libavformat/oggparseogm.c
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00001 
00025 #include <stdlib.h>
00026 #include "libavutil/intreadwrite.h"
00027 #include "libavcodec/get_bits.h"
00028 #include "libavcodec/bytestream.h"
00029 #include "avformat.h"
00030 #include "internal.h"
00031 #include "oggdec.h"
00032 #include "riff.h"
00033 
00034 static int
00035 ogm_header(AVFormatContext *s, int idx)
00036 {
00037     struct ogg *ogg = s->priv_data;
00038     struct ogg_stream *os = ogg->streams + idx;
00039     AVStream *st = s->streams[idx];
00040     const uint8_t *p = os->buf + os->pstart;
00041     uint64_t time_unit;
00042     uint64_t spu;
00043 
00044     if(!(*p & 1))
00045         return 0;
00046 
00047     if(*p == 1) {
00048         p++;
00049 
00050         if(*p == 'v'){
00051             int tag;
00052             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00053             p += 8;
00054             tag = bytestream_get_le32(&p);
00055             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, tag);
00056             st->codec->codec_tag = tag;
00057         } else if (*p == 't') {
00058             st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
00059             st->codec->codec_id = CODEC_ID_TEXT;
00060             p += 12;
00061         } else {
00062             uint8_t acid[5];
00063             int cid;
00064             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00065             p += 8;
00066             bytestream_get_buffer(&p, acid, 4);
00067             acid[4] = 0;
00068             cid = strtol(acid, NULL, 16);
00069             st->codec->codec_id = ff_codec_get_id(ff_codec_wav_tags, cid);
00070             st->need_parsing = AVSTREAM_PARSE_FULL;
00071         }
00072 
00073         p += 4;                     /* useless size field */
00074 
00075         time_unit   = bytestream_get_le64(&p);
00076         spu         = bytestream_get_le64(&p);
00077         p += 4;                     /* default_len */
00078         p += 8;                     /* buffersize + bits_per_sample */
00079 
00080         if(st->codec->codec_type == AVMEDIA_TYPE_VIDEO){
00081             st->codec->width = bytestream_get_le32(&p);
00082             st->codec->height = bytestream_get_le32(&p);
00083             st->codec->time_base.den = spu * 10000000;
00084             st->codec->time_base.num = time_unit;
00085             avpriv_set_pts_info(st, 64, st->codec->time_base.num, st->codec->time_base.den);
00086         } else {
00087             st->codec->channels = bytestream_get_le16(&p);
00088             p += 2;                 /* block_align */
00089             st->codec->bit_rate = bytestream_get_le32(&p) * 8;
00090             st->codec->sample_rate = spu * 10000000 / time_unit;
00091             avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
00092         }
00093     } else if (*p == 3) {
00094         if (os->psize > 8)
00095             ff_vorbis_comment(s, &st->metadata, p+7, os->psize-8);
00096     }
00097 
00098     return 1;
00099 }
00100 
00101 static int
00102 ogm_dshow_header(AVFormatContext *s, int idx)
00103 {
00104     struct ogg *ogg = s->priv_data;
00105     struct ogg_stream *os = ogg->streams + idx;
00106     AVStream *st = s->streams[idx];
00107     uint8_t *p = os->buf + os->pstart;
00108     uint32_t t;
00109 
00110     if(!(*p & 1))
00111         return 0;
00112     if(*p != 1)
00113         return 1;
00114 
00115     t = AV_RL32(p + 96);
00116 
00117     if(t == 0x05589f80){
00118         st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00119         st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(p + 68));
00120         st->codec->time_base.den = 10000000;
00121         st->codec->time_base.num = AV_RL64(p + 164);
00122         st->codec->width = AV_RL32(p + 176);
00123         st->codec->height = AV_RL32(p + 180);
00124     } else if(t == 0x05589f81){
00125         st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00126         st->codec->codec_id = ff_codec_get_id(ff_codec_wav_tags, AV_RL16(p + 124));
00127         st->codec->channels = AV_RL16(p + 126);
00128         st->codec->sample_rate = AV_RL32(p + 128);
00129         st->codec->bit_rate = AV_RL32(p + 132) * 8;
00130     }
00131 
00132     return 1;
00133 }
00134 
00135 static int
00136 ogm_packet(AVFormatContext *s, int idx)
00137 {
00138     struct ogg *ogg = s->priv_data;
00139     struct ogg_stream *os = ogg->streams + idx;
00140     uint8_t *p = os->buf + os->pstart;
00141     int lb;
00142 
00143     if(*p & 8)
00144         os->pflags |= AV_PKT_FLAG_KEY;
00145 
00146     lb = ((*p & 2) << 1) | ((*p >> 6) & 3);
00147     os->pstart += lb + 1;
00148     os->psize -= lb + 1;
00149 
00150     while (lb--)
00151         os->pduration += p[lb+1] << (lb*8);
00152 
00153     return 0;
00154 }
00155 
00156 const struct ogg_codec ff_ogm_video_codec = {
00157     .magic = "\001video",
00158     .magicsize = 6,
00159     .header = ogm_header,
00160     .packet = ogm_packet,
00161     .granule_is_start = 1,
00162 };
00163 
00164 const struct ogg_codec ff_ogm_audio_codec = {
00165     .magic = "\001audio",
00166     .magicsize = 6,
00167     .header = ogm_header,
00168     .packet = ogm_packet,
00169     .granule_is_start = 1,
00170 };
00171 
00172 const struct ogg_codec ff_ogm_text_codec = {
00173     .magic = "\001text",
00174     .magicsize = 5,
00175     .header = ogm_header,
00176     .packet = ogm_packet,
00177     .granule_is_start = 1,
00178 };
00179 
00180 const struct ogg_codec ff_ogm_old_codec = {
00181     .magic = "\001Direct Show Samples embedded in Ogg",
00182     .magicsize = 35,
00183     .header = ogm_dshow_header,
00184     .packet = ogm_packet,
00185     .granule_is_start = 1,
00186 };