1 |
|
|
/* |
2 |
|
|
* Bluetooth low-complexity, subband codec (SBC) |
3 |
|
|
* |
4 |
|
|
* Copyright (C) 2017 Aurelien Jacobs <aurel@gnuage.org> |
5 |
|
|
* Copyright (C) 2012-2013 Intel Corporation |
6 |
|
|
* Copyright (C) 2008-2010 Nokia Corporation |
7 |
|
|
* Copyright (C) 2004-2010 Marcel Holtmann <marcel@holtmann.org> |
8 |
|
|
* Copyright (C) 2004-2005 Henryk Ploetz <henryk@ploetzli.ch> |
9 |
|
|
* Copyright (C) 2005-2008 Brad Midgley <bmidgley@xmission.com> |
10 |
|
|
* |
11 |
|
|
* This file is part of FFmpeg. |
12 |
|
|
* |
13 |
|
|
* FFmpeg is free software; you can redistribute it and/or |
14 |
|
|
* modify it under the terms of the GNU Lesser General Public |
15 |
|
|
* License as published by the Free Software Foundation; either |
16 |
|
|
* version 2.1 of the License, or (at your option) any later version. |
17 |
|
|
* |
18 |
|
|
* FFmpeg is distributed in the hope that it will be useful, |
19 |
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
20 |
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
21 |
|
|
* Lesser General Public License for more details. |
22 |
|
|
* |
23 |
|
|
* You should have received a copy of the GNU Lesser General Public |
24 |
|
|
* License along with FFmpeg; if not, write to the Free Software |
25 |
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
26 |
|
|
*/ |
27 |
|
|
|
28 |
|
|
/** |
29 |
|
|
* @file |
30 |
|
|
* SBC decoder implementation |
31 |
|
|
*/ |
32 |
|
|
|
33 |
|
|
#include "avcodec.h" |
34 |
|
|
#include "internal.h" |
35 |
|
|
#include "libavutil/intreadwrite.h" |
36 |
|
|
#include "sbc.h" |
37 |
|
|
#include "sbcdec_data.h" |
38 |
|
|
|
39 |
|
|
struct sbc_decoder_state { |
40 |
|
|
int32_t V[2][170]; |
41 |
|
|
int offset[2][16]; |
42 |
|
|
}; |
43 |
|
|
|
44 |
|
|
typedef struct SBCDecContext { |
45 |
|
|
AVClass *class; |
46 |
|
|
DECLARE_ALIGNED(SBC_ALIGN, struct sbc_frame, frame); |
47 |
|
|
DECLARE_ALIGNED(SBC_ALIGN, struct sbc_decoder_state, dsp); |
48 |
|
|
} SBCDecContext; |
49 |
|
|
|
50 |
|
|
/* |
51 |
|
|
* Unpacks a SBC frame at the beginning of the stream in data, |
52 |
|
|
* which has at most len bytes into frame. |
53 |
|
|
* Returns the length in bytes of the packed frame, or a negative |
54 |
|
|
* value on error. The error codes are: |
55 |
|
|
* |
56 |
|
|
* -1 Data stream too short |
57 |
|
|
* -2 Sync byte incorrect |
58 |
|
|
* -3 CRC8 incorrect |
59 |
|
|
* -4 Bitpool value out of bounds |
60 |
|
|
*/ |
61 |
|
|
static int sbc_unpack_frame(const uint8_t *data, struct sbc_frame *frame, |
62 |
|
|
size_t len) |
63 |
|
|
{ |
64 |
|
|
unsigned int consumed; |
65 |
|
|
/* Will copy the parts of the header that are relevant to crc |
66 |
|
|
* calculation here */ |
67 |
|
|
uint8_t crc_header[11] = { 0 }; |
68 |
|
|
int crc_pos; |
69 |
|
|
int32_t temp; |
70 |
|
|
|
71 |
|
|
uint32_t audio_sample; |
72 |
|
|
int ch, sb, blk, bit; /* channel, subband, block and bit standard |
73 |
|
|
counters */ |
74 |
|
|
int bits[2][8]; /* bits distribution */ |
75 |
|
|
uint32_t levels[2][8]; /* levels derived from that */ |
76 |
|
|
|
77 |
|
|
if (len < 4) |
78 |
|
|
return -1; |
79 |
|
|
|
80 |
|
|
if (data[0] == MSBC_SYNCWORD) { |
81 |
|
|
if (data[1] != 0) |
82 |
|
|
return -2; |
83 |
|
|
if (data[2] != 0) |
84 |
|
|
return -2; |
85 |
|
|
|
86 |
|
|
frame->frequency = SBC_FREQ_16000; |
87 |
|
|
frame->blocks = MSBC_BLOCKS; |
88 |
|
|
frame->allocation = LOUDNESS; |
89 |
|
|
frame->mode = MONO; |
90 |
|
|
frame->channels = 1; |
91 |
|
|
frame->subbands = 8; |
92 |
|
|
frame->bitpool = 26; |
93 |
|
|
} else if (data[0] == SBC_SYNCWORD) { |
94 |
|
|
frame->frequency = (data[1] >> 6) & 0x03; |
95 |
|
|
frame->blocks = 4 * ((data[1] >> 4) & 0x03) + 4; |
96 |
|
|
frame->mode = (data[1] >> 2) & 0x03; |
97 |
|
|
frame->channels = frame->mode == MONO ? 1 : 2; |
98 |
|
|
frame->allocation = (data[1] >> 1) & 0x01; |
99 |
|
|
frame->subbands = data[1] & 0x01 ? 8 : 4; |
100 |
|
|
frame->bitpool = data[2]; |
101 |
|
|
|
102 |
|
|
if ((frame->mode == MONO || frame->mode == DUAL_CHANNEL) && |
103 |
|
|
frame->bitpool > 16 * frame->subbands) |
104 |
|
|
return -4; |
105 |
|
|
|
106 |
|
|
if ((frame->mode == STEREO || frame->mode == JOINT_STEREO) && |
107 |
|
|
frame->bitpool > 32 * frame->subbands) |
108 |
|
|
return -4; |
109 |
|
|
} else |
110 |
|
|
return -2; |
111 |
|
|
|
112 |
|
|
consumed = 32; |
113 |
|
|
crc_header[0] = data[1]; |
114 |
|
|
crc_header[1] = data[2]; |
115 |
|
|
crc_pos = 16; |
116 |
|
|
|
117 |
|
|
if (frame->mode == JOINT_STEREO) { |
118 |
|
|
if (len * 8 < consumed + frame->subbands) |
119 |
|
|
return -1; |
120 |
|
|
|
121 |
|
|
frame->joint = 0x00; |
122 |
|
|
for (sb = 0; sb < frame->subbands - 1; sb++) |
123 |
|
|
frame->joint |= ((data[4] >> (7 - sb)) & 0x01) << sb; |
124 |
|
|
if (frame->subbands == 4) |
125 |
|
|
crc_header[crc_pos / 8] = data[4] & 0xf0; |
126 |
|
|
else |
127 |
|
|
crc_header[crc_pos / 8] = data[4]; |
128 |
|
|
|
129 |
|
|
consumed += frame->subbands; |
130 |
|
|
crc_pos += frame->subbands; |
131 |
|
|
} |
132 |
|
|
|
133 |
|
|
if (len * 8 < consumed + (4 * frame->subbands * frame->channels)) |
134 |
|
|
return -1; |
135 |
|
|
|
136 |
|
|
for (ch = 0; ch < frame->channels; ch++) { |
137 |
|
|
for (sb = 0; sb < frame->subbands; sb++) { |
138 |
|
|
/* FIXME assert(consumed % 4 == 0); */ |
139 |
|
|
frame->scale_factor[ch][sb] = |
140 |
|
|
(data[consumed >> 3] >> (4 - (consumed & 0x7))) & 0x0F; |
141 |
|
|
crc_header[crc_pos >> 3] |= |
142 |
|
|
frame->scale_factor[ch][sb] << (4 - (crc_pos & 0x7)); |
143 |
|
|
|
144 |
|
|
consumed += 4; |
145 |
|
|
crc_pos += 4; |
146 |
|
|
} |
147 |
|
|
} |
148 |
|
|
|
149 |
|
|
if (data[3] != ff_sbc_crc8(frame->crc_ctx, crc_header, crc_pos)) |
150 |
|
|
return -3; |
151 |
|
|
|
152 |
|
|
ff_sbc_calculate_bits(frame, bits); |
153 |
|
|
|
154 |
|
|
for (ch = 0; ch < frame->channels; ch++) { |
155 |
|
|
for (sb = 0; sb < frame->subbands; sb++) |
156 |
|
|
levels[ch][sb] = (1 << bits[ch][sb]) - 1; |
157 |
|
|
} |
158 |
|
|
|
159 |
|
|
for (blk = 0; blk < frame->blocks; blk++) { |
160 |
|
|
for (ch = 0; ch < frame->channels; ch++) { |
161 |
|
|
for (sb = 0; sb < frame->subbands; sb++) { |
162 |
|
|
uint32_t shift; |
163 |
|
|
|
164 |
|
|
if (levels[ch][sb] == 0) { |
165 |
|
|
frame->sb_sample[blk][ch][sb] = 0; |
166 |
|
|
continue; |
167 |
|
|
} |
168 |
|
|
|
169 |
|
|
shift = frame->scale_factor[ch][sb] + |
170 |
|
|
1 + SBCDEC_FIXED_EXTRA_BITS; |
171 |
|
|
|
172 |
|
|
audio_sample = 0; |
173 |
|
|
for (bit = 0; bit < bits[ch][sb]; bit++) { |
174 |
|
|
if (consumed > len * 8) |
175 |
|
|
return -1; |
176 |
|
|
|
177 |
|
|
if ((data[consumed >> 3] >> (7 - (consumed & 0x7))) & 0x01) |
178 |
|
|
audio_sample |= 1 << (bits[ch][sb] - bit - 1); |
179 |
|
|
|
180 |
|
|
consumed++; |
181 |
|
|
} |
182 |
|
|
|
183 |
|
|
frame->sb_sample[blk][ch][sb] = (int32_t) |
184 |
|
|
(((((uint64_t) audio_sample << 1) | 1) << shift) / |
185 |
|
|
levels[ch][sb]) - (1 << shift); |
186 |
|
|
} |
187 |
|
|
} |
188 |
|
|
} |
189 |
|
|
|
190 |
|
|
if (frame->mode == JOINT_STEREO) { |
191 |
|
|
for (blk = 0; blk < frame->blocks; blk++) { |
192 |
|
|
for (sb = 0; sb < frame->subbands; sb++) { |
193 |
|
|
if (frame->joint & (0x01 << sb)) { |
194 |
|
|
temp = frame->sb_sample[blk][0][sb] + |
195 |
|
|
frame->sb_sample[blk][1][sb]; |
196 |
|
|
frame->sb_sample[blk][1][sb] = |
197 |
|
|
frame->sb_sample[blk][0][sb] - |
198 |
|
|
frame->sb_sample[blk][1][sb]; |
199 |
|
|
frame->sb_sample[blk][0][sb] = temp; |
200 |
|
|
} |
201 |
|
|
} |
202 |
|
|
} |
203 |
|
|
} |
204 |
|
|
|
205 |
|
|
if ((consumed & 0x7) != 0) |
206 |
|
|
consumed += 8 - (consumed & 0x7); |
207 |
|
|
|
208 |
|
|
return consumed >> 3; |
209 |
|
|
} |
210 |
|
|
|
211 |
|
|
static inline void sbc_synthesize_four(struct sbc_decoder_state *state, |
212 |
|
|
struct sbc_frame *frame, |
213 |
|
|
int ch, int blk, AVFrame *output_frame) |
214 |
|
|
{ |
215 |
|
|
int i, k, idx; |
216 |
|
|
int32_t *v = state->V[ch]; |
217 |
|
|
int *offset = state->offset[ch]; |
218 |
|
|
|
219 |
|
|
for (i = 0; i < 8; i++) { |
220 |
|
|
/* Shifting */ |
221 |
|
|
offset[i]--; |
222 |
|
|
if (offset[i] < 0) { |
223 |
|
|
offset[i] = 79; |
224 |
|
|
memcpy(v + 80, v, 9 * sizeof(*v)); |
225 |
|
|
} |
226 |
|
|
|
227 |
|
|
/* Distribute the new matrix value to the shifted position */ |
228 |
|
|
v[offset[i]] = |
229 |
|
|
(int)( (unsigned)ff_synmatrix4[i][0] * frame->sb_sample[blk][ch][0] + |
230 |
|
|
(unsigned)ff_synmatrix4[i][1] * frame->sb_sample[blk][ch][1] + |
231 |
|
|
(unsigned)ff_synmatrix4[i][2] * frame->sb_sample[blk][ch][2] + |
232 |
|
|
(unsigned)ff_synmatrix4[i][3] * frame->sb_sample[blk][ch][3] ) >> 15; |
233 |
|
|
} |
234 |
|
|
|
235 |
|
|
/* Compute the samples */ |
236 |
|
|
for (idx = 0, i = 0; i < 4; i++, idx += 5) { |
237 |
|
|
k = (i + 4) & 0xf; |
238 |
|
|
|
239 |
|
|
/* Store in output, Q0 */ |
240 |
|
|
AV_WN16A(&output_frame->data[ch][blk * 8 + i * 2], av_clip_int16( |
241 |
|
|
(int)( (unsigned)v[offset[i] + 0] * ff_sbc_proto_4_40m0[idx + 0] + |
242 |
|
|
(unsigned)v[offset[k] + 1] * ff_sbc_proto_4_40m1[idx + 0] + |
243 |
|
|
(unsigned)v[offset[i] + 2] * ff_sbc_proto_4_40m0[idx + 1] + |
244 |
|
|
(unsigned)v[offset[k] + 3] * ff_sbc_proto_4_40m1[idx + 1] + |
245 |
|
|
(unsigned)v[offset[i] + 4] * ff_sbc_proto_4_40m0[idx + 2] + |
246 |
|
|
(unsigned)v[offset[k] + 5] * ff_sbc_proto_4_40m1[idx + 2] + |
247 |
|
|
(unsigned)v[offset[i] + 6] * ff_sbc_proto_4_40m0[idx + 3] + |
248 |
|
|
(unsigned)v[offset[k] + 7] * ff_sbc_proto_4_40m1[idx + 3] + |
249 |
|
|
(unsigned)v[offset[i] + 8] * ff_sbc_proto_4_40m0[idx + 4] + |
250 |
|
|
(unsigned)v[offset[k] + 9] * ff_sbc_proto_4_40m1[idx + 4] ) >> 15)); |
251 |
|
|
} |
252 |
|
|
} |
253 |
|
|
|
254 |
|
|
static inline void sbc_synthesize_eight(struct sbc_decoder_state *state, |
255 |
|
|
struct sbc_frame *frame, |
256 |
|
|
int ch, int blk, AVFrame *output_frame) |
257 |
|
|
{ |
258 |
|
|
int i, k, idx; |
259 |
|
|
int32_t *v = state->V[ch]; |
260 |
|
|
int *offset = state->offset[ch]; |
261 |
|
|
|
262 |
|
|
for (i = 0; i < 16; i++) { |
263 |
|
|
/* Shifting */ |
264 |
|
|
offset[i]--; |
265 |
|
|
if (offset[i] < 0) { |
266 |
|
|
offset[i] = 159; |
267 |
|
|
memcpy(v + 160, v, 9 * sizeof(*v)); |
268 |
|
|
} |
269 |
|
|
|
270 |
|
|
/* Distribute the new matrix value to the shifted position */ |
271 |
|
|
v[offset[i]] = |
272 |
|
|
(int)( (unsigned)ff_synmatrix8[i][0] * frame->sb_sample[blk][ch][0] + |
273 |
|
|
(unsigned)ff_synmatrix8[i][1] * frame->sb_sample[blk][ch][1] + |
274 |
|
|
(unsigned)ff_synmatrix8[i][2] * frame->sb_sample[blk][ch][2] + |
275 |
|
|
(unsigned)ff_synmatrix8[i][3] * frame->sb_sample[blk][ch][3] + |
276 |
|
|
(unsigned)ff_synmatrix8[i][4] * frame->sb_sample[blk][ch][4] + |
277 |
|
|
(unsigned)ff_synmatrix8[i][5] * frame->sb_sample[blk][ch][5] + |
278 |
|
|
(unsigned)ff_synmatrix8[i][6] * frame->sb_sample[blk][ch][6] + |
279 |
|
|
(unsigned)ff_synmatrix8[i][7] * frame->sb_sample[blk][ch][7] ) >> 15; |
280 |
|
|
} |
281 |
|
|
|
282 |
|
|
/* Compute the samples */ |
283 |
|
|
for (idx = 0, i = 0; i < 8; i++, idx += 5) { |
284 |
|
|
k = (i + 8) & 0xf; |
285 |
|
|
|
286 |
|
|
/* Store in output, Q0 */ |
287 |
|
|
AV_WN16A(&output_frame->data[ch][blk * 16 + i * 2], av_clip_int16( |
288 |
|
|
(int)( (unsigned)v[offset[i] + 0] * ff_sbc_proto_8_80m0[idx + 0] + |
289 |
|
|
(unsigned)v[offset[k] + 1] * ff_sbc_proto_8_80m1[idx + 0] + |
290 |
|
|
(unsigned)v[offset[i] + 2] * ff_sbc_proto_8_80m0[idx + 1] + |
291 |
|
|
(unsigned)v[offset[k] + 3] * ff_sbc_proto_8_80m1[idx + 1] + |
292 |
|
|
(unsigned)v[offset[i] + 4] * ff_sbc_proto_8_80m0[idx + 2] + |
293 |
|
|
(unsigned)v[offset[k] + 5] * ff_sbc_proto_8_80m1[idx + 2] + |
294 |
|
|
(unsigned)v[offset[i] + 6] * ff_sbc_proto_8_80m0[idx + 3] + |
295 |
|
|
(unsigned)v[offset[k] + 7] * ff_sbc_proto_8_80m1[idx + 3] + |
296 |
|
|
(unsigned)v[offset[i] + 8] * ff_sbc_proto_8_80m0[idx + 4] + |
297 |
|
|
(unsigned)v[offset[k] + 9] * ff_sbc_proto_8_80m1[idx + 4] ) >> 15)); |
298 |
|
|
} |
299 |
|
|
} |
300 |
|
|
|
301 |
|
|
static void sbc_synthesize_audio(struct sbc_decoder_state *state, |
302 |
|
|
struct sbc_frame *frame, AVFrame *output_frame) |
303 |
|
|
{ |
304 |
|
|
int ch, blk; |
305 |
|
|
|
306 |
|
|
switch (frame->subbands) { |
307 |
|
|
case 4: |
308 |
|
|
for (ch = 0; ch < frame->channels; ch++) |
309 |
|
|
for (blk = 0; blk < frame->blocks; blk++) |
310 |
|
|
sbc_synthesize_four(state, frame, ch, blk, output_frame); |
311 |
|
|
break; |
312 |
|
|
|
313 |
|
|
case 8: |
314 |
|
|
for (ch = 0; ch < frame->channels; ch++) |
315 |
|
|
for (blk = 0; blk < frame->blocks; blk++) |
316 |
|
|
sbc_synthesize_eight(state, frame, ch, blk, output_frame); |
317 |
|
|
break; |
318 |
|
|
} |
319 |
|
|
} |
320 |
|
|
|
321 |
|
|
static int sbc_decode_init(AVCodecContext *avctx) |
322 |
|
|
{ |
323 |
|
|
SBCDecContext *sbc = avctx->priv_data; |
324 |
|
|
int i, ch; |
325 |
|
|
|
326 |
|
|
avctx->sample_fmt = AV_SAMPLE_FMT_S16P; |
327 |
|
|
|
328 |
|
|
sbc->frame.crc_ctx = av_crc_get_table(AV_CRC_8_EBU); |
329 |
|
|
|
330 |
|
|
memset(sbc->dsp.V, 0, sizeof(sbc->dsp.V)); |
331 |
|
|
for (ch = 0; ch < 2; ch++) |
332 |
|
|
for (i = 0; i < FF_ARRAY_ELEMS(sbc->dsp.offset[0]); i++) |
333 |
|
|
sbc->dsp.offset[ch][i] = (10 * i + 10); |
334 |
|
|
return 0; |
335 |
|
|
} |
336 |
|
|
|
337 |
|
|
static int sbc_decode_frame(AVCodecContext *avctx, |
338 |
|
|
void *data, int *got_frame_ptr, |
339 |
|
|
AVPacket *avpkt) |
340 |
|
|
{ |
341 |
|
|
SBCDecContext *sbc = avctx->priv_data; |
342 |
|
|
AVFrame *frame = data; |
343 |
|
|
int ret, frame_length; |
344 |
|
|
|
345 |
|
|
if (!sbc) |
346 |
|
|
return AVERROR(EIO); |
347 |
|
|
|
348 |
|
|
frame_length = sbc_unpack_frame(avpkt->data, &sbc->frame, avpkt->size); |
349 |
|
|
if (frame_length <= 0) |
350 |
|
|
return frame_length; |
351 |
|
|
|
352 |
|
|
avctx->channels = sbc->frame.channels; |
353 |
|
|
|
354 |
|
|
frame->nb_samples = sbc->frame.blocks * sbc->frame.subbands; |
355 |
|
|
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
356 |
|
|
return ret; |
357 |
|
|
|
358 |
|
|
sbc_synthesize_audio(&sbc->dsp, &sbc->frame, frame); |
359 |
|
|
|
360 |
|
|
*got_frame_ptr = 1; |
361 |
|
|
|
362 |
|
|
return frame_length; |
363 |
|
|
} |
364 |
|
|
|
365 |
|
|
AVCodec ff_sbc_decoder = { |
366 |
|
|
.name = "sbc", |
367 |
|
|
.long_name = NULL_IF_CONFIG_SMALL("SBC (low-complexity subband codec)"), |
368 |
|
|
.type = AVMEDIA_TYPE_AUDIO, |
369 |
|
|
.id = AV_CODEC_ID_SBC, |
370 |
|
|
.priv_data_size = sizeof(SBCDecContext), |
371 |
|
|
.init = sbc_decode_init, |
372 |
|
|
.decode = sbc_decode_frame, |
373 |
|
|
.capabilities = AV_CODEC_CAP_DR1, |
374 |
|
|
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, |
375 |
|
|
.channel_layouts = (const uint64_t[]) { AV_CH_LAYOUT_MONO, |
376 |
|
|
AV_CH_LAYOUT_STEREO, 0}, |
377 |
|
|
.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P, |
378 |
|
|
AV_SAMPLE_FMT_NONE }, |
379 |
|
|
.supported_samplerates = (const int[]) { 16000, 32000, 44100, 48000, 0 }, |
380 |
|
|
}; |