FFmpeg  2.1.1
af_aresample.c
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1 /*
2  * Copyright (c) 2011 Stefano Sabatini
3  * Copyright (c) 2011 Mina Nagy Zaki
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 /**
23  * @file
24  * resampling audio filter
25  */
26 
27 #include "libavutil/avstring.h"
28 #include "libavutil/channel_layout.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/samplefmt.h"
31 #include "libavutil/avassert.h"
32 #include "libswresample/swresample.h"
33 #include "avfilter.h"
34 #include "audio.h"
35 #include "internal.h"
36 
37 typedef struct {
38  const AVClass *class;
40  double ratio;
41  struct SwrContext *swr;
42  int64_t next_pts;
45 
47 {
48  AResampleContext *aresample = ctx->priv;
49  int ret = 0;
50 
51  aresample->next_pts = AV_NOPTS_VALUE;
52  aresample->swr = swr_alloc();
53  if (!aresample->swr) {
54  ret = AVERROR(ENOMEM);
55  goto end;
56  }
57 
58  if (opts) {
59  AVDictionaryEntry *e = NULL;
60 
61  while ((e = av_dict_get(*opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
62  if ((ret = av_opt_set(aresample->swr, e->key, e->value, 0)) < 0)
63  goto end;
64  }
65  av_dict_free(opts);
66  }
67  if (aresample->sample_rate_arg > 0)
68  av_opt_set_int(aresample->swr, "osr", aresample->sample_rate_arg, 0);
69 end:
70  return ret;
71 }
72 
73 static av_cold void uninit(AVFilterContext *ctx)
74 {
75  AResampleContext *aresample = ctx->priv;
76  swr_free(&aresample->swr);
77 }
78 
80 {
81  AResampleContext *aresample = ctx->priv;
82  int out_rate = av_get_int(aresample->swr, "osr", NULL);
83  uint64_t out_layout = av_get_int(aresample->swr, "ocl", NULL);
84  enum AVSampleFormat out_format = av_get_int(aresample->swr, "osf", NULL);
85 
86  AVFilterLink *inlink = ctx->inputs[0];
87  AVFilterLink *outlink = ctx->outputs[0];
88 
90  AVFilterFormats *out_formats;
91  AVFilterFormats *in_samplerates = ff_all_samplerates();
92  AVFilterFormats *out_samplerates;
94  AVFilterChannelLayouts *out_layouts;
95 
96  ff_formats_ref (in_formats, &inlink->out_formats);
97  ff_formats_ref (in_samplerates, &inlink->out_samplerates);
98  ff_channel_layouts_ref(in_layouts, &inlink->out_channel_layouts);
99 
100  if(out_rate > 0) {
101  out_samplerates = ff_make_format_list((int[]){ out_rate, -1 });
102  } else {
103  out_samplerates = ff_all_samplerates();
104  }
105  ff_formats_ref(out_samplerates, &outlink->in_samplerates);
106 
107  if(out_format != AV_SAMPLE_FMT_NONE) {
108  out_formats = ff_make_format_list((int[]){ out_format, -1 });
109  } else
110  out_formats = ff_all_formats(AVMEDIA_TYPE_AUDIO);
111  ff_formats_ref(out_formats, &outlink->in_formats);
112 
113  if(out_layout) {
114  out_layouts = avfilter_make_format64_list((int64_t[]){ out_layout, -1 });
115  } else
116  out_layouts = ff_all_channel_counts();
117  ff_channel_layouts_ref(out_layouts, &outlink->in_channel_layouts);
118 
119  return 0;
120 }
121 
122 
123 static int config_output(AVFilterLink *outlink)
124 {
125  int ret;
126  AVFilterContext *ctx = outlink->src;
127  AVFilterLink *inlink = ctx->inputs[0];
128  AResampleContext *aresample = ctx->priv;
129  int out_rate;
130  uint64_t out_layout;
131  enum AVSampleFormat out_format;
132  char inchl_buf[128], outchl_buf[128];
133 
134  aresample->swr = swr_alloc_set_opts(aresample->swr,
135  outlink->channel_layout, outlink->format, outlink->sample_rate,
136  inlink->channel_layout, inlink->format, inlink->sample_rate,
137  0, ctx);
138  if (!aresample->swr)
139  return AVERROR(ENOMEM);
140  if (!inlink->channel_layout)
141  av_opt_set_int(aresample->swr, "ich", inlink->channels, 0);
142  if (!outlink->channel_layout)
143  av_opt_set_int(aresample->swr, "och", outlink->channels, 0);
144 
145  ret = swr_init(aresample->swr);
146  if (ret < 0)
147  return ret;
148 
149  out_rate = av_get_int(aresample->swr, "osr", NULL);
150  out_layout = av_get_int(aresample->swr, "ocl", NULL);
151  out_format = av_get_int(aresample->swr, "osf", NULL);
152  outlink->time_base = (AVRational) {1, out_rate};
153 
154  av_assert0(outlink->sample_rate == out_rate);
155  av_assert0(outlink->channel_layout == out_layout || !outlink->channel_layout);
156  av_assert0(outlink->format == out_format);
157 
158  aresample->ratio = (double)outlink->sample_rate / inlink->sample_rate;
159 
160  av_get_channel_layout_string(inchl_buf, sizeof(inchl_buf), inlink ->channels, inlink ->channel_layout);
161  av_get_channel_layout_string(outchl_buf, sizeof(outchl_buf), outlink->channels, outlink->channel_layout);
162 
163  av_log(ctx, AV_LOG_VERBOSE, "ch:%d chl:%s fmt:%s r:%dHz -> ch:%d chl:%s fmt:%s r:%dHz\n",
164  inlink ->channels, inchl_buf, av_get_sample_fmt_name(inlink->format), inlink->sample_rate,
165  outlink->channels, outchl_buf, av_get_sample_fmt_name(outlink->format), outlink->sample_rate);
166  return 0;
167 }
168 
169 static int filter_frame(AVFilterLink *inlink, AVFrame *insamplesref)
170 {
171  AResampleContext *aresample = inlink->dst->priv;
172  const int n_in = insamplesref->nb_samples;
173  int n_out = n_in * aresample->ratio * 2 + 256;
174  AVFilterLink *const outlink = inlink->dst->outputs[0];
175  AVFrame *outsamplesref = ff_get_audio_buffer(outlink, n_out);
176  int ret;
177 
178  if(!outsamplesref)
179  return AVERROR(ENOMEM);
180 
181  av_frame_copy_props(outsamplesref, insamplesref);
182  outsamplesref->format = outlink->format;
183  av_frame_set_channels(outsamplesref, outlink->channels);
184  outsamplesref->channel_layout = outlink->channel_layout;
185  outsamplesref->sample_rate = outlink->sample_rate;
186 
187  if(insamplesref->pts != AV_NOPTS_VALUE) {
188  int64_t inpts = av_rescale(insamplesref->pts, inlink->time_base.num * (int64_t)outlink->sample_rate * inlink->sample_rate, inlink->time_base.den);
189  int64_t outpts= swr_next_pts(aresample->swr, inpts);
190  aresample->next_pts =
191  outsamplesref->pts = ROUNDED_DIV(outpts, inlink->sample_rate);
192  } else {
193  outsamplesref->pts = AV_NOPTS_VALUE;
194  }
195  n_out = swr_convert(aresample->swr, outsamplesref->extended_data, n_out,
196  (void *)insamplesref->extended_data, n_in);
197  if (n_out <= 0) {
198  av_frame_free(&outsamplesref);
199  av_frame_free(&insamplesref);
200  return 0;
201  }
202 
203  outsamplesref->nb_samples = n_out;
204 
205  ret = ff_filter_frame(outlink, outsamplesref);
206  aresample->req_fullfilled= 1;
207  av_frame_free(&insamplesref);
208  return ret;
209 }
210 
211 static int request_frame(AVFilterLink *outlink)
212 {
213  AVFilterContext *ctx = outlink->src;
214  AResampleContext *aresample = ctx->priv;
215  AVFilterLink *const inlink = outlink->src->inputs[0];
216  int ret;
217 
218  aresample->req_fullfilled = 0;
219  do{
220  ret = ff_request_frame(ctx->inputs[0]);
221  }while(!aresample->req_fullfilled && ret>=0);
222 
223  if (ret == AVERROR_EOF) {
224  AVFrame *outsamplesref;
225  int n_out = 4096;
226 
227  outsamplesref = ff_get_audio_buffer(outlink, n_out);
228  if (!outsamplesref)
229  return AVERROR(ENOMEM);
230  n_out = swr_convert(aresample->swr, outsamplesref->extended_data, n_out, 0, 0);
231  if (n_out <= 0) {
232  av_frame_free(&outsamplesref);
233  return (n_out == 0) ? AVERROR_EOF : n_out;
234  }
235 
236  outsamplesref->sample_rate = outlink->sample_rate;
237  outsamplesref->nb_samples = n_out;
238 #if 0
239  outsamplesref->pts = aresample->next_pts;
240  if(aresample->next_pts != AV_NOPTS_VALUE)
241  aresample->next_pts += av_rescale_q(n_out, (AVRational){1 ,outlink->sample_rate}, outlink->time_base);
242 #else
243  outsamplesref->pts = swr_next_pts(aresample->swr, INT64_MIN);
244  outsamplesref->pts = ROUNDED_DIV(outsamplesref->pts, inlink->sample_rate);
245 #endif
246 
247  return ff_filter_frame(outlink, outsamplesref);
248  }
249  return ret;
250 }
251 
252 static const AVClass *resample_child_class_next(const AVClass *prev)
253 {
254  return prev ? NULL : swr_get_class();
255 }
256 
257 static void *resample_child_next(void *obj, void *prev)
258 {
259  AResampleContext *s = obj;
260  return prev ? NULL : s->swr;
261 }
262 
263 #define OFFSET(x) offsetof(AResampleContext, x)
264 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
265 
266 static const AVOption options[] = {
267  {"sample_rate", NULL, OFFSET(sample_rate_arg), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS },
268  {NULL}
269 };
270 
271 static const AVClass aresample_class = {
272  .class_name = "aresample",
273  .item_name = av_default_item_name,
274  .option = options,
275  .version = LIBAVUTIL_VERSION_INT,
276  .child_class_next = resample_child_class_next,
278 };
279 
280 static const AVFilterPad aresample_inputs[] = {
281  {
282  .name = "default",
283  .type = AVMEDIA_TYPE_AUDIO,
284  .filter_frame = filter_frame,
285  },
286  { NULL }
287 };
288 
289 static const AVFilterPad aresample_outputs[] = {
290  {
291  .name = "default",
292  .config_props = config_output,
293  .request_frame = request_frame,
294  .type = AVMEDIA_TYPE_AUDIO,
295  },
296  { NULL }
297 };
298 
300  .name = "aresample",
301  .description = NULL_IF_CONFIG_SMALL("Resample audio data."),
302  .init_dict = init_dict,
303  .uninit = uninit,
304  .query_formats = query_formats,
305  .priv_size = sizeof(AResampleContext),
306  .priv_class = &aresample_class,
307  .inputs = aresample_inputs,
308  .outputs = aresample_outputs,
309 };
void *(* child_next)(void *obj, void *prev)
Return next AVOptions-enabled child or NULL.
Definition: log.h:96
const char * s
Definition: avisynth_c.h:668
char * key
Definition: dict.h:81
This structure describes decoded (raw) audio or video data.
Definition: frame.h:96
const char * av_get_sample_fmt_name(enum AVSampleFormat sample_fmt)
Return the name of sample_fmt, or NULL if sample_fmt is not recognized.
Definition: samplefmt.c:47
AVOption.
Definition: opt.h:253
static const AVFilterPad aresample_inputs[]
Definition: af_aresample.c:280
const char * name
Filter name.
Definition: avfilter.h:468
void * priv
private data for use by the filter
Definition: avfilter.h:648
static const AVFilterPad outputs[]
Definition: af_ashowinfo.c:111
#define LIBAVUTIL_VERSION_INT
Definition: avcodec.h:820
struct SwrContext * swr_alloc_set_opts(struct SwrContext *s, int64_t out_ch_layout, enum AVSampleFormat out_sample_fmt, int out_sample_rate, int64_t in_ch_layout, enum AVSampleFormat in_sample_fmt, int in_sample_rate, int log_offset, void *log_ctx)
Allocate SwrContext if needed and set/reset common parameters.
Definition: swresample.c:187
AVDictionaryEntry * av_dict_get(AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:39
int num
numerator
Definition: rational.h:44
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:140
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
int64_t swr_next_pts(struct SwrContext *s, int64_t pts)
Convert the next timestamp from input to output timestamps are in 1/(in_sample_rate * out_sample_rate...
Definition: swresample.c:902
struct SwrContext * swr_alloc(void)
Allocate SwrContext.
Definition: swresample.c:178
#define av_cold
Definition: avcodec.h:653
void av_frame_set_channels(AVFrame *frame, int val)
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:294
const char * name
Pad name.
Definition: internal.h:66
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1118
const char * av_default_item_name(void *ctx)
Return the context name.
Definition: log.c:145
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:55
#define FLAGS
Definition: af_aresample.c:264
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only &quot;metadata&quot; fields from src to dst.
Definition: frame.c:446
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:67
AVFilter avfilter_af_aresample
Definition: af_aresample.c:299
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:182
void ff_channel_layouts_ref(AVFilterChannelLayouts *f, AVFilterChannelLayouts **ref)
Add *ref as a new reference to f.
Definition: formats.c:413
int swr_convert(struct SwrContext *s, uint8_t **out, int out_count, const uint8_t **in, int in_count)
Convert audio.
#define AV_LOG_VERBOSE
Detailed information.
Definition: avcodec.h:4163
const OptionDef options[]
Definition: ffserver.c:4682
AVFilterFormats * ff_all_formats(enum AVMediaType type)
Return a list of all formats supported by FFmpeg for the given media type.
Definition: formats.c:343
A filter pad used for either input or output.
Definition: internal.h:60
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:130
static void * resample_child_next(void *obj, void *prev)
Definition: af_aresample.c:257
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
Definition: audio.c:70
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
void av_dict_free(AVDictionary **m)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:162
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
Definition: opt.c:426
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:123
uint64_t channel_layout
Channel layout of the audio data.
Definition: frame.h:354
int64_t av_rescale(int64_t a, int64_t b, int64_t c) av_const
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:118
ret
Definition: avfilter.c:961
static const AVClass aresample_class
Definition: af_aresample.c:271
int64_t av_get_int(void *obj, const char *name, const AVOption **o_out)
Definition: opt.c:730
static av_cold int init_dict(AVFilterContext *ctx, AVDictionary **opts)
Definition: af_aresample.c:46
char * value
Definition: dict.h:82
A list of supported channel layouts.
Definition: formats.h:85
Main libavfilter public API header.
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_aresample.c:73
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:642
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:157
AVSampleFormat
Audio Sample Formats.
Definition: samplefmt.h:49
int64_t outpts
output PTS
void ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
Add *ref as a new reference to formats.
Definition: formats.c:418
AVFilterChannelLayouts * avfilter_make_format64_list(const int64_t *fmts)
Definition: formats.c:303
static const AVFilterPad aresample_outputs[]
Definition: af_aresample.c:289
void swr_free(struct SwrContext **s)
Free the given SwrContext and set the pointer to NULL.
Definition: swresample.c:221
Describe the class of an AVClass context structure.
Definition: log.h:50
int sample_rate
Sample rate of the audio data.
Definition: frame.h:349
Filter definition.
Definition: avfilter.h:464
static const AVFilterPad inputs[]
Definition: af_ashowinfo.c:102
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:635
rational number numerator/denominator
Definition: rational.h:43
struct SwrContext * swr
Definition: af_aresample.c:41
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:382
#define ROUNDED_DIV(a, b)
Definition: avcodec.h:914
#define AVERROR_EOF
static int filter_frame(AVFilterLink *inlink, AVFrame *insamplesref)
Definition: af_aresample.c:169
static const AVClass * resample_child_class_next(const AVClass *prev)
Definition: af_aresample.c:252
int den
denominator
Definition: rational.h:45
#define OFFSET(x)
Definition: af_aresample.c:263
A list of supported formats for one end of a filter link.
Definition: formats.h:64
#define AVERROR(e)
An instance of a filter.
Definition: avfilter.h:627
#define AV_DICT_IGNORE_SUFFIX
Definition: dict.h:68
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:335
internal API functions
AVFilterChannelLayouts * ff_all_channel_counts(void)
Construct an AVFilterChannelLayouts coding for any channel layout, with known or unknown disposition...
Definition: formats.c:397
static int query_formats(AVFilterContext *ctx)
Definition: af_aresample.c:79
const AVClass * swr_get_class(void)
Get the AVClass for swrContext.
Definition: swresample.c:173
int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
Definition: opt.c:255
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:150
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avcodec.h:2278
static int request_frame(AVFilterLink *outlink)
Definition: af_aresample.c:211
int swr_init(struct SwrContext *s)
Initialize context after user parameters have been set.
Definition: swresample.c:243
static int config_output(AVFilterLink *outlink)
Definition: af_aresample.c:123
void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout)
Return a description of a channel layout.