FFmpeg: libavformat/vqf.c Source File

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libavformat

vqf.c

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1 /*

2 * VQF demuxer

4 *

5 * This file is part of FFmpeg.

6 *

7 * FFmpeg is free software; you can redistribute it and/or

8 * modify it under the terms of the GNU Lesser General Public

9 * License as published by the Free Software Foundation; either

10 * version 2.1 of the License, or (at your option) any later version.

11 *

12 * FFmpeg is distributed in the hope that it will be useful,

13 * but WITHOUT ANY WARRANTY; without even the implied warranty of

14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

15 * Lesser General Public License for more details.

16 *

17 * You should have received a copy of the GNU Lesser General Public

18 * License along with FFmpeg; if not, write to the Free Software

19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

20 */

22 #include "avformat.h"

23 #include "internal.h"

24 #include "libavutil/intreadwrite.h"

25 #include "libavutil/dict.h"

26 #include "libavutil/mathematics.h"

27 #include "riff.h"

29 typedef struct VqfContext {

30 int frame_bit_len;

31 uint8_t last_frame_bits;

32 int remaining_bits;

33 } VqfContext;

35 static int vqf_probe(AVProbeData *probe_packet)

36 {

37 if (AV_RL32(probe_packet->buf) != MKTAG('T','W','I','N'))

38 return 0;

40 if (!memcmp(probe_packet->buf + 4, "97012000", 8))

41 return AVPROBE_SCORE_MAX;

43 if (!memcmp(probe_packet->buf + 4, "00052200", 8))

44 return AVPROBE_SCORE_MAX;

46 if (AV_RL32(probe_packet->buf + 12) > (1<<27))

47 return AVPROBE_SCORE_EXTENSION/2;

49 return AVPROBE_SCORE_EXTENSION;

50 }

52 static void add_metadata(AVFormatContext *s, uint32_t tag,

53 unsigned int tag_len, unsigned int remaining)

54 {

55 int len = FFMIN(tag_len, remaining);

56 char *buf, key[5] = {0};

58 if (len == UINT_MAX)

59 return;

61 buf = av_malloc(len+1);

62 if (!buf)

63 return;

64 avio_read(s->pb, buf, len);

65 buf[len] = 0;

66 AV_WL32(key, tag);

67 av_dict_set(&s->metadata, key, buf, AV_DICT_DONT_STRDUP_VAL);

68 }

70 static const AVMetadataConv vqf_metadata_conv[] = {

71 { "(c) ", "copyright" },

72 { "ARNG", "arranger" },

73 { "AUTH", "author" },

74 { "BAND", "band" },

75 { "CDCT", "conductor" },

76 { "COMT", "comment" },

77 { "FILE", "filename" },

78 { "GENR", "genre" },

79 { "LABL", "publisher" },

80 { "MUSC", "composer" },

81 { "NAME", "title" },

82 { "NOTE", "note" },

83 { "PROD", "producer" },

84 { "PRSN", "personnel" },

85 { "REMX", "remixer" },

86 { "SING", "singer" },

87 { "TRCK", "track" },

88 { "WORD", "words" },

89 { 0 },

90 };

92 static int vqf_read_header(AVFormatContext *s)

93 {

94 VqfContext *c = s->priv_data;

95 AVStream *st = avformat_new_stream(s, NULL);

96 int chunk_tag;

97 int rate_flag = -1;

98 int header_size;

99 int read_bitrate = 0;

100 int size;

101 uint8_t comm_chunk[12];

102

103 if (!st)

104 return AVERROR(ENOMEM);

105

106 avio_skip(s->pb, 12);

107

108 header_size = avio_rb32(s->pb);

109

110 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

111 st->codec->codec_id = AV_CODEC_ID_TWINVQ;

112 st->start_time = 0;

113

114 do {

115 int len;

116 chunk_tag = avio_rl32(s->pb);

117

118 if (chunk_tag == MKTAG('D','A','T','A'))

119 break;

120

121 len = avio_rb32(s->pb);

122

123 if ((unsigned) len > INT_MAX/2) {

124 av_log(s, AV_LOG_ERROR, "Malformed header\n");

125 return -1;

126 }

127

128 header_size -= 8;

129

130 switch(chunk_tag){

131 case MKTAG('C','O','M','M'):

132 avio_read(s->pb, comm_chunk, 12);

133 st->codec->channels = AV_RB32(comm_chunk ) + 1;

134 read_bitrate = AV_RB32(comm_chunk + 4);

135 rate_flag = AV_RB32(comm_chunk + 8);

136 avio_skip(s->pb, len-12);

137

138 if (st->codec->channels <= 0) {

139 av_log(s, AV_LOG_ERROR, "Invalid number of channels\n");

140 return AVERROR_INVALIDDATA;

141 }

142

143 st->codec->bit_rate = read_bitrate*1000;

144 break;

145 case MKTAG('D','S','I','Z'): // size of compressed data

146 {

147 av_dict_set_int(&s->metadata, "size", avio_rb32(s->pb), 0);

148 }

149 break;

150 case MKTAG('Y','E','A','R'): // recording date

151 case MKTAG('E','N','C','D'): // compression date

152 case MKTAG('E','X','T','R'): // reserved

153 case MKTAG('_','Y','M','H'): // reserved

154 case MKTAG('_','N','T','T'): // reserved

155 case MKTAG('_','I','D','3'): // reserved for ID3 tags

156 avio_skip(s->pb, FFMIN(len, header_size));

157 break;

158 default:

159 add_metadata(s, chunk_tag, len, header_size);

160 break;

161 }

162

163 header_size -= len;

164

165 } while (header_size >= 0 && !avio_feof(s->pb));

166

167 switch (rate_flag) {

168 case -1:

169 av_log(s, AV_LOG_ERROR, "COMM tag not found!\n");

170 return -1;

171 case 44:

172 st->codec->sample_rate = 44100;

173 break;

174 case 22:

175 st->codec->sample_rate = 22050;

176 break;

177 case 11:

178 st->codec->sample_rate = 11025;

179 break;

180 default:

181 if (rate_flag < 8 || rate_flag > 44) {

182 av_log(s, AV_LOG_ERROR, "Invalid rate flag %d\n", rate_flag);

183 return AVERROR_INVALIDDATA;

184 }

185 st->codec->sample_rate = rate_flag*1000;

186 break;

187 }

188

189 if (read_bitrate / st->codec->channels < 8 ||

190 read_bitrate / st->codec->channels > 48) {

191 av_log(s, AV_LOG_ERROR, "Invalid bitrate per channel %d\n",

192 read_bitrate / st->codec->channels);

193 return AVERROR_INVALIDDATA;

194 }

195

196 switch (((st->codec->sample_rate/1000) << 8) +

197 read_bitrate/st->codec->channels) {

198 case (11<<8) + 8 :

199 case (8 <<8) + 8 :

200 case (11<<8) + 10:

201 case (22<<8) + 32:

202 size = 512;

203 break;

204 case (16<<8) + 16:

205 case (22<<8) + 20:

206 case (22<<8) + 24:

207 size = 1024;

208 break;

209 case (44<<8) + 40:

210 case (44<<8) + 48:

211 size = 2048;

212 break;

213 default:

214 av_log(s, AV_LOG_ERROR, "Mode not suported: %d Hz, %d kb/s.\n",

215 st->codec->sample_rate, st->codec->bit_rate);

216 return -1;

217 }

218 c->frame_bit_len = st->codec->bit_rate*size/st->codec->sample_rate;

219 avpriv_set_pts_info(st, 64, size, st->codec->sample_rate);

220

221 /* put first 12 bytes of COMM chunk in extradata */

222 if (ff_alloc_extradata(st->codec, 12))

223 return AVERROR(ENOMEM);

224 memcpy(st->codec->extradata, comm_chunk, 12);

225

226 ff_metadata_conv_ctx(s, NULL, vqf_metadata_conv);

227

228 return 0;

229 }

230

231 static int vqf_read_packet(AVFormatContext *s, AVPacket *pkt)

232 {

233 VqfContext *c = s->priv_data;

234 int ret;

235 int size = (c->frame_bit_len - c->remaining_bits + 7)>>3;

236

237 if (av_new_packet(pkt, size+2) < 0)

238 return AVERROR(EIO);

239

240 pkt->pos = avio_tell(s->pb);

241 pkt->stream_index = 0;

242 pkt->duration = 1;

243

244 pkt->data[0] = 8 - c->remaining_bits; // Number of bits to skip

245 pkt->data[1] = c->last_frame_bits;

246 ret = avio_read(s->pb, pkt->data+2, size);

247

248 if (ret != size) {

249 av_free_packet(pkt);

250 return AVERROR(EIO);

251 }

252

253 c->last_frame_bits = pkt->data[size+1];

254 c->remaining_bits = (size << 3) - c->frame_bit_len + c->remaining_bits;

255

256 return size+2;

257 }

258

259 static int vqf_read_seek(AVFormatContext *s,

260 int stream_index, int64_t timestamp, int flags)

261 {

262 VqfContext *c = s->priv_data;

263 AVStream *st;

264 int64_t ret;

265 int64_t pos;

266

267 st = s->streams[stream_index];

268 pos = av_rescale_rnd(timestamp * st->codec->bit_rate,

269 st->time_base.num,

270 st->time_base.den * (int64_t)c->frame_bit_len,

271 (flags & AVSEEK_FLAG_BACKWARD) ?

272 AV_ROUND_DOWN : AV_ROUND_UP);

273 pos *= c->frame_bit_len;

274

275 st->cur_dts = av_rescale(pos, st->time_base.den,

276 st->codec->bit_rate * (int64_t)st->time_base.num);

277

278 if ((ret = avio_seek(s->pb, ((pos-7) >> 3) + s->internal->data_offset, SEEK_SET)) < 0)

279 return ret;

280

281 c->remaining_bits = -7 - ((pos-7)&7);

282 return 0;

283 }

284

285 AVInputFormat ff_vqf_demuxer = {

286 .name = "vqf",

287 .long_name = NULL_IF_CONFIG_SMALL("Nippon Telegraph and Telephone Corporation (NTT) TwinVQ"),

288 .priv_data_size = sizeof(VqfContext),

289 .read_probe = vqf_probe,

290 .read_header = vqf_read_header,

291 .read_packet = vqf_read_packet,

292 .read_seek = vqf_read_seek,

293 .extensions = "vqf,vql,vqe",

294 };

Generated on Sun Mar 8 2015 02:35:13 for FFmpeg by doxygen 1.8.2