libavformat/mvi.c

   1 /*
   2  * Motion Pixels MVI Demuxer
   3  * Copyright (c) 2008 Gregory Montoir (cyx@users.sourceforge.net)
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "libavutil/channel_layout.h"
  23 #include "avformat.h"
  24 #include "internal.h"
  25
  26 #define MVI_FRAC_BITS 10
  27
  28 #define MVI_AUDIO_STREAM_INDEX 0
  29 #define MVI_VIDEO_STREAM_INDEX 1
  30
  31 typedef struct MviDemuxContext {
  32     unsigned int (*get_int)(AVIOContext *);
  33     uint32_t audio_data_size;
  34     uint64_t audio_size_counter;
  35     uint64_t audio_frame_size;
  36     int audio_size_left;
  37     int video_frame_size;
  38 } MviDemuxContext;
  39
  40 static int read_header(AVFormatContext *s)
  41 {
  42     MviDemuxContext *mvi = s->priv_data;
  43     AVIOContext *pb = s->pb;
  44     AVStream *ast, *vst;
  45     unsigned int version, frames_count, msecs_per_frame, player_version;
  46
  47     ast = avformat_new_stream(s, NULL);
  48     if (!ast)
  49         return AVERROR(ENOMEM);
  50
  51     vst = avformat_new_stream(s, NULL);
  52     if (!vst)
  53         return AVERROR(ENOMEM);
  54
  55     vst->codec->extradata_size = 2;
  56     vst->codec->extradata = av_mallocz(2 + FF_INPUT_BUFFER_PADDING_SIZE);
  57
  58     version                  = avio_r8(pb);
  59     vst->codec->extradata[0] = avio_r8(pb);
  60     vst->codec->extradata[1] = avio_r8(pb);
  61     frames_count             = avio_rl32(pb);
  62     msecs_per_frame          = avio_rl32(pb);
  63     vst->codec->width        = avio_rl16(pb);
  64     vst->codec->height       = avio_rl16(pb);
  65     avio_r8(pb);
  66     ast->codec->sample_rate  = avio_rl16(pb);
  67     mvi->audio_data_size     = avio_rl32(pb);
  68     avio_r8(pb);
  69     player_version           = avio_rl32(pb);
  70     avio_rl16(pb);
  71     avio_r8(pb);
  72
  73     if (frames_count == 0 || mvi->audio_data_size == 0)
  74         return AVERROR_INVALIDDATA;
  75
  76     if (version != 7 || player_version > 213) {
  77         av_log(s, AV_LOG_ERROR, "unhandled version (%d,%d)\n", version, player_version);
  78         return AVERROR_INVALIDDATA;
  79     }
  80
  81     avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
  82     ast->codec->codec_type      = AVMEDIA_TYPE_AUDIO;
  83     ast->codec->codec_id        = AV_CODEC_ID_PCM_U8;
  84     ast->codec->channels        = 1;
  85     ast->codec->channel_layout  = AV_CH_LAYOUT_MONO;
  86     ast->codec->bits_per_coded_sample = 8;
  87     ast->codec->bit_rate        = ast->codec->sample_rate * 8;
  88
  89     avpriv_set_pts_info(vst, 64, msecs_per_frame, 1000000);
  90     vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
  91     vst->codec->codec_id   = AV_CODEC_ID_MOTIONPIXELS;
  92
  93     mvi->get_int = (vst->codec->width * vst->codec->height < (1 << 16)) ? avio_rl16 : avio_rl24;
  94
  95     mvi->audio_frame_size   = ((uint64_t)mvi->audio_data_size << MVI_FRAC_BITS) / frames_count;
  96     mvi->audio_size_counter = (ast->codec->sample_rate * 830 / mvi->audio_frame_size - 1) * mvi->audio_frame_size;
  97     mvi->audio_size_left    = mvi->audio_data_size;
  98
  99     return 0;
 100 }
 101
 102 static int read_packet(AVFormatContext *s, AVPacket *pkt)
 103 {
 104     int ret, count;
 105     MviDemuxContext *mvi = s->priv_data;
 106     AVIOContext *pb = s->pb;
 107
 108     if (mvi->video_frame_size == 0) {
 109         mvi->video_frame_size = (mvi->get_int)(pb);
 110         if (mvi->audio_size_left == 0)
 111             return AVERROR(EIO);
 112         count = (mvi->audio_size_counter + mvi->audio_frame_size + 512) >> MVI_FRAC_BITS;
 113         if (count > mvi->audio_size_left)
 114             count = mvi->audio_size_left;
 115         if ((ret = av_get_packet(pb, pkt, count)) < 0)
 116             return ret;
 117         pkt->stream_index = MVI_AUDIO_STREAM_INDEX;
 118         mvi->audio_size_left -= count;
 119         mvi->audio_size_counter += mvi->audio_frame_size - (count << MVI_FRAC_BITS);
 120     } else {
 121         if ((ret = av_get_packet(pb, pkt, mvi->video_frame_size)) < 0)
 122             return ret;
 123         pkt->stream_index = MVI_VIDEO_STREAM_INDEX;
 124         mvi->video_frame_size = 0;
 125     }
 126     return 0;
 127 }
 128
 129 AVInputFormat ff_mvi_demuxer = {
 130     .name           = "mvi",
 131     .long_name      = NULL_IF_CONFIG_SMALL("Motion Pixels MVI"),
 132     .priv_data_size = sizeof(MviDemuxContext),
 133     .read_header    = read_header,
 134     .read_packet    = read_packet,
 135     .extensions     = "mvi",
 136 };