FFmpeg
af_amerge.c
Go to the documentation of this file.
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 
62  av_freep(&s->in);
63  for (unsigned i = 0; i < ctx->nb_inputs; i++)
64  av_freep(&ctx->input_pads[i].name);
65 }
66 
68 {
69  static const enum AVSampleFormat packed_sample_fmts[] = {
76  };
77  AMergeContext *s = ctx->priv;
78  int64_t inlayout[SWR_CH_MAX], outlayout = 0;
81  int i, ret, overlap = 0, nb_ch = 0;
82 
83  for (i = 0; i < s->nb_inputs; i++) {
84  if (!ctx->inputs[i]->incfg.channel_layouts ||
87  "No channel layout for input %d\n", i + 1);
88  return AVERROR(EAGAIN);
89  }
90  inlayout[i] = ctx->inputs[i]->incfg.channel_layouts->channel_layouts[0];
91  if (ctx->inputs[i]->incfg.channel_layouts->nb_channel_layouts > 1) {
92  char buf[256];
93  av_get_channel_layout_string(buf, sizeof(buf), 0, inlayout[i]);
94  av_log(ctx, AV_LOG_INFO, "Using \"%s\" for input %d\n", buf, i + 1);
95  }
96  s->in[i].nb_ch = FF_LAYOUT2COUNT(inlayout[i]);
97  if (s->in[i].nb_ch) {
98  overlap++;
99  } else {
100  s->in[i].nb_ch = av_get_channel_layout_nb_channels(inlayout[i]);
101  if (outlayout & inlayout[i])
102  overlap++;
103  outlayout |= inlayout[i];
104  }
105  nb_ch += s->in[i].nb_ch;
106  }
107  if (nb_ch > SWR_CH_MAX) {
108  av_log(ctx, AV_LOG_ERROR, "Too many channels (max %d)\n", SWR_CH_MAX);
109  return AVERROR(EINVAL);
110  }
111  if (overlap) {
112  av_log(ctx, AV_LOG_WARNING,
113  "Input channel layouts overlap: "
114  "output layout will be determined by the number of distinct input channels\n");
115  for (i = 0; i < nb_ch; i++)
116  s->route[i] = i;
117  outlayout = av_get_default_channel_layout(nb_ch);
118  if (!outlayout && nb_ch)
119  outlayout = 0xFFFFFFFFFFFFFFFFULL >> (64 - nb_ch);
120  } else {
121  int *route[SWR_CH_MAX];
122  int c, out_ch_number = 0;
123 
124  route[0] = s->route;
125  for (i = 1; i < s->nb_inputs; i++)
126  route[i] = route[i - 1] + s->in[i - 1].nb_ch;
127  for (c = 0; c < 64; c++)
128  for (i = 0; i < s->nb_inputs; i++)
129  if ((inlayout[i] >> c) & 1)
130  *(route[i]++) = out_ch_number++;
131  }
132  formats = ff_make_format_list(packed_sample_fmts);
133  if ((ret = ff_set_common_formats(ctx, formats)) < 0)
134  return ret;
135  for (i = 0; i < s->nb_inputs; i++) {
136  layouts = NULL;
137  if ((ret = ff_add_channel_layout(&layouts, inlayout[i])) < 0)
138  return ret;
139  if ((ret = ff_channel_layouts_ref(layouts, &ctx->inputs[i]->outcfg.channel_layouts)) < 0)
140  return ret;
141  }
142  layouts = NULL;
143  if ((ret = ff_add_channel_layout(&layouts, outlayout)) < 0)
144  return ret;
145  if ((ret = ff_channel_layouts_ref(layouts, &ctx->outputs[0]->incfg.channel_layouts)) < 0)
146  return ret;
147 
149 }
150 
151 static int config_output(AVFilterLink *outlink)
152 {
153  AVFilterContext *ctx = outlink->src;
154  AMergeContext *s = ctx->priv;
155  AVBPrint bp;
156  int i;
157 
158  for (i = 1; i < s->nb_inputs; i++) {
159  if (ctx->inputs[i]->sample_rate != ctx->inputs[0]->sample_rate) {
160  av_log(ctx, AV_LOG_ERROR,
161  "Inputs must have the same sample rate "
162  "%d for in%d vs %d\n",
163  ctx->inputs[i]->sample_rate, i, ctx->inputs[0]->sample_rate);
164  return AVERROR(EINVAL);
165  }
166  }
167  s->bps = av_get_bytes_per_sample(ctx->outputs[0]->format);
168  outlink->sample_rate = ctx->inputs[0]->sample_rate;
169  outlink->time_base = ctx->inputs[0]->time_base;
170 
172  for (i = 0; i < s->nb_inputs; i++) {
173  av_bprintf(&bp, "%sin%d:", i ? " + " : "", i);
175  }
176  av_bprintf(&bp, " -> out:");
178  av_log(ctx, AV_LOG_VERBOSE, "%s\n", bp.str);
179 
180  return 0;
181 }
182 
183 /**
184  * Copy samples from several input streams to one output stream.
185  * @param nb_inputs number of inputs
186  * @param in inputs; used only for the nb_ch field;
187  * @param route routing values;
188  * input channel i goes to output channel route[i];
189  * i < in[0].nb_ch are the channels from the first output;
190  * i >= in[0].nb_ch are the channels from the second output
191  * @param ins pointer to the samples of each inputs, in packed format;
192  * will be left at the end of the copied samples
193  * @param outs pointer to the samples of the output, in packet format;
194  * must point to a buffer big enough;
195  * will be left at the end of the copied samples
196  * @param ns number of samples to copy
197  * @param bps bytes per sample
198  */
199 static inline void copy_samples(int nb_inputs, struct amerge_input in[],
200  int *route, uint8_t *ins[],
201  uint8_t **outs, int ns, int bps)
202 {
203  int *route_cur;
204  int i, c, nb_ch = 0;
205 
206  for (i = 0; i < nb_inputs; i++)
207  nb_ch += in[i].nb_ch;
208  while (ns--) {
209  route_cur = route;
210  for (i = 0; i < nb_inputs; i++) {
211  for (c = 0; c < in[i].nb_ch; c++) {
212  memcpy((*outs) + bps * *(route_cur++), ins[i], bps);
213  ins[i] += bps;
214  }
215  }
216  *outs += nb_ch * bps;
217  }
218 }
219 
220 static void free_frames(int nb_inputs, AVFrame **input_frames)
221 {
222  int i;
223  for (i = 0; i < nb_inputs; i++)
224  av_frame_free(&input_frames[i]);
225 }
226 
227 static int try_push_frame(AVFilterContext *ctx, int nb_samples)
228 {
229  AMergeContext *s = ctx->priv;
230  AVFilterLink *outlink = ctx->outputs[0];
231  int i, ret;
232  AVFrame *outbuf, *inbuf[SWR_CH_MAX] = { NULL };
233  uint8_t *outs, *ins[SWR_CH_MAX];
234 
235  for (i = 0; i < ctx->nb_inputs; i++) {
236  ret = ff_inlink_consume_samples(ctx->inputs[i], nb_samples, nb_samples, &inbuf[i]);
237  if (ret < 0) {
238  free_frames(i, inbuf);
239  return ret;
240  }
241  ins[i] = inbuf[i]->data[0];
242  }
243 
244  outbuf = ff_get_audio_buffer(ctx->outputs[0], nb_samples);
245  if (!outbuf) {
246  free_frames(s->nb_inputs, inbuf);
247  return AVERROR(ENOMEM);
248  }
249 
250  outs = outbuf->data[0];
251  outbuf->pts = inbuf[0]->pts;
252 
253  outbuf->nb_samples = nb_samples;
254  outbuf->channel_layout = outlink->channel_layout;
255  outbuf->channels = outlink->channels;
256 
257  while (nb_samples) {
258  /* Unroll the most common sample formats: speed +~350% for the loop,
259  +~13% overall (including two common decoders) */
260  switch (s->bps) {
261  case 1:
262  copy_samples(s->nb_inputs, s->in, s->route, ins, &outs, nb_samples, 1);
263  break;
264  case 2:
265  copy_samples(s->nb_inputs, s->in, s->route, ins, &outs, nb_samples, 2);
266  break;
267  case 4:
268  copy_samples(s->nb_inputs, s->in, s->route, ins, &outs, nb_samples, 4);
269  break;
270  default:
271  copy_samples(s->nb_inputs, s->in, s->route, ins, &outs, nb_samples, s->bps);
272  break;
273  }
274 
275  nb_samples = 0;
276  }
277 
278  free_frames(s->nb_inputs, inbuf);
279  return ff_filter_frame(ctx->outputs[0], outbuf);
280 }
281 
283 {
284  int i, status;
285  int ret, nb_samples;
286  int64_t pts;
287 
289 
290  nb_samples = ff_inlink_queued_samples(ctx->inputs[0]);
291  for (i = 1; i < ctx->nb_inputs && nb_samples > 0; i++) {
292  nb_samples = FFMIN(ff_inlink_queued_samples(ctx->inputs[i]), nb_samples);
293  }
294 
295  if (nb_samples) {
296  ret = try_push_frame(ctx, nb_samples);
297  if (ret < 0)
298  return ret;
299  }
300 
301  for (i = 0; i < ctx->nb_inputs; i++) {
302  if (ff_inlink_queued_samples(ctx->inputs[i]))
303  continue;
304 
305  if (ff_inlink_acknowledge_status(ctx->inputs[i], &status, &pts)) {
306  ff_outlink_set_status(ctx->outputs[0], status, pts);
307  return 0;
308  } else if (ff_outlink_frame_wanted(ctx->outputs[0])) {
310  return 0;
311  }
312  }
313 
314  return 0;
315 }
316 
318 {
319  AMergeContext *s = ctx->priv;
320  int i, ret;
321 
322  s->in = av_calloc(s->nb_inputs, sizeof(*s->in));
323  if (!s->in)
324  return AVERROR(ENOMEM);
325  for (i = 0; i < s->nb_inputs; i++) {
326  char *name = av_asprintf("in%d", i);
327  AVFilterPad pad = {
328  .name = name,
329  .type = AVMEDIA_TYPE_AUDIO,
330  };
331  if (!name)
332  return AVERROR(ENOMEM);
333  if ((ret = ff_insert_inpad(ctx, i, &pad)) < 0) {
334  av_freep(&pad.name);
335  return ret;
336  }
337  }
338  return 0;
339 }
340 
341 static const AVFilterPad amerge_outputs[] = {
342  {
343  .name = "default",
344  .type = AVMEDIA_TYPE_AUDIO,
345  .config_props = config_output,
346  },
347  { NULL }
348 };
349 
351  .name = "amerge",
352  .description = NULL_IF_CONFIG_SMALL("Merge two or more audio streams into "
353  "a single multi-channel stream."),
354  .priv_size = sizeof(AMergeContext),
355  .init = init,
356  .uninit = uninit,
358  .activate = activate,
359  .inputs = NULL,
360  .outputs = amerge_outputs,
361  .priv_class = &amerge_class,
363 };
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:308
AVOption.
Definition: opt.h:248
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#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:106
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:1615
void * av_calloc(size_t nmemb, size_t size)
Non-inlined equivalent of av_mallocz_array().
Definition: mem.c:245
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:287
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:349
static int activate(AVFilterContext *ctx)
Definition: af_amerge.c:282
int ff_channel_layouts_ref(AVFilterChannelLayouts *f, AVFilterChannelLayouts **ref)
Add *ref as a new reference to f.
Definition: formats.c:462
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1091
uint8_t
#define av_cold
Definition: attributes.h:88
AV_SAMPLE_FMT_U8
AVOptions.
#define FF_LAYOUT2COUNT(l)
Decode a channel count encoded as a channel layout.
Definition: formats.h:109
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:401
static av_cold int init(AVFilterContext *ctx)
Definition: af_amerge.c:317
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:210
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
signed 32 bits
Definition: samplefmt.h:62
#define av_log(a,...)
static void free_frames(int nb_inputs, AVFrame **input_frames)
Definition: af_amerge.c:220
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:1444
static const AVFilterPad amerge_outputs[]
Definition: af_amerge.c:341
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:348
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
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:588
static const AVOption amerge_options[]
Definition: af_amerge.c:50
int ff_add_channel_layout(AVFilterChannelLayouts **l, uint64_t channel_layout)
Definition: formats.c:339
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:203
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:153
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:356
uint64_t * channel_layouts
list of channel layouts
Definition: formats.h:87
uint64_t channel_layout
Channel layout of the audio data.
Definition: frame.h:485
char * av_asprintf(const char *fmt,...)
Definition: avstring.c:113
static int config_output(AVFilterLink *outlink)
Definition: af_amerge.c:151
int channels
number of audio channels, only used for audio.
Definition: frame.h:614
audio channel layout utility functions
unsigned nb_inputs
number of input pads
Definition: avfilter.h:350
#define FFMIN(a, b)
Definition: common.h:96
AVFilterChannelLayouts * channel_layouts
Lists of supported channel layouts, only for audio.
Definition: avfilter.h:455
int ff_inlink_queued_samples(AVFilterLink *link)
Definition: avfilter.c:1469
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:227
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
A list of supported channel layouts.
Definition: formats.h:86
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:67
#define AV_LOG_INFO
Standard information.
Definition: log.h:205
#define AV_BPRINT_SIZE_AUTOMATIC
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
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:1508
AVFilter ff_af_amerge
Definition: af_amerge.c:350
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:145
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:149
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:353
enum MovChannelLayoutTag * layouts
Definition: mov_chan.c:434
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:422
static int64_t pts
#define flags(name, subs,...)
Definition: cbs_av1.c:560
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:322
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:681
int nb_channel_layouts
number of channel layouts
Definition: formats.h:88
#define OFFSET(x)
Definition: af_amerge.c:47
signed 16 bits
Definition: samplefmt.h:61
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:65
An instance of a filter.
Definition: avfilter.h:341
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:199
#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:374
for(j=16;j >0;--j)
int ff_set_common_samplerates(AVFilterContext *ctx, AVFilterFormats *samplerates)
Definition: formats.c:576
int i
Definition: input.c:407
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:240