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libavformat/avisynth.c

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00001 /*
00002  * AVISynth support
00003  * Copyright (c) 2006 DivX, Inc.
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "avformat.h"
00023 #include "internal.h"
00024 #include "riff.h"
00025 
00026 #include <windows.h>
00027 #include <vfw.h>
00028 
00029 typedef struct {
00030   PAVISTREAM handle;
00031   AVISTREAMINFO info;
00032   DWORD read;
00033   LONG chunck_size;
00034   LONG chunck_samples;
00035 } AVISynthStream;
00036 
00037 typedef struct {
00038   PAVIFILE file;
00039   AVISynthStream *streams;
00040   int nb_streams;
00041   int next_stream;
00042 } AVISynthContext;
00043 
00044 static int avisynth_read_header(AVFormatContext *s, AVFormatParameters *ap)
00045 {
00046   AVISynthContext *avs = s->priv_data;
00047   HRESULT res;
00048   AVIFILEINFO info;
00049   DWORD id;
00050   AVStream *st;
00051   AVISynthStream *stream;
00052 
00053   AVIFileInit();
00054 
00055   res = AVIFileOpen(&avs->file, s->filename, OF_READ|OF_SHARE_DENY_WRITE, NULL);
00056   if (res != S_OK)
00057     {
00058       av_log(s, AV_LOG_ERROR, "AVIFileOpen failed with error %ld", res);
00059       AVIFileExit();
00060       return -1;
00061     }
00062 
00063   res = AVIFileInfo(avs->file, &info, sizeof(info));
00064   if (res != S_OK)
00065     {
00066       av_log(s, AV_LOG_ERROR, "AVIFileInfo failed with error %ld", res);
00067       AVIFileExit();
00068       return -1;
00069     }
00070 
00071   avs->streams = av_mallocz(info.dwStreams * sizeof(AVISynthStream));
00072 
00073   for (id=0; id<info.dwStreams; id++)
00074     {
00075       stream = &avs->streams[id];
00076       stream->read = 0;
00077       if (AVIFileGetStream(avs->file, &stream->handle, 0, id) == S_OK)
00078         {
00079           if (AVIStreamInfo(stream->handle, &stream->info, sizeof(stream->info)) == S_OK)
00080             {
00081               if (stream->info.fccType == streamtypeAUDIO)
00082                 {
00083                   WAVEFORMATEX wvfmt;
00084                   LONG struct_size = sizeof(WAVEFORMATEX);
00085                   if (AVIStreamReadFormat(stream->handle, 0, &wvfmt, &struct_size) != S_OK)
00086                     continue;
00087 
00088                   st = avformat_new_stream(s, NULL);
00089                   st->id = id;
00090                   st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00091 
00092                   st->codec->block_align = wvfmt.nBlockAlign;
00093                   st->codec->channels = wvfmt.nChannels;
00094                   st->codec->sample_rate = wvfmt.nSamplesPerSec;
00095                   st->codec->bit_rate = wvfmt.nAvgBytesPerSec * 8;
00096                   st->codec->bits_per_coded_sample = wvfmt.wBitsPerSample;
00097 
00098                   stream->chunck_samples = wvfmt.nSamplesPerSec * (uint64_t)info.dwScale / (uint64_t)info.dwRate;
00099                   stream->chunck_size = stream->chunck_samples * wvfmt.nChannels * wvfmt.wBitsPerSample / 8;
00100 
00101                   st->codec->codec_tag = wvfmt.wFormatTag;
00102                   st->codec->codec_id = ff_wav_codec_get_id(wvfmt.wFormatTag, st->codec->bits_per_coded_sample);
00103                 }
00104               else if (stream->info.fccType == streamtypeVIDEO)
00105                 {
00106                   BITMAPINFO imgfmt;
00107                   LONG struct_size = sizeof(BITMAPINFO);
00108 
00109                   stream->chunck_size = stream->info.dwSampleSize;
00110                   stream->chunck_samples = 1;
00111 
00112                   if (AVIStreamReadFormat(stream->handle, 0, &imgfmt, &struct_size) != S_OK)
00113                     continue;
00114 
00115                   st = avformat_new_stream(s, NULL);
00116                   st->id = id;
00117                   st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00118                   st->r_frame_rate.num = stream->info.dwRate;
00119                   st->r_frame_rate.den = stream->info.dwScale;
00120 
00121                   st->codec->width = imgfmt.bmiHeader.biWidth;
00122                   st->codec->height = imgfmt.bmiHeader.biHeight;
00123 
00124                   st->codec->bits_per_coded_sample = imgfmt.bmiHeader.biBitCount;
00125                   st->codec->bit_rate = (uint64_t)stream->info.dwSampleSize * (uint64_t)stream->info.dwRate * 8 / (uint64_t)stream->info.dwScale;
00126                   st->codec->codec_tag = imgfmt.bmiHeader.biCompression;
00127                   st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, imgfmt.bmiHeader.biCompression);
00128 
00129                   st->duration = stream->info.dwLength;
00130                 }
00131               else
00132                 {
00133                   AVIStreamRelease(stream->handle);
00134                   continue;
00135                 }
00136 
00137               avs->nb_streams++;
00138 
00139               st->codec->stream_codec_tag = stream->info.fccHandler;
00140 
00141               avpriv_set_pts_info(st, 64, info.dwScale, info.dwRate);
00142               st->start_time = stream->info.dwStart;
00143             }
00144         }
00145     }
00146 
00147   return 0;
00148 }
00149 
00150 static int avisynth_read_packet(AVFormatContext *s, AVPacket *pkt)
00151 {
00152   AVISynthContext *avs = s->priv_data;
00153   HRESULT res;
00154   AVISynthStream *stream;
00155   int stream_id = avs->next_stream;
00156   LONG read_size;
00157 
00158   // handle interleaving manually...
00159   stream = &avs->streams[stream_id];
00160 
00161   if (stream->read >= stream->info.dwLength)
00162     return AVERROR(EIO);
00163 
00164   if (av_new_packet(pkt, stream->chunck_size))
00165     return AVERROR(EIO);
00166   pkt->stream_index = stream_id;
00167   pkt->pts = avs->streams[stream_id].read / avs->streams[stream_id].chunck_samples;
00168 
00169   res = AVIStreamRead(stream->handle, stream->read, stream->chunck_samples, pkt->data, stream->chunck_size, &read_size, NULL);
00170 
00171   pkt->pts = stream->read;
00172   pkt->size = read_size;
00173 
00174   stream->read += stream->chunck_samples;
00175 
00176   // prepare for the next stream to read
00177   do {
00178     avs->next_stream = (avs->next_stream+1) % avs->nb_streams;
00179   } while (avs->next_stream != stream_id && s->streams[avs->next_stream]->discard >= AVDISCARD_ALL);
00180 
00181   return (res == S_OK) ? pkt->size : -1;
00182 }
00183 
00184 static int avisynth_read_close(AVFormatContext *s)
00185 {
00186   AVISynthContext *avs = s->priv_data;
00187   int i;
00188 
00189   for (i=0;i<avs->nb_streams;i++)
00190     {
00191       AVIStreamRelease(avs->streams[i].handle);
00192     }
00193 
00194   av_free(avs->streams);
00195   AVIFileRelease(avs->file);
00196   AVIFileExit();
00197   return 0;
00198 }
00199 
00200 static int avisynth_read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags)
00201 {
00202   AVISynthContext *avs = s->priv_data;
00203   int stream_id;
00204 
00205   for (stream_id = 0; stream_id < avs->nb_streams; stream_id++)
00206     {
00207       avs->streams[stream_id].read = pts * avs->streams[stream_id].chunck_samples;
00208     }
00209 
00210   return 0;
00211 }
00212 
00213 AVInputFormat ff_avisynth_demuxer = {
00214     .name           = "avs",
00215     .long_name      = NULL_IF_CONFIG_SMALL("AVISynth"),
00216     .priv_data_size = sizeof(AVISynthContext),
00217     .read_header    = avisynth_read_header,
00218     .read_packet    = avisynth_read_packet,
00219     .read_close     = avisynth_read_close,
00220     .read_seek      = avisynth_read_seek,
00221     .extensions     = "avs",
00222 };
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