FFmpeg: libavformat/sierravmd.c Source File

00001 /*
00002  * Sierra VMD Format Demuxer
00003  * Copyright (c) 2004 The ffmpeg Project
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00030 #include "libavutil/intreadwrite.h"
00031 #include "avformat.h"
00032 #include "internal.h"
00033 #include "avio_internal.h"
00034 
00035 #define VMD_HEADER_SIZE 0x0330
00036 #define BYTES_PER_FRAME_RECORD 16
00037 
00038 typedef struct {
00039   int stream_index;
00040   int64_t frame_offset;
00041   unsigned int frame_size;
00042   int64_t pts;
00043   int keyframe;
00044   unsigned char frame_record[BYTES_PER_FRAME_RECORD];
00045 } vmd_frame;
00046 
00047 typedef struct VmdDemuxContext {
00048     int video_stream_index;
00049     int audio_stream_index;
00050 
00051     unsigned int frame_count;
00052     unsigned int frames_per_block;
00053     vmd_frame *frame_table;
00054     unsigned int current_frame;
00055     int is_indeo3;
00056 
00057     int sample_rate;
00058     int64_t audio_sample_counter;
00059     int skiphdr;
00060 
00061     unsigned char vmd_header[VMD_HEADER_SIZE];
00062 } VmdDemuxContext;
00063 
00064 static int vmd_probe(AVProbeData *p)
00065 {
00066     int w, h;
00067     if (p->buf_size < 16)
00068         return 0;
00069     /* check if the first 2 bytes of the file contain the appropriate size
00070      * of a VMD header chunk */
00071     if (AV_RL16(&p->buf[0]) != VMD_HEADER_SIZE - 2)
00072         return 0;
00073     w = AV_RL16(&p->buf[12]);
00074     h = AV_RL16(&p->buf[14]);
00075     if (!w || w > 2048 || !h || h > 2048)
00076         return 0;
00077 
00078     /* only return half certainty since this check is a bit sketchy */
00079     return AVPROBE_SCORE_MAX / 2;
00080 }
00081 
00082 static int vmd_read_header(AVFormatContext *s,
00083                            AVFormatParameters *ap)
00084 {
00085     VmdDemuxContext *vmd = s->priv_data;
00086     AVIOContext *pb = s->pb;
00087     AVStream *st = NULL, *vst;
00088     unsigned int toc_offset;
00089     unsigned char *raw_frame_table;
00090     int raw_frame_table_size;
00091     int64_t current_offset;
00092     int i, j;
00093     unsigned int total_frames;
00094     int64_t current_audio_pts = 0;
00095     unsigned char chunk[BYTES_PER_FRAME_RECORD];
00096     int num, den;
00097     int sound_buffers;
00098 
00099     /* fetch the main header, including the 2 header length bytes */
00100     avio_seek(pb, 0, SEEK_SET);
00101     if (avio_read(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)
00102         return AVERROR(EIO);
00103 
00104     if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3')
00105         vmd->is_indeo3 = 1;
00106     else
00107         vmd->is_indeo3 = 0;
00108     /* start up the decoders */
00109     vst = avformat_new_stream(s, NULL);
00110     if (!vst)
00111         return AVERROR(ENOMEM);
00112     avpriv_set_pts_info(vst, 33, 1, 10);
00113     vmd->video_stream_index = vst->index;
00114     vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00115     vst->codec->codec_id = vmd->is_indeo3 ? CODEC_ID_INDEO3 : CODEC_ID_VMDVIDEO;
00116     vst->codec->codec_tag = 0;  /* no fourcc */
00117     vst->codec->width = AV_RL16(&vmd->vmd_header[12]);
00118     vst->codec->height = AV_RL16(&vmd->vmd_header[14]);
00119     if(vmd->is_indeo3 && vst->codec->width > 320){
00120         vst->codec->width >>= 1;
00121         vst->codec->height >>= 1;
00122     }
00123     vst->codec->extradata_size = VMD_HEADER_SIZE;
00124     vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
00125     memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
00126 
00127     /* if sample rate is 0, assume no audio */
00128     vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);
00129     if (vmd->sample_rate) {
00130         st = avformat_new_stream(s, NULL);
00131         if (!st)
00132             return AVERROR(ENOMEM);
00133         vmd->audio_stream_index = st->index;
00134         st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00135         st->codec->codec_id = CODEC_ID_VMDAUDIO;
00136         st->codec->codec_tag = 0;  /* no fourcc */
00137         st->codec->channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
00138         st->codec->sample_rate = vmd->sample_rate;
00139         st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);
00140         if (st->codec->block_align & 0x8000) {
00141             st->codec->bits_per_coded_sample = 16;
00142             st->codec->block_align = -(st->codec->block_align - 0x10000);
00143         } else {
00144             st->codec->bits_per_coded_sample = 8;
00145         }
00146         st->codec->bit_rate = st->codec->sample_rate *
00147             st->codec->bits_per_coded_sample * st->codec->channels;
00148 
00149         /* calculate pts */
00150         num = st->codec->block_align;
00151         den = st->codec->sample_rate * st->codec->channels;
00152         av_reduce(&den, &num, den, num, (1UL<<31)-1);
00153         avpriv_set_pts_info(vst, 33, num, den);
00154         avpriv_set_pts_info(st, 33, num, den);
00155     }
00156 
00157     toc_offset = AV_RL32(&vmd->vmd_header[812]);
00158     vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
00159     vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);
00160     avio_seek(pb, toc_offset, SEEK_SET);
00161 
00162     raw_frame_table = NULL;
00163     vmd->frame_table = NULL;
00164     sound_buffers = AV_RL16(&vmd->vmd_header[808]);
00165     raw_frame_table_size = vmd->frame_count * 6;
00166     if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){
00167         av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
00168         return -1;
00169     }
00170     raw_frame_table = av_malloc(raw_frame_table_size);
00171     vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame));
00172     if (!raw_frame_table || !vmd->frame_table) {
00173         av_free(raw_frame_table);
00174         av_free(vmd->frame_table);
00175         return AVERROR(ENOMEM);
00176     }
00177     if (avio_read(pb, raw_frame_table, raw_frame_table_size) !=
00178         raw_frame_table_size) {
00179         av_free(raw_frame_table);
00180         av_free(vmd->frame_table);
00181         return AVERROR(EIO);
00182     }
00183 
00184     total_frames = 0;
00185     for (i = 0; i < vmd->frame_count; i++) {
00186 
00187         current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);
00188 
00189         /* handle each entry in index block */
00190         for (j = 0; j < vmd->frames_per_block; j++) {
00191             int type;
00192             uint32_t size;
00193 
00194             avio_read(pb, chunk, BYTES_PER_FRAME_RECORD);
00195             type = chunk[0];
00196             size = AV_RL32(&chunk[2]);
00197             if(!size && type != 1)
00198                 continue;
00199             switch(type) {
00200             case 1: /* Audio Chunk */
00201                 if (!st) break;
00202                 /* first audio chunk contains several audio buffers */
00203                 vmd->frame_table[total_frames].frame_offset = current_offset;
00204                 vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
00205                 vmd->frame_table[total_frames].frame_size = size;
00206                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
00207                 vmd->frame_table[total_frames].pts = current_audio_pts;
00208                 total_frames++;
00209                 if(!current_audio_pts)
00210                     current_audio_pts += sound_buffers;
00211                 else
00212                     current_audio_pts++;
00213                 break;
00214             case 2: /* Video Chunk */
00215                 vmd->frame_table[total_frames].frame_offset = current_offset;
00216                 vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
00217                 vmd->frame_table[total_frames].frame_size = size;
00218                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
00219                 vmd->frame_table[total_frames].pts = i;
00220                 total_frames++;
00221                 break;
00222             }
00223             current_offset += size;
00224         }
00225     }
00226 
00227     av_free(raw_frame_table);
00228 
00229     vmd->current_frame = 0;
00230     vmd->frame_count = total_frames;
00231 
00232     return 0;
00233 }
00234 
00235 static int vmd_read_packet(AVFormatContext *s,
00236                            AVPacket *pkt)
00237 {
00238     VmdDemuxContext *vmd = s->priv_data;
00239     AVIOContext *pb = s->pb;
00240     int ret = 0;
00241     vmd_frame *frame;
00242 
00243     if (vmd->current_frame >= vmd->frame_count)
00244         return AVERROR(EIO);
00245 
00246     frame = &vmd->frame_table[vmd->current_frame];
00247     /* position the stream (will probably be there already) */
00248     avio_seek(pb, frame->frame_offset, SEEK_SET);
00249 
00250     if(ffio_limit(pb, frame->frame_size) != frame->frame_size)
00251         return AVERROR(EIO);
00252     if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD))
00253         return AVERROR(ENOMEM);
00254     pkt->pos= avio_tell(pb);
00255     memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
00256     if(vmd->is_indeo3 && frame->frame_record[0] == 0x02)
00257         ret = avio_read(pb, pkt->data, frame->frame_size);
00258     else
00259         ret = avio_read(pb, pkt->data + BYTES_PER_FRAME_RECORD,
00260             frame->frame_size);
00261 
00262     if (ret != frame->frame_size) {
00263         av_free_packet(pkt);
00264         ret = AVERROR(EIO);
00265     }
00266     pkt->stream_index = frame->stream_index;
00267     pkt->pts = frame->pts;
00268     av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
00269             (frame->frame_record[0] == 0x02) ? "video" : "audio",
00270             frame->frame_size + BYTES_PER_FRAME_RECORD,
00271             pkt->pts);
00272 
00273     vmd->current_frame++;
00274 
00275     return ret;
00276 }
00277 
00278 static int vmd_read_close(AVFormatContext *s)
00279 {
00280     VmdDemuxContext *vmd = s->priv_data;
00281 
00282     av_free(vmd->frame_table);
00283 
00284     return 0;
00285 }
00286 
00287 AVInputFormat ff_vmd_demuxer = {
00288     .name           = "vmd",
00289     .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD format"),
00290     .priv_data_size = sizeof(VmdDemuxContext),
00291     .read_probe     = vmd_probe,
00292     .read_header    = vmd_read_header,
00293     .read_packet    = vmd_read_packet,
00294     .read_close     = vmd_read_close,
00295 };