00001
00002
00003
00004
00005
00006
00007
00008
00009
00010
00011
00012
00013
00014
00015
00016
00017
00018
00019
00020
00021
00022 #include "libavcodec/bitstream.h"
00023 #include "avformat.h"
00024
00025 typedef struct {
00026 int totalframes, currentframe;
00027 } TTAContext;
00028
00029 static int tta_probe(AVProbeData *p)
00030 {
00031 const uint8_t *d = p->buf;
00032 if (d[0] == 'T' && d[1] == 'T' && d[2] == 'A' && d[3] == '1')
00033 return 80;
00034 return 0;
00035 }
00036
00037 static int tta_read_header(AVFormatContext *s, AVFormatParameters *ap)
00038 {
00039 TTAContext *c = s->priv_data;
00040 AVStream *st;
00041 int i, channels, bps, samplerate, datalen, framelen;
00042 uint64_t framepos;
00043
00044 if (get_le32(s->pb) != AV_RL32("TTA1"))
00045 return -1;
00046
00047 url_fskip(s->pb, 2);
00048 channels = get_le16(s->pb);
00049 bps = get_le16(s->pb);
00050 samplerate = get_le32(s->pb);
00051 if(samplerate <= 0 || samplerate > 1000000){
00052 av_log(s, AV_LOG_ERROR, "nonsense samplerate\n");
00053 return -1;
00054 }
00055
00056 datalen = get_le32(s->pb);
00057 if(datalen < 0){
00058 av_log(s, AV_LOG_ERROR, "nonsense datalen\n");
00059 return -1;
00060 }
00061
00062 url_fskip(s->pb, 4);
00063
00064 framelen = samplerate*256/245;
00065 c->totalframes = datalen / framelen + ((datalen % framelen) ? 1 : 0);
00066 c->currentframe = 0;
00067
00068 if(c->totalframes >= UINT_MAX/sizeof(uint32_t)){
00069 av_log(s, AV_LOG_ERROR, "totalframes too large\n");
00070 return -1;
00071 }
00072
00073 st = av_new_stream(s, 0);
00074 if (!st)
00075 return AVERROR(ENOMEM);
00076
00077 av_set_pts_info(st, 64, 1, samplerate);
00078 st->start_time = 0;
00079 st->duration = datalen;
00080
00081 framepos = url_ftell(s->pb) + 4*c->totalframes + 4;
00082
00083 for (i = 0; i < c->totalframes; i++) {
00084 uint32_t size = get_le32(s->pb);
00085 av_add_index_entry(st, framepos, i*framelen, size, 0, AVINDEX_KEYFRAME);
00086 framepos += size;
00087 }
00088 url_fskip(s->pb, 4);
00089
00090 st->codec->codec_type = CODEC_TYPE_AUDIO;
00091 st->codec->codec_id = CODEC_ID_TTA;
00092 st->codec->channels = channels;
00093 st->codec->sample_rate = samplerate;
00094 st->codec->bits_per_coded_sample = bps;
00095
00096 st->codec->extradata_size = url_ftell(s->pb);
00097 if(st->codec->extradata_size+FF_INPUT_BUFFER_PADDING_SIZE <= (unsigned)st->codec->extradata_size){
00098
00099 av_log(s, AV_LOG_ERROR, "extradata_size too large\n");
00100 return -1;
00101 }
00102 st->codec->extradata = av_mallocz(st->codec->extradata_size+FF_INPUT_BUFFER_PADDING_SIZE);
00103 url_fseek(s->pb, 0, SEEK_SET);
00104 get_buffer(s->pb, st->codec->extradata, st->codec->extradata_size);
00105
00106 return 0;
00107 }
00108
00109 static int tta_read_packet(AVFormatContext *s, AVPacket *pkt)
00110 {
00111 TTAContext *c = s->priv_data;
00112 AVStream *st = s->streams[0];
00113 int size, ret;
00114
00115
00116 if (c->currentframe > c->totalframes)
00117 return -1;
00118
00119 size = st->index_entries[c->currentframe].size;
00120
00121 ret = av_get_packet(s->pb, pkt, size);
00122 pkt->dts = st->index_entries[c->currentframe++].timestamp;
00123 return ret;
00124 }
00125
00126 static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
00127 {
00128 TTAContext *c = s->priv_data;
00129 AVStream *st = s->streams[stream_index];
00130 int index = av_index_search_timestamp(st, timestamp, flags);
00131 if (index < 0)
00132 return -1;
00133
00134 c->currentframe = index;
00135 url_fseek(s->pb, st->index_entries[index].pos, SEEK_SET);
00136
00137 return 0;
00138 }
00139
00140 AVInputFormat tta_demuxer = {
00141 "tta",
00142 NULL_IF_CONFIG_SMALL("True Audio"),
00143 sizeof(TTAContext),
00144 tta_probe,
00145 tta_read_header,
00146 tta_read_packet,
00147 NULL,
00148 tta_read_seek,
00149 .extensions = "tta",
00150 };