FFmpeg  4.0
af_crossfeed.c
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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 
20 #include "libavutil/opt.h"
21 #include "avfilter.h"
22 #include "audio.h"
23 #include "formats.h"
24 
25 typedef struct CrossfeedContext {
26  const AVClass *class;
27 
28  double range;
29  double strength;
30  double level_in;
31  double level_out;
32 
33  double a0, a1, a2;
34  double b0, b1, b2;
35 
36  double i1, i2;
37  double o1, o2;
39 
41 {
44  int ret;
45 
46  if ((ret = ff_add_format (&formats, AV_SAMPLE_FMT_DBL )) < 0 ||
47  (ret = ff_set_common_formats (ctx , formats )) < 0 ||
48  (ret = ff_add_channel_layout (&layout , AV_CH_LAYOUT_STEREO)) < 0 ||
49  (ret = ff_set_common_channel_layouts (ctx , layout )) < 0 ||
50  (ret = ff_set_common_samplerates (ctx , ff_all_samplerates())) < 0)
51  return ret;
52 
53  return 0;
54 }
55 
56 static int config_input(AVFilterLink *inlink)
57 {
58  AVFilterContext *ctx = inlink->dst;
59  CrossfeedContext *s = ctx->priv;
60  double A = exp(s->strength * -30 / 40 * log(10.));
61  double w0 = 2 * M_PI * (1. - s->range) * 2100 / inlink->sample_rate;
62  double alpha;
63 
64  alpha = sin(w0) / 2 * sqrt(2 * (1 / 0.5 - 1) + 2);
65 
66  s->a0 = (A + 1) + (A - 1) * cos(w0) + 2 * sqrt(A) * alpha;
67  s->a1 = -2 * ((A - 1) + (A + 1) * cos(w0));
68  s->a2 = (A + 1) + (A - 1) * cos(w0) - 2 * sqrt(A) * alpha;
69  s->b0 = A * ((A + 1) - (A - 1) * cos(w0) + 2 * sqrt(A) * alpha);
70  s->b1 = 2 * A * ((A - 1) - (A + 1) * cos(w0));
71  s->b2 = A * ((A + 1) - (A - 1) * cos(w0) - 2 * sqrt(A) * alpha);
72 
73  s->a1 /= s->a0;
74  s->a2 /= s->a0;
75  s->b0 /= s->a0;
76  s->b1 /= s->a0;
77  s->b2 /= s->a0;
78 
79  return 0;
80 }
81 
82 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
83 {
84  AVFilterContext *ctx = inlink->dst;
85  AVFilterLink *outlink = ctx->outputs[0];
86  CrossfeedContext *s = ctx->priv;
87  const double *src = (const double *)in->data[0];
88  const double level_in = s->level_in;
89  const double level_out = s->level_out;
90  const double b0 = s->b0;
91  const double b1 = s->b1;
92  const double b2 = s->b2;
93  const double a1 = s->a1;
94  const double a2 = s->a2;
95  AVFrame *out;
96  double *dst;
97  int n;
98 
99  if (av_frame_is_writable(in)) {
100  out = in;
101  } else {
102  out = ff_get_audio_buffer(outlink, in->nb_samples);
103  if (!out) {
104  av_frame_free(&in);
105  return AVERROR(ENOMEM);
106  }
108  }
109  dst = (double *)out->data[0];
110 
111  for (n = 0; n < out->nb_samples; n++, src += 2, dst += 2) {
112  double mid = (src[0] + src[1]) * level_in * .5;
113  double side = (src[0] - src[1]) * level_in * .5;
114  double oside = side * b0 + s->i1 * b1 + s->i2 * b2 - s->o1 * a1 - s->o2 * a2;
115 
116  s->i2 = s->i1;
117  s->i1 = side;
118  s->o2 = s->o1;
119  s->o1 = oside;
120 
121  dst[0] = (mid + oside) * level_out;
122  dst[1] = (mid - oside) * level_out;
123  }
124 
125  if (out != in)
126  av_frame_free(&in);
127  return ff_filter_frame(outlink, out);
128 }
129 
130 #define OFFSET(x) offsetof(CrossfeedContext, x)
131 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
132 
133 static const AVOption crossfeed_options[] = {
134  { "strength", "set crossfeed strength", OFFSET(strength), AV_OPT_TYPE_DOUBLE, {.dbl=.2}, 0, 1, FLAGS },
135  { "range", "set soundstage wideness", OFFSET(range), AV_OPT_TYPE_DOUBLE, {.dbl=.5}, 0, 1, FLAGS },
136  { "level_in", "set level in", OFFSET(level_in), AV_OPT_TYPE_DOUBLE, {.dbl=.9}, 0, 1, FLAGS },
137  { "level_out", "set level out", OFFSET(level_out), AV_OPT_TYPE_DOUBLE, {.dbl=1.}, 0, 1, FLAGS },
138  { NULL }
139 };
140 
141 AVFILTER_DEFINE_CLASS(crossfeed);
142 
143 static const AVFilterPad inputs[] = {
144  {
145  .name = "default",
146  .type = AVMEDIA_TYPE_AUDIO,
147  .filter_frame = filter_frame,
148  .config_props = config_input,
149  },
150  { NULL }
151 };
152 
153 static const AVFilterPad outputs[] = {
154  {
155  .name = "default",
156  .type = AVMEDIA_TYPE_AUDIO,
157  },
158  { NULL }
159 };
160 
162  .name = "crossfeed",
163  .description = NULL_IF_CONFIG_SMALL("Apply headphone crossfeed filter."),
164  .query_formats = query_formats,
165  .priv_size = sizeof(CrossfeedContext),
166  .priv_class = &crossfeed_class,
167  .inputs = inputs,
168  .outputs = outputs,
169 };
#define NULL
Definition: coverity.c:32
int ff_set_common_channel_layouts(AVFilterContext *ctx, AVFilterChannelLayouts *layouts)
A helper for query_formats() which sets all links to the same list of channel layouts/sample rates...
Definition: formats.c:549
const char * s
Definition: avisynth_c.h:768
static float alpha(float a)
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
AVOption.
Definition: opt.h:246
static int config_input(AVFilterLink *inlink)
Definition: af_crossfeed.c:56
Main libavfilter public API header.
static const AVOption crossfeed_options[]
Definition: af_crossfeed.c:133
#define FLAGS
Definition: af_crossfeed.c:131
#define AV_CH_LAYOUT_STEREO
#define src
Definition: vp8dsp.c:254
const char * name
Pad name.
Definition: internal.h:60
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_crossfeed.c:82
AVOptions.
static const AVFilterPad inputs[]
Definition: af_crossfeed.c:143
#define A(x)
Definition: vp56_arith.h:28
static const AVFilterPad outputs[]
Definition: af_crossfeed.c:153
A filter pad used for either input or output.
Definition: internal.h:54
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:568
int ff_add_channel_layout(AVFilterChannelLayouts **l, uint64_t channel_layout)
Definition: formats.c:343
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
#define AVERROR(e)
Definition: error.h:43
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 * priv
private data for use by the filter
Definition: avfilter.h:353
AVFILTER_DEFINE_CLASS(crossfeed)
int ff_add_format(AVFilterFormats **avff, int64_t fmt)
Add fmt to the list of media formats contained in *avff.
Definition: formats.c:337
int8_t exp
Definition: eval.c:72
audio channel layout utility functions
AVFormatContext * ctx
Definition: movenc.c:48
int n
Definition: avisynth_c.h:684
if(ret< 0)
Definition: vf_mcdeint.c:279
A list of supported channel layouts.
Definition: formats.h:85
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:592
static int query_formats(AVFilterContext *ctx)
Definition: af_crossfeed.c:40
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)\", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
const char * name
Filter name.
Definition: avfilter.h:148
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:395
#define OFFSET(x)
Definition: af_crossfeed.c:130
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:232
AVFilter ff_af_crossfeed
Definition: af_crossfeed.c:161
A list of supported formats for one end of a filter link.
Definition: formats.h:64
uint64_t layout
An instance of a filter.
Definition: avfilter.h:338
FILE * out
Definition: movenc.c:54
#define M_PI
Definition: mathematics.h:52
formats
Definition: signature.h:48
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:284
for(j=16;j >0;--j)
int ff_set_common_samplerates(AVFilterContext *ctx, AVFilterFormats *samplerates)
Definition: formats.c:556
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:652