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cafenc.c
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1 /*
2  * Core Audio Format muxer
3  * Copyright (c) 2011 Carl Eugen Hoyos
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 
22 #include "avformat.h"
23 #include "caf.h"
24 #include "isom.h"
25 #include "avio_internal.h"
26 #include "libavutil/intfloat.h"
27 #include "libavutil/dict.h"
28 
29 typedef struct {
30  int64_t data;
34  int packets;
35 } CAFContext;
36 
37 static uint32_t codec_flags(enum AVCodecID codec_id) {
38  switch (codec_id) {
41  return 1; //< kCAFLinearPCMFormatFlagIsFloat
45  return 2; //< kCAFLinearPCMFormatFlagIsLittleEndian
48  return 3; //< kCAFLinearPCMFormatFlagIsFloat | kCAFLinearPCMFormatFlagIsLittleEndian
49  default:
50  return 0;
51  }
52 }
53 
54 static uint32_t samples_per_packet(enum AVCodecID codec_id, int channels, int block_align) {
55  switch (codec_id) {
56  case AV_CODEC_ID_PCM_S8:
69  return 1;
70  case AV_CODEC_ID_MACE3:
71  case AV_CODEC_ID_MACE6:
72  return 6;
74  return 64;
75  case AV_CODEC_ID_AMR_NB:
76  case AV_CODEC_ID_GSM:
77  case AV_CODEC_ID_ILBC:
78  case AV_CODEC_ID_QCELP:
79  return 160;
80  case AV_CODEC_ID_GSM_MS:
81  return 320;
82  case AV_CODEC_ID_MP1:
83  return 384;
84  case AV_CODEC_ID_MP2:
85  case AV_CODEC_ID_MP3:
86  return 1152;
87  case AV_CODEC_ID_AC3:
88  return 1536;
89  case AV_CODEC_ID_QDM2:
90  return 2048 * channels;
91  case AV_CODEC_ID_ALAC:
92  return 4096;
94  return (block_align - 4 * channels) * 8 / (4 * channels) + 1;
96  return (block_align - 7 * channels) * 2 / channels + 2;
97  default:
98  return 0;
99  }
100 }
101 
103 {
104  AVIOContext *pb = s->pb;
105  AVCodecContext *enc = s->streams[0]->codec;
106  CAFContext *caf = s->priv_data;
107  AVDictionaryEntry *t = NULL;
108  unsigned int codec_tag = ff_codec_get_tag(ff_codec_caf_tags, enc->codec_id);
109  int64_t chunk_size = 0;
110  int frame_size = enc->frame_size;
111 
112  if (s->nb_streams != 1) {
113  av_log(s, AV_LOG_ERROR, "CAF files have exactly one stream\n");
114  return AVERROR(EINVAL);
115  }
116 
117  switch (enc->codec_id) {
118  case AV_CODEC_ID_AAC:
119  av_log(s, AV_LOG_ERROR, "muxing codec currently unsupported\n");
120  return AVERROR_PATCHWELCOME;
121  }
122 
123  switch (enc->codec_id) {
124  case AV_CODEC_ID_PCM_S8:
135  codec_tag = MKTAG('l','p','c','m');
136  }
137 
138  if (!codec_tag) {
139  av_log(s, AV_LOG_ERROR, "unsupported codec\n");
140  return AVERROR_INVALIDDATA;
141  }
142 
143  if (!enc->block_align && !pb->seekable) {
144  av_log(s, AV_LOG_ERROR, "Muxing variable packet size not supported on non seekable output\n");
145  return AVERROR_INVALIDDATA;
146  }
147 
148  if (enc->codec_id != AV_CODEC_ID_MP3 || frame_size != 576)
149  frame_size = samples_per_packet(enc->codec_id, enc->channels, enc->block_align);
150 
151  ffio_wfourcc(pb, "caff"); //< mFileType
152  avio_wb16(pb, 1); //< mFileVersion
153  avio_wb16(pb, 0); //< mFileFlags
154 
155  ffio_wfourcc(pb, "desc"); //< Audio Description chunk
156  avio_wb64(pb, 32); //< mChunkSize
157  avio_wb64(pb, av_double2int(enc->sample_rate)); //< mSampleRate
158  avio_wl32(pb, codec_tag); //< mFormatID
159  avio_wb32(pb, codec_flags(enc->codec_id)); //< mFormatFlags
160  avio_wb32(pb, enc->block_align); //< mBytesPerPacket
161  avio_wb32(pb, frame_size); //< mFramesPerPacket
162  avio_wb32(pb, enc->channels); //< mChannelsPerFrame
163  avio_wb32(pb, av_get_bits_per_sample(enc->codec_id)); //< mBitsPerChannel
164 
165  if (enc->channel_layout) {
166  ffio_wfourcc(pb, "chan");
167  avio_wb64(pb, 12);
169  }
170 
171  if (enc->codec_id == AV_CODEC_ID_ALAC) {
172  ffio_wfourcc(pb, "kuki");
173  avio_wb64(pb, 12 + enc->extradata_size);
174  avio_write(pb, "\0\0\0\14frmaalac", 12);
175  avio_write(pb, enc->extradata, enc->extradata_size);
176  } else if (enc->codec_id == AV_CODEC_ID_AMR_NB) {
177  ffio_wfourcc(pb, "kuki");
178  avio_wb64(pb, 29);
179  avio_write(pb, "\0\0\0\14frmasamr", 12);
180  avio_wb32(pb, 0x11); /* size */
181  avio_write(pb, "samrFFMP", 8);
182  avio_w8(pb, 0); /* decoder version */
183 
184  avio_wb16(pb, 0x81FF); /* Mode set (all modes for AMR_NB) */
185  avio_w8(pb, 0x00); /* Mode change period (no restriction) */
186  avio_w8(pb, 0x01); /* Frames per sample */
187  } else if (enc->codec_id == AV_CODEC_ID_QDM2) {
188  ffio_wfourcc(pb, "kuki");
189  avio_wb64(pb, enc->extradata_size);
190  avio_write(pb, enc->extradata, enc->extradata_size);
191  }
192 
193  if (av_dict_count(s->metadata)) {
194  ffio_wfourcc(pb, "info"); //< Information chunk
195  while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
196  chunk_size += strlen(t->key) + strlen(t->value) + 2;
197  }
198  avio_wb64(pb, chunk_size + 4);
200  t = NULL;
201  while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
202  avio_put_str(pb, t->key);
203  avio_put_str(pb, t->value);
204  }
205  }
206 
207  ffio_wfourcc(pb, "data"); //< Audio Data chunk
208  caf->data = avio_tell(pb);
209  avio_wb64(pb, -1); //< mChunkSize
210  avio_wb32(pb, 0); //< mEditCount
211 
212  avio_flush(pb);
213  return 0;
214 }
215 
217 {
218  CAFContext *caf = s->priv_data;
219 
220  avio_write(s->pb, pkt->data, pkt->size);
221  if (!s->streams[0]->codec->block_align) {
222  void *pkt_sizes = caf->pkt_sizes;
223  int i, alloc_size = caf->size_entries_used + 5;
224  if (alloc_size < 0) {
225  caf->pkt_sizes = NULL;
226  } else {
227  caf->pkt_sizes = av_fast_realloc(caf->pkt_sizes,
228  &caf->size_buffer_size,
229  alloc_size);
230  }
231  if (!caf->pkt_sizes) {
232  av_free(pkt_sizes);
233  return AVERROR(ENOMEM);
234  }
235  for (i = 4; i > 0; i--) {
236  unsigned top = pkt->size >> i * 7;
237  if (top)
238  caf->pkt_sizes[caf->size_entries_used++] = 128 | top;
239  }
240  caf->pkt_sizes[caf->size_entries_used++] = pkt->size & 127;
241  caf->packets++;
242  }
243  return 0;
244 }
245 
247 {
248  CAFContext *caf = s->priv_data;
249  AVIOContext *pb = s->pb;
250  AVCodecContext *enc = s->streams[0]->codec;
251 
252  if (pb->seekable) {
253  int64_t file_size = avio_tell(pb);
254 
255  avio_seek(pb, caf->data, SEEK_SET);
256  avio_wb64(pb, file_size - caf->data - 8);
257  avio_seek(pb, file_size, SEEK_SET);
258  if (!enc->block_align) {
259  ffio_wfourcc(pb, "pakt");
260  avio_wb64(pb, caf->size_entries_used + 24);
261  avio_wb64(pb, caf->packets); ///< mNumberPackets
262  avio_wb64(pb, caf->packets * samples_per_packet(enc->codec_id, enc->channels, enc->block_align)); ///< mNumberValidFrames
263  avio_wb32(pb, 0); ///< mPrimingFrames
264  avio_wb32(pb, 0); ///< mRemainderFrames
265  avio_write(pb, caf->pkt_sizes, caf->size_entries_used);
266  caf->size_buffer_size = 0;
267  }
268  avio_flush(pb);
269  }
270  av_freep(&caf->pkt_sizes);
271  return 0;
272 }
273 
275  .name = "caf",
276  .long_name = NULL_IF_CONFIG_SMALL("Apple CAF (Core Audio Format)"),
277  .mime_type = "audio/x-caf",
278  .extensions = "caf",
279  .priv_data_size = sizeof(CAFContext),
280  .audio_codec = AV_CODEC_ID_PCM_S16BE,
281  .video_codec = AV_CODEC_ID_NONE,
285  .codec_tag = (const AVCodecTag* const []){ff_codec_caf_tags, 0},
286 };