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 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 #include "avformat.h"
  23
  24 #define MVI_FRAC_BITS 10
  25
  26 #define MVI_AUDIO_STREAM_INDEX 0
  27 #define MVI_VIDEO_STREAM_INDEX 1
  28
  29 typedef struct MviDemuxContext {
  30     unsigned int (*get_int)(ByteIOContext *);
  31     uint32_t audio_data_size;
  32     uint64_t audio_size_counter;
  33     uint64_t audio_frame_size;
  34     int audio_size_left;
  35     int video_frame_size;
  36 } MviDemuxContext;
  37
  38 static int read_header(AVFormatContext *s, AVFormatParameters *ap)
  39 {
  40     MviDemuxContext *mvi = s->priv_data;
  41     ByteIOContext *pb = s->pb;
  42     AVStream *ast, *vst;
  43     unsigned int version, frames_count, msecs_per_frame, player_version;
  44
  45     ast = av_new_stream(s, 0);
  46     if (!ast)
  47         return AVERROR(ENOMEM);
  48
  49     vst = av_new_stream(s, 0);
  50     if (!vst)
  51         return AVERROR(ENOMEM);
  52
  53     vst->codec->extradata_size = 2;
  54     vst->codec->extradata = av_mallocz(2 + FF_INPUT_BUFFER_PADDING_SIZE);
  55
  56     version                  = get_byte(pb);
  57     vst->codec->extradata[0] = get_byte(pb);
  58     vst->codec->extradata[1] = get_byte(pb);
  59     frames_count             = get_le32(pb);
  60     msecs_per_frame          = get_le32(pb);
  61     vst->codec->width        = get_le16(pb);
  62     vst->codec->height       = get_le16(pb);
  63     get_byte(pb);
  64     ast->codec->sample_rate  = get_le16(pb);
  65     mvi->audio_data_size     = get_le32(pb);
  66     get_byte(pb);
  67     player_version           = get_le32(pb);
  68     get_le16(pb);
  69     get_byte(pb);
  70
  71     if (frames_count == 0 || mvi->audio_data_size == 0)
  72         return AVERROR_INVALIDDATA;
  73
  74     if (version != 7 || player_version > 213) {
  75         av_log(s, AV_LOG_ERROR, "unhandled version (%d,%d)\n", version, player_version);
  76         return AVERROR_INVALIDDATA;
  77     }
  78
  79     av_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
  80     ast->codec->codec_type      = CODEC_TYPE_AUDIO;
  81     ast->codec->codec_id        = CODEC_ID_PCM_U8;
  82     ast->codec->channels        = 1;
  83     ast->codec->bits_per_coded_sample = 8;
  84     ast->codec->bit_rate        = ast->codec->sample_rate * 8;
  85
  86     av_set_pts_info(vst, 64, msecs_per_frame, 1000000);
  87     vst->codec->codec_type = CODEC_TYPE_VIDEO;
  88     vst->codec->codec_id   = CODEC_ID_MOTIONPIXELS;
  89     vst->codec->pix_fmt    = PIX_FMT_RGB555;
  90
  91     mvi->get_int = (vst->codec->width * vst->codec->height < (1 << 16)) ? get_le16 : get_le24;
  92
  93     mvi->audio_frame_size   = ((uint64_t)mvi->audio_data_size << MVI_FRAC_BITS) / frames_count;
  94     mvi->audio_size_counter = (ast->codec->sample_rate * 830 / mvi->audio_frame_size - 1) * mvi->audio_frame_size;
  95     mvi->audio_size_left    = mvi->audio_data_size;
  96
  97     return 0;
  98 }
  99
 100 static int read_packet(AVFormatContext *s, AVPacket *pkt)
 101 {
 102     int ret, count;
 103     MviDemuxContext *mvi = s->priv_data;
 104     ByteIOContext *pb = s->pb;
 105
 106     if (mvi->video_frame_size == 0) {
 107         mvi->video_frame_size = (mvi->get_int)(pb);
 108         if (mvi->audio_size_left == 0)
 109             return AVERROR(EIO);
 110         count = (mvi->audio_size_counter + mvi->audio_frame_size + 512) >> MVI_FRAC_BITS;
 111         if (count > mvi->audio_size_left)
 112             count = mvi->audio_size_left;
 113         if ((ret = av_get_packet(pb, pkt, count)) < 0)
 114             return ret;
 115         pkt->stream_index = MVI_AUDIO_STREAM_INDEX;
 116         mvi->audio_size_left -= count;
 117         mvi->audio_size_counter += mvi->audio_frame_size - (count << MVI_FRAC_BITS);
 118     } else {
 119         if ((ret = av_get_packet(pb, pkt, mvi->video_frame_size)) < 0)
 120             return ret;
 121         pkt->stream_index = MVI_VIDEO_STREAM_INDEX;
 122         mvi->video_frame_size = 0;
 123     }
 124     return 0;
 125 }
 126
 127 AVInputFormat mvi_demuxer = {
 128     "mvi",
 129     NULL_IF_CONFIG_SMALL("Motion Pixels MVI format"),
 130     sizeof(MviDemuxContext),
 131     NULL,
 132     read_header,
 133     read_packet,
 134     .extensions = "mvi"
 135 };