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 {
00084     VmdDemuxContext *vmd = s->priv_data;
00085     AVIOContext *pb = s->pb;
00086     AVStream *st = NULL, *vst;
00087     unsigned int toc_offset;
00088     unsigned char *raw_frame_table;
00089     int raw_frame_table_size;
00090     int64_t current_offset;
00091     int i, j;
00092     unsigned int total_frames;
00093     int64_t current_audio_pts = 0;
00094     unsigned char chunk[BYTES_PER_FRAME_RECORD];
00095     int num, den;
00096     int sound_buffers;
00097 
00098     /* fetch the main header, including the 2 header length bytes */
00099     avio_seek(pb, 0, SEEK_SET);
00100     if (avio_read(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)
00101         return AVERROR(EIO);
00102 
00103     if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3')
00104         vmd->is_indeo3 = 1;
00105     else
00106         vmd->is_indeo3 = 0;
00107     /* start up the decoders */
00108     vst = avformat_new_stream(s, NULL);
00109     if (!vst)
00110         return AVERROR(ENOMEM);
00111     avpriv_set_pts_info(vst, 33, 1, 10);
00112     vmd->video_stream_index = vst->index;
00113     vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00114     vst->codec->codec_id = vmd->is_indeo3 ? AV_CODEC_ID_INDEO3 : AV_CODEC_ID_VMDVIDEO;
00115     vst->codec->codec_tag = 0;  /* no fourcc */
00116     vst->codec->width = AV_RL16(&vmd->vmd_header[12]);
00117     vst->codec->height = AV_RL16(&vmd->vmd_header[14]);
00118     if(vmd->is_indeo3 && vst->codec->width > 320){
00119         vst->codec->width >>= 1;
00120         vst->codec->height >>= 1;
00121     }
00122     vst->codec->extradata_size = VMD_HEADER_SIZE;
00123     vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
00124     memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
00125 
00126     /* if sample rate is 0, assume no audio */
00127     vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);
00128     if (vmd->sample_rate) {
00129         st = avformat_new_stream(s, NULL);
00130         if (!st)
00131             return AVERROR(ENOMEM);
00132         vmd->audio_stream_index = st->index;
00133         st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00134         st->codec->codec_id = AV_CODEC_ID_VMDAUDIO;
00135         st->codec->codec_tag = 0;  /* no fourcc */
00136         st->codec->channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
00137         st->codec->sample_rate = vmd->sample_rate;
00138         st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);
00139         if (st->codec->block_align & 0x8000) {
00140             st->codec->bits_per_coded_sample = 16;
00141             st->codec->block_align = -(st->codec->block_align - 0x10000);
00142         } else {
00143             st->codec->bits_per_coded_sample = 8;
00144         }
00145         st->codec->bit_rate = st->codec->sample_rate *
00146             st->codec->bits_per_coded_sample * st->codec->channels;
00147 
00148         /* calculate pts */
00149         num = st->codec->block_align;
00150         den = st->codec->sample_rate * st->codec->channels;
00151         av_reduce(&den, &num, den, num, (1UL<<31)-1);
00152         avpriv_set_pts_info(vst, 33, num, den);
00153         avpriv_set_pts_info(st, 33, num, den);
00154     }
00155 
00156     toc_offset = AV_RL32(&vmd->vmd_header[812]);
00157     vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
00158     vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);
00159     avio_seek(pb, toc_offset, SEEK_SET);
00160 
00161     raw_frame_table = NULL;
00162     vmd->frame_table = NULL;
00163     sound_buffers = AV_RL16(&vmd->vmd_header[808]);
00164     raw_frame_table_size = vmd->frame_count * 6;
00165     if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){
00166         av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
00167         return -1;
00168     }
00169     raw_frame_table = av_malloc(raw_frame_table_size);
00170     vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame));
00171     if (!raw_frame_table || !vmd->frame_table) {
00172         av_free(raw_frame_table);
00173         av_free(vmd->frame_table);
00174         return AVERROR(ENOMEM);
00175     }
00176     if (avio_read(pb, raw_frame_table, raw_frame_table_size) !=
00177         raw_frame_table_size) {
00178         av_free(raw_frame_table);
00179         av_free(vmd->frame_table);
00180         return AVERROR(EIO);
00181     }
00182 
00183     total_frames = 0;
00184     for (i = 0; i < vmd->frame_count; i++) {
00185 
00186         current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);
00187 
00188         /* handle each entry in index block */
00189         for (j = 0; j < vmd->frames_per_block; j++) {
00190             int type;
00191             uint32_t size;
00192 
00193             avio_read(pb, chunk, BYTES_PER_FRAME_RECORD);
00194             type = chunk[0];
00195             size = AV_RL32(&chunk[2]);
00196             if(!size && type != 1)
00197                 continue;
00198             switch(type) {
00199             case 1: /* Audio Chunk */
00200                 if (!st) break;
00201                 /* first audio chunk contains several audio buffers */
00202                 vmd->frame_table[total_frames].frame_offset = current_offset;
00203                 vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
00204                 vmd->frame_table[total_frames].frame_size = size;
00205                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
00206                 vmd->frame_table[total_frames].pts = current_audio_pts;
00207                 total_frames++;
00208                 if(!current_audio_pts)
00209                     current_audio_pts += sound_buffers - 1;
00210                 else
00211                     current_audio_pts++;
00212                 break;
00213             case 2: /* Video Chunk */
00214                 vmd->frame_table[total_frames].frame_offset = current_offset;
00215                 vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
00216                 vmd->frame_table[total_frames].frame_size = size;
00217                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
00218                 vmd->frame_table[total_frames].pts = i;
00219                 total_frames++;
00220                 break;
00221             }
00222             current_offset += size;
00223         }
00224     }
00225 
00226     av_free(raw_frame_table);
00227 
00228     vmd->current_frame = 0;
00229     vmd->frame_count = total_frames;
00230 
00231     return 0;
00232 }
00233 
00234 static int vmd_read_packet(AVFormatContext *s,
00235                            AVPacket *pkt)
00236 {
00237     VmdDemuxContext *vmd = s->priv_data;
00238     AVIOContext *pb = s->pb;
00239     int ret = 0;
00240     vmd_frame *frame;
00241 
00242     if (vmd->current_frame >= vmd->frame_count)
00243         return AVERROR(EIO);
00244 
00245     frame = &vmd->frame_table[vmd->current_frame];
00246     /* position the stream (will probably be there already) */
00247     avio_seek(pb, frame->frame_offset, SEEK_SET);
00248 
00249     if(ffio_limit(pb, frame->frame_size) != frame->frame_size)
00250         return AVERROR(EIO);
00251     if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD))
00252         return AVERROR(ENOMEM);
00253     pkt->pos= avio_tell(pb);
00254     memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
00255     if(vmd->is_indeo3 && frame->frame_record[0] == 0x02)
00256         ret = avio_read(pb, pkt->data, frame->frame_size);
00257     else
00258         ret = avio_read(pb, pkt->data + BYTES_PER_FRAME_RECORD,
00259             frame->frame_size);
00260 
00261     if (ret != frame->frame_size) {
00262         av_free_packet(pkt);
00263         ret = AVERROR(EIO);
00264     }
00265     pkt->stream_index = frame->stream_index;
00266     pkt->pts = frame->pts;
00267     av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
00268             (frame->frame_record[0] == 0x02) ? "video" : "audio",
00269             frame->frame_size + BYTES_PER_FRAME_RECORD,
00270             pkt->pts);
00271 
00272     vmd->current_frame++;
00273 
00274     return ret;
00275 }
00276 
00277 static int vmd_read_close(AVFormatContext *s)
00278 {
00279     VmdDemuxContext *vmd = s->priv_data;
00280 
00281     av_free(vmd->frame_table);
00282 
00283     return 0;
00284 }
00285 
00286 AVInputFormat ff_vmd_demuxer = {
00287     .name           = "vmd",
00288     .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD"),
00289     .priv_data_size = sizeof(VmdDemuxContext),
00290     .read_probe     = vmd_probe,
00291     .read_header    = vmd_read_header,
00292     .read_packet    = vmd_read_packet,
00293     .read_close     = vmd_read_close,
00294 };