Imported Debian version 2.4.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavfilter / af_asyncts.c
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2ba45a60
DM
1/*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19#include <stdint.h>
20
21#include "libavresample/avresample.h"
22#include "libavutil/attributes.h"
23#include "libavutil/audio_fifo.h"
24#include "libavutil/common.h"
25#include "libavutil/mathematics.h"
26#include "libavutil/opt.h"
27#include "libavutil/samplefmt.h"
28
29#include "audio.h"
30#include "avfilter.h"
31#include "internal.h"
32
33typedef struct ASyncContext {
34 const AVClass *class;
35
36 AVAudioResampleContext *avr;
37 int64_t pts; ///< timestamp in samples of the first sample in fifo
38 int min_delta; ///< pad/trim min threshold in samples
39 int first_frame; ///< 1 until filter_frame() has processed at least 1 frame with a pts != AV_NOPTS_VALUE
40 int64_t first_pts; ///< user-specified first expected pts, in samples
41 int comp; ///< current resample compensation
42
43 /* options */
44 int resample;
45 float min_delta_sec;
46 int max_comp;
47
48 /* set by filter_frame() to signal an output frame to request_frame() */
49 int got_output;
50} ASyncContext;
51
52#define OFFSET(x) offsetof(ASyncContext, x)
53#define A AV_OPT_FLAG_AUDIO_PARAM
54#define F AV_OPT_FLAG_FILTERING_PARAM
55static const AVOption asyncts_options[] = {
56 { "compensate", "Stretch/squeeze the data to make it match the timestamps", OFFSET(resample), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, A|F },
57 { "min_delta", "Minimum difference between timestamps and audio data "
58 "(in seconds) to trigger padding/trimmin the data.", OFFSET(min_delta_sec), AV_OPT_TYPE_FLOAT, { .dbl = 0.1 }, 0, INT_MAX, A|F },
59 { "max_comp", "Maximum compensation in samples per second.", OFFSET(max_comp), AV_OPT_TYPE_INT, { .i64 = 500 }, 0, INT_MAX, A|F },
60 { "first_pts", "Assume the first pts should be this value.", OFFSET(first_pts), AV_OPT_TYPE_INT64, { .i64 = AV_NOPTS_VALUE }, INT64_MIN, INT64_MAX, A|F },
61 { NULL }
62};
63
64AVFILTER_DEFINE_CLASS(asyncts);
65
66static av_cold int init(AVFilterContext *ctx)
67{
68 ASyncContext *s = ctx->priv;
69
70 s->pts = AV_NOPTS_VALUE;
71 s->first_frame = 1;
72
73 return 0;
74}
75
76static av_cold void uninit(AVFilterContext *ctx)
77{
78 ASyncContext *s = ctx->priv;
79
80 if (s->avr) {
81 avresample_close(s->avr);
82 avresample_free(&s->avr);
83 }
84}
85
86static int config_props(AVFilterLink *link)
87{
88 ASyncContext *s = link->src->priv;
89 int ret;
90
91 s->min_delta = s->min_delta_sec * link->sample_rate;
92 link->time_base = (AVRational){1, link->sample_rate};
93
94 s->avr = avresample_alloc_context();
95 if (!s->avr)
96 return AVERROR(ENOMEM);
97
98 av_opt_set_int(s->avr, "in_channel_layout", link->channel_layout, 0);
99 av_opt_set_int(s->avr, "out_channel_layout", link->channel_layout, 0);
100 av_opt_set_int(s->avr, "in_sample_fmt", link->format, 0);
101 av_opt_set_int(s->avr, "out_sample_fmt", link->format, 0);
102 av_opt_set_int(s->avr, "in_sample_rate", link->sample_rate, 0);
103 av_opt_set_int(s->avr, "out_sample_rate", link->sample_rate, 0);
104
105 if (s->resample)
106 av_opt_set_int(s->avr, "force_resampling", 1, 0);
107
108 if ((ret = avresample_open(s->avr)) < 0)
109 return ret;
110
111 return 0;
112}
113
114/* get amount of data currently buffered, in samples */
115static int64_t get_delay(ASyncContext *s)
116{
117 return avresample_available(s->avr) + avresample_get_delay(s->avr);
118}
119
120static void handle_trimming(AVFilterContext *ctx)
121{
122 ASyncContext *s = ctx->priv;
123
124 if (s->pts < s->first_pts) {
125 int delta = FFMIN(s->first_pts - s->pts, avresample_available(s->avr));
126 av_log(ctx, AV_LOG_VERBOSE, "Trimming %d samples from start\n",
127 delta);
128 avresample_read(s->avr, NULL, delta);
129 s->pts += delta;
130 } else if (s->first_frame)
131 s->pts = s->first_pts;
132}
133
134static int request_frame(AVFilterLink *link)
135{
136 AVFilterContext *ctx = link->src;
137 ASyncContext *s = ctx->priv;
138 int ret = 0;
139 int nb_samples;
140
141 s->got_output = 0;
142 while (ret >= 0 && !s->got_output)
143 ret = ff_request_frame(ctx->inputs[0]);
144
145 /* flush the fifo */
146 if (ret == AVERROR_EOF) {
147 if (s->first_pts != AV_NOPTS_VALUE)
148 handle_trimming(ctx);
149
150 if (nb_samples = get_delay(s)) {
151 AVFrame *buf = ff_get_audio_buffer(link, nb_samples);
152 if (!buf)
153 return AVERROR(ENOMEM);
154 ret = avresample_convert(s->avr, buf->extended_data,
155 buf->linesize[0], nb_samples, NULL, 0, 0);
156 if (ret <= 0) {
157 av_frame_free(&buf);
158 return (ret < 0) ? ret : AVERROR_EOF;
159 }
160
161 buf->pts = s->pts;
162 return ff_filter_frame(link, buf);
163 }
164 }
165
166 return ret;
167}
168
169static int write_to_fifo(ASyncContext *s, AVFrame *buf)
170{
171 int ret = avresample_convert(s->avr, NULL, 0, 0, buf->extended_data,
172 buf->linesize[0], buf->nb_samples);
173 av_frame_free(&buf);
174 return ret;
175}
176
177static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
178{
179 AVFilterContext *ctx = inlink->dst;
180 ASyncContext *s = ctx->priv;
181 AVFilterLink *outlink = ctx->outputs[0];
182 int nb_channels = av_get_channel_layout_nb_channels(buf->channel_layout);
183 int64_t pts = (buf->pts == AV_NOPTS_VALUE) ? buf->pts :
184 av_rescale_q(buf->pts, inlink->time_base, outlink->time_base);
185 int out_size, ret;
186 int64_t delta;
187 int64_t new_pts;
188
189 /* buffer data until we get the next timestamp */
190 if (s->pts == AV_NOPTS_VALUE || pts == AV_NOPTS_VALUE) {
191 if (pts != AV_NOPTS_VALUE) {
192 s->pts = pts - get_delay(s);
193 }
194 return write_to_fifo(s, buf);
195 }
196
197 if (s->first_pts != AV_NOPTS_VALUE) {
198 handle_trimming(ctx);
199 if (!avresample_available(s->avr))
200 return write_to_fifo(s, buf);
201 }
202
203 /* when we have two timestamps, compute how many samples would we have
204 * to add/remove to get proper sync between data and timestamps */
205 delta = pts - s->pts - get_delay(s);
206 out_size = avresample_available(s->avr);
207
208 if (labs(delta) > s->min_delta ||
209 (s->first_frame && delta && s->first_pts != AV_NOPTS_VALUE)) {
210 av_log(ctx, AV_LOG_VERBOSE, "Discontinuity - %"PRId64" samples.\n", delta);
211 out_size = av_clipl_int32((int64_t)out_size + delta);
212 } else {
213 if (s->resample) {
214 // adjust the compensation if delta is non-zero
215 int delay = get_delay(s);
216 int comp = s->comp + av_clip(delta * inlink->sample_rate / delay,
217 -s->max_comp, s->max_comp);
218 if (comp != s->comp) {
219 av_log(ctx, AV_LOG_VERBOSE, "Compensating %d samples per second.\n", comp);
220 if (avresample_set_compensation(s->avr, comp, inlink->sample_rate) == 0) {
221 s->comp = comp;
222 }
223 }
224 }
225 // adjust PTS to avoid monotonicity errors with input PTS jitter
226 pts -= delta;
227 delta = 0;
228 }
229
230 if (out_size > 0) {
231 AVFrame *buf_out = ff_get_audio_buffer(outlink, out_size);
232 if (!buf_out) {
233 ret = AVERROR(ENOMEM);
234 goto fail;
235 }
236
237 if (s->first_frame && delta > 0) {
238 int planar = av_sample_fmt_is_planar(buf_out->format);
239 int planes = planar ? nb_channels : 1;
240 int block_size = av_get_bytes_per_sample(buf_out->format) *
241 (planar ? 1 : nb_channels);
242
243 int ch;
244
245 av_samples_set_silence(buf_out->extended_data, 0, delta,
246 nb_channels, buf->format);
247
248 for (ch = 0; ch < planes; ch++)
249 buf_out->extended_data[ch] += delta * block_size;
250
251 avresample_read(s->avr, buf_out->extended_data, out_size);
252
253 for (ch = 0; ch < planes; ch++)
254 buf_out->extended_data[ch] -= delta * block_size;
255 } else {
256 avresample_read(s->avr, buf_out->extended_data, out_size);
257
258 if (delta > 0) {
259 av_samples_set_silence(buf_out->extended_data, out_size - delta,
260 delta, nb_channels, buf->format);
261 }
262 }
263 buf_out->pts = s->pts;
264 ret = ff_filter_frame(outlink, buf_out);
265 if (ret < 0)
266 goto fail;
267 s->got_output = 1;
268 } else if (avresample_available(s->avr)) {
269 av_log(ctx, AV_LOG_WARNING, "Non-monotonous timestamps, dropping "
270 "whole buffer.\n");
271 }
272
273 /* drain any remaining buffered data */
274 avresample_read(s->avr, NULL, avresample_available(s->avr));
275
276 new_pts = pts - avresample_get_delay(s->avr);
277 /* check for s->pts monotonicity */
278 if (new_pts > s->pts) {
279 s->pts = new_pts;
280 ret = avresample_convert(s->avr, NULL, 0, 0, buf->extended_data,
281 buf->linesize[0], buf->nb_samples);
282 } else {
283 av_log(ctx, AV_LOG_WARNING, "Non-monotonous timestamps, dropping "
284 "whole buffer.\n");
285 ret = 0;
286 }
287
288 s->first_frame = 0;
289fail:
290 av_frame_free(&buf);
291
292 return ret;
293}
294
295static const AVFilterPad avfilter_af_asyncts_inputs[] = {
296 {
297 .name = "default",
298 .type = AVMEDIA_TYPE_AUDIO,
299 .filter_frame = filter_frame
300 },
301 { NULL }
302};
303
304static const AVFilterPad avfilter_af_asyncts_outputs[] = {
305 {
306 .name = "default",
307 .type = AVMEDIA_TYPE_AUDIO,
308 .config_props = config_props,
309 .request_frame = request_frame
310 },
311 { NULL }
312};
313
314AVFilter ff_af_asyncts = {
315 .name = "asyncts",
316 .description = NULL_IF_CONFIG_SMALL("Sync audio data to timestamps"),
317 .init = init,
318 .uninit = uninit,
319 .priv_size = sizeof(ASyncContext),
320 .priv_class = &asyncts_class,
321 .inputs = avfilter_af_asyncts_inputs,
322 .outputs = avfilter_af_asyncts_outputs,
323};