Subversion Repositories Kolibri OS

Rev

Blame | Last modification | View Log | RSS feed

  1. /*
  2.  * Brute Force & Ignorance (BFI) demuxer
  3.  * Copyright (c) 2008 Sisir Koppaka
  4.  *
  5.  * This file is part of FFmpeg.
  6.  *
  7.  * FFmpeg is free software; you can redistribute it and/or
  8.  * modify it under the terms of the GNU Lesser General Public
  9.  * License as published by the Free Software Foundation; either
  10.  * version 2.1 of the License, or (at your option) any later version.
  11.  *
  12.  * FFmpeg is distributed in the hope that it will be useful,
  13.  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15.  * Lesser General Public License for more details.
  16.  *
  17.  * You should have received a copy of the GNU Lesser General Public
  18.  * License along with FFmpeg; if not, write to the Free Software
  19.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20.  */
  21.  
  22. /**
  23.  * @file
  24.  * @brief Brute Force & Ignorance (.bfi) file demuxer
  25.  * @author Sisir Koppaka ( sisir.koppaka at gmail dot com )
  26.  * @see http://wiki.multimedia.cx/index.php?title=BFI
  27.  */
  28.  
  29. #include "libavutil/channel_layout.h"
  30. #include "libavutil/intreadwrite.h"
  31. #include "avformat.h"
  32. #include "internal.h"
  33.  
  34. typedef struct BFIContext {
  35.     int nframes;
  36.     int audio_frame;
  37.     int video_frame;
  38.     int video_size;
  39.     int avflag;
  40. } BFIContext;
  41.  
  42. static int bfi_probe(AVProbeData * p)
  43. {
  44.     /* Check file header */
  45.     if (AV_RL32(p->buf) == MKTAG('B', 'F', '&', 'I'))
  46.         return AVPROBE_SCORE_MAX;
  47.     else
  48.         return 0;
  49. }
  50.  
  51. static int bfi_read_header(AVFormatContext * s)
  52. {
  53.     BFIContext *bfi = s->priv_data;
  54.     AVIOContext *pb = s->pb;
  55.     AVStream *vstream;
  56.     AVStream *astream;
  57.     int fps, chunk_header;
  58.  
  59.     /* Initialize the video codec... */
  60.     vstream = avformat_new_stream(s, NULL);
  61.     if (!vstream)
  62.         return AVERROR(ENOMEM);
  63.  
  64.     /* Initialize the audio codec... */
  65.     astream = avformat_new_stream(s, NULL);
  66.     if (!astream)
  67.         return AVERROR(ENOMEM);
  68.  
  69.     /* Set the total number of frames. */
  70.     avio_skip(pb, 8);
  71.     chunk_header           = avio_rl32(pb);
  72.     bfi->nframes           = avio_rl32(pb);
  73.     avio_rl32(pb);
  74.     avio_rl32(pb);
  75.     avio_rl32(pb);
  76.     fps                    = avio_rl32(pb);
  77.     avio_skip(pb, 12);
  78.     vstream->codec->width  = avio_rl32(pb);
  79.     vstream->codec->height = avio_rl32(pb);
  80.  
  81.     /*Load the palette to extradata */
  82.     avio_skip(pb, 8);
  83.     vstream->codec->extradata      = av_malloc(768);
  84.     if (!vstream->codec->extradata)
  85.         return AVERROR(ENOMEM);
  86.     vstream->codec->extradata_size = 768;
  87.     avio_read(pb, vstream->codec->extradata,
  88.                vstream->codec->extradata_size);
  89.  
  90.     astream->codec->sample_rate = avio_rl32(pb);
  91.  
  92.     /* Set up the video codec... */
  93.     avpriv_set_pts_info(vstream, 32, 1, fps);
  94.     vstream->codec->codec_type = AVMEDIA_TYPE_VIDEO;
  95.     vstream->codec->codec_id   = AV_CODEC_ID_BFI;
  96.     vstream->codec->pix_fmt    = AV_PIX_FMT_PAL8;
  97.     vstream->nb_frames         =
  98.     vstream->duration          = bfi->nframes;
  99.  
  100.     /* Set up the audio codec now... */
  101.     astream->codec->codec_type      = AVMEDIA_TYPE_AUDIO;
  102.     astream->codec->codec_id        = AV_CODEC_ID_PCM_U8;
  103.     astream->codec->channels        = 1;
  104.     astream->codec->channel_layout  = AV_CH_LAYOUT_MONO;
  105.     astream->codec->bits_per_coded_sample = 8;
  106.     astream->codec->bit_rate        =
  107.         astream->codec->sample_rate * astream->codec->bits_per_coded_sample;
  108.     avio_seek(pb, chunk_header - 3, SEEK_SET);
  109.     avpriv_set_pts_info(astream, 64, 1, astream->codec->sample_rate);
  110.     return 0;
  111. }
  112.  
  113.  
  114. static int bfi_read_packet(AVFormatContext * s, AVPacket * pkt)
  115. {
  116.     BFIContext *bfi = s->priv_data;
  117.     AVIOContext *pb = s->pb;
  118.     int ret, audio_offset, video_offset, chunk_size, audio_size = 0;
  119.     if (bfi->nframes == 0 || avio_feof(pb)) {
  120.         return AVERROR_EOF;
  121.     }
  122.  
  123.     /* If all previous chunks were completely read, then find a new one... */
  124.     if (!bfi->avflag) {
  125.         uint32_t state = 0;
  126.         while(state != MKTAG('S','A','V','I')){
  127.             if (avio_feof(pb))
  128.                 return AVERROR(EIO);
  129.             state = 256*state + avio_r8(pb);
  130.         }
  131.         /* Now that the chunk's location is confirmed, we proceed... */
  132.         chunk_size      = avio_rl32(pb);
  133.         avio_rl32(pb);
  134.         audio_offset    = avio_rl32(pb);
  135.         avio_rl32(pb);
  136.         video_offset    = avio_rl32(pb);
  137.         audio_size      = video_offset - audio_offset;
  138.         bfi->video_size = chunk_size - video_offset;
  139.         if (audio_size < 0 || bfi->video_size < 0) {
  140.             av_log(s, AV_LOG_ERROR, "Invalid audio/video offsets or chunk size\n");
  141.             return AVERROR_INVALIDDATA;
  142.         }
  143.  
  144.         //Tossing an audio packet at the audio decoder.
  145.         ret = av_get_packet(pb, pkt, audio_size);
  146.         if (ret < 0)
  147.             return ret;
  148.  
  149.         pkt->pts          = bfi->audio_frame;
  150.         bfi->audio_frame += ret;
  151.     } else if (bfi->video_size > 0) {
  152.  
  153.         //Tossing a video packet at the video decoder.
  154.         ret = av_get_packet(pb, pkt, bfi->video_size);
  155.         if (ret < 0)
  156.             return ret;
  157.  
  158.         pkt->pts          = bfi->video_frame;
  159.         bfi->video_frame += ret / bfi->video_size;
  160.  
  161.         /* One less frame to read. A cursory decrement. */
  162.         bfi->nframes--;
  163.     } else {
  164.         /* Empty video packet */
  165.         ret = AVERROR(EAGAIN);
  166.     }
  167.  
  168.     bfi->avflag       = !bfi->avflag;
  169.     pkt->stream_index = bfi->avflag;
  170.     return ret;
  171. }
  172.  
  173. AVInputFormat ff_bfi_demuxer = {
  174.     .name           = "bfi",
  175.     .long_name      = NULL_IF_CONFIG_SMALL("Brute Force & Ignorance"),
  176.     .priv_data_size = sizeof(BFIContext),
  177.     .read_probe     = bfi_probe,
  178.     .read_header    = bfi_read_header,
  179.     .read_packet    = bfi_read_packet,
  180. };
  181.