FFmpeg: libavformat/wvdec.c Source File

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libavformat

wvdec.c

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1 /*

2 * WavPack 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 "libavutil/channel_layout.h"

23 #include "libavutil/intreadwrite.h"

24 #include "libavutil/dict.h"

25 #include "avformat.h"

26 #include "internal.h"

27 #include "apetag.h"

28 #include "id3v1.h"

29 #include "wv.h"

31 enum WV_FLAGS {

32 WV_MONO = 0x0004,

33 WV_HYBRID = 0x0008,

34 WV_JOINT = 0x0010,

35 WV_CROSSD = 0x0020,

36 WV_HSHAPE = 0x0040,

37 WV_FLOAT = 0x0080,

38 WV_INT32 = 0x0100,

39 WV_HBR = 0x0200,

40 WV_HBAL = 0x0400,

41 WV_MCINIT = 0x0800,

42 WV_MCEND = 0x1000,

43 };

45 static const int wv_rates[16] = {

46 6000, 8000, 9600, 11025, 12000, 16000, 22050, 24000,

47 32000, 44100, 48000, 64000, 88200, 96000, 192000, -1

48 };

50 typedef struct WVContext {

51 uint8_t block_header[WV_HEADER_SIZE];

52 WvHeader header;

53 int rate, chan, bpp;

54 uint32_t chmask;

55 int multichannel;

56 int block_parsed;

57 int64_t pos;

59 int64_t apetag_start;

60 } WVContext;

62 static int wv_probe(AVProbeData *p)

63 {

64 /* check file header */

65 if (p->buf_size <= 32)

66 return 0;

67 if (AV_RL32(&p->buf[0]) == MKTAG('w', 'v', 'p', 'k') &&

68 AV_RL32(&p->buf[4]) >= 24 &&

69 AV_RL32(&p->buf[4]) <= WV_BLOCK_LIMIT &&

70 AV_RL16(&p->buf[8]) >= 0x402 &&

71 AV_RL16(&p->buf[8]) <= 0x410)

72 return AVPROBE_SCORE_MAX;

73 else

74 return 0;

75 }

77 static int wv_read_block_header(AVFormatContext *ctx, AVIOContext *pb)

78 {

79 WVContext *wc = ctx->priv_data;

80 int ret;

81 int rate, bpp, chan;

82 uint32_t chmask, flags;

84 wc->pos = avio_tell(pb);

86 /* don't return bogus packets with the ape tag data */

87 if (wc->apetag_start && wc->pos >= wc->apetag_start)

88 return AVERROR_EOF;

90 ret = avio_read(pb, wc->block_header, WV_HEADER_SIZE);

91 if (ret != WV_HEADER_SIZE)

92 return (ret < 0) ? ret : AVERROR_EOF;

94 ret = ff_wv_parse_header(&wc->header, wc->block_header);

95 if (ret < 0) {

96 av_log(ctx, AV_LOG_ERROR, "Invalid block header.\n");

97 return ret;

98 }

100 if (wc->header.version < 0x402 || wc->header.version > 0x410) {

101 av_log(ctx, AV_LOG_ERROR, "Unsupported version %03X\n", wc->header.version);

102 return AVERROR_PATCHWELCOME;

103 }

104

105 /* Blocks with zero samples don't contain actual audio information

106 * and should be ignored */

107 if (!wc->header.samples)

108 return 0;

109 // parse flags

110 flags = wc->header.flags;

111 bpp = ((flags & 3) + 1) << 3;

112 chan = 1 + !(flags & WV_MONO);

113 chmask = flags & WV_MONO ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;

114 rate = wv_rates[(flags >> 23) & 0xF];

115 wc->multichannel = !(wc->header.initial && wc->header.final);

116 if (wc->multichannel) {

117 chan = wc->chan;

118 chmask = wc->chmask;

119 }

120 if ((rate == -1 || !chan) && !wc->block_parsed) {

121 int64_t block_end = avio_tell(pb) + wc->header.blocksize;

122 if (!pb->seekable) {

123 av_log(ctx, AV_LOG_ERROR,

124 "Cannot determine additional parameters\n");

125 return AVERROR_INVALIDDATA;

126 }

127 while (avio_tell(pb) < block_end && !avio_feof(pb)) {

128 int id, size;

129 id = avio_r8(pb);

130 size = (id & 0x80) ? avio_rl24(pb) : avio_r8(pb);

131 size <<= 1;

132 if (id & 0x40)

133 size--;

134 switch (id & 0x3F) {

135 case 0xD:

136 if (size <= 1) {

137 av_log(ctx, AV_LOG_ERROR,

138 "Insufficient channel information\n");

139 return AVERROR_INVALIDDATA;

140 }

141 chan = avio_r8(pb);

142 switch (size - 2) {

143 case 0:

144 chmask = avio_r8(pb);

145 break;

146 case 1:

147 chmask = avio_rl16(pb);

148 break;

149 case 2:

150 chmask = avio_rl24(pb);

151 break;

152 case 3:

153 chmask = avio_rl32(pb);

154 break;

155 case 5:

156 avio_skip(pb, 1);

157 chan |= (avio_r8(pb) & 0xF) << 8;

158 chmask = avio_rl24(pb);

159 break;

160 default:

161 av_log(ctx, AV_LOG_ERROR,

162 "Invalid channel info size %d\n", size);

163 return AVERROR_INVALIDDATA;

164 }

165 break;

166 case 0x27:

167 rate = avio_rl24(pb);

168 break;

169 default:

170 avio_skip(pb, size);

171 }

172 if (id & 0x40)

173 avio_skip(pb, 1);

174 }

175 if (rate == -1) {

176 av_log(ctx, AV_LOG_ERROR,

177 "Cannot determine custom sampling rate\n");

178 return AVERROR_INVALIDDATA;

179 }

180 avio_seek(pb, block_end - wc->header.blocksize, SEEK_SET);

181 }

182 if (!wc->bpp)

183 wc->bpp = bpp;

184 if (!wc->chan)

185 wc->chan = chan;

186 if (!wc->chmask)

187 wc->chmask = chmask;

188 if (!wc->rate)

189 wc->rate = rate;

190

191 if (flags && bpp != wc->bpp) {

192 av_log(ctx, AV_LOG_ERROR,

193 "Bits per sample differ, this block: %i, header block: %i\n",

194 bpp, wc->bpp);

195 return AVERROR_INVALIDDATA;

196 }

197 if (flags && !wc->multichannel && chan != wc->chan) {

198 av_log(ctx, AV_LOG_ERROR,

199 "Channels differ, this block: %i, header block: %i\n",

200 chan, wc->chan);

201 return AVERROR_INVALIDDATA;

202 }

203 if (flags && rate != -1 && rate != wc->rate) {

204 av_log(ctx, AV_LOG_ERROR,

205 "Sampling rate differ, this block: %i, header block: %i\n",

206 rate, wc->rate);

207 return AVERROR_INVALIDDATA;

208 }

209 return 0;

210 }

211

212 static int wv_read_header(AVFormatContext *s)

213 {

214 AVIOContext *pb = s->pb;

215 WVContext *wc = s->priv_data;

216 AVStream *st;

217 int ret;

218

219 wc->block_parsed = 0;

220 for (;;) {

221 if ((ret = wv_read_block_header(s, pb)) < 0)

222 return ret;

223 if (!wc->header.samples)

224 avio_skip(pb, wc->header.blocksize);

225 else

226 break;

227 }

228

229 /* now we are ready: build format streams */

230 st = avformat_new_stream(s, NULL);

231 if (!st)

232 return AVERROR(ENOMEM);

233 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

234 st->codec->codec_id = AV_CODEC_ID_WAVPACK;

235 st->codec->channels = wc->chan;

236 st->codec->channel_layout = wc->chmask;

237 st->codec->sample_rate = wc->rate;

238 st->codec->bits_per_coded_sample = wc->bpp;

239 avpriv_set_pts_info(st, 64, 1, wc->rate);

240 st->start_time = 0;

241 if (wc->header.total_samples != 0xFFFFFFFFu)

242 st->duration = wc->header.total_samples;

243

244 if (s->pb->seekable) {

245 int64_t cur = avio_tell(s->pb);

246 wc->apetag_start = ff_ape_parse_tag(s);

247 if (!av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX))

248 ff_id3v1_read(s);

249 avio_seek(s->pb, cur, SEEK_SET);

250 }

251

252 return 0;

253 }

254

255 static int wv_read_packet(AVFormatContext *s, AVPacket *pkt)

256 {

257 WVContext *wc = s->priv_data;

258 int ret;

259 int off;

260 int64_t pos;

261 uint32_t block_samples;

262

263 if (avio_feof(s->pb))

264 return AVERROR_EOF;

265 if (wc->block_parsed) {

266 if ((ret = wv_read_block_header(s, s->pb)) < 0)

267 return ret;

268 }

269

270 pos = wc->pos;

271 if (av_new_packet(pkt, wc->header.blocksize + WV_HEADER_SIZE) < 0)

272 return AVERROR(ENOMEM);

273 memcpy(pkt->data, wc->block_header, WV_HEADER_SIZE);

274 ret = avio_read(s->pb, pkt->data + WV_HEADER_SIZE, wc->header.blocksize);

275 if (ret != wc->header.blocksize) {

276 av_free_packet(pkt);

277 return AVERROR(EIO);

278 }

279 while (!(wc->header.flags & WV_FLAG_FINAL_BLOCK)) {

280 if ((ret = wv_read_block_header(s, s->pb)) < 0) {

281 av_free_packet(pkt);

282 return ret;

283 }

284

285 off = pkt->size;

286 if ((ret = av_grow_packet(pkt, WV_HEADER_SIZE + wc->header.blocksize)) < 0) {

287 av_free_packet(pkt);

288 return ret;

289 }

290 memcpy(pkt->data + off, wc->block_header, WV_HEADER_SIZE);

291

292 ret = avio_read(s->pb, pkt->data + off + WV_HEADER_SIZE, wc->header.blocksize);

293 if (ret != wc->header.blocksize) {

294 av_free_packet(pkt);

295 return (ret < 0) ? ret : AVERROR_EOF;

296 }

297 }

298 pkt->stream_index = 0;

299 wc->block_parsed = 1;

300 pkt->pts = wc->header.block_idx;

301 block_samples = wc->header.samples;

302 if (block_samples > INT32_MAX)

303 av_log(s, AV_LOG_WARNING,

304 "Too many samples in block: %"PRIu32"\n", block_samples);

305 else

306 pkt->duration = block_samples;

307

308 av_add_index_entry(s->streams[0], pos, pkt->pts, 0, 0, AVINDEX_KEYFRAME);

309 return 0;

310 }

311

312 static int wv_read_seek(AVFormatContext *s, int stream_index,

313 int64_t timestamp, int flags)

314 {

315 AVStream *st = s->streams[stream_index];

316 WVContext *wc = s->priv_data;

317 AVPacket pkt1, *pkt = &pkt1;

318 int ret;

319 int index = av_index_search_timestamp(st, timestamp, flags);

320 int64_t pos, pts;

321

322 /* if found, seek there */

323 if (index >= 0 &&

324 timestamp <= st->index_entries[st->nb_index_entries - 1].timestamp) {

325 wc->block_parsed = 1;

326 avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET);

327 return 0;

328 }

329 /* if timestamp is out of bounds, return error */

330 if (timestamp < 0 || timestamp >= s->duration)

331 return AVERROR(EINVAL);

332

333 pos = avio_tell(s->pb);

334 do {

335 ret = av_read_frame(s, pkt);

336 if (ret < 0) {

337 avio_seek(s->pb, pos, SEEK_SET);

338 return ret;

339 }

340 pts = pkt->pts;

341 av_free_packet(pkt);

342 } while(pts < timestamp);

343 return 0;

344 }

345

346 AVInputFormat ff_wv_demuxer = {

347 .name = "wv",

348 .long_name = NULL_IF_CONFIG_SMALL("WavPack"),

349 .priv_data_size = sizeof(WVContext),

350 .read_probe = wv_probe,

351 .read_header = wv_read_header,

352 .read_packet = wv_read_packet,

353 .read_seek = wv_read_seek,

354 };

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