FFmpeg: libavformat/cafenc.c Source File

FFmpeg
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;
31   uint8_t *pkt_sizes;
32   int size_buffer_size;
33   int size_entries_used;
34   int packets;
35 } CAFContext;
36 
37  static uint32_t codec_flags(enum AVCodecID codec_id) {
38  switch (codec_id) {
39  case AV_CODEC_ID_PCM_F32BE:
40  case AV_CODEC_ID_PCM_F64BE:
41  return 1; //< kCAFLinearPCMFormatFlagIsFloat
42  case AV_CODEC_ID_PCM_S16LE:
43  case AV_CODEC_ID_PCM_S24LE:
44  case AV_CODEC_ID_PCM_S32LE:
45  return 2; //< kCAFLinearPCMFormatFlagIsLittleEndian
46  case AV_CODEC_ID_PCM_F32LE:
47  case AV_CODEC_ID_PCM_F64LE:
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) {
55  switch (codec_id) {
56  case AV_CODEC_ID_PCM_S8:
57  case AV_CODEC_ID_PCM_S16LE:
58  case AV_CODEC_ID_PCM_S16BE:
59  case AV_CODEC_ID_PCM_S24LE:
60  case AV_CODEC_ID_PCM_S24BE:
61  case AV_CODEC_ID_PCM_S32LE:
62  case AV_CODEC_ID_PCM_S32BE:
63  case AV_CODEC_ID_PCM_F32LE:
64  case AV_CODEC_ID_PCM_F32BE:
65  case AV_CODEC_ID_PCM_F64LE:
66  case AV_CODEC_ID_PCM_F64BE:
67  case AV_CODEC_ID_PCM_ALAW:
68  case AV_CODEC_ID_PCM_MULAW:
69  return 1;
70  case AV_CODEC_ID_MACE3:
71  case AV_CODEC_ID_MACE6:
72  return 6;
73  case AV_CODEC_ID_ADPCM_IMA_QT:
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_ALAC:
90  case AV_CODEC_ID_QDM2:
91  return 4096;
92  case AV_CODEC_ID_ADPCM_IMA_WAV:
93  return (1024 - 4 * channels) * 8 / (4 * channels) + 1;
94  case AV_CODEC_ID_ADPCM_MS:
95  return (1024 - 7 * channels) * 2 / channels + 2;
96  default:
97  return 0;
98  }
99 }
100 
101  static int caf_write_header(AVFormatContext *s)
102 {
103  AVIOContext *pb = s->pb;
104  AVCodecContext *enc = s->streams[0]->codec;
105  CAFContext *caf = s->priv_data;
106  AVDictionaryEntry *t = NULL;
107  unsigned int codec_tag = ff_codec_get_tag(ff_codec_caf_tags, enc->codec_id);
108  int64_t chunk_size = 0;
109 
110  switch (enc->codec_id) {
111  case AV_CODEC_ID_AAC:
112  case AV_CODEC_ID_AC3:
113  av_log(s, AV_LOG_ERROR, "muxing codec currently unsupported\n");
114  return AVERROR_PATCHWELCOME;
115  }
116 
117  switch (enc->codec_id) {
118  case AV_CODEC_ID_PCM_S8:
119  case AV_CODEC_ID_PCM_S16LE:
120  case AV_CODEC_ID_PCM_S16BE:
121  case AV_CODEC_ID_PCM_S24LE:
122  case AV_CODEC_ID_PCM_S24BE:
123  case AV_CODEC_ID_PCM_S32LE:
124  case AV_CODEC_ID_PCM_S32BE:
125  case AV_CODEC_ID_PCM_F32LE:
126  case AV_CODEC_ID_PCM_F32BE:
127  case AV_CODEC_ID_PCM_F64LE:
128  case AV_CODEC_ID_PCM_F64BE:
129  case AV_CODEC_ID_PCM_ALAW:
130  case AV_CODEC_ID_PCM_MULAW:
131  codec_tag = MKTAG('l','p','c','m');
132  }
133 
134  if (!codec_tag) {
135  av_log(s, AV_LOG_ERROR, "unsupported codec\n");
136  return AVERROR_INVALIDDATA;
137  }
138 
139  if (!enc->block_align && !pb->seekable) {
140  av_log(s, AV_LOG_ERROR, "Muxing variable packet size not supported on non seekable output\n");
141  return AVERROR_INVALIDDATA;
142  }
143 
144  ffio_wfourcc(pb, "caff"); //< mFileType
145  avio_wb16(pb, 1); //< mFileVersion
146  avio_wb16(pb, 0); //< mFileFlags
147 
148  ffio_wfourcc(pb, "desc"); //< Audio Description chunk
149  avio_wb64(pb, 32); //< mChunkSize
150  avio_wb64(pb, av_double2int(enc->sample_rate)); //< mSampleRate
151  avio_wl32(pb, codec_tag); //< mFormatID
152  avio_wb32(pb, codec_flags(enc->codec_id)); //< mFormatFlags
153  avio_wb32(pb, enc->block_align); //< mBytesPerPacket
154  avio_wb32(pb, samples_per_packet(enc->codec_id, enc->channels)); //< mFramesPerPacket
155  avio_wb32(pb, enc->channels); //< mChannelsPerFrame
156  avio_wb32(pb, av_get_bits_per_sample(enc->codec_id)); //< mBitsPerChannel
157 
158  if (enc->channel_layout) {
159  ffio_wfourcc(pb, "chan");
160  avio_wb64(pb, 12);
161  ff_mov_write_chan(pb, enc->channel_layout);
162  }
163 
164  if (enc->codec_id == AV_CODEC_ID_ALAC) {
165  ffio_wfourcc(pb, "kuki");
166  avio_wb64(pb, 12 + enc->extradata_size);
167  avio_write(pb, "0円0円0円14円frmaalac", 12);
168  avio_write(pb, enc->extradata, enc->extradata_size);
169  } else if (enc->codec_id == AV_CODEC_ID_AMR_NB) {
170  ffio_wfourcc(pb, "kuki");
171  avio_wb64(pb, 29);
172  avio_write(pb, "0円0円0円14円frmasamr", 12);
173  avio_wb32(pb, 0x11); /* size */
174  avio_write(pb, "samrFFMP", 8);
175  avio_w8(pb, 0); /* decoder version */
176 
177  avio_wb16(pb, 0x81FF); /* Mode set (all modes for AMR_NB) */
178  avio_w8(pb, 0x00); /* Mode change period (no restriction) */
179  avio_w8(pb, 0x01); /* Frames per sample */
180  } else if (enc->codec_id == AV_CODEC_ID_QDM2) {
181  ffio_wfourcc(pb, "kuki");
182  avio_wb64(pb, enc->extradata_size);
183  avio_write(pb, enc->extradata, enc->extradata_size);
184  }
185 
186  if (av_dict_count(s->metadata)) {
187  ffio_wfourcc(pb, "info"); //< Information chunk
188  while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
189  chunk_size += strlen(t->key) + strlen(t->value) + 2;
190  }
191  avio_wb64(pb, chunk_size + 4);
192  avio_wb32(pb, av_dict_count(s->metadata));
193  t = NULL;
194  while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
195  avio_put_str(pb, t->key);
196  avio_put_str(pb, t->value);
197  }
198  }
199 
200  ffio_wfourcc(pb, "data"); //< Audio Data chunk
201  caf->data = avio_tell(pb);
202  avio_wb64(pb, -1); //< mChunkSize
203  avio_wb32(pb, 0); //< mEditCount
204 
205  avio_flush(pb);
206  return 0;
207 }
208 
209  static int caf_write_packet(AVFormatContext *s, AVPacket *pkt)
210 {
211  CAFContext *caf = s->priv_data;
212 
213  avio_write(s->pb, pkt->data, pkt->size);
214  if (!s->streams[0]->codec->block_align) {
215  void *pkt_sizes = caf->pkt_sizes;
216  int i, alloc_size = caf->size_entries_used + 5;
217  if (alloc_size < 0) {
218  caf->pkt_sizes = NULL;
219  } else {
220  caf->pkt_sizes = av_fast_realloc(caf->pkt_sizes,
221  &caf->size_buffer_size,
222  alloc_size);
223  }
224  if (!caf->pkt_sizes) {
225  av_free(pkt_sizes);
226  return AVERROR(ENOMEM);
227  }
228  for (i = 4; i > 0; i--) {
229  unsigned top = pkt->size >> i * 7;
230  if (top)
231  caf->pkt_sizes[caf->size_entries_used++] = 128 | top;
232  }
233  caf->pkt_sizes[caf->size_entries_used++] = pkt->size & 127;
234  caf->packets++;
235  }
236  return 0;
237 }
238 
239  static int caf_write_trailer(AVFormatContext *s)
240 {
241  AVIOContext *pb = s->pb;
242  AVCodecContext *enc = s->streams[0]->codec;
243 
244  if (pb->seekable) {
245  CAFContext *caf = s->priv_data;
246  int64_t file_size = avio_tell(pb);
247 
248  avio_seek(pb, caf->data, SEEK_SET);
249  avio_wb64(pb, file_size - caf->data - 8);
250  avio_seek(pb, file_size, SEEK_SET);
251  if (!enc->block_align) {
252  ffio_wfourcc(pb, "pakt");
253  avio_wb64(pb, caf->size_entries_used + 24);
254  avio_wb64(pb, caf->packets); ///< mNumberPackets
255  avio_wb64(pb, caf->packets * samples_per_packet(enc->codec_id, enc->channels)); ///< mNumberValidFrames
256  avio_wb32(pb, 0); ///< mPrimingFrames
257  avio_wb32(pb, 0); ///< mRemainderFrames
258  avio_write(pb, caf->pkt_sizes, caf->size_entries_used);
259  av_freep(&caf->pkt_sizes);
260  caf->size_buffer_size = 0;
261  }
262  avio_flush(pb);
263  }
264  return 0;
265 }
266 
267  AVOutputFormat ff_caf_muxer = {
268  .name = "caf",
269  .long_name = NULL_IF_CONFIG_SMALL("Apple CAF (Core Audio Format)"),
270  .mime_type = "audio/x-caf",
271  .extensions = "caf",
272  .priv_data_size = sizeof(CAFContext),
273  .audio_codec = AV_CODEC_ID_PCM_S16BE,
274  .video_codec = AV_CODEC_ID_NONE,
275  .write_header = caf_write_header,
276  .write_packet = caf_write_packet,
277  .write_trailer = caf_write_trailer,
278  .codec_tag = (const AVCodecTag* const []){ff_codec_caf_tags, 0},
279 };
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