/*
  * Motion Pixels MVI Demuxer
  * Copyright (c) 2008 Gregory Montoir (cyx@users.sourceforge.net)
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg 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.
  *
  * FFmpeg 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 FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include "avformat.h"
 
 #define MVI_FRAC_BITS 10
 
 #define MVI_AUDIO_STREAM_INDEX 0
 #define MVI_VIDEO_STREAM_INDEX 1
 
 typedef struct MviDemuxContext {

     unsigned int (*get_int)(AVIOContext *);

     uint32_t audio_data_size;
     uint64_t audio_size_counter;
     uint64_t audio_frame_size;
     int audio_size_left;
     int video_frame_size;
 } MviDemuxContext;
 
 static int read_header(AVFormatContext *s, AVFormatParameters *ap)
 {
     MviDemuxContext *mvi = s->priv_data;

     AVIOContext *pb = s->pb;

     AVStream *ast, *vst;
     unsigned int version, frames_count, msecs_per_frame, player_version;
 
     ast = av_new_stream(s, 0);
     if (!ast)
         return AVERROR(ENOMEM);
 
     vst = av_new_stream(s, 0);
     if (!vst)
         return AVERROR(ENOMEM);
 
     vst->codec->extradata_size = 2;
     vst->codec->extradata = av_mallocz(2 + FF_INPUT_BUFFER_PADDING_SIZE);
 

     version                  = avio_r8(pb);
     vst->codec->extradata[0] = avio_r8(pb);
     vst->codec->extradata[1] = avio_r8(pb);
     frames_count             = avio_rl32(pb);
     msecs_per_frame          = avio_rl32(pb);
     vst->codec->width        = avio_rl16(pb);
     vst->codec->height       = avio_rl16(pb);
     avio_r8(pb);
     ast->codec->sample_rate  = avio_rl16(pb);
     mvi->audio_data_size     = avio_rl32(pb);
     avio_r8(pb);
     player_version           = avio_rl32(pb);
     avio_rl16(pb);
     avio_r8(pb);

 
     if (frames_count == 0 || mvi->audio_data_size == 0)
         return AVERROR_INVALIDDATA;
 
     if (version != 7 || player_version > 213) {
         av_log(s, AV_LOG_ERROR, "unhandled version (%d,%d)\n", version, player_version);
         return AVERROR_INVALIDDATA;
     }
 
     av_set_pts_info(ast, 64, 1, ast->codec->sample_rate);

     ast->codec->codec_type      = AVMEDIA_TYPE_AUDIO;

     ast->codec->codec_id        = CODEC_ID_PCM_U8;
     ast->codec->channels        = 1;

     ast->codec->bits_per_coded_sample = 8;

     ast->codec->bit_rate        = ast->codec->sample_rate * 8;
 
     av_set_pts_info(vst, 64, msecs_per_frame, 1000000);

     vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;

     vst->codec->codec_id   = CODEC_ID_MOTIONPIXELS;
 

     mvi->get_int = (vst->codec->width * vst->codec->height < (1 << 16)) ? avio_rl16 : avio_rl24;

 
     mvi->audio_frame_size   = ((uint64_t)mvi->audio_data_size << MVI_FRAC_BITS) / frames_count;
     mvi->audio_size_counter = (ast->codec->sample_rate * 830 / mvi->audio_frame_size - 1) * mvi->audio_frame_size;
     mvi->audio_size_left    = mvi->audio_data_size;
 
     return 0;
 }
 
 static int read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     int ret, count;
     MviDemuxContext *mvi = s->priv_data;

     AVIOContext *pb = s->pb;

 
     if (mvi->video_frame_size == 0) {
         mvi->video_frame_size = (mvi->get_int)(pb);
         if (mvi->audio_size_left == 0)
             return AVERROR(EIO);
         count = (mvi->audio_size_counter + mvi->audio_frame_size + 512) >> MVI_FRAC_BITS;
         if (count > mvi->audio_size_left)
             count = mvi->audio_size_left;
         if ((ret = av_get_packet(pb, pkt, count)) < 0)
             return ret;
         pkt->stream_index = MVI_AUDIO_STREAM_INDEX;
         mvi->audio_size_left -= count;
         mvi->audio_size_counter += mvi->audio_frame_size - (count << MVI_FRAC_BITS);
     } else {
         if ((ret = av_get_packet(pb, pkt, mvi->video_frame_size)) < 0)
             return ret;
         pkt->stream_index = MVI_VIDEO_STREAM_INDEX;
         mvi->video_frame_size = 0;
     }
     return 0;
 }
 

 AVInputFormat ff_mvi_demuxer = {

     "mvi",
     NULL_IF_CONFIG_SMALL("Motion Pixels MVI format"),
     sizeof(MviDemuxContext),
     NULL,
     read_header,
     read_packet,
     .extensions = "mvi"
 };