FFmpeg: libavformat/mmf.c Source File

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libavformat

mmf.c

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1 /*

2 * Yamaha SMAF format

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 "avformat.h"

24 #include "avio_internal.h"

25 #include "internal.h"

26 #include "pcm.h"

27 #include "rawenc.h"

28 #include "riff.h"

30 typedef struct MMFContext {

31 int64_t atrpos, atsqpos, awapos;

32 int64_t data_end;

33 int stereo;

34 } MMFContext;

36 static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };

38 static int mmf_rate(int code)

39 {

40 if ((code < 0) || (code > 4))

41 return -1;

42 return mmf_rates[code];

43 }

45 #if CONFIG_MMF_MUXER

46 static int mmf_rate_code(int rate)

47 {

48 int i;

49 for (i = 0; i < 5; i++)

50 if (mmf_rates[i] == rate)

51 return i;

52 return -1;

53 }

55 /* Copy of end_tag() from avienc.c, but for big-endian chunk size */

56 static void end_tag_be(AVIOContext *pb, int64_t start)

57 {

58 int64_t pos;

60 pos = avio_tell(pb);

61 avio_seek(pb, start - 4, SEEK_SET);

62 avio_wb32(pb, (uint32_t)(pos - start));

63 avio_seek(pb, pos, SEEK_SET);

64 }

66 static int mmf_write_header(AVFormatContext *s)

67 {

68 MMFContext *mmf = s->priv_data;

69 AVIOContext *pb = s->pb;

70 int64_t pos;

71 int rate;

72 const char *version = s->flags & AVFMT_FLAG_BITEXACT ?

73 "VN:Lavf," :

74 "VN:"LIBAVFORMAT_IDENT ",";

76 rate = mmf_rate_code(s->streams[0]->codec->sample_rate);

77 if (rate < 0) {

78 av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d, supported are 4000, 8000, 11025, 22050 and 44100\n",

79 s->streams[0]->codec->sample_rate);

80 return AVERROR(EINVAL);

81 }

83 mmf->stereo = s->streams[0]->codec->channels > 1;

84 if (mmf->stereo &&

85 s->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) {

86 av_log(s, AV_LOG_ERROR, "Yamaha SMAF stereo is experimental, "

87 "add '-strict %d' if you want to use it.\n",

88 FF_COMPLIANCE_EXPERIMENTAL);

89 return AVERROR(EINVAL);

90 }

92 ffio_wfourcc(pb, "MMMD");

93 avio_wb32(pb, 0);

94 pos = ff_start_tag(pb, "CNTI");

95 avio_w8(pb, 0); /* class */

96 avio_w8(pb, 1); /* type */

97 avio_w8(pb, 1); /* code type */

98 avio_w8(pb, 0); /* status */

99 avio_w8(pb, 0); /* counts */

100 end_tag_be(pb, pos);

101

102 pos = ff_start_tag(pb, "OPDA");

103 avio_write(pb, version, strlen(version)); /* metadata ("ST:songtitle,VN:version,...") */

104 end_tag_be(pb, pos);

105

106 avio_write(pb, "ATR\x00", 4);

107 avio_wb32(pb, 0);

108 mmf->atrpos = avio_tell(pb);

109 avio_w8(pb, 0); /* format type */

110 avio_w8(pb, 0); /* sequence type */

111 avio_w8(pb, (mmf->stereo << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */

112 avio_w8(pb, 0); /* wave base bit */

113 avio_w8(pb, 2); /* time base d */

114 avio_w8(pb, 2); /* time base g */

115

116 ffio_wfourcc(pb, "Atsq");

117 avio_wb32(pb, 16);

118 mmf->atsqpos = avio_tell(pb);

119 /* Will be filled on close */

120 avio_write(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);

121

122 mmf->awapos = ff_start_tag(pb, "Awa\x01");

123

124 avpriv_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);

125

126 avio_flush(pb);

127

128 return 0;

129 }

130

131 /* Write a variable-length symbol */

132 static void put_varlength(AVIOContext *pb, int val)

133 {

134 if (val < 128)

135 avio_w8(pb, val);

136 else {

137 val -= 128;

138 avio_w8(pb, 0x80 | val >> 7);

139 avio_w8(pb, 0x7f & val);

140 }

141 }

142

143 static int mmf_write_trailer(AVFormatContext *s)

144 {

145 AVIOContext *pb = s->pb;

146 MMFContext *mmf = s->priv_data;

147 int64_t pos, size;

148 int gatetime;

149

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

151 /* Fill in length fields */

152 end_tag_be(pb, mmf->awapos);

153 end_tag_be(pb, mmf->atrpos);

154 end_tag_be(pb, 8);

155

156 pos = avio_tell(pb);

157 size = pos - mmf->awapos;

158

159 /* Fill Atsq chunk */

160 avio_seek(pb, mmf->atsqpos, SEEK_SET);

161

162 /* "play wav" */

163 avio_w8(pb, 0); /* start time */

164 avio_w8(pb, (mmf->stereo << 6) | 1); /* (channel << 6) | wavenum */

165 gatetime = size * 500 / s->streams[0]->codec->sample_rate;

166 put_varlength(pb, gatetime); /* duration */

167

168 /* "nop" */

169 put_varlength(pb, gatetime); /* start time */

170 avio_write(pb, "\xff\x00", 2); /* nop */

171

172 /* "end of sequence" */

173 avio_write(pb, "\x00\x00\x00\x00", 4);

174

175 avio_seek(pb, pos, SEEK_SET);

176

177 avio_flush(pb);

178 }

179 return 0;

180 }

181 #endif /* CONFIG_MMF_MUXER */

182

183 static int mmf_probe(AVProbeData *p)

184 {

185 /* check file header */

186 if (p->buf[0] == 'M' && p->buf[1] == 'M' &&

187 p->buf[2] == 'M' && p->buf[3] == 'D' &&

188 p->buf[8] == 'C' && p->buf[9] == 'N' &&

189 p->buf[10] == 'T' && p->buf[11] == 'I')

190 return AVPROBE_SCORE_MAX;

191 else

192 return 0;

193 }

194

195 /* mmf input */

196 static int mmf_read_header(AVFormatContext *s)

197 {

198 MMFContext *mmf = s->priv_data;

199 unsigned int tag;

200 AVIOContext *pb = s->pb;

201 AVStream *st;

202 int64_t size;

203 int rate, params;

204

205 tag = avio_rl32(pb);

206 if (tag != MKTAG('M', 'M', 'M', 'D'))

207 return AVERROR_INVALIDDATA;

208 avio_skip(pb, 4); /* file_size */

209

210 /* Skip some unused chunks that may or may not be present */

211 for (;; avio_skip(pb, size)) {

212 tag = avio_rl32(pb);

213 size = avio_rb32(pb);

214 if (tag == MKTAG('C', 'N', 'T', 'I'))

215 continue;

216 if (tag == MKTAG('O', 'P', 'D', 'A'))

217 continue;

218 break;

219 }

220

221 /* Tag = "ATRx", where "x" = track number */

222 if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {

223 av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");

224 return AVERROR_PATCHWELCOME;

225 }

226 if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {

227 av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);

228 return AVERROR_PATCHWELCOME;

229 }

230

231 avio_r8(pb); /* format type */

232 avio_r8(pb); /* sequence type */

233 params = avio_r8(pb); /* (channel << 7) | (format << 4) | rate */

234 rate = mmf_rate(params & 0x0f);

235 if (rate < 0) {

236 av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");

237 return AVERROR_INVALIDDATA;

238 }

239 avio_r8(pb); /* wave base bit */

240 avio_r8(pb); /* time base d */

241 avio_r8(pb); /* time base g */

242

243 /* Skip some unused chunks that may or may not be present */

244 for (;; avio_skip(pb, size)) {

245 tag = avio_rl32(pb);

246 size = avio_rb32(pb);

247 if (tag == MKTAG('A', 't', 's', 'q'))

248 continue;

249 if (tag == MKTAG('A', 's', 'p', 'I'))

250 continue;

251 break;

252 }

253

254 /* Make sure it's followed by an Awa chunk, aka wave data */

255 if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {

256 av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);

257 return AVERROR_INVALIDDATA;

258 }

259 mmf->data_end = avio_tell(pb) + size;

260

261 st = avformat_new_stream(s, NULL);

262 if (!st)

263 return AVERROR(ENOMEM);

264

265 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

266 st->codec->codec_id = AV_CODEC_ID_ADPCM_YAMAHA;

267 st->codec->sample_rate = rate;

268 st->codec->channels = (params >> 7) + 1;

269 st->codec->channel_layout = params >> 7 ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;

270 st->codec->bits_per_coded_sample = 4;

271 st->codec->bit_rate = st->codec->sample_rate *

272 st->codec->bits_per_coded_sample;

273

274 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);

275

276 return 0;

277 }

278

279 #define MAX_SIZE 4096

280

281 static int mmf_read_packet(AVFormatContext *s, AVPacket *pkt)

282 {

283 MMFContext *mmf = s->priv_data;

284 int64_t left, size;

285 int ret;

286

287 left = mmf->data_end - avio_tell(s->pb);

288 size = FFMIN(left, MAX_SIZE);

289 if (avio_feof(s->pb) || size <= 0)

290 return AVERROR_EOF;

291

292 ret = av_get_packet(s->pb, pkt, size);

293 if (ret < 0)

294 return ret;

295

296 pkt->stream_index = 0;

297

298 return ret;

299 }

300

301 #if CONFIG_MMF_DEMUXER

302 AVInputFormat ff_mmf_demuxer = {

303 .name = "mmf",

304 .long_name = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),

305 .priv_data_size = sizeof(MMFContext),

306 .read_probe = mmf_probe,

307 .read_header = mmf_read_header,

308 .read_packet = mmf_read_packet,

309 .flags = AVFMT_GENERIC_INDEX,

310 };

311 #endif

312

313 #if CONFIG_MMF_MUXER

314 AVOutputFormat ff_mmf_muxer = {

315 .name = "mmf",

316 .long_name = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),

317 .mime_type = "application/vnd.smaf",

318 .extensions = "mmf",

319 .priv_data_size = sizeof(MMFContext),

320 .audio_codec = AV_CODEC_ID_ADPCM_YAMAHA,

321 .video_codec = AV_CODEC_ID_NONE,

322 .write_header = mmf_write_header,

323 .write_packet = ff_raw_write_packet,

324 .write_trailer = mmf_write_trailer,

325 };

326 #endif

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