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 "internal.h"

25 #include "avio_internal.h"

26 #include "pcm.h"

27 #include "rawenc.h"

28 #include "riff.h"

30 typedef struct {

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->streams[0]->codec->flags & CODEC_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", s->streams[0]->codec->sample_rate);

79 return AVERROR(EINVAL);

80 }

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

83 if (mmf->stereo &&

84 s->streams[0]->codec->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) {

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

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

87 FF_COMPLIANCE_EXPERIMENTAL);

88 return AVERROR(EINVAL);

89 }

91 ffio_wfourcc(pb, "MMMD");

92 avio_wb32(pb, 0);

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

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

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

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

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

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

99 end_tag_be(pb, pos);

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

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

102 end_tag_be(pb, pos);

103

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

105 avio_wb32(pb, 0);

106 mmf->atrpos = avio_tell(pb);

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

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

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

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

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

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

113

114 ffio_wfourcc(pb, "Atsq");

115 avio_wb32(pb, 16);

116 mmf->atsqpos = avio_tell(pb);

117 /* Will be filled on close */

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

119

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

121

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

123

124 avio_flush(pb);

125

126 return 0;

127 }

128

129 /* Write a variable-length symbol */

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

131 {

132 if(val < 128)

133 avio_w8(pb, val);

134 else {

135 val -= 128;

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

137 avio_w8(pb, 0x7f & val);

138 }

139 }

140

141 static int mmf_write_trailer(AVFormatContext *s)

142 {

143 AVIOContext *pb = s->pb;

144 MMFContext *mmf = s->priv_data;

145 int64_t pos, size;

146 int gatetime;

147

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

149 /* Fill in length fields */

150 end_tag_be(pb, mmf->awapos);

151 end_tag_be(pb, mmf->atrpos);

152 end_tag_be(pb, 8);

153

154 pos = avio_tell(pb);

155 size = pos - mmf->awapos;

156

157 /* Fill Atsq chunk */

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

159

160 /* "play wav" */

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

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

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

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

165

166 /* "nop" */

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

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

169

170 /* "end of sequence" */

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

172

173 avio_seek(pb, pos, SEEK_SET);

174

175 avio_flush(pb);

176 }

177 return 0;

178 }

179 #endif /* CONFIG_MMF_MUXER */

180

181 static int mmf_probe(AVProbeData *p)

182 {

183 /* check file header */

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

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

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

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

188 return AVPROBE_SCORE_MAX;

189 else

190 return 0;

191 }

192

193 /* mmf input */

194 static int mmf_read_header(AVFormatContext *s)

195 {

196 MMFContext *mmf = s->priv_data;

197 unsigned int tag;

198 AVIOContext *pb = s->pb;

199 AVStream *st;

200 int64_t size;

201 int rate, params;

202

203 tag = avio_rl32(pb);

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

205 return AVERROR_INVALIDDATA;

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

207

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

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

210 tag = avio_rl32(pb);

211 size = avio_rb32(pb);

212 if(tag == MKTAG('C','N','T','I')) continue;

213 if(tag == MKTAG('O','P','D','A')) continue;

214 break;

215 }

216

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

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

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

220 return AVERROR_PATCHWELCOME;

221 }

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

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

224 return AVERROR_PATCHWELCOME;

225 }

226

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

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

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

230 rate = mmf_rate(params & 0x0f);

231 if(rate < 0) {

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

233 return AVERROR_INVALIDDATA;

234 }

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

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

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

238

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

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

241 tag = avio_rl32(pb);

242 size = avio_rb32(pb);

243 if(tag == MKTAG('A','t','s','q')) continue;

244 if(tag == MKTAG('A','s','p','I')) continue;

245 break;

246 }

247

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

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

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

251 return AVERROR_INVALIDDATA;

252 }

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

254

255 st = avformat_new_stream(s, NULL);

256 if (!st)

257 return AVERROR(ENOMEM);

258

259 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

260 st->codec->codec_id = AV_CODEC_ID_ADPCM_YAMAHA;

261 st->codec->sample_rate = rate;

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

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

264 st->codec->bits_per_coded_sample = 4;

265 st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample;

266

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

268

269 return 0;

270 }

271

272 #define MAX_SIZE 4096

273

274 static int mmf_read_packet(AVFormatContext *s,

275 AVPacket *pkt)

276 {

277 MMFContext *mmf = s->priv_data;

278 int64_t left, size;

279 int ret;

280

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

282 size = FFMIN(left, MAX_SIZE);

283 if (url_feof(s->pb) || size <= 0)

284 return AVERROR_EOF;

285

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

287 if (ret < 0)

288 return ret;

289

290 pkt->stream_index = 0;

291

292 return ret;

293 }

294

295 #if CONFIG_MMF_DEMUXER

296 AVInputFormat ff_mmf_demuxer = {

297 .name = "mmf",

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

299 .priv_data_size = sizeof(MMFContext),

300 .read_probe = mmf_probe,

301 .read_header = mmf_read_header,

302 .read_packet = mmf_read_packet,

303 .flags = AVFMT_GENERIC_INDEX,

304 };

305 #endif

306 #if CONFIG_MMF_MUXER

307 AVOutputFormat ff_mmf_muxer = {

308 .name = "mmf",

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

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

311 .extensions = "mmf",

312 .priv_data_size = sizeof(MMFContext),

313 .audio_codec = AV_CODEC_ID_ADPCM_YAMAHA,

314 .video_codec = AV_CODEC_ID_NONE,

315 .write_header = mmf_write_header,

316 .write_packet = ff_raw_write_packet,

317 .write_trailer = mmf_write_trailer,

318 };

319 #endif

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