PeerStreamer

/*

 * AVISynth support for ffmpeg system

 * Copyright (c) 2006 DivX, Inc.

 *

 * This file is part of Libav.

 *

 * Libav 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.

 *

 * Libav 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 Libav; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#include "avformat.h"

#include "riff.h"

#include <windows.h>

#include <vfw.h>

typedef struct {

  PAVISTREAM handle;

  AVISTREAMINFO info;

  DWORD read;

  LONG chunck_size;

  LONG chunck_samples;

} AVISynthStream;

typedef struct {

  PAVIFILE file;

  AVISynthStream *streams;

  int nb_streams;

  int next_stream;

} AVISynthContext;

static int avisynth_read_header(AVFormatContext *s, AVFormatParameters *ap)

{

  AVISynthContext *avs = s->priv_data;

  HRESULT res;

  AVIFILEINFO info;

  DWORD id;

  AVStream *st;

  AVISynthStream *stream;

  AVIFileInit();

  res = AVIFileOpen(&avs->file, s->filename, OF_READ|OF_SHARE_DENY_WRITE, NULL);

  if (res != S_OK)

    {

      av_log(s, AV_LOG_ERROR, "AVIFileOpen failed with error %ld", res);

      AVIFileExit();

      return -1;

    }

  res = AVIFileInfo(avs->file, &info, sizeof(info));

  if (res != S_OK)

    {

      av_log(s, AV_LOG_ERROR, "AVIFileInfo failed with error %ld", res);

      AVIFileExit();

      return -1;

    }

  avs->streams = av_mallocz(info.dwStreams * sizeof(AVISynthStream));

  for (id=0; id<info.dwStreams; id++)

    {

      stream = &avs->streams[id];

      stream->read = 0;

      if (AVIFileGetStream(avs->file, &stream->handle, 0, id) == S_OK)

        {

          if (AVIStreamInfo(stream->handle, &stream->info, sizeof(stream->info)) == S_OK)

            {

              if (stream->info.fccType == streamtypeAUDIO)

                {

                  WAVEFORMATEX wvfmt;

                  LONG struct_size = sizeof(WAVEFORMATEX);

                  if (AVIStreamReadFormat(stream->handle, 0, &wvfmt, &struct_size) != S_OK)

                    continue;

                  st = av_new_stream(s, id);

                  st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

                  st->codec->block_align = wvfmt.nBlockAlign;

                  st->codec->channels = wvfmt.nChannels;

                  st->codec->sample_rate = wvfmt.nSamplesPerSec;

                  st->codec->bit_rate = wvfmt.nAvgBytesPerSec * 8;

                  st->codec->bits_per_coded_sample = wvfmt.wBitsPerSample;

                  stream->chunck_samples = wvfmt.nSamplesPerSec * (uint64_t)info.dwScale / (uint64_t)info.dwRate;

                  stream->chunck_size = stream->chunck_samples * wvfmt.nChannels * wvfmt.wBitsPerSample / 8;

                  st->codec->codec_tag = wvfmt.wFormatTag;

                  st->codec->codec_id = ff_wav_codec_get_id(wvfmt.wFormatTag, st->codec->bits_per_coded_sample);

                }

              else if (stream->info.fccType == streamtypeVIDEO)

                {

                  BITMAPINFO imgfmt;

                  LONG struct_size = sizeof(BITMAPINFO);

                  stream->chunck_size = stream->info.dwSampleSize;

                  stream->chunck_samples = 1;

                  if (AVIStreamReadFormat(stream->handle, 0, &imgfmt, &struct_size) != S_OK)

                    continue;

                  st = av_new_stream(s, id);

                  st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

                  st->r_frame_rate.num = stream->info.dwRate;

                  st->r_frame_rate.den = stream->info.dwScale;

                  st->codec->width = imgfmt.bmiHeader.biWidth;

                  st->codec->height = imgfmt.bmiHeader.biHeight;

                  st->codec->bits_per_coded_sample = imgfmt.bmiHeader.biBitCount;

                  st->codec->bit_rate = (uint64_t)stream->info.dwSampleSize * (uint64_t)stream->info.dwRate * 8 / (uint64_t)stream->info.dwScale;

                  st->codec->codec_tag = imgfmt.bmiHeader.biCompression;

                  st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, imgfmt.bmiHeader.biCompression);

                  st->duration = stream->info.dwLength;

                }

              else

                {

                  AVIStreamRelease(stream->handle);

                  continue;

                }

              avs->nb_streams++;

              st->codec->stream_codec_tag = stream->info.fccHandler;

              av_set_pts_info(st, 64, info.dwScale, info.dwRate);

              st->start_time = stream->info.dwStart;

            }

        }

    }

  return 0;

}

static int avisynth_read_packet(AVFormatContext *s, AVPacket *pkt)

{

  AVISynthContext *avs = s->priv_data;

  HRESULT res;

  AVISynthStream *stream;

  int stream_id = avs->next_stream;

  LONG read_size;

  // handle interleaving manually...

  stream = &avs->streams[stream_id];

  if (stream->read >= stream->info.dwLength)

    return AVERROR(EIO);

  if (av_new_packet(pkt, stream->chunck_size))

    return AVERROR(EIO);

  pkt->stream_index = stream_id;

  pkt->pts = avs->streams[stream_id].read / avs->streams[stream_id].chunck_samples;

  res = AVIStreamRead(stream->handle, stream->read, stream->chunck_samples, pkt->data, stream->chunck_size, &read_size, NULL);

  pkt->pts = stream->read;

  pkt->size = read_size;

  stream->read += stream->chunck_samples;

  // prepare for the next stream to read

  do {

    avs->next_stream = (avs->next_stream+1) % avs->nb_streams;

  } while (avs->next_stream != stream_id && s->streams[avs->next_stream]->discard >= AVDISCARD_ALL);

  return (res == S_OK) ? pkt->size : -1;

}

static int avisynth_read_close(AVFormatContext *s)

{

  AVISynthContext *avs = s->priv_data;

  int i;

  for (i=0;i<avs->nb_streams;i++)

    {

      AVIStreamRelease(avs->streams[i].handle);

    }

  av_free(avs->streams);

  AVIFileRelease(avs->file);

  AVIFileExit();

  return 0;

}

static int avisynth_read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags)

{

  AVISynthContext *avs = s->priv_data;

  int stream_id;

  for (stream_id = 0; stream_id < avs->nb_streams; stream_id++)

    {

      avs->streams[stream_id].read = pts * avs->streams[stream_id].chunck_samples;

    }

  return 0;

}

AVInputFormat ff_avisynth_demuxer = {

  "avs",

  NULL_IF_CONFIG_SMALL("AVISynth"),

  sizeof(AVISynthContext),

  NULL,

  avisynth_read_header,

  avisynth_read_packet,

  avisynth_read_close,

  avisynth_read_seek,

  NULL,

  0,

  "avs",

};