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                                                                              (*
 * copyright (c) 2001 Fabrice Bellard
 *
 * This library 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 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
                                                                              *)

(* This is a part of Pascal porting of ffmpeg.  Originally by Victor Zinetz for Delphi and Free Pascal on Windows.
For Mac OS X, some modifications were made by The Creative CAT, denoted as CAT
in the source codes *)

unit avformat;

{$IFDEF FPC}
  {$IFNDEF win32}
  {$LINKLIB libavutil}
  {$LINKLIB libavformat}
  {$ENDIF}

  {$MODE DELPHI } (* CAT *)
  {$PACKENUM 4}    (* every enum type variables uses 4 bytes, CAT *)
  {$PACKRECORDS C}    (* GCC compatible, Record Packing, CAT *)
{$ENDIF}

interface

uses
  avcodec,
  avio,
  rational,
  avutil; (* CAT *)

const


{$IFDEF win32}
  av__format = 'avformat-50.dll';
{$ELSE}
  av__format = 'libavformat.so';   // .0d
  //av__format = 'libavformat.51'; (* CAT *)
{$ENDIF}

  LIBAVUTIL_VERSION_INT   =  ((51 shl 16) + (12 shl 8) + 1);
  LIBAVUTIL_VERSION       = '51.12.1';
  LIBAVUTIL_BUILD         = LIBAVUTIL_VERSION_INT;

  MAXINT64 = $7fffffffffffffff;
  MININT64 = $8000000000000000;

  PKT_FLAG_KEY = $0001;

(*************************************************)
(* input/output formats *)

  AVPROBE_SCORE_MAX   = 100;   ///< max score, half of that is used for file extension based detection
  AVPROBE_PADDING_SIZE = 32;   ///< extra allocated bytes at the end of the probe buffer

//! demuxer will use url_fopen, no opened file should be provided by the caller
  AVFMT_NOFILE = $0001;
  AVFMT_NEEDNUMBER = $0002; (**< needs '%d' in filename *)
  AVFMT_SHOW_IDS = $0008; (**< show format stream IDs numbers *)
  AVFMT_RAWPICTURE = $0020; (**< format wants AVPicture structure for
                                      raw picture data *)
  AVFMT_GLOBALHEADER = $0040; (**< format wants global header *)
  AVFMT_NOTIMESTAMPS = $0080; (**< format does not need / have any timestamps *)
  AVFMT_GENERIC_INDEX = $0100; (**< use generic index building code *)

  AVINDEX_KEYFRAME = $0001;

  MAX_REORDER_DELAY = 4;

  AVFMTCTX_NOHEADER = $0001; (**< signal that no header is present
                                         (streams are added dynamically) *)
  MAX_STREAMS = 20;
  AVFMT_NOOUTPUTLOOP = -1;
  AVFMT_INFINITEOUTPUTLOOP = 0;
  AVFMT_FLAG_GENPTS = $0001; ///< generate pts if missing even if it requires parsing future frames
  AVFMT_FLAG_IGNIDX = $0002; ///< ignore index
  AVFMT_FLAG_NONBLOCK = $0004; ///< do not block when reading packets from input

type
  HFILE = THandle; /// (* CAT *)
  int = integer;

  PAVPacket = ^TAVPacket;
  PAVImageFormat = ^TAVImageFormat;
  PAVFormatContext = ^TAVFormatContext;
  PAVFormatParameters = ^TAVFormatParameters;
  PAVOutputFormat = ^TAVOutputFormat;
  PAVProbeData = ^TAVProbeData;
  PAVInputFormat = ^TAVInputFormat;
  PAVIndexEntry = ^TAVIndexEntry;
  PAVStream = ^TAVStream;
  PAVPacketList = ^TAVPacketList;
  PAVImageInfo = ^TAVImageInfo;

  TAVPacket = record {56}
    pts: int64;                            ///< presentation time stamp in time_base units
    dts: int64;                            ///< decompression time stamp in time_base units
    data: PByte;
    size: integer;
    stream_index: integer;
    flags: integer;
    duration: integer;                         ///< presentation duration in time_base units (0 if not available)
    destruct: procedure (p: PAVPacket);  (* This cannot be var : TAVPacket. 
										because TAVPacket is not completely defined yet *)
    priv: pointer;
    pos: int64                            ///< byte position in stream, -1 if unknown
  end;

(*************************************************)
(* fractional numbers for exact pts handling *)

(* the exact value of the fractional number is: 'val + num / den'. num
   is assumed to be such as 0 <= num < den *)
  PAVFrac = ^TAVFrac;
  TAVFrac = record
    val, num, den: int64;
  end;

(* this structure contains the data a format has to probe a file *)
  TAVProbeData = record {12}
    filename: pchar;
    buf: pchar;
    buf_size: integer;
  end;

  TAVFormatParameters = record {56}
    time_base: TAVRational; (* 8 bytes *)
    sample_rate: integer;
    channels: integer;
    width: integer;
    height: integer;
    pix_fmt: TAVPixelFormat;
{    image_format: PAVImageFormat; (* 4 bytes *)}  (* CAT#3 *)
    channel: integer; (* used to select dv channel *)
    device: pchar; (* video, audio or DV device, if LIBAVFORMAT_VERSION_INT < (52<<16) *)
    standard: pchar; (* tv standard, NTSC, PAL, SECAM *)
//    int mpeg2ts_raw:1;  (* force raw MPEG2 transport stream output, if possible *)
//    int mpeg2ts_compute_pcr:1; (* compute exact PCR for each transport
//                                  stream packet (only meaningful if
//                                  mpeg2ts_raw is TRUE *)
//    int initial_pause:1;       (* do not begin to play the stream
//                                  immediately (RTSP only) *)
//    int prealloced_context:1;
    dummy: byte;
    video_codec_id: TCodecID;
    audio_codec_id: TCodecID;
  end;

  TAVOutputFormat = record {56}
    name: pchar;
    long_name: pchar;
    mime_type: pchar;
    extensions: pchar; (* comma separated extensions *)
    (* size of private data so that it can be allocated in the wrapper *)
    priv_data_size: integer;
    (* output support *)
    audio_codec: TCodecID; (* default audio codec *)
    video_codec: TCodecID; (* default video codec *)
    write_header: function (c: PAVFormatContext): integer; cdecl;
    write_packet: function (c: PAVFormatContext; var pkt: TAVPacket): integer; cdecl; (* CAT#2 *)
    write_trailer: function (c: PAVFormatContext): integer; cdecl;
    (* can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER *)
    flags: integer;
    (* currently only used to set pixel format if not YUV420P *)
    set_parameters: function (c: PAVFormatContext; f: PAVFormatParameters): integer; cdecl;
    interleave_packet: function (s: PAVFormatContext; _out: PAVPacket; _in: PAVPacket; flush: integer): integer; cdecl;

    (**
     * list of supported codec_id-codec_tag pairs, ordered by "better choice first"
     * the arrays are all CODEC_ID_NONE terminated
     *)
    //const struct AVCodecTag **codec_tag;

    (* private fields *)
    next: PAVOutputFormat;
  end;

  TAVInputFormat = record {60}
    name: pchar;
    long_name: pchar;
    (* size of private data so that it can be allocated in the wrapper *)
    priv_data_size: integer;
    (* tell if a given file has a chance of being parsing by this format *)
    read_probe: function (p: PAVProbeData): integer; cdecl;
    (* read the format header and initialize the AVFormatContext
       structure. Return 0 if OK. 'ap' if non NULL contains
       additionnal paramters. Only used in raw format right
       now. 'av_new_stream' should be called to create new streams.  *)
    read_header: function (c: PAVFormatContext; ap: PAVFormatParameters): integer; cdecl;
    (* 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. *)
    read_packet: function (c: PAVFormatContext; var pkt: TAVPacket): integer; cdecl;
    (* close the stream. The AVFormatContext and AVStreams are not
       freed by this function *)
    read_close: function (c: PAVFormatContext): integer; cdecl;
    (*** 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     *)
    read_seek: function (c: PAVFormatContext; stream_index: integer;
                  timestamp: int64; flags: integer): integer; cdecl;
    (*** gets the next timestamp in AV_TIME_BASE units.     *)
    read_timestamp: function (s: PAVFormatContext; stream_index: integer;
                              pos: pint64; pos_limit: int64): integer; cdecl;
    (* can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER *)
    flags: integer;
    (* if extensions are defined, then no probe is done. You should
       usually not use extension format guessing because it is not
       reliable enough *)
    extensions: pchar;
    (* general purpose read only value that the format can use *)
    value: integer;

    (* start/resume playing - only meaningful if using a network based format (RTSP) *)
    read_play: function (c: PAVFormatContext): integer; cdecl;

    (* pause playing - only meaningful if using a network based format  (RTSP) *)
    read_pause: function (c: PAVFormatContext): integer; cdecl;

    //const struct AVCodecTag **codec_tag;

    (* private fields *)
    next: PAVInputFormat;
  end;

  TAVStreamParseType = (
    AVSTREAM_PARSE_NONE,
    AVSTREAM_PARSE_FULL,       (**< full parsing and repack *)
    AVSTREAM_PARSE_HEADERS,    (**< only parse headers, don't repack *)
    AVSTREAM_PARSE_TIMESTAMPS  (**< full parsing and interpolation of timestamps for frames not starting on packet boundary *)
    );

  TAVIndexEntry = record {24}
    pos: int64;
    timestamp: int64;
(* the following 2 flags indicate that the next/prev keyframe is known, and scaning for it isnt needed *)
    flags: integer;
//    int flags:2;
//    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).
    min_distance: integer;         (* min distance between this and the previous keyframe, used to avoid unneeded searching *)
  end;

  TAVStream = record {168}
    index: integer;    (* stream index in AVFormatContext *) {4-4}
    id: integer;       (* format specific stream id *)       {4-8}
    codec: PAVCodecContext; (* codec context *)              {4-12}
    (*** real base frame rate of the stream.
     * for example if the timebase is 1/90000 and all frames have either
     * approximately 3600 or 1800 timer ticks then r_frame_rate will be 50/1     *)
    r_frame_rate: TAVRational;                               {4*2=8-20}
    priv_data: pointer;                                      {4-24}
    (* internal data used in av_find_stream_info() *)
    codec_info_duration: int64; (* #if LIBAVFORMAT_VERSION_INT < (52<<16) *)  {8-32}
    codec_info_nb_frames: integer; (* #if LIBAVFORMAT_VERSION_INT < (52<<16) *) {4-38}
    (* encoding: PTS generation when outputing stream *)
    pts: TAVFrac;                                            {8*3=24-62}

    (*** this is the fundamental unit of time (in seconds) in terms
     * of which frame timestamps are represented. for fixed-fps content,
     * timebase should be 1/framerate and timestamp increments should be
     * identically 1.     *)
    time_base: TAVRational;                                  {4*2=8-70}
    pts_wrap_bits: integer; (* number of bits in pts (used for wrapping control) *) {4-74}
    (* ffmpeg.c private use *)
    stream_copy: integer; (* if TRUE, just copy stream *)  {4-78}
    discard: TAVDiscard; ///< selects which packets can be discarded at will and dont need to be demuxed {4-82}
    //FIXME move stuff to a flags field?
    (* quality, as it has been removed from AVCodecContext and put in AVVideoFrame
     * MN:dunno if thats the right place, for it *)
    quality: single; {4-86}
    (* decoding: position of the first frame of the component, in AV_TIME_BASE fractional seconds. *)
    start_time: int64; {8-92}
    (* decoding: duration of the stream, in stream time base. *)
    duration: int64; {8-100}

    language: array [0..3] of char; (* ISO 639 3-letter language code (empty string if undefined) *)(* 101 th byte - 1 base *) {4-104}

    (* av_read_frame() support *)
    need_parsing: TAVStreamParseType;//CAT#3           ///< 1->full parsing needed, 2->only parse headers dont repack
    parser: PAVCodecParserContext;

    cur_dts: int64;
    last_IP_duration: integer;
    last_IP_pts: int64;
    (* av_seek_frame() support *)
    index_entries: PAVIndexEntry; (* only used if the format does not support seeking natively *)
    nb_index_entries: integer;
    index_entries_allocated_size: cardinal; (* CAT#3 *)

    nb_frames: int64;                 ///< number of frames in this stream if known or 0
    pts_buffer: array [0..MAX_REORDER_DELAY] of int64
  end;

(* format I/O context *)
  TAVFormatContext = record {3960}
    av_class: PAVClass; (* set by av_alloc_format_context *)
    (* can only be iformat or oformat, not both at the same time *)
    iformat: PAVInputFormat;
    oformat: PAVOutputFormat;
    priv_data: pointer;
    pb: TByteIOContext;
    nb_streams: cardinal;  (* CAT#3 *)
    streams: array [0..MAX_STREAMS - 1] of PAVStream;
    filename: array [0..1023] of char; (* input or output filename *)
    (* stream info *)
    timestamp: int64;
    title: array [0..511] of char;
    author: array [0..511] of char;
    copyright: array [0..511] of char;
    comment: array [0..511] of char;
    album: array [0..511] of char;
    year: integer;  (* ID3 year, 0 if none *)
    track: integer; (* track number, 0 if none *)
    genre: array [0..31] of char; (* ID3 genre *)

    ctx_flags: integer; (* 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 *)
    packet_buffer: PAVPacketList;

    (* 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.  *)
    start_time: int64;
    (* decoding: duration of the stream, in AV_TIME_BASE fractional
       seconds. NEVER set this value directly: it is deduced from the
       AVStream values.  *)
    duration: int64;
    (* decoding: total file size. 0 if unknown *)
    file_size: int64;
    (* 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. *)
    bit_rate: integer;

    (* av_read_frame() support *)
    cur_st: PAVStream;
    cur_ptr: pbyte;
    cur_len: integer;
    cur_pkt: TAVPacket;

    (* av_seek_frame() support *)
    data_offset: int64; (* offset of the first packet *)
    index_built: integer;

    mux_rate: integer;
    packet_size: integer;
    preload: integer;
    max_delay: integer;

    (* number of times to loop output in formats that support it *)
    loop_output: integer;

    flags: integer;
    loop_input: integer;
    (* decoding: size of data to probe; encoding unused *)
    probesize: cardinal;

    (**
     * maximum duration in AV_TIME_BASE units over which the input should be analyzed in av_find_stream_info()
     *)
    max_analyze_duration: integer;

    key: pbyte;
    keylen : integer
  end;

  TAVPacketList = record {64}
    pkt: TAVPacket;
    next: PAVPacketList;
  end;

(* still image support *)
  PAVInputImageContext = pointer; // attribute_deprecated;
//  PAVInputImageContext = pointer; //AVInputImageContext attribute_deprecated;

(* still image support *)
  TAVImageInfo = record {48}
    pix_fmt: TAVPixelFormat; (* requested pixel format *)
    width: integer; (* requested width *)
    height: integer; (* requested height *)
    interleaved: integer; (* image is interleaved (e.g. interleaved GIF) *)
    pict: TAVPicture; (* returned allocated image *)
  end;

  TAVImageFormat = record {32}
    name: pchar;
    extensions: pchar;
    (* tell if a given file has a chance of being parsing by this format *)
    img_probe: function (d: PAVProbeData): integer; cdecl;
    (* read a whole image. 'alloc_cb' is called when the image size is
       known so that the caller can allocate the image. If 'allo_cb'
       returns non zero, then the parsing is aborted. Return '0' if
       OK. *)
    img_read: function (b: PByteIOContext; alloc_cb: pointer; ptr: pointer): integer; cdecl;
    (* write the image *)
    supported_pixel_formats: integer; (* mask of supported formats for output *)
    img_write: function (b: PByteIOContext; i: PAVImageInfo): integer; cdecl;
    flags: integer;
    next: PAVImageFormat;
  end;

procedure av_destruct_packet_nofree (var pkt: TAVPacket); (* CAT#2 *)
  cdecl; external av__format;
procedure av_destruct_packet (var pkt: TAVPacket); (* CAT#2 *)
  cdecl; external av__format;

(* initialize optional fields of a packet *)
procedure av_init_packet (var pkt: TAVPacket);  (* CAT#2 *)

function av_new_packet(var pkt: TAVPacket; size: integer): integer; (* CAT#2 *)
  cdecl; external av__format;

function av_get_packet (s: PByteIOContext; var pkt: TAVPacket; size: integer): integer; (* CAT#2 *)
  cdecl; external av__format;

function av_dup_packet (pkt: PAVPacket): integer;
  cdecl; external av__format;

(** * Free a packet
 *
 * @param pkt packet to free *)
procedure av_free_packet (var pkt: TAVPacket); (* CAT#2 *)

procedure av_register_image_format (img_fmt: PAVImageFormat);
    cdecl; external av__format;

function av_probe_image_format (pd: PAVProbeData): PAVImageFormat;
    cdecl; external av__format;

function guess_image_format (filename: pchar): PAVImageFormat;
    cdecl; external av__format;

function av_guess_image2_codec(filename: pchar): TCodecID;
    cdecl; external av__format;

function av_read_image (pb: PByteIOContext; filename: pchar;
                  fmt: PAVImageFormat;
                  alloc_cb: pointer; opaque: pointer): integer;
    cdecl; external av__format;

function av_write_image(pb: PByteIOContext; fmt: PAVImageFormat; img: PAVImageInfo): integer;
    cdecl; external av__format;

(* XXX: use automatic init with either ELF sections or C file parser *)
(* modules *)

//#include "rtp.h"

//#include "rtsp.h"

(* utils.c *)
  procedure av_register_input_format (format: PAVInputFormat);
    cdecl; external av__format;

  procedure av_register_output_format (format: PAVOutputFormat);
    cdecl; external av__format;

  function guess_stream_format (short_name: pchar; filename: pchar; mime_type: pchar): PAVOutputFormat;
    cdecl; external av__format;

  function guess_format(short_name: pchar; filename: pchar; mime_type: pchar): PAVOutputFormat;
    cdecl; external av__format;

  function av_guess_codec(fmt: PAVOutputFormat; short_name: pchar;
                          filename: pchar; mime_type: pchar; _type: TCodecType): TCodecID;
    cdecl; external av__format;

  procedure av_hex_dump (f: HFILE; buf: pchar; size: integer);
    cdecl; external av__format;
  procedure av_pkt_dump(f: HFILE; var pkt: TAVPacket; dump_payload: integer); (* CAT#2 *)
    cdecl; external av__format;

  procedure av_register_all ();
    cdecl; external av__format;


(* media file input *)
  function av_find_input_format (short_name: pchar): PAVInputFormat;
    cdecl; external av__format;
  function av_probe_input_format (pd: PAVProbeData; is_opened: integer): PAVInputFormat;
    cdecl; external av__format;
  function av_open_input_stream (ic_ptr: PAVFormatContext;
                         pb: PByteIOContext; filename: pchar;
                         fmt: PAVInputFormat; ap: PAVFormatParameters): integer;
    cdecl; external av__format;
(*** Open a media file as input. The codec 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 additionnal parameters needed when opening the file (NULL if default)
 * @return 0 if OK. AVERROR_xxx otherwise. *)

  function av_open_input_file (var ic_ptr: PAVFormatContext; filename: pchar;
                       fmt: PAVInputFormat; buf_size: integer;
                       ap: PAVFormatParameters): integer;
    cdecl; external av__format;

  (* no av_open for output, so applications will need this: *)
  function av_alloc_format_context (): PAVFormatContext;
    cdecl; external av__format;

const
  AVERROR_UNKNOWN     =(-1);  (* unknown error *)
  AVERROR_IO          =(-2);  (* i/o error *)
  AVERROR_NUMEXPECTED =(-3);  (* number syntax expected in filename *)
  AVERROR_INVALIDDATA =(-4);  (* invalid data found *)
  AVERROR_NOMEM       =(-5);  (* not enough memory *)
  AVERROR_NOFMT       =(-6);  (* unknown format *)
  AVERROR_NOTSUPP     =(-7);  (* operation not supported *)

(*** Read the beginning of a media file to get stream information. This
 * is useful for file formats with no headers such as MPEG. This
 * function also compute the real frame rate in case of mpeg2 repeat
 * frame mode.
 *
 * @param ic media file handle
 * @return >=0 if OK. AVERROR_xxx if error.
 * @todo let user decide somehow what information is needed so we dont waste time geting stuff the user doesnt need *)

  function av_find_stream_info (ic: PAVFormatContext): integer;
    cdecl; external av__format;
  function av_read_packet (s: PAVFormatContext; var pkt: TAVPacket): integer; (* CAT#2 *)
    cdecl; external av__format;
(*** Return the next frame of a stream.
 *
 * 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 AV_TIME_BASE unit (and guessed if the format cannot
 * provided 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 if error or end of file. *)

  function av_read_frame (s: PAVFormatContext; var pkt: TAVPacket): integer; (* CAT#2 *)
    cdecl; external av__format;
  function av_seek_frame (s: PAVFormatContext; stream_index: integer; timestamp: int64; flags: integer): integer;
    cdecl; external av__format;
  function av_read_play (s: PAVFormatContext): integer;
    cdecl; external av__format;
  function av_read_pause (s: PAVFormatContext): integer;
    cdecl; external av__format;
  procedure av_close_input_file (s: PAVFormatContext);
    cdecl; external av__format;
  function av_new_stream (s: PAVFormatContext; id: integer): PAVStream;
    cdecl; external av__format;
  procedure av_set_pts_info (s: PAVStream; pts_wrap_bits: integer;
                     pts_num: integer; pts_den: integer);
    cdecl; external av__format;

const
  AVSEEK_FLAG_BACKWARD =1; ///< seek backward
  AVSEEK_FLAG_BYTE     =2; ///< seeking based on position in bytes
  AVSEEK_FLAG_ANY      =4; ///< seek to any frame, even non keyframes

  function av_find_default_stream_index (s: PAVFormatContext): integer;
    cdecl; external av__format;
  function av_index_search_timestamp (st: PAVStream; timestamp: int64; flags: integer): integer;
    cdecl; external av__format;
  function av_add_index_entry (st: PAVStream; pos: int64; timestamp: int64;
                    distance: integer; flags: integer): integer;
    cdecl; external av__format;
  function av_seek_frame_binary (s: PAVFormatContext; stream_index: integer;
                   target_ts: int64; flags: integer): integer;
    cdecl; external av__format;

  procedure av_update_cur_dts (s: PAVFormatContext; ref_st: PAVStream;
                               timestamp: int64);
    cdecl; external av__format;

(* media file output *)
  function av_set_parameters (s: PAVFormatContext; ap: PAVFormatParameters): integer;
    cdecl; external av__format;

  function av_write_header (s: PAVFormatContext): integer;
    cdecl; external av__format;

  function av_write_frame(s: PAVFormatContext; var pkt: TAVPacket): integer;
    cdecl; external av__format; (* CAT#2 *)

  function av_interleaved_write_frame (s: PAVFormatContext; var pkt: TAVPacket): integer;
    cdecl; external av__format; (* CAT#2 *)

  function av_interleave_packet_per_dts(s: PAVFormatContext; _out: PAVPacket;
                                        pkt: PAVPacket; flush: integer): integer;
    cdecl; external av__format;
  function av_write_trailer(s: pAVFormatContext): integer;
    cdecl; external av__format;

  procedure dump_format(ic: PAVFormatContext; index: integer; url: pchar;
                 is_output: integer);
    cdecl; external av__format;

  function parse_image_size(width_ptr: PInteger; height_ptr: PInteger; str: pchar): integer;
    cdecl; external av__format;
  function parse_frame_rate (frame_rate: PInteger; frame_rate_base: PInteger; arg: pchar): integer;
    cdecl; external av__format;
  function parse_date(datestr: pchar; duration: integer): int64;
    cdecl; external av__format;
  function av_gettime (): int64;
    cdecl; external av__format;

(* ffm specific for ffserver *)
const
  FFM_PACKET_SIZE = 4096;

  function ffm_read_write_index (fd: integer): int64;
    cdecl; external av__format;

  procedure ffm_write_write_index(fd: integer; pos: int64);
    cdecl; external av__format;

  procedure ffm_set_write_index (s: PAVFormatContext; pos: int64; file_size: int64);
    cdecl; external av__format;

  function find_info_tag (arg: pchar; arg_size: integer; tag1: pchar; info: pchar): integer;
    cdecl; external av__format;

  function get_frame_filename(buf: pchar; buf_size: integer;
                       path: pchar; number: integer): integer;
    cdecl; external av__format;
  function filename_number_test (filename: pchar): integer;
    cdecl; external av__format;


(* grab specific *)
  function video_grab_init (): integer;
    cdecl; external av__format;
  function audio_init (): integer;
    cdecl; external av__format;

(* DV1394 *)
  function dv1394_init (): integer;
    cdecl; external av__format;
  function dc1394_init (): integer;
    cdecl; external av__format;

  function strstart(str: pchar; val: pchar; ptr: PPointer): integer;
    cdecl; external av__format;
  function stristart(str: pchar; val: pchar; ptr: PPointer): integer;
    cdecl; external av__format;
  procedure pstrcpy(buf: pchar; buf_size: integer; str: pchar);
    cdecl; external av__format;
  function pstrcat(buf: pchar; buf_size: integer; s: pchar): pchar;
    cdecl; external av__format;

  procedure __dynarray_add (tab_ptr: PPointer; nb_ptr: PInteger; elem: cardinal);
    cdecl; external av__format;


implementation

procedure av_init_packet (var pkt: TAVPacket);  (* CAT#2 + bug fix *)
begin
  with pkt do begin
    pts   := AV_NOPTS_VALUE;
    dts   := AV_NOPTS_VALUE;
    pos   := -1;
    duration := 0;
    flags := 0;
    stream_index := 0;
    destruct := @av_destruct_packet_nofree
  end
end;

procedure av_free_packet (var pkt: TAVPacket); (* CAT#2 *)
begin
  if @pkt.destruct <> nil then pkt.destruct (@pkt)
{  if (pkt <> nil) and (@pkt^.destruct <> nil) then
    pkt^.destruct (pkt)}
end;

end.