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00031 #include "avformat.h"
00032 #include "internal.h"
00033
00034 typedef struct {
00035 unsigned int channels;
00036 unsigned int audio_pts;
00037 } CdataDemuxContext;
00038
00039 static int cdata_probe(AVProbeData *p)
00040 {
00041 const uint8_t *b = p->buf;
00042
00043 if (b[0] == 0x04 && (b[1] == 0x00 || b[1] == 0x04 || b[1] == 0x0C))
00044 return AVPROBE_SCORE_MAX/8;
00045 return 0;
00046 }
00047
00048 static int cdata_read_header(AVFormatContext *s, AVFormatParameters *ap)
00049 {
00050 CdataDemuxContext *cdata = s->priv_data;
00051 AVIOContext *pb = s->pb;
00052 unsigned int sample_rate, header;
00053 AVStream *st;
00054
00055 header = avio_rb16(pb);
00056 switch (header) {
00057 case 0x0400: cdata->channels = 1; break;
00058 case 0x0404: cdata->channels = 2; break;
00059 case 0x040C: cdata->channels = 4; break;
00060 default:
00061 av_log(s, AV_LOG_INFO, "unknown header 0x%04x\n", header);
00062 return -1;
00063 };
00064
00065 sample_rate = avio_rb16(pb);
00066 avio_skip(pb, 12);
00067
00068 st = avformat_new_stream(s, NULL);
00069 if (!st)
00070 return AVERROR(ENOMEM);
00071 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00072 st->codec->codec_tag = 0;
00073 st->codec->codec_id = CODEC_ID_ADPCM_EA_XAS;
00074 st->codec->channels = cdata->channels;
00075 st->codec->sample_rate = sample_rate;
00076 avpriv_set_pts_info(st, 64, 1, sample_rate);
00077
00078 cdata->audio_pts = 0;
00079 return 0;
00080 }
00081
00082 static int cdata_read_packet(AVFormatContext *s, AVPacket *pkt)
00083 {
00084 CdataDemuxContext *cdata = s->priv_data;
00085 int packet_size = 76*cdata->channels;
00086
00087 int ret = av_get_packet(s->pb, pkt, packet_size);
00088 if (ret < 0)
00089 return ret;
00090 pkt->pts = cdata->audio_pts++;
00091 return 0;
00092 }
00093
00094 AVInputFormat ff_ea_cdata_demuxer = {
00095 .name = "ea_cdata",
00096 .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts cdata"),
00097 .priv_data_size = sizeof(CdataDemuxContext),
00098 .read_probe = cdata_probe,
00099 .read_header = cdata_read_header,
00100 .read_packet = cdata_read_packet,
00101 .extensions = "cdata",
00102 };