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af_adelay.c
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1 /*
2  * Copyright (c) 2013 Paul B Mahol
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/avstring.h"
22 #include "libavutil/opt.h"
23 #include "libavutil/samplefmt.h"
24 #include "avfilter.h"
25 #include "audio.h"
26 #include "internal.h"
27 
28 typedef struct ChanDelay {
29  int delay;
30  unsigned delay_index;
31  unsigned index;
33 } ChanDelay;
34 
35 typedef struct AudioDelayContext {
36  const AVClass *class;
37  char *delays;
39  int nb_delays;
41  unsigned max_delay;
42  int64_t next_pts;
43 
44  void (*delay_channel)(ChanDelay *d, int nb_samples,
45  const uint8_t *src, uint8_t *dst);
47 
48 #define OFFSET(x) offsetof(AudioDelayContext, x)
49 #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
50 
51 static const AVOption adelay_options[] = {
52  { "delays", "set list of delays for each channel", OFFSET(delays), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, A },
53  { NULL }
54 };
55 
56 AVFILTER_DEFINE_CLASS(adelay);
57 
59 {
62  static const enum AVSampleFormat sample_fmts[] = {
66  };
67 
68  layouts = ff_all_channel_layouts();
69  if (!layouts)
70  return AVERROR(ENOMEM);
71  ff_set_common_channel_layouts(ctx, layouts);
72 
73  formats = ff_make_format_list(sample_fmts);
74  if (!formats)
75  return AVERROR(ENOMEM);
76  ff_set_common_formats(ctx, formats);
77 
78  formats = ff_all_samplerates();
79  if (!formats)
80  return AVERROR(ENOMEM);
81  ff_set_common_samplerates(ctx, formats);
82 
83  return 0;
84 }
85 
86 #define DELAY(name, type, fill) \
87 static void delay_channel_## name ##p(ChanDelay *d, int nb_samples, \
88  const uint8_t *ssrc, uint8_t *ddst) \
89 { \
90  const type *src = (type *)ssrc; \
91  type *dst = (type *)ddst; \
92  type *samples = (type *)d->samples; \
93  \
94  while (nb_samples) { \
95  if (d->delay_index < d->delay) { \
96  const int len = FFMIN(nb_samples, d->delay - d->delay_index); \
97  \
98  memcpy(&samples[d->delay_index], src, len * sizeof(type)); \
99  memset(dst, fill, len * sizeof(type)); \
100  d->delay_index += len; \
101  src += len; \
102  dst += len; \
103  nb_samples -= len; \
104  } else { \
105  *dst = samples[d->index]; \
106  samples[d->index] = *src; \
107  nb_samples--; \
108  d->index++; \
109  src++, dst++; \
110  d->index = d->index >= d->delay ? 0 : d->index; \
111  } \
112  } \
113 }
114 
115 DELAY(u8, uint8_t, 0x80)
116 DELAY(s16, int16_t, 0)
117 DELAY(s32, int32_t, 0)
118 DELAY(flt, float, 0)
119 DELAY(dbl, double, 0)
120 
121 static int config_input(AVFilterLink *inlink)
122 {
123  AVFilterContext *ctx = inlink->dst;
124  AudioDelayContext *s = ctx->priv;
125  char *p, *arg, *saveptr = NULL;
126  int i;
127 
128  s->chandelay = av_calloc(inlink->channels, sizeof(*s->chandelay));
129  if (!s->chandelay)
130  return AVERROR(ENOMEM);
131  s->nb_delays = inlink->channels;
132  s->block_align = av_get_bytes_per_sample(inlink->format);
133 
134  p = s->delays;
135  for (i = 0; i < s->nb_delays; i++) {
136  ChanDelay *d = &s->chandelay[i];
137  float delay;
138 
139  if (!(arg = av_strtok(p, "|", &saveptr)))
140  break;
141 
142  p = NULL;
143  sscanf(arg, "%f", &delay);
144 
145  d->delay = delay * inlink->sample_rate / 1000.0;
146  if (d->delay < 0) {
147  av_log(ctx, AV_LOG_ERROR, "Delay must be non negative number.\n");
148  return AVERROR(EINVAL);
149  }
150  }
151 
152  for (i = 0; i < s->nb_delays; i++) {
153  ChanDelay *d = &s->chandelay[i];
154 
155  if (!d->delay)
156  continue;
157 
159  if (!d->samples)
160  return AVERROR(ENOMEM);
161 
162  s->max_delay = FFMAX(s->max_delay, d->delay);
163  }
164 
165  if (!s->max_delay) {
166  av_log(ctx, AV_LOG_ERROR, "At least one delay >0 must be specified.\n");
167  return AVERROR(EINVAL);
168  }
169 
170  switch (inlink->format) {
171  case AV_SAMPLE_FMT_U8P : s->delay_channel = delay_channel_u8p ; break;
172  case AV_SAMPLE_FMT_S16P: s->delay_channel = delay_channel_s16p; break;
173  case AV_SAMPLE_FMT_S32P: s->delay_channel = delay_channel_s32p; break;
174  case AV_SAMPLE_FMT_FLTP: s->delay_channel = delay_channel_fltp; break;
175  case AV_SAMPLE_FMT_DBLP: s->delay_channel = delay_channel_dblp; break;
176  }
177 
178  return 0;
179 }
180 
181 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
182 {
183  AVFilterContext *ctx = inlink->dst;
184  AudioDelayContext *s = ctx->priv;
185  AVFrame *out_frame;
186  int i;
187 
188  if (ctx->is_disabled || !s->delays)
189  return ff_filter_frame(ctx->outputs[0], frame);
190 
191  out_frame = ff_get_audio_buffer(inlink, frame->nb_samples);
192  if (!out_frame)
193  return AVERROR(ENOMEM);
194  av_frame_copy_props(out_frame, frame);
195 
196  for (i = 0; i < s->nb_delays; i++) {
197  ChanDelay *d = &s->chandelay[i];
198  const uint8_t *src = frame->extended_data[i];
199  uint8_t *dst = out_frame->extended_data[i];
200 
201  if (!d->delay)
202  memcpy(dst, src, frame->nb_samples * s->block_align);
203  else
204  s->delay_channel(d, frame->nb_samples, src, dst);
205  }
206 
207  s->next_pts = frame->pts + av_rescale_q(frame->nb_samples, (AVRational){1, inlink->sample_rate}, inlink->time_base);
209  return ff_filter_frame(ctx->outputs[0], out_frame);
210 }
211 
212 static int request_frame(AVFilterLink *outlink)
213 {
214  AVFilterContext *ctx = outlink->src;
215  AudioDelayContext *s = ctx->priv;
216  int ret;
217 
218  ret = ff_request_frame(ctx->inputs[0]);
219  if (ret == AVERROR_EOF && !ctx->is_disabled && s->max_delay) {
220  int nb_samples = FFMIN(s->max_delay, 2048);
221  AVFrame *frame;
222 
223  frame = ff_get_audio_buffer(outlink, nb_samples);
224  if (!frame)
225  return AVERROR(ENOMEM);
226  s->max_delay -= nb_samples;
227 
229  frame->nb_samples,
230  outlink->channels,
231  frame->format);
232 
233  frame->pts = s->next_pts;
234  if (s->next_pts != AV_NOPTS_VALUE)
235  s->next_pts += av_rescale_q(nb_samples, (AVRational){1, outlink->sample_rate}, outlink->time_base);
236 
237  ret = filter_frame(ctx->inputs[0], frame);
238  }
239 
240  return ret;
241 }
242 
243 static av_cold void uninit(AVFilterContext *ctx)
244 {
245  AudioDelayContext *s = ctx->priv;
246  int i;
247 
248  for (i = 0; i < s->nb_delays; i++)
249  av_free(s->chandelay[i].samples);
250  av_freep(&s->chandelay);
251 }
252 
253 static const AVFilterPad adelay_inputs[] = {
254  {
255  .name = "default",
256  .type = AVMEDIA_TYPE_AUDIO,
257  .config_props = config_input,
258  .filter_frame = filter_frame,
259  },
260  { NULL }
261 };
262 
263 static const AVFilterPad adelay_outputs[] = {
264  {
265  .name = "default",
266  .request_frame = request_frame,
267  .type = AVMEDIA_TYPE_AUDIO,
268  },
269  { NULL }
270 };
271 
273  .name = "adelay",
274  .description = NULL_IF_CONFIG_SMALL("Delay one or more audio channels."),
275  .query_formats = query_formats,
276  .priv_size = sizeof(AudioDelayContext),
277  .priv_class = &adelay_class,
278  .uninit = uninit,
279  .inputs = adelay_inputs,
280  .outputs = adelay_outputs,
282 };