping or if (dts not set and pts!=dts).
780
 * @param timestamp new dts expressed in time_base of param ref_st
781
 * @param ref_st reference stream giving time_base of param timestamp
782
 */
783
void av_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
784

    
785
/**
786
 * Does a binary search using read_timestamp().
787
 * This is not supposed to be called directly by a user application, but by demuxers.
788
 * @param target_ts target timestamp in the time base of the given stream
789
 * @param stream_index stream number
790
 */
791
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 ));
792

    
793
/** media file output */
794
int av_set_parameters(AVFormatContext *s, AVFormatParameters *ap);
795

    
796
/**
797
 * Allocate the stream private data and write the stream header to an
798
 * output media file.
799
 *
800
 * @param s media file handle
801
 * @return 0 if OK. AVERROR_xxx if error.
802
 */
803
int av_write_header(AVFormatContext *s);
804

    
805
/**
806
 * Write a packet to an output media file.
807
 *
808
 * The packet shall contain one audio or video frame.
809
 * The packet must be correctly interleaved according to the container specification,
810
 * if not then av_interleaved_write_frame must be used
811
 *
812
 * @param s media file handle
813
 * @param pkt the packet, which contains the stream_index, buf/buf_size, dts/pts, ...
814
 * @return < 0 if error, = 0 if OK, 1 if end of stream wanted.
815
 */
816
int av_write_frame(AVFormatContext *s, AVPacket *pkt);
817

    
818
/**
819
 * Writes a packet to an output media file ensuring correct interleaving.
820
 *
821
 * The packet must contain one audio or video frame.
822
 * If the packets are already correctly interleaved the application should
823
 * call av_write_frame() instead as it is slightly faster. It is also important
824
 * to keep in mind that completely non-interleaved input will need huge amounts
825
 * of memory to interleave with this, so it is preferable to interleave at the
826
 * demuxer level.
827
 *
828
 * @param s media file handle
829
 * @param pkt the packet, which contains the stream_index, buf/buf_size, dts/pts, ...
830
 * @return < 0 if error, = 0 if OK, 1 if end of stream wanted.
831
 */
832
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
833

    
834
/**
835
 * Interleave a packet per DTS in an output media file.
836
 *
837
 * Packets with pkt->destruct == av_destruct_packet will be freed inside this function,
838
 * so they cannot be used after it, note calling av_free_packet() on them is still safe.
839
 *
840
 * @param s media file handle
841
 * @param out the interleaved packet will be output here
842
 * @param in the input packet
843
 * @param flush 1 if no further packets are available as input and all
844
 *              remaining packets should be output
845
 * @return 1 if a packet was output, 0 if no packet could be output,
846
 *         < 0 if an error occured
847
 */
848
int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out, AVPacket *pkt, int flush);
849

    
850
/**
851
 * @brief Write the stream trailer to an output media file and
852
 *        free the file private data.
853
 *
854
 * @param s media file handle
855
 * @return 0 if OK. AVERROR_xxx if error.
856
 */
857
int av_write_trailer(AVFormatContext *s);
858

    
859
void dump_format(AVFormatContext *ic,
860
                 int index,
861
                 const char *url,
862
                 int is_output);
863

    
864
/**
865
 * parses width and height out of string str.
866
 * @deprecated Use av_parse_video_frame_size instead.
867
 */
868
attribute_deprecated int parse_image_size(int *width_ptr, int *height_ptr, const char *str);
869

    
870
/**
871
 * Converts frame rate from string to a fraction.
872
 * @deprecated Use av_parse_video_frame_rate instead.
873
 */
874
attribute_deprecated int parse_frame_rate(int *frame_rate, int *frame_rate_base, const char *arg);
875

    
876
/**
877
 * Parses \p datestr and returns a corresponding number of microseconds.
878
 * @param datestr String representing a date or a duration.
879
 * - If a date the syntax is:
880
 * @code
881
 *  [{YYYY-MM-DD|YYYYMMDD}]{T| }{HH[:MM[:SS[.m...]]][Z]|HH[MM[SS[.m...]]][Z]}
882
 * @endcode
883
 * Time is localtime unless Z is appended, in which case it is
884
 * interpreted as UTC.
885
 * If the year-month-day part isn't specified it takes the current
886
 * year-month-day.
887
 * Returns the number of microseconds since 1st of January, 1970 up to
888
 * the time of the parsed date or INT64_MIN if \p datestr cannot be
889
 * successfully parsed.
890
 * - If a duration the syntax is:
891
 * @code
892
 *  [-]HH[:MM[:SS[.m...]]]
893
 *  [-]S+[.m...]
894
 * @endcode
895
 * Returns the number of microseconds contained in a time interval
896
 * with the specified duration or INT64_MIN if \p datestr cannot be
897
 * successfully parsed.
898
 * @param duration Flag which tells how to interpret \p datestr, if
899
 * not zero \p datestr is interpreted as a duration, otherwise as a
900
 * date.
901
 */
902
int64_t parse_date(const char *datestr, int duration);
903

    
904
int64_t av_gettime(void);
905

    
906
/* ffm specific for ffserver */
907
#define FFM_PACKET_SIZE 4096
908
offset_t ffm_read_write_index(int fd);
909
void ffm_write_write_index(int fd, offset_t pos);
910
void ffm_set_write_index(AVFormatContext *s, offset_t pos, offset_t file_size);
911

    
912
/**
913
 * Attempts to find a specific tag in a URL.
914
 *
915
 * syntax: '?tag1=val1&tag2=val2...'. Little URL decoding is done.
916
 * Return 1 if found.
917
 */
918
int find_info_tag(char *arg, int arg_size, const char *tag1, const char *info);
919

    
920
/**
921
 * Returns in 'buf' the path with '%d' replaced by number.
922

923
 * Also handles the '%0nd' format where 'n' is the total number
924
 * of digits and '%%'.
925
 *
926
 * @param buf destination buffer
927
 * @param buf_size destination buffer size
928
 * @param path numbered sequence string
929
 * @param number frame number
930
 * @return 0 if OK, -1 if format error.
931
 */
932
int av_get_frame_filename(char *buf, int buf_size,
933
                          const char *path, int number);
934

    
935
/**
936
 * Check whether filename actually is a numbered sequence generator.
937
 *
938
 * @param filename possible numbered sequence string
939
 * @return 1 if a valid numbered sequence string, 0 otherwise.
940
 */
941
int av_filename_number_test(const char *filename);
942

    
943
/**
944
 * Generate an SDP for an RTP session.
945
 *
946
 * @param ac array of AVFormatContexts describing the RTP streams. If the
947
 *           array is composed by only one context, such context can contain
948
 *           multiple AVStreams (one AVStream per RTP stream). Otherwise,
949
 *           all the contexts in the array (an AVCodecContext per RTP stream)
950
 *           must contain only one AVStream
951
 * @param n_files number of AVCodecContexts contained in ac
952
 * @param buff buffer where the SDP will be stored (must be allocated by
953
 *             the caller
954
 * @param size the size of the buffer
955
 * @return 0 if OK. AVERROR_xxx if error.
956
 */
957
int avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size);
958

    
959
#ifdef HAVE_AV_CONFIG_H
960

    
961
void __dynarray_add(unsigned long **tab_ptr, int *nb_ptr, unsigned long elem);
962

    
963
#ifdef __GNUC__
964
#define dynarray_add(tab, nb_ptr, elem)\
965
do {\
966
    typeof(tab) _tab = (tab);\
967
    typeof(elem) _elem = (elem);\
968
    (void)sizeof(**_tab == _elem); /* check that types are compatible */\
969
    __dynarray_add((unsigned long **)_tab, nb_ptr, (unsigned long)_elem);\
970
} while(0)
971
#else
972
#define dynarray_add(tab, nb_ptr, elem)\
973
do {\
974
    __dynarray_add((unsigned long **)(tab), nb_ptr, (unsigned long)(elem));\
975
} while(0)
976
#endif
977

    
978
time_t mktimegm(struct tm *tm);
979
struct tm *brktimegm(time_t secs, struct tm *tm);
980
const char *small_strptime(const char *p, const char *fmt,
981
                           struct tm *dt);
982

    
983
struct in_addr;
984
int resolve_host(struct in_addr *sin_addr, const char *hostname);
985

    
986
void url_split(char *proto, int proto_size,
987
               char *authorization, int authorization_size,
988
               char *hostname, int hostname_size,
989
               int *port_ptr,
990
               char *path, int path_size,
991
               const char *url);
992

    
993
int match_ext(const char *filename, const char *extensions);
994

    
995
#endif /* HAVE_AV_CONFIG_H */
996

    
997
#endif /* FFMPEG_AVFORMAT_H */