mmf.c
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1 /*
2  * Yamaha SMAF format
3  * Copyright (c) 2005 Vidar Madsen
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 #include "avformat.h"
22 #include "internal.h"
23 #include "avio_internal.h"
24 #include "pcm.h"
25 #include "riff.h"
26 
27 typedef struct {
28  int64_t atrpos, atsqpos, awapos;
29  int64_t data_size;
30 } MMFContext;
31 
32 static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
33 
34 static int mmf_rate(int code)
35 {
36  if((code < 0) || (code > 4))
37  return -1;
38  return mmf_rates[code];
39 }
40 
41 #if CONFIG_MMF_MUXER
42 static int mmf_rate_code(int rate)
43 {
44  int i;
45  for(i = 0; i < 5; i++)
46  if(mmf_rates[i] == rate)
47  return i;
48  return -1;
49 }
50 
51 /* Copy of end_tag() from avienc.c, but for big-endian chunk size */
52 static void end_tag_be(AVIOContext *pb, int64_t start)
53 {
54  int64_t pos;
55 
56  pos = avio_tell(pb);
57  avio_seek(pb, start - 4, SEEK_SET);
58  avio_wb32(pb, (uint32_t)(pos - start));
59  avio_seek(pb, pos, SEEK_SET);
60 }
61 
62 static int mmf_write_header(AVFormatContext *s)
63 {
64  MMFContext *mmf = s->priv_data;
65  AVIOContext *pb = s->pb;
66  int64_t pos;
67  int rate;
68 
69  rate = mmf_rate_code(s->streams[0]->codec->sample_rate);
70  if(rate < 0) {
71  av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d\n", s->streams[0]->codec->sample_rate);
72  return -1;
73  }
74 
75  ffio_wfourcc(pb, "MMMD");
76  avio_wb32(pb, 0);
77  pos = ff_start_tag(pb, "CNTI");
78  avio_w8(pb, 0); /* class */
79  avio_w8(pb, 0); /* type */
80  avio_w8(pb, 0); /* code type */
81  avio_w8(pb, 0); /* status */
82  avio_w8(pb, 0); /* counts */
83  avio_write(pb, "VN:libavcodec,", sizeof("VN:libavcodec,") -1); /* metadata ("ST:songtitle,VN:version,...") */
84  end_tag_be(pb, pos);
85 
86  avio_write(pb, "ATR\x00", 4);
87  avio_wb32(pb, 0);
88  mmf->atrpos = avio_tell(pb);
89  avio_w8(pb, 0); /* format type */
90  avio_w8(pb, 0); /* sequence type */
91  avio_w8(pb, (0 << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
92  avio_w8(pb, 0); /* wave base bit */
93  avio_w8(pb, 2); /* time base d */
94  avio_w8(pb, 2); /* time base g */
95 
96  ffio_wfourcc(pb, "Atsq");
97  avio_wb32(pb, 16);
98  mmf->atsqpos = avio_tell(pb);
99  /* Will be filled on close */
100  avio_write(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
101 
102  mmf->awapos = ff_start_tag(pb, "Awa\x01");
103 
104  avpriv_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
105 
106  avio_flush(pb);
107 
108  return 0;
109 }
110 
111 static int mmf_write_packet(AVFormatContext *s, AVPacket *pkt)
112 {
113  AVIOContext *pb = s->pb;
114  avio_write(pb, pkt->data, pkt->size);
115  return 0;
116 }
117 
118 /* Write a variable-length symbol */
119 static void put_varlength(AVIOContext *pb, int val)
120 {
121  if(val < 128)
122  avio_w8(pb, val);
123  else {
124  val -= 128;
125  avio_w8(pb, 0x80 | val >> 7);
126  avio_w8(pb, 0x7f & val);
127  }
128 }
129 
130 static int mmf_write_trailer(AVFormatContext *s)
131 {
132  AVIOContext *pb = s->pb;
133  MMFContext *mmf = s->priv_data;
134  int64_t pos, size;
135  int gatetime;
136 
137  if (s->pb->seekable) {
138  /* Fill in length fields */
139  end_tag_be(pb, mmf->awapos);
140  end_tag_be(pb, mmf->atrpos);
141  end_tag_be(pb, 8);
142 
143  pos = avio_tell(pb);
144  size = pos - mmf->awapos;
145 
146  /* Fill Atsq chunk */
147  avio_seek(pb, mmf->atsqpos, SEEK_SET);
148 
149  /* "play wav" */
150  avio_w8(pb, 0); /* start time */
151  avio_w8(pb, 1); /* (channel << 6) | wavenum */
152  gatetime = size * 500 / s->streams[0]->codec->sample_rate;
153  put_varlength(pb, gatetime); /* duration */
154 
155  /* "nop" */
156  put_varlength(pb, gatetime); /* start time */
157  avio_write(pb, "\xff\x00", 2); /* nop */
158 
159  /* "end of sequence" */
160  avio_write(pb, "\x00\x00\x00\x00", 4);
161 
162  avio_seek(pb, pos, SEEK_SET);
163 
164  avio_flush(pb);
165  }
166  return 0;
167 }
168 #endif /* CONFIG_MMF_MUXER */
169 
170 static int mmf_probe(AVProbeData *p)
171 {
172  /* check file header */
173  if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
174  p->buf[2] == 'M' && p->buf[3] == 'D' &&
175  p->buf[8] == 'C' && p->buf[9] == 'N' &&
176  p->buf[10] == 'T' && p->buf[11] == 'I')
177  return AVPROBE_SCORE_MAX;
178  else
179  return 0;
180 }
181 
182 /* mmf input */
184  AVFormatParameters *ap)
185 {
186  MMFContext *mmf = s->priv_data;
187  unsigned int tag;
188  AVIOContext *pb = s->pb;
189  AVStream *st;
190  int64_t size;
191  int rate, params;
192 
193  tag = avio_rl32(pb);
194  if (tag != MKTAG('M', 'M', 'M', 'D'))
195  return -1;
196  avio_skip(pb, 4); /* file_size */
197 
198  /* Skip some unused chunks that may or may not be present */
199  for(;; avio_skip(pb, size)) {
200  tag = avio_rl32(pb);
201  size = avio_rb32(pb);
202  if(tag == MKTAG('C','N','T','I')) continue;
203  if(tag == MKTAG('O','P','D','A')) continue;
204  break;
205  }
206 
207  /* Tag = "ATRx", where "x" = track number */
208  if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
209  av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
210  return -1;
211  }
212  if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
213  av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
214  return -1;
215  }
216 
217  avio_r8(pb); /* format type */
218  avio_r8(pb); /* sequence type */
219  params = avio_r8(pb); /* (channel << 7) | (format << 4) | rate */
220  rate = mmf_rate(params & 0x0f);
221  if(rate < 0) {
222  av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
223  return -1;
224  }
225  avio_r8(pb); /* wave base bit */
226  avio_r8(pb); /* time base d */
227  avio_r8(pb); /* time base g */
228 
229  /* Skip some unused chunks that may or may not be present */
230  for(;; avio_skip(pb, size)) {
231  tag = avio_rl32(pb);
232  size = avio_rb32(pb);
233  if(tag == MKTAG('A','t','s','q')) continue;
234  if(tag == MKTAG('A','s','p','I')) continue;
235  break;
236  }
237 
238  /* Make sure it's followed by an Awa chunk, aka wave data */
239  if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
240  av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
241  return -1;
242  }
243  mmf->data_size = size;
244 
245  st = avformat_new_stream(s, NULL);
246  if (!st)
247  return AVERROR(ENOMEM);
248 
251  st->codec->sample_rate = rate;
252  st->codec->channels = 1;
253  st->codec->bits_per_coded_sample = 4;
255 
256  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
257 
258  return 0;
259 }
260 
261 #define MAX_SIZE 4096
262 
264  AVPacket *pkt)
265 {
266  MMFContext *mmf = s->priv_data;
267  int ret, size;
268 
269  if (s->pb->eof_reached)
270  return AVERROR(EIO);
271 
272  size = MAX_SIZE;
273  if(size > mmf->data_size)
274  size = mmf->data_size;
275 
276  if(!size)
277  return AVERROR(EIO);
278 
279  if (av_new_packet(pkt, size))
280  return AVERROR(EIO);
281  pkt->stream_index = 0;
282 
283  ret = avio_read(s->pb, pkt->data, pkt->size);
284  if (ret < 0)
285  av_free_packet(pkt);
286 
287  mmf->data_size -= ret;
288 
289  pkt->size = ret;
290  return ret;
291 }
292 
293 #if CONFIG_MMF_DEMUXER
294 AVInputFormat ff_mmf_demuxer = {
295  .name = "mmf",
296  .long_name = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
297  .priv_data_size = sizeof(MMFContext),
302 };
303 #endif
304 #if CONFIG_MMF_MUXER
305 AVOutputFormat ff_mmf_muxer = {
306  .name = "mmf",
307  .long_name = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
308  .mime_type = "application/vnd.smaf",
309  .extensions = "mmf",
310  .priv_data_size = sizeof(MMFContext),
311  .audio_codec = CODEC_ID_ADPCM_YAMAHA,
312  .video_codec = CODEC_ID_NONE,
313  .write_header = mmf_write_header,
314  .write_packet = mmf_write_packet,
315  .write_trailer = mmf_write_trailer,
316 };
317 #endif