1 /*
2  * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "libavutil/common.h"
22 #include "libavutil/dict.h"
23 // #include "libavutil/error.h"
24 #include "libavutil/frame.h"
25 #include "libavutil/log.h"
26 #include "libavutil/mem.h"
27 #include "libavutil/opt.h"
28 
29 #include "avresample.h"
30 #include "internal.h"
31 #include "audio_data.h"
32 #include "audio_convert.h"
33 #include "audio_mix.h"
34 #include "resample.h"
35 
avresample_open(AVAudioResampleContext * avr)36 int avresample_open(AVAudioResampleContext *avr)
37 {
38     int ret;
39 
40     if (avresample_is_open(avr)) {
41         av_log(avr, AV_LOG_ERROR, "The resampling context is already open.\n");
42         return AVERROR(EINVAL);
43     }
44 
45     /* set channel mixing parameters */
46     avr->in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);
47     if (avr->in_channels <= 0 || avr->in_channels > AVRESAMPLE_MAX_CHANNELS) {
48         av_log(avr, AV_LOG_ERROR, "Invalid input channel layout: %"PRIu64"\n",
49                avr->in_channel_layout);
50         return AVERROR(EINVAL);
51     }
52     avr->out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);
53     if (avr->out_channels <= 0 || avr->out_channels > AVRESAMPLE_MAX_CHANNELS) {
54         av_log(avr, AV_LOG_ERROR, "Invalid output channel layout: %"PRIu64"\n",
55                avr->out_channel_layout);
56         return AVERROR(EINVAL);
57     }
58     avr->resample_channels = FFMIN(avr->in_channels, avr->out_channels);
59     avr->downmix_needed    = avr->in_channels  > avr->out_channels;
60     avr->upmix_needed      = avr->out_channels > avr->in_channels ||
61                              (!avr->downmix_needed && (avr->mix_matrix ||
62                               avr->in_channel_layout != avr->out_channel_layout));
63     avr->mixing_needed     = avr->downmix_needed || avr->upmix_needed;
64 
65     /* set resampling parameters */
66     avr->resample_needed   = avr->in_sample_rate != avr->out_sample_rate ||
67                              avr->force_resampling;
68 
69     /* select internal sample format if not specified by the user */
70     if (avr->internal_sample_fmt == AV_SAMPLE_FMT_NONE &&
71         (avr->mixing_needed || avr->resample_needed)) {
72         enum AVSampleFormat  in_fmt = av_get_planar_sample_fmt(avr->in_sample_fmt);
73         enum AVSampleFormat out_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);
74         int max_bps = FFMAX(av_get_bytes_per_sample(in_fmt),
75                             av_get_bytes_per_sample(out_fmt));
76         if (max_bps <= 2) {
77             avr->internal_sample_fmt = AV_SAMPLE_FMT_S16P;
78         } else if (avr->mixing_needed) {
79             avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;
80         } else {
81             if (max_bps <= 4) {
82                 if (in_fmt  == AV_SAMPLE_FMT_S32P ||
83                     out_fmt == AV_SAMPLE_FMT_S32P) {
84                     if (in_fmt  == AV_SAMPLE_FMT_FLTP ||
85                         out_fmt == AV_SAMPLE_FMT_FLTP) {
86                         /* if one is s32 and the other is flt, use dbl */
87                         avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;
88                     } else {
89                         /* if one is s32 and the other is s32, s16, or u8, use s32 */
90                         avr->internal_sample_fmt = AV_SAMPLE_FMT_S32P;
91                     }
92                 } else {
93                     /* if one is flt and the other is flt, s16 or u8, use flt */
94                     avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;
95                 }
96             } else {
97                 /* if either is dbl, use dbl */
98                 avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;
99             }
100         }
101         av_log(avr, AV_LOG_DEBUG, "Using %s as internal sample format\n",
102                av_get_sample_fmt_name(avr->internal_sample_fmt));
103     }
104 
105     /* we may need to add an extra conversion in order to remap channels if
106        the output format is not planar */
107     if (avr->use_channel_map && !avr->mixing_needed && !avr->resample_needed &&
108         !ff_sample_fmt_is_planar(avr->out_sample_fmt, avr->out_channels)) {
109         avr->internal_sample_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);
110     }
111 
112     /* set sample format conversion parameters */
113     if (avr->resample_needed || avr->mixing_needed)
114         avr->in_convert_needed = avr->in_sample_fmt != avr->internal_sample_fmt;
115     else
116         avr->in_convert_needed = avr->use_channel_map &&
117                                  !ff_sample_fmt_is_planar(avr->out_sample_fmt, avr->out_channels);
118 
119     if (avr->resample_needed || avr->mixing_needed || avr->in_convert_needed)
120         avr->out_convert_needed = avr->internal_sample_fmt != avr->out_sample_fmt;
121     else
122         avr->out_convert_needed = avr->in_sample_fmt != avr->out_sample_fmt;
123 
124     avr->in_copy_needed = !avr->in_convert_needed && (avr->mixing_needed ||
125                           (avr->use_channel_map && avr->resample_needed));
126 
127     if (avr->use_channel_map) {
128         if (avr->in_copy_needed) {
129             avr->remap_point = REMAP_IN_COPY;
130             av_log(avr, AV_LOG_TRACE, "remap channels during in_copy\n");
131         } else if (avr->in_convert_needed) {
132             avr->remap_point = REMAP_IN_CONVERT;
133             av_log(avr, AV_LOG_TRACE, "remap channels during in_convert\n");
134         } else if (avr->out_convert_needed) {
135             avr->remap_point = REMAP_OUT_CONVERT;
136             av_log(avr, AV_LOG_TRACE, "remap channels during out_convert\n");
137         } else {
138             avr->remap_point = REMAP_OUT_COPY;
139             av_log(avr, AV_LOG_TRACE, "remap channels during out_copy\n");
140         }
141 
142 #ifdef DEBUG
143         {
144             int ch;
145             av_log(avr, AV_LOG_TRACE, "output map: ");
146             if (avr->ch_map_info.do_remap)
147                 for (ch = 0; ch < avr->in_channels; ch++)
148                     av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.channel_map[ch]);
149             else
150                 av_log(avr, AV_LOG_TRACE, "n/a");
151             av_log(avr, AV_LOG_TRACE, "\n");
152             av_log(avr, AV_LOG_TRACE, "copy map:   ");
153             if (avr->ch_map_info.do_copy)
154                 for (ch = 0; ch < avr->in_channels; ch++)
155                     av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.channel_copy[ch]);
156             else
157                 av_log(avr, AV_LOG_TRACE, "n/a");
158             av_log(avr, AV_LOG_TRACE, "\n");
159             av_log(avr, AV_LOG_TRACE, "zero map:   ");
160             if (avr->ch_map_info.do_zero)
161                 for (ch = 0; ch < avr->in_channels; ch++)
162                     av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.channel_zero[ch]);
163             else
164                 av_log(avr, AV_LOG_TRACE, "n/a");
165             av_log(avr, AV_LOG_TRACE, "\n");
166             av_log(avr, AV_LOG_TRACE, "input map:  ");
167             for (ch = 0; ch < avr->in_channels; ch++)
168                 av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.input_map[ch]);
169             av_log(avr, AV_LOG_TRACE, "\n");
170         }
171 #endif
172     } else
173         avr->remap_point = REMAP_NONE;
174 
175     /* allocate buffers */
176     if (avr->in_copy_needed || avr->in_convert_needed) {
177         avr->in_buffer = ff_audio_data_alloc(FFMAX(avr->in_channels, avr->out_channels),
178                                              0, avr->internal_sample_fmt,
179                                              "in_buffer");
180         if (!avr->in_buffer) {
181             ret = AVERROR(EINVAL);
182             goto error;
183         }
184     }
185     if (avr->resample_needed) {
186         avr->resample_out_buffer = ff_audio_data_alloc(avr->out_channels,
187                                                        1024, avr->internal_sample_fmt,
188                                                        "resample_out_buffer");
189         if (!avr->resample_out_buffer) {
190             ret = AVERROR(EINVAL);
191             goto error;
192         }
193     }
194     if (avr->out_convert_needed) {
195         avr->out_buffer = ff_audio_data_alloc(avr->out_channels, 0,
196                                               avr->out_sample_fmt, "out_buffer");
197         if (!avr->out_buffer) {
198             ret = AVERROR(EINVAL);
199             goto error;
200         }
201     }
202     avr->out_fifo = av_audio_fifo_alloc(avr->out_sample_fmt, avr->out_channels,
203                                         1024);
204     if (!avr->out_fifo) {
205         ret = AVERROR(ENOMEM);
206         goto error;
207     }
208 
209     /* setup contexts */
210     if (avr->in_convert_needed) {
211         avr->ac_in = ff_audio_convert_alloc(avr, avr->internal_sample_fmt,
212                                             avr->in_sample_fmt, avr->in_channels,
213                                             avr->in_sample_rate,
214                                             avr->remap_point == REMAP_IN_CONVERT);
215         if (!avr->ac_in) {
216             ret = AVERROR(ENOMEM);
217             goto error;
218         }
219     }
220     if (avr->out_convert_needed) {
221         enum AVSampleFormat src_fmt;
222         if (avr->in_convert_needed)
223             src_fmt = avr->internal_sample_fmt;
224         else
225             src_fmt = avr->in_sample_fmt;
226         avr->ac_out = ff_audio_convert_alloc(avr, avr->out_sample_fmt, src_fmt,
227                                              avr->out_channels,
228                                              avr->out_sample_rate,
229                                              avr->remap_point == REMAP_OUT_CONVERT);
230         if (!avr->ac_out) {
231             ret = AVERROR(ENOMEM);
232             goto error;
233         }
234     }
235     if (avr->resample_needed) {
236         avr->resample = ff_audio_resample_init(avr);
237         if (!avr->resample) {
238             ret = AVERROR(ENOMEM);
239             goto error;
240         }
241     }
242     if (avr->mixing_needed) {
243         avr->am = ff_audio_mix_alloc(avr);
244         if (!avr->am) {
245             ret = AVERROR(ENOMEM);
246             goto error;
247         }
248     }
249 
250     return 0;
251 
252 error:
253     avresample_close(avr);
254     return ret;
255 }
256 
avresample_is_open(AVAudioResampleContext * avr)257 int avresample_is_open(AVAudioResampleContext *avr)
258 {
259     return !!avr->out_fifo;
260 }
261 
avresample_close(AVAudioResampleContext * avr)262 void avresample_close(AVAudioResampleContext *avr)
263 {
264     ff_audio_data_free(&avr->in_buffer);
265     ff_audio_data_free(&avr->resample_out_buffer);
266     ff_audio_data_free(&avr->out_buffer);
267     av_audio_fifo_free(avr->out_fifo);
268     avr->out_fifo = NULL;
269     ff_audio_convert_free(&avr->ac_in);
270     ff_audio_convert_free(&avr->ac_out);
271     ff_audio_resample_free(&avr->resample);
272     ff_audio_mix_free(&avr->am);
273     av_freep(&avr->mix_matrix);
274 
275     avr->use_channel_map = 0;
276 }
277 
avresample_free(AVAudioResampleContext ** avr)278 void avresample_free(AVAudioResampleContext **avr)
279 {
280     if (!*avr)
281         return;
282     avresample_close(*avr);
283     av_opt_free(*avr);
284     av_freep(avr);
285 }
286 
handle_buffered_output(AVAudioResampleContext * avr,AudioData * output,AudioData * converted)287 static int handle_buffered_output(AVAudioResampleContext *avr,
288                                   AudioData *output, AudioData *converted)
289 {
290     int ret;
291 
292     if (!output || av_audio_fifo_size(avr->out_fifo) > 0 ||
293         (converted && output->allocated_samples < converted->nb_samples)) {
294         if (converted) {
295             /* if there are any samples in the output FIFO or if the
296                user-supplied output buffer is not large enough for all samples,
297                we add to the output FIFO */
298             av_log(avr, AV_LOG_TRACE, "[FIFO] add %s to out_fifo\n", converted->name);
299             ret = ff_audio_data_add_to_fifo(avr->out_fifo, converted, 0,
300                                             converted->nb_samples);
301             if (ret < 0)
302                 return ret;
303         }
304 
305         /* if the user specified an output buffer, read samples from the output
306            FIFO to the user output */
307         if (output && output->allocated_samples > 0) {
308             av_log(avr, AV_LOG_TRACE, "[FIFO] read from out_fifo to output\n");
309             av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
310             return ff_audio_data_read_from_fifo(avr->out_fifo, output,
311                                                 output->allocated_samples);
312         }
313     } else if (converted) {
314         /* copy directly to output if it is large enough or there is not any
315            data in the output FIFO */
316         av_log(avr, AV_LOG_TRACE, "[copy] %s to output\n", converted->name);
317         output->nb_samples = 0;
318         ret = ff_audio_data_copy(output, converted,
319                                  avr->remap_point == REMAP_OUT_COPY ?
320                                  &avr->ch_map_info : NULL);
321         if (ret < 0)
322             return ret;
323         av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
324         return output->nb_samples;
325     }
326     av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
327     return 0;
328 }
329 
avresample_convert(AVAudioResampleContext * avr,uint8_t ** output,int out_plane_size,int out_samples,uint8_t * const * input,int in_plane_size,int in_samples)330 int attribute_align_arg avresample_convert(AVAudioResampleContext *avr,
331                                            uint8_t **output, int out_plane_size,
332                                            int out_samples,
333                                            uint8_t * const *input,
334                                            int in_plane_size, int in_samples)
335 {
336     AudioData input_buffer;
337     AudioData output_buffer;
338     AudioData *current_buffer;
339     int ret, direct_output;
340 
341     /* reset internal buffers */
342     if (avr->in_buffer) {
343         avr->in_buffer->nb_samples = 0;
344         ff_audio_data_set_channels(avr->in_buffer,
345                                    avr->in_buffer->allocated_channels);
346     }
347     if (avr->resample_out_buffer) {
348         avr->resample_out_buffer->nb_samples = 0;
349         ff_audio_data_set_channels(avr->resample_out_buffer,
350                                    avr->resample_out_buffer->allocated_channels);
351     }
352     if (avr->out_buffer) {
353         avr->out_buffer->nb_samples = 0;
354         ff_audio_data_set_channels(avr->out_buffer,
355                                    avr->out_buffer->allocated_channels);
356     }
357 
358     av_log(avr, AV_LOG_TRACE, "[start conversion]\n");
359 
360     /* initialize output_buffer with output data */
361     direct_output = output && av_audio_fifo_size(avr->out_fifo) == 0;
362     if (output) {
363         ret = ff_audio_data_init(&output_buffer, output, out_plane_size,
364                                  avr->out_channels, out_samples,
365                                  avr->out_sample_fmt, 0, "output");
366         if (ret < 0)
367             return ret;
368         output_buffer.nb_samples = 0;
369     }
370 
371     if (input) {
372         /* initialize input_buffer with input data */
373         ret = ff_audio_data_init(&input_buffer, input, in_plane_size,
374                                  avr->in_channels, in_samples,
375                                  avr->in_sample_fmt, 1, "input");
376         if (ret < 0)
377             return ret;
378         current_buffer = &input_buffer;
379 
380         if (avr->upmix_needed && !avr->in_convert_needed && !avr->resample_needed &&
381             !avr->out_convert_needed && direct_output && out_samples >= in_samples) {
382             /* in some rare cases we can copy input to output and upmix
383                directly in the output buffer */
384             av_log(avr, AV_LOG_TRACE, "[copy] %s to output\n", current_buffer->name);
385             ret = ff_audio_data_copy(&output_buffer, current_buffer,
386                                      avr->remap_point == REMAP_OUT_COPY ?
387                                      &avr->ch_map_info : NULL);
388             if (ret < 0)
389                 return ret;
390             current_buffer = &output_buffer;
391         } else if (avr->remap_point == REMAP_OUT_COPY &&
392                    (!direct_output || out_samples < in_samples)) {
393             /* if remapping channels during output copy, we may need to
394              * use an intermediate buffer in order to remap before adding
395              * samples to the output fifo */
396             av_log(avr, AV_LOG_TRACE, "[copy] %s to out_buffer\n", current_buffer->name);
397             ret = ff_audio_data_copy(avr->out_buffer, current_buffer,
398                                      &avr->ch_map_info);
399             if (ret < 0)
400                 return ret;
401             current_buffer = avr->out_buffer;
402         } else if (avr->in_copy_needed || avr->in_convert_needed) {
403             /* if needed, copy or convert input to in_buffer, and downmix if
404                applicable */
405             if (avr->in_convert_needed) {
406                 ret = ff_audio_data_realloc(avr->in_buffer,
407                                             current_buffer->nb_samples);
408                 if (ret < 0)
409                     return ret;
410                 av_log(avr, AV_LOG_TRACE, "[convert] %s to in_buffer\n", current_buffer->name);
411                 ret = ff_audio_convert(avr->ac_in, avr->in_buffer,
412                                        current_buffer);
413                 if (ret < 0)
414                     return ret;
415             } else {
416                 av_log(avr, AV_LOG_TRACE, "[copy] %s to in_buffer\n", current_buffer->name);
417                 ret = ff_audio_data_copy(avr->in_buffer, current_buffer,
418                                          avr->remap_point == REMAP_IN_COPY ?
419                                          &avr->ch_map_info : NULL);
420                 if (ret < 0)
421                     return ret;
422             }
423             ff_audio_data_set_channels(avr->in_buffer, avr->in_channels);
424             if (avr->downmix_needed) {
425                 av_log(avr, AV_LOG_TRACE, "[downmix] in_buffer\n");
426                 ret = ff_audio_mix(avr->am, avr->in_buffer);
427                 if (ret < 0)
428                     return ret;
429             }
430             current_buffer = avr->in_buffer;
431         }
432     } else {
433         /* flush resampling buffer and/or output FIFO if input is NULL */
434         if (!avr->resample_needed)
435             return handle_buffered_output(avr, output ? &output_buffer : NULL,
436                                           NULL);
437         current_buffer = NULL;
438     }
439 
440     if (avr->resample_needed) {
441         AudioData *resample_out;
442 
443         if (!avr->out_convert_needed && direct_output && out_samples > 0)
444             resample_out = &output_buffer;
445         else
446             resample_out = avr->resample_out_buffer;
447         av_log(avr, AV_LOG_TRACE, "[resample] %s to %s\n",
448                 current_buffer ? current_buffer->name : "null",
449                 resample_out->name);
450         ret = ff_audio_resample(avr->resample, resample_out,
451                                 current_buffer);
452         if (ret < 0)
453             return ret;
454 
455         /* if resampling did not produce any samples, just return 0 */
456         if (resample_out->nb_samples == 0) {
457             av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
458             return 0;
459         }
460 
461         current_buffer = resample_out;
462     }
463 
464     if (avr->upmix_needed) {
465         av_log(avr, AV_LOG_TRACE, "[upmix] %s\n", current_buffer->name);
466         ret = ff_audio_mix(avr->am, current_buffer);
467         if (ret < 0)
468             return ret;
469     }
470 
471     /* if we resampled or upmixed directly to output, return here */
472     if (current_buffer == &output_buffer) {
473         av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
474         return current_buffer->nb_samples;
475     }
476 
477     if (avr->out_convert_needed) {
478         if (direct_output && out_samples >= current_buffer->nb_samples) {
479             /* convert directly to output */
480             av_log(avr, AV_LOG_TRACE, "[convert] %s to output\n", current_buffer->name);
481             ret = ff_audio_convert(avr->ac_out, &output_buffer, current_buffer);
482             if (ret < 0)
483                 return ret;
484 
485             av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
486             return output_buffer.nb_samples;
487         } else {
488             ret = ff_audio_data_realloc(avr->out_buffer,
489                                         current_buffer->nb_samples);
490             if (ret < 0)
491                 return ret;
492             av_log(avr, AV_LOG_TRACE, "[convert] %s to out_buffer\n", current_buffer->name);
493             ret = ff_audio_convert(avr->ac_out, avr->out_buffer,
494                                    current_buffer);
495             if (ret < 0)
496                 return ret;
497             current_buffer = avr->out_buffer;
498         }
499     }
500 
501     return handle_buffered_output(avr, output ? &output_buffer : NULL,
502                                   current_buffer);
503 }
504 
avresample_config(AVAudioResampleContext * avr,AVFrame * out,AVFrame * in)505 int avresample_config(AVAudioResampleContext *avr, AVFrame *out, AVFrame *in)
506 {
507     if (avresample_is_open(avr)) {
508         avresample_close(avr);
509     }
510 
511     if (in) {
512         avr->in_channel_layout  = in->channel_layout;
513         avr->in_sample_rate     = in->sample_rate;
514         avr->in_sample_fmt      = in->format;
515     }
516 
517     if (out) {
518         avr->out_channel_layout = out->channel_layout;
519         avr->out_sample_rate    = out->sample_rate;
520         avr->out_sample_fmt     = out->format;
521     }
522 
523     return 0;
524 }
525 
config_changed(AVAudioResampleContext * avr,AVFrame * out,AVFrame * in)526 static int config_changed(AVAudioResampleContext *avr,
527                           AVFrame *out, AVFrame *in)
528 {
529     int ret = 0;
530 
531     if (in) {
532         if (avr->in_channel_layout != in->channel_layout ||
533             avr->in_sample_rate    != in->sample_rate ||
534             avr->in_sample_fmt     != in->format) {
535             ret |= AVERROR_INPUT_CHANGED;
536         }
537     }
538 
539     if (out) {
540         if (avr->out_channel_layout != out->channel_layout ||
541             avr->out_sample_rate    != out->sample_rate ||
542             avr->out_sample_fmt     != out->format) {
543             ret |= AVERROR_OUTPUT_CHANGED;
544         }
545     }
546 
547     return ret;
548 }
549 
convert_frame(AVAudioResampleContext * avr,AVFrame * out,AVFrame * in)550 static inline int convert_frame(AVAudioResampleContext *avr,
551                                 AVFrame *out, AVFrame *in)
552 {
553     int ret;
554     uint8_t **out_data = NULL, **in_data = NULL;
555     int out_linesize = 0, in_linesize = 0;
556     int out_nb_samples = 0, in_nb_samples = 0;
557 
558     if (out) {
559         out_data       = out->extended_data;
560         out_linesize   = out->linesize[0];
561         out_nb_samples = out->nb_samples;
562     }
563 
564     if (in) {
565         in_data       = in->extended_data;
566         in_linesize   = in->linesize[0];
567         in_nb_samples = in->nb_samples;
568     }
569 
570     ret = avresample_convert(avr, out_data, out_linesize,
571                              out_nb_samples,
572                              in_data, in_linesize,
573                              in_nb_samples);
574 
575     if (ret < 0) {
576         if (out)
577             out->nb_samples = 0;
578         return ret;
579     }
580 
581     if (out)
582         out->nb_samples = ret;
583 
584     return 0;
585 }
586 
available_samples(AVFrame * out)587 static inline int available_samples(AVFrame *out)
588 {
589     int samples;
590     int bytes_per_sample = av_get_bytes_per_sample(out->format);
591     if (!bytes_per_sample)
592         return AVERROR(EINVAL);
593 
594     samples = out->linesize[0] / bytes_per_sample;
595     if (av_sample_fmt_is_planar(out->format)) {
596         return samples;
597     } else {
598         int channels = av_get_channel_layout_nb_channels(out->channel_layout);
599         return samples / channels;
600     }
601 }
602 
avresample_convert_frame(AVAudioResampleContext * avr,AVFrame * out,AVFrame * in)603 int avresample_convert_frame(AVAudioResampleContext *avr,
604                              AVFrame *out, AVFrame *in)
605 {
606     int ret, setup = 0;
607 
608     if (!avresample_is_open(avr)) {
609         if ((ret = avresample_config(avr, out, in)) < 0)
610             return ret;
611         if ((ret = avresample_open(avr)) < 0)
612             return ret;
613         setup = 1;
614     } else {
615         // return as is or reconfigure for input changes?
616         if ((ret = config_changed(avr, out, in)))
617             return ret;
618     }
619 
620     if (out) {
621         if (!out->linesize[0]) {
622             out->nb_samples = avresample_get_out_samples(avr, in->nb_samples);
623             if ((ret = av_frame_get_buffer(out, 0)) < 0) {
624                 if (setup)
625                     avresample_close(avr);
626                 return ret;
627             }
628         } else {
629             if (!out->nb_samples)
630                 out->nb_samples = available_samples(out);
631         }
632     }
633 
634     return convert_frame(avr, out, in);
635 }
636 
avresample_get_matrix(AVAudioResampleContext * avr,double * matrix,int stride)637 int avresample_get_matrix(AVAudioResampleContext *avr, double *matrix,
638                           int stride)
639 {
640     int in_channels, out_channels, i, o;
641 
642     if (avr->am)
643         return ff_audio_mix_get_matrix(avr->am, matrix, stride);
644 
645     in_channels  = av_get_channel_layout_nb_channels(avr->in_channel_layout);
646     out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);
647 
648     if ( in_channels <= 0 ||  in_channels > AVRESAMPLE_MAX_CHANNELS ||
649         out_channels <= 0 || out_channels > AVRESAMPLE_MAX_CHANNELS) {
650         av_log(avr, AV_LOG_ERROR, "Invalid channel layouts\n");
651         return AVERROR(EINVAL);
652     }
653 
654     if (!avr->mix_matrix) {
655         av_log(avr, AV_LOG_ERROR, "matrix is not set\n");
656         return AVERROR(EINVAL);
657     }
658 
659     for (o = 0; o < out_channels; o++)
660         for (i = 0; i < in_channels; i++)
661             matrix[o * stride + i] = avr->mix_matrix[o * in_channels + i];
662 
663     return 0;
664 }
665 
avresample_set_matrix(AVAudioResampleContext * avr,const double * matrix,int stride)666 int avresample_set_matrix(AVAudioResampleContext *avr, const double *matrix,
667                           int stride)
668 {
669     int in_channels, out_channels, i, o;
670 
671     if (avr->am)
672         return ff_audio_mix_set_matrix(avr->am, matrix, stride);
673 
674     in_channels  = av_get_channel_layout_nb_channels(avr->in_channel_layout);
675     out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);
676 
677     if ( in_channels <= 0 ||  in_channels > AVRESAMPLE_MAX_CHANNELS ||
678         out_channels <= 0 || out_channels > AVRESAMPLE_MAX_CHANNELS) {
679         av_log(avr, AV_LOG_ERROR, "Invalid channel layouts\n");
680         return AVERROR(EINVAL);
681     }
682 
683     if (avr->mix_matrix)
684         av_freep(&avr->mix_matrix);
685     avr->mix_matrix = av_malloc(in_channels * out_channels *
686                                 sizeof(*avr->mix_matrix));
687     if (!avr->mix_matrix)
688         return AVERROR(ENOMEM);
689 
690     for (o = 0; o < out_channels; o++)
691         for (i = 0; i < in_channels; i++)
692             avr->mix_matrix[o * in_channels + i] = matrix[o * stride + i];
693 
694     return 0;
695 }
696 
avresample_set_channel_mapping(AVAudioResampleContext * avr,const int * channel_map)697 int avresample_set_channel_mapping(AVAudioResampleContext *avr,
698                                    const int *channel_map)
699 {
700     ChannelMapInfo *info = &avr->ch_map_info;
701     int in_channels, ch, i;
702 
703     in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);
704     if (in_channels <= 0 ||  in_channels > AVRESAMPLE_MAX_CHANNELS) {
705         av_log(avr, AV_LOG_ERROR, "Invalid input channel layout\n");
706         return AVERROR(EINVAL);
707     }
708 
709     memset(info, 0, sizeof(*info));
710     memset(info->input_map, -1, sizeof(info->input_map));
711 
712     for (ch = 0; ch < in_channels; ch++) {
713         if (channel_map[ch] >= in_channels) {
714             av_log(avr, AV_LOG_ERROR, "Invalid channel map\n");
715             return AVERROR(EINVAL);
716         }
717         if (channel_map[ch] < 0) {
718             info->channel_zero[ch] =  1;
719             info->channel_map[ch]  = -1;
720             info->do_zero          =  1;
721         } else if (info->input_map[channel_map[ch]] >= 0) {
722             info->channel_copy[ch] = info->input_map[channel_map[ch]];
723             info->channel_map[ch]  = -1;
724             info->do_copy          =  1;
725         } else {
726             info->channel_map[ch]            = channel_map[ch];
727             info->input_map[channel_map[ch]] = ch;
728             info->do_remap                   =  1;
729         }
730     }
731     /* Fill-in unmapped input channels with unmapped output channels.
732        This is used when remapping during conversion from interleaved to
733        planar format. */
734     for (ch = 0, i = 0; ch < in_channels && i < in_channels; ch++, i++) {
735         while (ch < in_channels && info->input_map[ch] >= 0)
736             ch++;
737         while (i < in_channels && info->channel_map[i] >= 0)
738             i++;
739         if (ch >= in_channels || i >= in_channels)
740             break;
741         info->input_map[ch] = i;
742     }
743 
744     avr->use_channel_map = 1;
745     return 0;
746 }
747 
avresample_available(AVAudioResampleContext * avr)748 int avresample_available(AVAudioResampleContext *avr)
749 {
750     return av_audio_fifo_size(avr->out_fifo);
751 }
752 
avresample_get_out_samples(AVAudioResampleContext * avr,int in_nb_samples)753 int avresample_get_out_samples(AVAudioResampleContext *avr, int in_nb_samples)
754 {
755     int64_t samples = avresample_get_delay(avr) + (int64_t)in_nb_samples;
756 
757     if (avr->resample_needed) {
758         samples = av_rescale_rnd(samples,
759                                  avr->out_sample_rate,
760                                  avr->in_sample_rate,
761                                  AV_ROUND_UP);
762     }
763 
764     samples += avresample_available(avr);
765 
766     if (samples > INT_MAX)
767         return AVERROR(EINVAL);
768 
769     return samples;
770 }
771 
avresample_read(AVAudioResampleContext * avr,uint8_t ** output,int nb_samples)772 int avresample_read(AVAudioResampleContext *avr, uint8_t **output, int nb_samples)
773 {
774     if (!output)
775         return av_audio_fifo_drain(avr->out_fifo, nb_samples);
776     return av_audio_fifo_read(avr->out_fifo, (void**)output, nb_samples);
777 }
778 
avresample_version(void)779 unsigned avresample_version(void)
780 {
781     return LIBAVRESAMPLE_VERSION_INT;
782 }
783 
avresample_license(void)784 const char *avresample_license(void)
785 {
786 #define LICENSE_PREFIX "libavresample license: "
787     return LICENSE_PREFIX FFMPEG_LICENSE + sizeof(LICENSE_PREFIX) - 1;
788 }
789 
avresample_configuration(void)790 const char *avresample_configuration(void)
791 {
792     return FFMPEG_CONFIGURATION;
793 }
794