FFmpeg
af_dcshift.c
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1 /*
2  * Copyright (c) 2000 Chris Ausbrooks <weed@bucket.pp.ualr.edu>
3  * Copyright (c) 2000 Fabien COELHO <fabien@coelho.net>
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 #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 DCShiftContext {
29  const AVClass *class;
30  double dcshift;
32  double limitergain;
34 
35 #define OFFSET(x) offsetof(DCShiftContext, x)
36 #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
37 
38 static const AVOption dcshift_options[] = {
39  { "shift", "set DC shift", OFFSET(dcshift), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, A },
40  { "limitergain", "set limiter gain", OFFSET(limitergain), AV_OPT_TYPE_DOUBLE, {.dbl=0}, 0, 1, A },
41  { NULL }
42 };
43 
44 AVFILTER_DEFINE_CLASS(dcshift);
45 
47 {
48  DCShiftContext *s = ctx->priv;
49 
50  s->limiterthreshold = INT32_MAX * (1.0 - (fabs(s->dcshift) - s->limitergain));
51 
52  return 0;
53 }
54 
56 {
59  static const enum AVSampleFormat sample_fmts[] = {
61  };
62  int ret;
63 
65  if (!layouts)
66  return AVERROR(ENOMEM);
68  if (ret < 0)
69  return ret;
70 
72  if (!formats)
73  return AVERROR(ENOMEM);
75  if (ret < 0)
76  return ret;
77 
79  if (!formats)
80  return AVERROR(ENOMEM);
82 }
83 
85 {
86  AVFilterContext *ctx = inlink->dst;
87  AVFilterLink *outlink = ctx->outputs[0];
88  AVFrame *out;
89  DCShiftContext *s = ctx->priv;
90  int i, j;
91  double dcshift = s->dcshift;
92 
93  if (av_frame_is_writable(in)) {
94  out = in;
95  } else {
96  out = ff_get_audio_buffer(outlink, in->nb_samples);
97  if (!out) {
98  av_frame_free(&in);
99  return AVERROR(ENOMEM);
100  }
102  }
103 
104  if (s->limitergain > 0) {
105  for (i = 0; i < inlink->channels; i++) {
106  const int32_t *src = (int32_t *)in->extended_data[i];
107  int32_t *dst = (int32_t *)out->extended_data[i];
108 
109  for (j = 0; j < in->nb_samples; j++) {
110  double d;
111 
112  d = src[j];
113 
114  if (d > s->limiterthreshold && dcshift > 0) {
115  d = (d - s->limiterthreshold) * s->limitergain /
116  (INT32_MAX - s->limiterthreshold) +
117  s->limiterthreshold + dcshift;
118  } else if (d < -s->limiterthreshold && dcshift < 0) {
119  d = (d + s->limiterthreshold) * s->limitergain /
120  (INT32_MAX - s->limiterthreshold) -
121  s->limiterthreshold + dcshift;
122  } else {
123  d = dcshift * INT32_MAX + d;
124  }
125 
126  dst[j] = av_clipl_int32(d);
127  }
128  }
129  } else {
130  for (i = 0; i < inlink->channels; i++) {
131  const int32_t *src = (int32_t *)in->extended_data[i];
132  int32_t *dst = (int32_t *)out->extended_data[i];
133 
134  for (j = 0; j < in->nb_samples; j++) {
135  double d = dcshift * (INT32_MAX + 1.) + src[j];
136 
137  dst[j] = av_clipl_int32(d);
138  }
139  }
140  }
141 
142  if (out != in)
143  av_frame_free(&in);
144  return ff_filter_frame(outlink, out);
145 }
146 static const AVFilterPad dcshift_inputs[] = {
147  {
148  .name = "default",
149  .type = AVMEDIA_TYPE_AUDIO,
150  .filter_frame = filter_frame,
151  },
152  { NULL }
153 };
154 
155 static const AVFilterPad dcshift_outputs[] = {
156  {
157  .name = "default",
158  .type = AVMEDIA_TYPE_AUDIO,
159  },
160  { NULL }
161 };
162 
164  .name = "dcshift",
165  .description = NULL_IF_CONFIG_SMALL("Apply a DC shift to the audio."),
166  .query_formats = query_formats,
167  .priv_size = sizeof(DCShiftContext),
168  .priv_class = &dcshift_class,
169  .init = init,
173 };
formats
formats
Definition: signature.h:48
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:86
AVFilterChannelLayouts
A list of supported channel layouts.
Definition: formats.h:86
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_make_format_list
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:286
out
FILE * out
Definition: movenc.c:54
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1094
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:926
layouts
enum MovChannelLayoutTag * layouts
Definition: mov_chan.c:434
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:204
ff_all_channel_counts
AVFilterChannelLayouts * ff_all_channel_counts(void)
Construct an AVFilterChannelLayouts coding for any channel layout, with known or unknown disposition.
Definition: formats.c:436
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:324
AVOption
AVOption.
Definition: opt.h:248
AV_SAMPLE_FMT_S32P
@ AV_SAMPLE_FMT_S32P
signed 32 bits, planar
Definition: samplefmt.h:68
DCShiftContext::limiterthreshold
double limiterthreshold
Definition: af_dcshift.c:31
DCShiftContext::limitergain
double limitergain
Definition: af_dcshift.c:32
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:149
OFFSET
#define OFFSET(x)
Definition: af_dcshift.c:35
dcshift_outputs
static const AVFilterPad dcshift_outputs[]
Definition: af_dcshift.c:155
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:65
samplefmt.h
DCShiftContext::dcshift
double dcshift
Definition: af_dcshift.c:30
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:54
av_cold
#define av_cold
Definition: attributes.h:90
inputs
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
Definition: filter_design.txt:243
ff_set_common_formats
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:587
s
#define s(width, name)
Definition: cbs_vp9.c:257
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:227
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
outputs
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
ctx
AVFormatContext * ctx
Definition: movenc.c:48
A
#define A
Definition: af_dcshift.c:36
int32_t
int32_t
Definition: audio_convert.c:194
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
fabs
static __device__ float fabs(float a)
Definition: cuda_runtime.h:182
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:659
src
#define src
Definition: vp8dsp.c:255
init
static av_cold int init(AVFilterContext *ctx)
Definition: af_dcshift.c:46
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:117
av_clipl_int32
#define av_clipl_int32
Definition: common.h:140
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
av_frame_is_writable
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:595
internal.h
AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:126
ff_af_dcshift
AVFilter ff_af_dcshift
Definition: af_dcshift.c:163
in
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(const int16_t *) pi >> 8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(const int32_t *) pi >> 24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(const float *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(const float *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(const float *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(const double *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(const double *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(const double *) pi *(1U<< 31)))) #define SET_CONV_FUNC_GROUP(ofmt, ifmt) static void set_generic_function(AudioConvert *ac) { } void ff_audio_convert_free(AudioConvert **ac) { if(! *ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);} AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, int channels, int sample_rate, int apply_map) { AudioConvert *ac;int in_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) return NULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method !=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt) > 2) { ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc) { av_free(ac);return NULL;} return ac;} in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar) { ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar ? ac->channels :1;} else if(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;else ac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);return ac;} int ff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in) { int use_generic=1;int len=in->nb_samples;int p;if(ac->dc) { av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
Definition: audio_convert.c:326
i
int i
Definition: input.c:407
query_formats
static int query_formats(AVFilterContext *ctx)
Definition: af_dcshift.c:55
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:60
AVFilter
Filter definition.
Definition: avfilter.h:145
ret
ret
Definition: filter_design.txt:187
ff_all_samplerates
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:421
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_dcshift.c:84
avfilter.h
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(dcshift)
AVFilterContext
An instance of a filter.
Definition: avfilter.h:341
audio.h
d
d
Definition: ffmpeg_filter.c:158
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
ff_set_common_samplerates
int ff_set_common_samplerates(AVFilterContext *ctx, AVFilterFormats *samplerates)
Definition: formats.c:575
dcshift_options
static const AVOption dcshift_options[]
Definition: af_dcshift.c:38
dcshift_inputs
static const AVFilterPad dcshift_inputs[]
Definition: af_dcshift.c:146
DCShiftContext
Definition: af_dcshift.c:28
ff_set_common_channel_layouts
int ff_set_common_channel_layouts(AVFilterContext *ctx, AVFilterChannelLayouts *channel_layouts)
A helper for query_formats() which sets all links to the same list of channel layouts/sample rates.
Definition: formats.c:568