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 
00033 #define VMD_HEADER_SIZE 0x0330
00034 #define BYTES_PER_FRAME_RECORD 16
00035 
00036 typedef struct {
00037   int stream_index;
00038   int64_t frame_offset;
00039   unsigned int frame_size;
00040   int64_t pts;
00041   int keyframe;
00042   unsigned char frame_record[BYTES_PER_FRAME_RECORD];
00043 } vmd_frame;
00044 
00045 typedef struct VmdDemuxContext {
00046     int video_stream_index;
00047     int audio_stream_index;
00048 
00049     unsigned int frame_count;
00050     unsigned int frames_per_block;
00051     vmd_frame *frame_table;
00052     unsigned int current_frame;
00053     int is_indeo3;
00054 
00055     int sample_rate;
00056     int64_t audio_sample_counter;
00057     int skiphdr;
00058 
00059     unsigned char vmd_header[VMD_HEADER_SIZE];
00060 } VmdDemuxContext;
00061 
00062 static int vmd_probe(AVProbeData *p)
00063 {
00064     int w, h;
00065     if (p->buf_size < 16)
00066         return 0;
00067     /* check if the first 2 bytes of the file contain the appropriate size
00068      * of a VMD header chunk */
00069     if (AV_RL16(&p->buf[0]) != VMD_HEADER_SIZE - 2)
00070         return 0;
00071     w = AV_RL16(&p->buf[12]);
00072     h = AV_RL16(&p->buf[14]);
00073     if (!w || w > 2048 || !h || h > 2048)
00074         return 0;
00075 
00076     /* only return half certainty since this check is a bit sketchy */
00077     return AVPROBE_SCORE_MAX / 2;
00078 }
00079 
00080 static int vmd_read_header(AVFormatContext *s,
00081                            AVFormatParameters *ap)
00082 {
00083     VmdDemuxContext *vmd = s->priv_data;
00084     ByteIOContext *pb = s->pb;
00085     AVStream *st = NULL, *vst;
00086     unsigned int toc_offset;
00087     unsigned char *raw_frame_table;
00088     int raw_frame_table_size;
00089     int64_t current_offset;
00090     int i, j;
00091     unsigned int total_frames;
00092     int64_t current_audio_pts = 0;
00093     unsigned char chunk[BYTES_PER_FRAME_RECORD];
00094     int num, den;
00095     int sound_buffers;
00096 
00097     /* fetch the main header, including the 2 header length bytes */
00098     url_fseek(pb, 0, SEEK_SET);
00099     if (get_buffer(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)
00100         return AVERROR(EIO);
00101 
00102     if(vmd->vmd_header[16] == 'i' && vmd->vmd_header[17] == 'v' && vmd->vmd_header[18] == '3')
00103         vmd->is_indeo3 = 1;
00104     else
00105         vmd->is_indeo3 = 0;
00106     /* start up the decoders */
00107     vst = av_new_stream(s, 0);
00108     if (!vst)
00109         return AVERROR(ENOMEM);
00110     av_set_pts_info(vst, 33, 1, 10);
00111     vmd->video_stream_index = vst->index;
00112     vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00113     vst->codec->codec_id = vmd->is_indeo3 ? CODEC_ID_INDEO3 : CODEC_ID_VMDVIDEO;
00114     vst->codec->codec_tag = 0;  /* no fourcc */
00115     vst->codec->width = AV_RL16(&vmd->vmd_header[12]);
00116     vst->codec->height = AV_RL16(&vmd->vmd_header[14]);
00117     if(vmd->is_indeo3 && vst->codec->width > 320){
00118         vst->codec->width >>= 1;
00119         vst->codec->height >>= 1;
00120     }
00121     vst->codec->extradata_size = VMD_HEADER_SIZE;
00122     vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
00123     memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
00124 
00125     /* if sample rate is 0, assume no audio */
00126     vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);
00127     if (vmd->sample_rate) {
00128         st = av_new_stream(s, 0);
00129         if (!st)
00130             return AVERROR(ENOMEM);
00131         vmd->audio_stream_index = st->index;
00132         st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00133         st->codec->codec_id = CODEC_ID_VMDAUDIO;
00134         st->codec->codec_tag = 0;  /* no fourcc */
00135         st->codec->channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
00136         st->codec->sample_rate = vmd->sample_rate;
00137         st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);
00138         if (st->codec->block_align & 0x8000) {
00139             st->codec->bits_per_coded_sample = 16;
00140             st->codec->block_align = -(st->codec->block_align - 0x10000);
00141         } else {
00142             st->codec->bits_per_coded_sample = 8;
00143         }
00144         st->codec->bit_rate = st->codec->sample_rate *
00145             st->codec->bits_per_coded_sample * st->codec->channels;
00146 
00147         /* calculate pts */
00148         num = st->codec->block_align;
00149         den = st->codec->sample_rate * st->codec->channels;
00150         av_reduce(&den, &num, den, num, (1UL<<31)-1);
00151         av_set_pts_info(vst, 33, num, den);
00152         av_set_pts_info(st, 33, num, den);
00153     }
00154 
00155     toc_offset = AV_RL32(&vmd->vmd_header[812]);
00156     vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
00157     vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);
00158     url_fseek(pb, toc_offset, SEEK_SET);
00159 
00160     raw_frame_table = NULL;
00161     vmd->frame_table = NULL;
00162     sound_buffers = AV_RL16(&vmd->vmd_header[808]);
00163     raw_frame_table_size = vmd->frame_count * 6;
00164     if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){
00165         av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
00166         return -1;
00167     }
00168     raw_frame_table = av_malloc(raw_frame_table_size);
00169     vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame));
00170     if (!raw_frame_table || !vmd->frame_table) {
00171         av_free(raw_frame_table);
00172         av_free(vmd->frame_table);
00173         return AVERROR(ENOMEM);
00174     }
00175     if (get_buffer(pb, raw_frame_table, raw_frame_table_size) !=
00176         raw_frame_table_size) {
00177         av_free(raw_frame_table);
00178         av_free(vmd->frame_table);
00179         return AVERROR(EIO);
00180     }
00181 
00182     total_frames = 0;
00183     for (i = 0; i < vmd->frame_count; i++) {
00184 
00185         current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);
00186 
00187         /* handle each entry in index block */
00188         for (j = 0; j < vmd->frames_per_block; j++) {
00189             int type;
00190             uint32_t size;
00191 
00192             get_buffer(pb, chunk, BYTES_PER_FRAME_RECORD);
00193             type = chunk[0];
00194             size = AV_RL32(&chunk[2]);
00195             if(!size && type != 1)
00196                 continue;
00197             switch(type) {
00198             case 1: /* Audio Chunk */
00199                 if (!st) break;
00200                 /* first audio chunk contains several audio buffers */
00201                 vmd->frame_table[total_frames].frame_offset = current_offset;
00202                 vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
00203                 vmd->frame_table[total_frames].frame_size = size;
00204                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
00205                 vmd->frame_table[total_frames].pts = current_audio_pts;
00206                 total_frames++;
00207                 if(!current_audio_pts)
00208                     current_audio_pts += sound_buffers;
00209                 else
00210                     current_audio_pts++;
00211                 break;
00212             case 2: /* Video Chunk */
00213                 vmd->frame_table[total_frames].frame_offset = current_offset;
00214                 vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
00215                 vmd->frame_table[total_frames].frame_size = size;
00216                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
00217                 vmd->frame_table[total_frames].pts = i;
00218                 total_frames++;
00219                 break;
00220             }
00221             current_offset += size;
00222         }
00223     }
00224 
00225     av_free(raw_frame_table);
00226 
00227     vmd->current_frame = 0;
00228     vmd->frame_count = total_frames;
00229 
00230     return 0;
00231 }
00232 
00233 static int vmd_read_packet(AVFormatContext *s,
00234                            AVPacket *pkt)
00235 {
00236     VmdDemuxContext *vmd = s->priv_data;
00237     ByteIOContext *pb = s->pb;
00238     int ret = 0;
00239     vmd_frame *frame;
00240 
00241     if (vmd->current_frame >= vmd->frame_count)
00242         return AVERROR(EIO);
00243 
00244     frame = &vmd->frame_table[vmd->current_frame];
00245     /* position the stream (will probably be there already) */
00246     url_fseek(pb, frame->frame_offset, SEEK_SET);
00247 
00248     if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD))
00249         return AVERROR(ENOMEM);
00250     pkt->pos= url_ftell(pb);
00251     memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
00252     if(vmd->is_indeo3)
00253         ret = get_buffer(pb, pkt->data, frame->frame_size);
00254     else
00255         ret = get_buffer(pb, pkt->data + BYTES_PER_FRAME_RECORD,
00256             frame->frame_size);
00257 
00258     if (ret != frame->frame_size) {
00259         av_free_packet(pkt);
00260         ret = AVERROR(EIO);
00261     }
00262     pkt->stream_index = frame->stream_index;
00263     pkt->pts = frame->pts;
00264     av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
00265             (frame->frame_record[0] == 0x02) ? "video" : "audio",
00266             frame->frame_size + BYTES_PER_FRAME_RECORD,
00267             pkt->pts);
00268 
00269     vmd->current_frame++;
00270 
00271     return ret;
00272 }
00273 
00274 static int vmd_read_close(AVFormatContext *s)
00275 {
00276     VmdDemuxContext *vmd = s->priv_data;
00277 
00278     av_free(vmd->frame_table);
00279 
00280     return 0;
00281 }
00282 
00283 AVInputFormat vmd_demuxer = {
00284     "vmd",
00285     NULL_IF_CONFIG_SMALL("Sierra VMD format"),
00286     sizeof(VmdDemuxContext),
00287     vmd_probe,
00288     vmd_read_header,
00289     vmd_read_packet,
00290     vmd_read_close,
00291 };