FFmpeg
af_amerge.c
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1 /*
2  * Copyright (c) 2011 Nicolas George <nicolas.george@normalesup.org>
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
14  * GNU 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 /**
22  * @file
23  * Audio merging filter
24  */
25 
26 #include "libavutil/avstring.h"
27 #include "libavutil/bprint.h"
29 #include "libavutil/opt.h"
30 #include "avfilter.h"
31 #include "filters.h"
32 #include "audio.h"
33 #include "internal.h"
34 
35 #define SWR_CH_MAX 64
36 
37 typedef struct AMergeContext {
38  const AVClass *class;
39  int nb_inputs;
40  int route[SWR_CH_MAX]; /**< channels routing, see copy_samples */
41  int bps;
42  struct amerge_input {
43  int nb_ch; /**< number of channels for the input */
44  } *in;
46 
47 #define OFFSET(x) offsetof(AMergeContext, x)
48 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
49 
50 static const AVOption amerge_options[] = {
51  { "inputs", "specify the number of inputs", OFFSET(nb_inputs),
52  AV_OPT_TYPE_INT, { .i64 = 2 }, 1, SWR_CH_MAX, FLAGS },
53  { NULL }
54 };
55 
56 AVFILTER_DEFINE_CLASS(amerge);
57 
59 {
60  AMergeContext *s = ctx->priv;
61  int i;
62 
63  for (i = 0; i < s->nb_inputs; i++) {
64  if (ctx->input_pads)
65  av_freep(&ctx->input_pads[i].name);
66  }
67  av_freep(&s->in);
68 }
69 
71 {
72  AMergeContext *s = ctx->priv;
73  int64_t inlayout[SWR_CH_MAX], outlayout = 0;
76  int i, ret, overlap = 0, nb_ch = 0;
77 
78  for (i = 0; i < s->nb_inputs; i++) {
79  if (!ctx->inputs[i]->in_channel_layouts ||
82  "No channel layout for input %d\n", i + 1);
83  return AVERROR(EAGAIN);
84  }
85  inlayout[i] = ctx->inputs[i]->in_channel_layouts->channel_layouts[0];
86  if (ctx->inputs[i]->in_channel_layouts->nb_channel_layouts > 1) {
87  char buf[256];
88  av_get_channel_layout_string(buf, sizeof(buf), 0, inlayout[i]);
89  av_log(ctx, AV_LOG_INFO, "Using \"%s\" for input %d\n", buf, i + 1);
90  }
91  s->in[i].nb_ch = FF_LAYOUT2COUNT(inlayout[i]);
92  if (s->in[i].nb_ch) {
93  overlap++;
94  } else {
95  s->in[i].nb_ch = av_get_channel_layout_nb_channels(inlayout[i]);
96  if (outlayout & inlayout[i])
97  overlap++;
98  outlayout |= inlayout[i];
99  }
100  nb_ch += s->in[i].nb_ch;
101  }
102  if (nb_ch > SWR_CH_MAX) {
103  av_log(ctx, AV_LOG_ERROR, "Too many channels (max %d)\n", SWR_CH_MAX);
104  return AVERROR(EINVAL);
105  }
106  if (overlap) {
107  av_log(ctx, AV_LOG_WARNING,
108  "Input channel layouts overlap: "
109  "output layout will be determined by the number of distinct input channels\n");
110  for (i = 0; i < nb_ch; i++)
111  s->route[i] = i;
112  outlayout = av_get_default_channel_layout(nb_ch);
113  if (!outlayout && nb_ch)
114  outlayout = 0xFFFFFFFFFFFFFFFFULL >> (64 - nb_ch);
115  } else {
116  int *route[SWR_CH_MAX];
117  int c, out_ch_number = 0;
118 
119  route[0] = s->route;
120  for (i = 1; i < s->nb_inputs; i++)
121  route[i] = route[i - 1] + s->in[i - 1].nb_ch;
122  for (c = 0; c < 64; c++)
123  for (i = 0; i < s->nb_inputs; i++)
124  if ((inlayout[i] >> c) & 1)
125  *(route[i]++) = out_ch_number++;
126  }
128  if ((ret = ff_set_common_formats(ctx, formats)) < 0)
129  return ret;
130  for (i = 0; i < s->nb_inputs; i++) {
131  layouts = NULL;
132  if ((ret = ff_add_channel_layout(&layouts, inlayout[i])) < 0)
133  return ret;
134  if ((ret = ff_channel_layouts_ref(layouts, &ctx->inputs[i]->out_channel_layouts)) < 0)
135  return ret;
136  }
137  layouts = NULL;
138  if ((ret = ff_add_channel_layout(&layouts, outlayout)) < 0)
139  return ret;
140  if ((ret = ff_channel_layouts_ref(layouts, &ctx->outputs[0]->in_channel_layouts)) < 0)
141  return ret;
142 
144 }
145 
146 static int config_output(AVFilterLink *outlink)
147 {
148  AVFilterContext *ctx = outlink->src;
149  AMergeContext *s = ctx->priv;
150  AVBPrint bp;
151  int i;
152 
153  for (i = 1; i < s->nb_inputs; i++) {
154  if (ctx->inputs[i]->sample_rate != ctx->inputs[0]->sample_rate) {
155  av_log(ctx, AV_LOG_ERROR,
156  "Inputs must have the same sample rate "
157  "%d for in%d vs %d\n",
158  ctx->inputs[i]->sample_rate, i, ctx->inputs[0]->sample_rate);
159  return AVERROR(EINVAL);
160  }
161  }
162  s->bps = av_get_bytes_per_sample(ctx->outputs[0]->format);
163  outlink->sample_rate = ctx->inputs[0]->sample_rate;
164  outlink->time_base = ctx->inputs[0]->time_base;
165 
167  for (i = 0; i < s->nb_inputs; i++) {
168  av_bprintf(&bp, "%sin%d:", i ? " + " : "", i);
170  }
171  av_bprintf(&bp, " -> out:");
173  av_log(ctx, AV_LOG_VERBOSE, "%s\n", bp.str);
174 
175  return 0;
176 }
177 
178 /**
179  * Copy samples from several input streams to one output stream.
180  * @param nb_inputs number of inputs
181  * @param in inputs; used only for the nb_ch field;
182  * @param route routing values;
183  * input channel i goes to output channel route[i];
184  * i < in[0].nb_ch are the channels from the first output;
185  * i >= in[0].nb_ch are the channels from the second output
186  * @param ins pointer to the samples of each inputs, in packed format;
187  * will be left at the end of the copied samples
188  * @param outs pointer to the samples of the output, in packet format;
189  * must point to a buffer big enough;
190  * will be left at the end of the copied samples
191  * @param ns number of samples to copy
192  * @param bps bytes per sample
193  */
194 static inline void copy_samples(int nb_inputs, struct amerge_input in[],
195  int *route, uint8_t *ins[],
196  uint8_t **outs, int ns, int bps)
197 {
198  int *route_cur;
199  int i, c, nb_ch = 0;
200 
201  for (i = 0; i < nb_inputs; i++)
202  nb_ch += in[i].nb_ch;
203  while (ns--) {
204  route_cur = route;
205  for (i = 0; i < nb_inputs; i++) {
206  for (c = 0; c < in[i].nb_ch; c++) {
207  memcpy((*outs) + bps * *(route_cur++), ins[i], bps);
208  ins[i] += bps;
209  }
210  }
211  *outs += nb_ch * bps;
212  }
213 }
214 
215 static void free_frames(int nb_inputs, AVFrame **input_frames)
216 {
217  int i;
218  for (i = 0; i < nb_inputs; i++)
219  av_frame_free(&input_frames[i]);
220 }
221 
222 static int try_push_frame(AVFilterContext *ctx, int nb_samples)
223 {
224  AMergeContext *s = ctx->priv;
225  AVFilterLink *outlink = ctx->outputs[0];
226  int i, ret;
227  AVFrame *outbuf, *inbuf[SWR_CH_MAX] = { NULL };
228  uint8_t *outs, *ins[SWR_CH_MAX];
229 
230  for (i = 0; i < ctx->nb_inputs; i++) {
231  ret = ff_inlink_consume_samples(ctx->inputs[i], nb_samples, nb_samples, &inbuf[i]);
232  if (ret < 0) {
233  free_frames(i, inbuf);
234  return ret;
235  }
236  ins[i] = inbuf[i]->data[0];
237  }
238 
239  outbuf = ff_get_audio_buffer(ctx->outputs[0], nb_samples);
240  if (!outbuf) {
241  free_frames(s->nb_inputs, inbuf);
242  return AVERROR(ENOMEM);
243  }
244 
245  outs = outbuf->data[0];
246  outbuf->pts = inbuf[0]->pts;
247 
248  outbuf->nb_samples = nb_samples;
249  outbuf->channel_layout = outlink->channel_layout;
250  outbuf->channels = outlink->channels;
251 
252  while (nb_samples) {
253  /* Unroll the most common sample formats: speed +~350% for the loop,
254  +~13% overall (including two common decoders) */
255  switch (s->bps) {
256  case 1:
257  copy_samples(s->nb_inputs, s->in, s->route, ins, &outs, nb_samples, 1);
258  break;
259  case 2:
260  copy_samples(s->nb_inputs, s->in, s->route, ins, &outs, nb_samples, 2);
261  break;
262  case 4:
263  copy_samples(s->nb_inputs, s->in, s->route, ins, &outs, nb_samples, 4);
264  break;
265  default:
266  copy_samples(s->nb_inputs, s->in, s->route, ins, &outs, nb_samples, s->bps);
267  break;
268  }
269 
270  nb_samples = 0;
271  }
272 
273  free_frames(s->nb_inputs, inbuf);
274  return ff_filter_frame(ctx->outputs[0], outbuf);
275 }
276 
278 {
279  int i, status;
280  int ret, nb_samples;
281  int64_t pts;
282 
284 
285  nb_samples = ff_inlink_queued_samples(ctx->inputs[0]);
286  for (i = 1; i < ctx->nb_inputs && nb_samples > 0; i++) {
287  nb_samples = FFMIN(ff_inlink_queued_samples(ctx->inputs[i]), nb_samples);
288  }
289 
290  if (nb_samples) {
291  ret = try_push_frame(ctx, nb_samples);
292  if (ret < 0)
293  return ret;
294  }
295 
296  for (i = 0; i < ctx->nb_inputs; i++) {
297  if (ff_inlink_queued_samples(ctx->inputs[i]))
298  continue;
299 
300  if (ff_inlink_acknowledge_status(ctx->inputs[i], &status, &pts)) {
301  ff_outlink_set_status(ctx->outputs[0], status, pts);
302  return 0;
303  } else if (ff_outlink_frame_wanted(ctx->outputs[0])) {
305  return 0;
306  }
307  }
308 
309  return 0;
310 }
311 
313 {
314  AMergeContext *s = ctx->priv;
315  int i, ret;
316 
317  s->in = av_calloc(s->nb_inputs, sizeof(*s->in));
318  if (!s->in)
319  return AVERROR(ENOMEM);
320  for (i = 0; i < s->nb_inputs; i++) {
321  char *name = av_asprintf("in%d", i);
322  AVFilterPad pad = {
323  .name = name,
324  .type = AVMEDIA_TYPE_AUDIO,
325  };
326  if (!name)
327  return AVERROR(ENOMEM);
328  if ((ret = ff_insert_inpad(ctx, i, &pad)) < 0) {
329  av_freep(&pad.name);
330  return ret;
331  }
332  }
333  return 0;
334 }
335 
336 static const AVFilterPad amerge_outputs[] = {
337  {
338  .name = "default",
339  .type = AVMEDIA_TYPE_AUDIO,
340  .config_props = config_output,
341  },
342  { NULL }
343 };
344 
346  .name = "amerge",
347  .description = NULL_IF_CONFIG_SMALL("Merge two or more audio streams into "
348  "a single multi-channel stream."),
349  .priv_size = sizeof(AMergeContext),
350  .init = init,
351  .uninit = uninit,
353  .activate = activate,
354  .inputs = NULL,
355  .outputs = amerge_outputs,
356  .priv_class = &amerge_class,
358 };
struct AMergeContext::amerge_input * in
#define NULL
Definition: coverity.c:32
void av_bprintf(AVBPrint *buf, const char *fmt,...)
Definition: bprint.c:94
int nb_ch
number of channels for the input
Definition: af_amerge.c:43
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, filter)
Forward the status on an output link to all input links.
Definition: filters.h:212
Main libavfilter public API header.
#define SWR_CH_MAX
Definition: af_amerge.c:35
#define AVFILTER_FLAG_DYNAMIC_INPUTS
The number of the filter inputs is not determined just by AVFilter.inputs.
Definition: avfilter.h:105
AVFILTER_DEFINE_CLASS(amerge)
static void ff_outlink_set_status(AVFilterLink *link, int status, int64_t pts)
Set the status field of a link from the source filter.
Definition: filters.h:189
void ff_inlink_request_frame(AVFilterLink *link)
Mark that a frame is wanted on the link.
Definition: avfilter.c:1620
void * av_calloc(size_t nmemb, size_t size)
Non-inlined equivalent of av_mallocz_array().
Definition: mem.c:244
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
int av_get_channel_layout_nb_channels(uint64_t channel_layout)
Return the number of channels in the channel layout.
const char * name
Pad name.
Definition: internal.h:60
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:346
static int activate(AVFilterContext *ctx)
Definition: af_amerge.c:277
int ff_channel_layouts_ref(AVFilterChannelLayouts *f, AVFilterChannelLayouts **ref)
Add *ref as a new reference to f.
Definition: formats.c:434
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1093
uint8_t
#define av_cold
Definition: attributes.h:82
AVOptions.
#define FF_LAYOUT2COUNT(l)
Decode a channel count encoded as a channel layout.
Definition: formats.h:108
static enum AVSampleFormat ff_packed_sample_fmts_array[]
Definition: audio.h:28
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:388
static av_cold int init(AVFilterContext *ctx)
Definition: af_amerge.c:312
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
the definition of that something depends on the semantic of the filter The callback must examine the status of the filter s links and proceed accordingly The status of output links is stored in the status_in and status_out fields and tested by the ff_outlink_frame_wanted() function.If this function returns true
#define av_log(a,...)
static void free_frames(int nb_inputs, AVFrame **input_frames)
Definition: af_amerge.c:215
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_amerge.c:58
A filter pad used for either input or output.
Definition: internal.h:54
int ff_inlink_acknowledge_status(AVFilterLink *link, int *rstatus, int64_t *rpts)
Test and acknowledge the change of status on the link.
Definition: avfilter.c:1449
static const AVFilterPad amerge_outputs[]
Definition: af_amerge.c:336
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:345
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
A helper for query_formats() which sets all links to the same list of formats.
Definition: formats.c:569
static const AVOption amerge_options[]
Definition: af_amerge.c:50
int ff_add_channel_layout(AVFilterChannelLayouts **l, uint64_t channel_layout)
Definition: formats.c:342
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
Definition: audio.c:86
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
void * priv
private data for use by the filter
Definition: avfilter.h:353
uint64_t * channel_layouts
list of channel layouts
Definition: formats.h:86
uint64_t channel_layout
Channel layout of the audio data.
Definition: frame.h:472
char * av_asprintf(const char *fmt,...)
Definition: avstring.c:113
static int config_output(AVFilterLink *outlink)
Definition: af_amerge.c:146
int channels
number of audio channels, only used for audio.
Definition: frame.h:601
audio channel layout utility functions
unsigned nb_inputs
number of input pads
Definition: avfilter.h:347
#define FFMIN(a, b)
Definition: common.h:96
int ff_inlink_queued_samples(AVFilterLink *link)
Definition: avfilter.c:1474
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
static int try_push_frame(AVFilterContext *ctx, int nb_samples)
Definition: af_amerge.c:222
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
A list of supported channel layouts.
Definition: formats.h:85
void av_bprint_channel_layout(struct AVBPrint *bp, int nb_channels, uint64_t channel_layout)
Append a description of a channel layout to a bprint buffer.
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.
#define FLAGS
Definition: af_amerge.c:48
static int query_formats(AVFilterContext *ctx)
Definition: af_amerge.c:70
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
#define AV_BPRINT_SIZE_AUTOMATIC
int ff_inlink_consume_samples(AVFilterLink *link, unsigned min, unsigned max, AVFrame **rframe)
Take samples from the link&#39;s FIFO and update the link&#39;s stats.
Definition: avfilter.c:1513
AVFilter ff_af_amerge
Definition: af_amerge.c:345
void * buf
Definition: avisynth_c.h:766
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
they must not be accessed directly The fifo field contains the frames that are queued in the input for processing by the filter The status_in and status_out fields contains the queued status(EOF or error) of the link
const char * name
Filter name.
Definition: avfilter.h:148
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
enum MovChannelLayoutTag * layouts
Definition: mov_chan.c:434
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:394
static int64_t pts
#define flags(name, subs,...)
Definition: cbs_av1.c:561
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt)
Return number of bytes per sample.
Definition: samplefmt.c:106
#define ns(max_value, name, subs,...)
Definition: cbs_av1.c:682
int nb_channel_layouts
number of channel layouts
Definition: formats.h:87
#define OFFSET(x)
Definition: af_amerge.c:47
int route[SWR_CH_MAX]
channels routing, see copy_samples
Definition: af_amerge.c:40
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:338
int64_t av_get_default_channel_layout(int nb_channels)
Return default channel layout for a given number of channels.
static void copy_samples(int nb_inputs, struct amerge_input in[], int *route, uint8_t *ins[], uint8_t **outs, int ns, int bps)
Copy samples from several input streams to one output stream.
Definition: af_amerge.c:194
#define av_freep(p)
formats
Definition: signature.h:48
internal API functions
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:361
for(j=16;j >0;--j)
int ff_set_common_samplerates(AVFilterContext *ctx, AVFilterFormats *samplerates)
Definition: formats.c:557
const char * name
Definition: opengl_enc.c:102
static int ff_insert_inpad(AVFilterContext *f, unsigned index, AVFilterPad *p)
Insert a new input pad for the filter.
Definition: internal.h:277