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mmf.c
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1 /*
2  * Yamaha SMAF format
3  * Copyright (c) 2005 Vidar Madsen
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  */
21 
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"
29 
30 typedef struct {
31  int64_t atrpos, atsqpos, awapos;
32  int64_t data_end;
33  int stereo;
34 } MMFContext;
35 
36 static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
37 
38 static int mmf_rate(int code)
39 {
40  if ((code < 0) || (code > 4))
41  return -1;
42  return mmf_rates[code];
43 }
44 
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 }
54 
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;
59 
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 }
65 
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",";
75 
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  }
82 
83  mmf->stereo = s->streams[0]->codec->channels > 1;
84  if (mmf->stereo &&
86  av_log(s, AV_LOG_ERROR, "Yamaha SMAF stereo is experimental, "
87  "add '-strict %d' if you want to use it.\n",
89  return AVERROR(EINVAL);
90  }
91 
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 */
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 
267  st->codec->sample_rate = rate;
268  st->codec->channels = (params >> 7) + 1;
270  st->codec->bits_per_coded_sample = 4;
271  st->codec->bit_rate = st->codec->sample_rate *
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 
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 (url_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),
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,
324  .write_trailer = mmf_write_trailer,
325 };
326 #endif