xref: /btstack/src/classic/btstack_sbc_decoder_bluedroid.c (revision 6973c35a87cc7f398c429d8942b18d0a401e28a3)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define __BTSTACK_FILE__ "btstack_sbc_decoder_bluedroid.c"
39 
40 // *****************************************************************************
41 //
42 // SBC decoder based on Bluedroid library
43 //
44 // *****************************************************************************
45 
46 #include "btstack_config.h"
47 
48 #include <stdint.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 
53 #include "btstack_sbc.h"
54 #include "btstack_sbc_plc.h"
55 
56 #include "oi_codec_sbc.h"
57 #include "oi_assert.h"
58 #include "btstack.h"
59 
60 #define mSBC_SYNCWORD 0xad
61 #define SBC_SYNCWORD 0x9c
62 #define SBC_MAX_CHANNELS 2
63 // #define LOG_FRAME_STATUS
64 
65 #define DECODER_DATA_SIZE (SBC_MAX_CHANNELS*SBC_MAX_BLOCKS*SBC_MAX_BANDS * 4 + SBC_CODEC_MIN_FILTER_BUFFERS*SBC_MAX_BANDS*SBC_MAX_CHANNELS * 2)
66 
67 typedef struct {
68     OI_UINT32 bytes_in_frame_buffer;
69     OI_CODEC_SBC_DECODER_CONTEXT decoder_context;
70 
71     uint8_t frame_buffer[SBC_MAX_FRAME_LEN];
72     int16_t pcm_plc_data[SBC_MAX_CHANNELS * SBC_MAX_BANDS * SBC_MAX_BLOCKS];
73     int16_t pcm_data[SBC_MAX_CHANNELS * SBC_MAX_BANDS * SBC_MAX_BLOCKS];
74     uint32_t pcm_bytes;
75     OI_UINT32 decoder_data[(DECODER_DATA_SIZE+3)/4];
76     int h2_sequence_nr;
77     int search_new_sync_word;
78     int sync_word_found;
79     int first_good_frame_found;
80 } bludroid_decoder_state_t;
81 
82 static btstack_sbc_decoder_state_t * sbc_decoder_state_singleton = NULL;
83 static bludroid_decoder_state_t bd_decoder_state;
84 
85 // Testing only - START
86 static int plc_enabled = 1;
87 static int corrupt_frame_period = -1;
88 // Testing - STOP
89 
90 void btstack_sbc_decoder_test_disable_plc(void){
91     plc_enabled = 0;
92 }
93 
94 void btstack_sbc_decoder_test_simulate_corrupt_frames(int period){
95     corrupt_frame_period = period;
96 }
97 
98 static int find_sequence_of_zeros(const OI_BYTE *frame_data, OI_UINT32 frame_bytes, int seq_length){
99     int zero_seq_count = 0;
100     unsigned int i;
101     for (i=0; i<frame_bytes; i++){
102         if (frame_data[i] == 0) {
103             zero_seq_count++;
104             if (zero_seq_count >= seq_length) return zero_seq_count;
105         } else {
106             zero_seq_count = 0;
107         }
108     }
109     return 0;
110 }
111 
112 static int find_h2_syncword(const OI_BYTE *frame_data, OI_UINT32 frame_bytes){
113     int syncword = mSBC_SYNCWORD;
114     uint8_t h2_first_byte = 0;
115     uint8_t h2_second_byte = 0;
116 
117     unsigned int i;
118     for (i=0; i<frame_bytes; i++){
119         if (frame_data[i] == syncword) {
120             break;
121         }
122         h2_first_byte = h2_second_byte;
123         h2_second_byte = frame_data[i];
124     }
125     if (h2_first_byte != 1) return -1;
126 
127     // check if upper nibble of second byte is 0x08
128     uint8_t ln = h2_second_byte & 0x0F;
129     if (ln != 8) return -1;
130 
131     // check that bits 0+2 == bits 1+3
132     uint8_t hn = h2_second_byte >> 4;
133     if  ( ((hn>>1) & 0x05) != (hn & 0x05) ) return -1;
134 
135     return ((hn & 0x04) >> 1) | (hn & 0x01);
136 }
137 
138 int btstack_sbc_decoder_num_samples_per_frame(btstack_sbc_decoder_state_t * state){
139     bludroid_decoder_state_t * decoder_state = (bludroid_decoder_state_t *) state->decoder_state;
140     return decoder_state->decoder_context.common.frameInfo.nrof_blocks * decoder_state->decoder_context.common.frameInfo.nrof_subbands;
141 }
142 
143 int btstack_sbc_decoder_num_channels(btstack_sbc_decoder_state_t * state){
144     bludroid_decoder_state_t * decoder_state = (bludroid_decoder_state_t *) state->decoder_state;
145     return decoder_state->decoder_context.common.frameInfo.nrof_channels;
146 }
147 
148 int btstack_sbc_decoder_sample_rate(btstack_sbc_decoder_state_t * state){
149     bludroid_decoder_state_t * decoder_state = (bludroid_decoder_state_t *) state->decoder_state;
150     return decoder_state->decoder_context.common.frameInfo.frequency;
151 }
152 
153 #ifdef OI_DEBUG
154 void OI_AssertFail(const char* file, int line, const char* reason){
155     log_error("AssertFail file %s, line %d, reason %s", file, line, reason);
156 }
157 #endif
158 
159 void btstack_sbc_decoder_init(btstack_sbc_decoder_state_t * state, btstack_sbc_mode_t mode, void (*callback)(int16_t * data, int num_samples, int num_channels, int sample_rate, void * context), void * context){
160     if (sbc_decoder_state_singleton && sbc_decoder_state_singleton != state ){
161         log_error("SBC decoder: different sbc decoder state is allready registered");
162     }
163     OI_STATUS status = OI_STATUS_SUCCESS;
164     switch (mode){
165         case SBC_MODE_STANDARD:
166             // note: we always request stereo output, even for mono input
167             status = OI_CODEC_SBC_DecoderReset(&(bd_decoder_state.decoder_context), bd_decoder_state.decoder_data, sizeof(bd_decoder_state.decoder_data), 2, 2, FALSE);
168             break;
169         case SBC_MODE_mSBC:
170             status = OI_CODEC_mSBC_DecoderReset(&(bd_decoder_state.decoder_context), bd_decoder_state.decoder_data, sizeof(bd_decoder_state.decoder_data));
171             break;
172         default:
173             break;
174     }
175 
176     if (status != OI_STATUS_SUCCESS){
177         log_error("SBC decoder: error during reset %d\n", status);
178     }
179 
180     sbc_decoder_state_singleton = state;
181 
182     bd_decoder_state.bytes_in_frame_buffer = 0;
183     bd_decoder_state.pcm_bytes = sizeof(bd_decoder_state.pcm_data);
184     bd_decoder_state.h2_sequence_nr = -1;
185     bd_decoder_state.sync_word_found = 0;
186     bd_decoder_state.search_new_sync_word = 0;
187     if (mode == SBC_MODE_mSBC){
188         bd_decoder_state.search_new_sync_word = 1;
189     }
190     bd_decoder_state.first_good_frame_found = 0;
191 
192     memset(state, 0, sizeof(btstack_sbc_decoder_state_t));
193     state->handle_pcm_data = callback;
194     state->mode = mode;
195     state->context = context;
196     state->decoder_state = &bd_decoder_state;
197     btstack_sbc_plc_init(&state->plc_state);
198 }
199 
200 static void append_received_sbc_data(bludroid_decoder_state_t * state, uint8_t * buffer, int size){
201     int numFreeBytes = sizeof(state->frame_buffer) - state->bytes_in_frame_buffer;
202 
203     if (size > numFreeBytes){
204         log_error("SBC data: more bytes read %u than free bytes in buffer %u", size, numFreeBytes);
205     }
206 
207     memcpy(state->frame_buffer + state->bytes_in_frame_buffer, buffer, size);
208     state->bytes_in_frame_buffer += size;
209 }
210 
211 
212 static void btstack_sbc_decoder_process_sbc_data(btstack_sbc_decoder_state_t * state, uint8_t * buffer, int size){
213     bludroid_decoder_state_t * decoder_state = (bludroid_decoder_state_t*)state->decoder_state;
214     int input_bytes_to_process = size;
215     int keep_decoding = 1;
216 
217     while (keep_decoding) {
218         // Fill decoder_state->frame_buffer as much as possible.
219         int bytes_free_in_frame_buffer = SBC_MAX_FRAME_LEN - decoder_state->bytes_in_frame_buffer;
220         int bytes_to_append = btstack_min(input_bytes_to_process, bytes_free_in_frame_buffer);
221         if (bytes_to_append){
222             append_received_sbc_data(decoder_state, buffer, bytes_to_append);
223             buffer += bytes_to_append;
224             input_bytes_to_process -= bytes_to_append;
225         }
226 
227         // Decode the next frame in decoder_state->frame_buffer.
228         int bytes_in_frame_buffer_before_decoding = decoder_state->bytes_in_frame_buffer;
229         const OI_BYTE *frame_data = decoder_state->frame_buffer;
230         OI_UINT32 frame_data_len = decoder_state->bytes_in_frame_buffer;
231         OI_STATUS status = OI_CODEC_SBC_DecodeFrame(&(decoder_state->decoder_context),
232                                                     &frame_data,
233                                                     &frame_data_len,
234                                                     decoder_state->pcm_plc_data,
235                                                     &(decoder_state->pcm_bytes));
236         uint16_t bytes_processed = bytes_in_frame_buffer_before_decoding - frame_data_len;
237 
238         static int frame_count = 0;
239         if (corrupt_frame_period > 0){
240             frame_count++;
241 
242             if (frame_count % corrupt_frame_period == 0){
243                 *(uint8_t*)&frame_data[5] = 0;
244                 frame_count = 0;
245             }
246         }
247 
248         // Handle decoding result.
249         switch(status){
250             case OI_STATUS_SUCCESS:
251             case OI_CODEC_SBC_PARTIAL_DECODE:
252                 state->handle_pcm_data(decoder_state->pcm_plc_data,
253                                        btstack_sbc_decoder_num_samples_per_frame(state),
254                                        btstack_sbc_decoder_num_channels(state),
255                                        btstack_sbc_decoder_sample_rate(state), state->context);
256                 state->good_frames_nr++;
257                 break;
258 
259             case OI_CODEC_SBC_NOT_ENOUGH_HEADER_DATA:
260             case OI_CODEC_SBC_NOT_ENOUGH_BODY_DATA:
261             case OI_CODEC_SBC_NOT_ENOUGH_AUDIO_DATA:
262                 if (input_bytes_to_process > 0){
263                     // Should never occur: The SBC code claims there is not enough bytes in the frame_buffer,
264                     // but the frame_buffer was full. (The frame_buffer is always full before decoding when input_bytes_to_process > 0.)
265                     // Clear frame_buffer.
266                     log_info("SBC decode: frame_buffer too small for frame");
267                     bytes_processed = bytes_in_frame_buffer_before_decoding;
268                 } else {
269                     // Exit decode loop, because there is not enough data in frame_buffer to decode the next frame.
270                     keep_decoding = 0;
271                 }
272                 break;
273 
274             case OI_CODEC_SBC_NO_SYNCWORD:
275                 // This means the entire frame_buffer did not contain the syncword.
276                 // Discard the frame_buffer contents.
277                 log_info("SBC decode: no syncword found");
278                 bytes_processed = bytes_in_frame_buffer_before_decoding;
279                 break;
280 
281             case OI_CODEC_SBC_CHECKSUM_MISMATCH:
282                 // The next frame is somehow corrupt.
283                 log_info("SBC decode: checksum error");
284                 // Did the codec consume any bytes?
285                 if (bytes_processed > 0){
286                     // Good. Nothing to do.
287                 } else {
288                     // Skip the bogus frame by skipping the header.
289                     bytes_processed = 1;
290                 }
291                 break;
292 
293             case OI_STATUS_INVALID_PARAMETERS:
294                 // This caused by corrupt frames.
295                 // The codec apparently does not recover from this.
296                 // Re-initialize the codec.
297                 log_info("SBC decode: invalid parameters: resetting codec");
298                 if (OI_CODEC_SBC_DecoderReset(&(bd_decoder_state.decoder_context), bd_decoder_state.decoder_data, sizeof(bd_decoder_state.decoder_data), 2, 2, FALSE) != OI_STATUS_SUCCESS){
299                     log_info("SBC decode: resetting codec failed");
300 
301                 }
302                 break;
303             default:
304                 // Anything else went wrong.
305                 // Skip a few bytes and try again.
306                 bytes_processed = 1;
307                 log_info("SBC decode: unknown status %d", status);
308                 break;
309         }
310 
311         // Remove decoded frame from decoder_state->frame_buffer.
312         if (bytes_processed > bytes_in_frame_buffer_before_decoding) {
313             bytes_processed = bytes_in_frame_buffer_before_decoding;
314         }
315         memmove(decoder_state->frame_buffer, decoder_state->frame_buffer + bytes_processed, bytes_in_frame_buffer_before_decoding - bytes_processed);
316         decoder_state->bytes_in_frame_buffer -= bytes_processed;
317     }
318 }
319 
320 
321 static void btstack_sbc_decoder_process_msbc_data(btstack_sbc_decoder_state_t * state, int packet_status_flag, uint8_t * buffer, int size){
322     bludroid_decoder_state_t * decoder_state = (bludroid_decoder_state_t*)state->decoder_state;
323     int input_bytes_to_process = size;
324     unsigned int msbc_frame_size = 57;
325 
326     // printf("<<-- enter -->>\n");
327     // printf("Process data: in buffer %u, new %u\n", decoder_state->bytes_in_frame_buffer, size);
328 
329     while (input_bytes_to_process > 0){
330 
331         // fill buffer with new data
332         int bytes_missing_for_complete_msbc_frame = msbc_frame_size - decoder_state->bytes_in_frame_buffer;
333         int bytes_to_append = btstack_min(input_bytes_to_process, bytes_missing_for_complete_msbc_frame);
334         if (bytes_to_append) {
335             append_received_sbc_data(decoder_state, buffer, bytes_to_append);
336             buffer += bytes_to_append;
337             input_bytes_to_process -= bytes_to_append;
338         }
339 
340         if (decoder_state->bytes_in_frame_buffer < msbc_frame_size){
341             // printf("not enough data %d > %d\n", msbc_frame_size, decoder_state->bytes_in_frame_buffer);
342             if (input_bytes_to_process){
343                 log_error("SHOULD NOT HAPPEN... not enough bytes, but bytes left to process");
344             }
345             break;
346         }
347 
348         uint16_t bytes_in_frame_buffer_before_decoding = decoder_state->bytes_in_frame_buffer;
349         uint16_t bytes_processed = 0;
350         const OI_BYTE *frame_data = decoder_state->frame_buffer;
351 
352         static int frame_count = 0;
353         if (corrupt_frame_period > 0){
354            frame_count++;
355 
356             if (frame_count % corrupt_frame_period == 0){
357                 *(uint8_t*)&frame_data[5] = 0;
358                 frame_count = 0;
359             }
360         }
361 
362         OI_STATUS status = OI_STATUS_SUCCESS;
363         int bad_frame = 0;
364         int zero_seq_found = 0;
365 
366         if (decoder_state->first_good_frame_found){
367             zero_seq_found = find_sequence_of_zeros(frame_data, decoder_state->bytes_in_frame_buffer, 20);
368             bad_frame = zero_seq_found || packet_status_flag;
369         }
370 
371         if (bad_frame){
372             status = OI_CODEC_SBC_CHECKSUM_MISMATCH;
373             decoder_state->bytes_in_frame_buffer = 0;
374         } else {
375             if (decoder_state->search_new_sync_word && !decoder_state->sync_word_found){
376                 int h2_syncword = find_h2_syncword(frame_data, decoder_state->bytes_in_frame_buffer);
377 
378                 if (h2_syncword != -1){
379                     decoder_state->sync_word_found = 1;
380                     decoder_state->h2_sequence_nr = h2_syncword;
381                 }
382             }
383             status = OI_CODEC_SBC_DecodeFrame(&(decoder_state->decoder_context),
384                                                 &frame_data,
385                                                 &(decoder_state->bytes_in_frame_buffer),
386                                                 decoder_state->pcm_plc_data,
387                                                 &(decoder_state->pcm_bytes));
388         }
389 
390         bytes_processed = bytes_in_frame_buffer_before_decoding - decoder_state->bytes_in_frame_buffer;
391         OI_UINT32 bytes_in_frame_buffer = msbc_frame_size;
392 
393         switch(status){
394             case 0:
395                 decoder_state->first_good_frame_found = 1;
396                 decoder_state->search_new_sync_word = 1;
397                 decoder_state->sync_word_found = 0;
398 
399                 btstack_sbc_plc_good_frame(&state->plc_state, decoder_state->pcm_plc_data, decoder_state->pcm_data);
400                 state->handle_pcm_data(decoder_state->pcm_data,
401                                     btstack_sbc_decoder_num_samples_per_frame(state),
402                                     btstack_sbc_decoder_num_channels(state),
403                                     btstack_sbc_decoder_sample_rate(state), state->context);
404                 state->good_frames_nr++;
405                 continue;
406             case OI_CODEC_SBC_NOT_ENOUGH_HEADER_DATA:
407             case OI_CODEC_SBC_NOT_ENOUGH_BODY_DATA:
408             case OI_CODEC_SBC_NOT_ENOUGH_AUDIO_DATA:
409                 // printf("    NOT_ENOUGH_DATA\n");
410                 if (decoder_state->sync_word_found){
411                     decoder_state->search_new_sync_word = 0;
412                 }
413                 break;
414             case OI_CODEC_SBC_NO_SYNCWORD:
415             case OI_CODEC_SBC_CHECKSUM_MISMATCH:
416                 // printf("NO_SYNCWORD or CHECKSUM_MISMATCH\n");
417                 decoder_state->bytes_in_frame_buffer = 0;
418                 if (!decoder_state->first_good_frame_found) break;
419 
420                 if (!decoder_state->sync_word_found){
421                     decoder_state->h2_sequence_nr = (decoder_state->h2_sequence_nr + 1)%4;
422                 }
423                 decoder_state->search_new_sync_word = 1;
424                 decoder_state->sync_word_found = 0;
425 
426                 if (zero_seq_found){
427                     state->zero_frames_nr++;
428                 } else {
429                     state->bad_frames_nr++;
430                 }
431 
432 #ifdef LOG_FRAME_STATUS
433                 if (zero_seq_found){
434                     printf("%d : ZERO FRAME\n", decoder_state->h2_sequence_nr);
435                 } else {
436                     printf("%d : BAD FRAME\n", decoder_state->h2_sequence_nr);
437                 }
438                 if (decoder_state->h2_sequence_nr == 3) printf("\n");
439 #endif
440                 if (!plc_enabled) break;
441 
442                 frame_data = btstack_sbc_plc_zero_signal_frame();
443                 status = OI_CODEC_SBC_DecodeFrame(&(decoder_state->decoder_context),
444                                                     &frame_data,
445                                                     &bytes_in_frame_buffer,
446                                                     decoder_state->pcm_plc_data,
447                                                     &(decoder_state->pcm_bytes));
448 
449                 if (status != 0) {
450                     log_error("SBC decoder: error %d\n", status);
451                 }
452                 btstack_sbc_plc_bad_frame(&state->plc_state, decoder_state->pcm_plc_data, decoder_state->pcm_data);
453                 state->handle_pcm_data(decoder_state->pcm_data,
454                                     btstack_sbc_decoder_num_samples_per_frame(state),
455                                     btstack_sbc_decoder_num_channels(state),
456                                     btstack_sbc_decoder_sample_rate(state), state->context);
457 
458 
459                 break;
460             case OI_STATUS_INVALID_PARAMETERS:
461                 // This caused by corrupt frames.
462                 // The codec apparently does not recover from this.
463                 // Re-initialize the codec.
464                 log_info("SBC decode: invalid parameters: resetting codec");
465                 if (OI_CODEC_mSBC_DecoderReset(&(bd_decoder_state.decoder_context), bd_decoder_state.decoder_data, sizeof(bd_decoder_state.decoder_data)) != OI_STATUS_SUCCESS){
466                     log_info("SBC decode: resetting codec failed");
467 
468                 }
469                 break;
470             default:
471                 log_info("Frame decode error: %d", status);
472                 break;
473         }
474 
475         memmove(decoder_state->frame_buffer, decoder_state->frame_buffer + bytes_processed, decoder_state->bytes_in_frame_buffer);
476     }
477 }
478 
479 void btstack_sbc_decoder_process_data(btstack_sbc_decoder_state_t * state, int packet_status_flag, uint8_t * buffer, int size){
480     if (state->mode == SBC_MODE_mSBC){
481         btstack_sbc_decoder_process_msbc_data(state, packet_status_flag, buffer, size);
482     } else {
483         btstack_sbc_decoder_process_sbc_data(state, buffer, size);
484     }
485 }
486