FFmpeg
af_asetnsamples.c
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1 /*
2  * Copyright (c) 2012 Andrey Utkin
3  * Copyright (c) 2012 Stefano Sabatini
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  * Filter that changes number of samples on single output operation
25  */
26 
28 #include "libavutil/opt.h"
29 #include "avfilter.h"
30 #include "audio.h"
31 #include "filters.h"
32 #include "internal.h"
33 
34 typedef struct ASNSContext {
35  const AVClass *class;
36  int nb_out_samples; ///< how many samples to output
37  int pad;
38 } ASNSContext;
39 
40 #define OFFSET(x) offsetof(ASNSContext, x)
41 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
42 
43 static const AVOption asetnsamples_options[] = {
44  { "nb_out_samples", "set the number of per-frame output samples", OFFSET(nb_out_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, FLAGS },
45  { "n", "set the number of per-frame output samples", OFFSET(nb_out_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, FLAGS },
46  { "pad", "pad last frame with zeros", OFFSET(pad), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS },
47  { "p", "pad last frame with zeros", OFFSET(pad), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS },
48  { NULL }
49 };
50 
51 AVFILTER_DEFINE_CLASS(asetnsamples);
52 
54 {
55  AVFilterLink *inlink = ctx->inputs[0];
56  AVFilterLink *outlink = ctx->outputs[0];
57  ASNSContext *s = ctx->priv;
58  AVFrame *frame = NULL, *pad_frame;
59  int ret;
60 
62 
63  if (ctx->is_disabled)
65  else
66  ret = ff_inlink_consume_samples(inlink, s->nb_out_samples, s->nb_out_samples, &frame);
67  if (ret < 0)
68  return ret;
69 
70  if (ret > 0) {
71  if (!s->pad || ctx->is_disabled || frame->nb_samples == s->nb_out_samples)
72  return ff_filter_frame(outlink, frame);
73 
74  pad_frame = ff_get_audio_buffer(outlink, s->nb_out_samples);
75  if (!pad_frame) {
77  return AVERROR(ENOMEM);
78  }
79 
80  ret = av_frame_copy_props(pad_frame, frame);
81  if (ret < 0) {
82  av_frame_free(&pad_frame);
84  return ret;
85  }
86 
87  av_samples_copy(pad_frame->extended_data, frame->extended_data,
89  av_samples_set_silence(pad_frame->extended_data, frame->nb_samples,
90  s->nb_out_samples - frame->nb_samples, frame->ch_layout.nb_channels,
91  frame->format);
93  return ff_filter_frame(outlink, pad_frame);
94  }
95 
97  if (ff_inlink_queued_samples(inlink) >= s->nb_out_samples) {
99  return 0;
100  }
102 
103  return FFERROR_NOT_READY;
104 }
105 
107  .name = "asetnsamples",
108  .description = NULL_IF_CONFIG_SMALL("Set the number of samples for each output audio frames."),
109  .priv_size = sizeof(ASNSContext),
110  .priv_class = &asetnsamples_class,
113  .activate = activate,
115  .process_command = ff_filter_process_command,
116 };
av_samples_copy
int av_samples_copy(uint8_t *const *dst, uint8_t *const *src, int dst_offset, int src_offset, int nb_samples, int nb_channels, enum AVSampleFormat sample_fmt)
Copy samples from src to dst.
Definition: samplefmt.c:222
ff_get_audio_buffer
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
Definition: audio.c:97
AVERROR
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
opt.h
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1018
FFERROR_NOT_READY
return FFERROR_NOT_READY
Definition: filter_design.txt:204
inlink
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
Definition: filter_design.txt:212
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:160
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:375
av_samples_set_silence
int av_samples_set_silence(uint8_t *const *audio_data, int offset, int nb_samples, int nb_channels, enum AVSampleFormat sample_fmt)
Fill an audio buffer with silence.
Definition: samplefmt.c:246
AVOption
AVOption.
Definition: opt.h:346
activate
static int activate(AVFilterContext *ctx)
Definition: af_asetnsamples.c:53
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:170
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:313
FF_FILTER_FORWARD_STATUS_BACK
#define FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink)
Forward the status on an output link to an input link.
Definition: filters.h:199
ff_af_asetnsamples
const AVFilter ff_af_asetnsamples
Definition: af_asetnsamples.c:106
ff_inlink_consume_frame
int ff_inlink_consume_frame(AVFilterLink *link, AVFrame **rframe)
Take a frame from the link's FIFO and update the link's stats.
Definition: avfilter.c:1445
asetnsamples_options
static const AVOption asetnsamples_options[]
Definition: af_asetnsamples.c:43
AVFrame::ch_layout
AVChannelLayout ch_layout
Channel layout of the audio data.
Definition: frame.h:776
ASNSContext::pad
int pad
Definition: af_asetnsamples.c:37
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(asetnsamples)
s
#define s(width, name)
Definition: cbs_vp9.c:198
filters.h
ctx
AVFormatContext * ctx
Definition: movenc.c:48
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:182
frame
static AVFrame * frame
Definition: demux_decode.c:54
FLAGS
#define FLAGS
Definition: af_asetnsamples.c:41
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
ff_inlink_consume_samples
int ff_inlink_consume_samples(AVFilterLink *link, unsigned min, unsigned max, AVFrame **rframe)
Take samples from the link's FIFO and update the link's stats.
Definition: avfilter.c:1465
NULL
#define NULL
Definition: coverity.c:32
av_frame_copy_props
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:709
ff_audio_default_filterpad
const AVFilterPad ff_audio_default_filterpad[1]
An AVFilterPad array whose only entry has name "default" and is of type AVMEDIA_TYPE_AUDIO.
Definition: audio.c:33
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:106
ASNSContext::nb_out_samples
int nb_out_samples
how many samples to output
Definition: af_asetnsamples.c:36
AVFrame::format
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames,...
Definition: frame.h:462
ff_filter_process_command
int ff_filter_process_command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
Generic processing of user supplied commands that are set in the same way as the filter options.
Definition: avfilter.c:890
FF_FILTER_FORWARD_WANTED
FF_FILTER_FORWARD_WANTED(outlink, inlink)
internal.h
ASNSContext
Definition: af_asetnsamples.c:34
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:455
AVFrame::extended_data
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:436
ff_inlink_queued_samples
int ff_inlink_queued_samples(AVFilterLink *link)
Definition: avfilter.c:1420
AVFilter
Filter definition.
Definition: avfilter.h:166
ret
ret
Definition: filter_design.txt:187
OFFSET
#define OFFSET(x)
Definition: af_asetnsamples.c:40
channel_layout.h
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:235
avfilter.h
AVFilterContext
An instance of a filter.
Definition: avfilter.h:407
audio.h
FF_FILTER_FORWARD_STATUS
FF_FILTER_FORWARD_STATUS(inlink, outlink)
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:251
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:183
AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL
#define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL
Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will have its filter_frame() c...
Definition: avfilter.h:155
ff_filter_set_ready
void ff_filter_set_ready(AVFilterContext *filter, unsigned priority)
Mark a filter ready and schedule it for activation.
Definition: avfilter.c:234