FFmpeg
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/ffmath.h"
21 #include "libavutil/opt.h"
22 #include "avfilter.h"
23 #include "audio.h"
24 #include "formats.h"
25 
26 typedef struct CrossfeedContext {
27  const AVClass *class;
28 
29  double range;
30  double strength;
31  double slope;
32  double level_in;
33  double level_out;
34 
35  double a0, a1, a2;
36  double b0, b1, b2;
37 
38  double w1, w2;
40 
42 {
45  int ret;
46 
47  if ((ret = ff_add_format (&formats, AV_SAMPLE_FMT_DBL )) < 0 ||
48  (ret = ff_set_common_formats (ctx , formats )) < 0 ||
52  return ret;
53 
54  return 0;
55 }
56 
58 {
59  AVFilterContext *ctx = inlink->dst;
60  CrossfeedContext *s = ctx->priv;
61  double A = ff_exp10(s->strength * -30 / 40);
62  double w0 = 2 * M_PI * (1. - s->range) * 2100 / inlink->sample_rate;
63  double alpha;
64 
65  alpha = sin(w0) / 2 * sqrt((A + 1 / A) * (1 / s->slope - 1) + 2);
66 
67  s->a0 = (A + 1) + (A - 1) * cos(w0) + 2 * sqrt(A) * alpha;
68  s->a1 = -2 * ((A - 1) + (A + 1) * cos(w0));
69  s->a2 = (A + 1) + (A - 1) * cos(w0) - 2 * sqrt(A) * alpha;
70  s->b0 = A * ((A + 1) - (A - 1) * cos(w0) + 2 * sqrt(A) * alpha);
71  s->b1 = 2 * A * ((A - 1) - (A + 1) * cos(w0));
72  s->b2 = A * ((A + 1) - (A - 1) * cos(w0) - 2 * sqrt(A) * alpha);
73 
74  s->a1 /= s->a0;
75  s->a2 /= s->a0;
76  s->b0 /= s->a0;
77  s->b1 /= s->a0;
78  s->b2 /= s->a0;
79 
80  return 0;
81 }
82 
84 {
85  AVFilterContext *ctx = inlink->dst;
86  AVFilterLink *outlink = ctx->outputs[0];
87  CrossfeedContext *s = ctx->priv;
88  const double *src = (const double *)in->data[0];
89  const double level_in = s->level_in;
90  const double level_out = s->level_out;
91  const double b0 = s->b0;
92  const double b1 = s->b1;
93  const double b2 = s->b2;
94  const double a1 = -s->a1;
95  const double a2 = -s->a2;
96  AVFrame *out;
97  double *dst;
98  int n;
99 
100  if (av_frame_is_writable(in)) {
101  out = in;
102  } else {
103  out = ff_get_audio_buffer(outlink, in->nb_samples);
104  if (!out) {
105  av_frame_free(&in);
106  return AVERROR(ENOMEM);
107  }
109  }
110  dst = (double *)out->data[0];
111 
112  for (n = 0; n < out->nb_samples; n++, src += 2, dst += 2) {
113  double mid = (src[0] + src[1]) * level_in * .5;
114  double side = (src[0] - src[1]) * level_in * .5;
115  double oside = side * b0 + s->w1;
116 
117  s->w1 = b1 * side + s->w2 + a1 * oside;
118  s->w2 = b2 * side + a2 * oside;
119 
120  if (ctx->is_disabled) {
121  dst[0] = src[0];
122  dst[1] = src[1];
123  } else {
124  dst[0] = (mid + oside) * level_out;
125  dst[1] = (mid - oside) * level_out;
126  }
127  }
128 
129  if (out != in)
130  av_frame_free(&in);
131  return ff_filter_frame(outlink, out);
132 }
133 
134 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
135  char *res, int res_len, int flags)
136 {
137  int ret;
138 
139  ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);
140  if (ret < 0)
141  return ret;
142 
143  return config_input(ctx->inputs[0]);
144 }
145 
146 #define OFFSET(x) offsetof(CrossfeedContext, x)
147 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
148 
149 static const AVOption crossfeed_options[] = {
150  { "strength", "set crossfeed strength", OFFSET(strength), AV_OPT_TYPE_DOUBLE, {.dbl=.2}, 0, 1, FLAGS },
151  { "range", "set soundstage wideness", OFFSET(range), AV_OPT_TYPE_DOUBLE, {.dbl=.5}, 0, 1, FLAGS },
152  { "slope", "set curve slope", OFFSET(slope), AV_OPT_TYPE_DOUBLE, {.dbl=.5}, .01, 1, FLAGS },
153  { "level_in", "set level in", OFFSET(level_in), AV_OPT_TYPE_DOUBLE, {.dbl=.9}, 0, 1, FLAGS },
154  { "level_out", "set level out", OFFSET(level_out), AV_OPT_TYPE_DOUBLE, {.dbl=1.}, 0, 1, FLAGS },
155  { NULL }
156 };
157 
158 AVFILTER_DEFINE_CLASS(crossfeed);
159 
160 static const AVFilterPad inputs[] = {
161  {
162  .name = "default",
163  .type = AVMEDIA_TYPE_AUDIO,
164  .filter_frame = filter_frame,
165  .config_props = config_input,
166  },
167  { NULL }
168 };
169 
170 static const AVFilterPad outputs[] = {
171  {
172  .name = "default",
173  .type = AVMEDIA_TYPE_AUDIO,
174  },
175  { NULL }
176 };
177 
179  .name = "crossfeed",
180  .description = NULL_IF_CONFIG_SMALL("Apply headphone crossfeed filter."),
181  .query_formats = query_formats,
182  .priv_size = sizeof(CrossfeedContext),
183  .priv_class = &crossfeed_class,
184  .inputs = inputs,
185  .outputs = outputs,
188 };
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:85
ff_exp10
static av_always_inline double ff_exp10(double x)
Compute 10^x for floating point values.
Definition: ffmath.h:42
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
CrossfeedContext::a1
double a1
Definition: af_crossfeed.c:35
CrossfeedContext::strength
double strength
Definition: af_crossfeed.c:30
out
FILE * out
Definition: movenc.c:54
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_crossfeed.c:83
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:978
process_command
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
Definition: af_crossfeed.c:134
inputs
static const AVFilterPad inputs[]
Definition: af_crossfeed.c:160
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:112
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_crossfeed.c:57
CrossfeedContext
Definition: af_crossfeed.c:26
AVOption
AVOption.
Definition: opt.h:247
CrossfeedContext::w1
double w1
Definition: af_crossfeed.c:38
CrossfeedContext::level_in
double level_in
Definition: af_crossfeed.c:32
CrossfeedContext::b1
double b1
Definition: af_crossfeed.c:36
crossfeed_options
static const AVOption crossfeed_options[]
Definition: af_crossfeed.c:149
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:149
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:317
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:64
formats.h
A
#define A(x)
Definition: vp56_arith.h:28
b1
static double b1(void *priv, double x, double y)
Definition: vf_xfade.c:1665
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(crossfeed)
AV_CH_LAYOUT_STEREO
#define AV_CH_LAYOUT_STEREO
Definition: channel_layout.h:91
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:54
FLAGS
#define FLAGS
Definition: af_crossfeed.c:147
a1
#define a1
Definition: regdef.h:47
CrossfeedContext::w2
double w2
Definition: af_crossfeed.c:38
ff_af_crossfeed
const AVFilter ff_af_crossfeed
Definition: af_crossfeed.c:178
CrossfeedContext::a2
double a2
Definition: af_crossfeed.c:35
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:580
ff_add_channel_layout
int ff_add_channel_layout(AVFilterChannelLayouts **l, uint64_t channel_layout)
Definition: formats.c:331
s
#define s(width, name)
Definition: cbs_vp9.c:257
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:226
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
ctx
AVFormatContext * ctx
Definition: movenc.c:48
CrossfeedContext::b2
double b2
Definition: af_crossfeed.c:36
if
if(ret)
Definition: filter_design.txt:179
CrossfeedContext::a0
double a0
Definition: af_crossfeed.c:35
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
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:537
src
#define src
Definition: vp8dsp.c:255
ff_add_format
int ff_add_format(AVFilterFormats **avff, int64_t fmt)
Add fmt to the list of media formats contained in *avff.
Definition: formats.c:325
outputs
static const AVFilterPad outputs[]
Definition: af_crossfeed.c:170
CrossfeedContext::range
double range
Definition: af_crossfeed.c:29
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
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:116
av_frame_is_writable
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:473
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:842
b2
static double b2(void *priv, double x, double y)
Definition: vf_xfade.c:1666
M_PI
#define M_PI
Definition: mathematics.h:52
layout
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 layout
Definition: filter_design.txt:18
query_formats
static int query_formats(AVFilterContext *ctx)
Definition: af_crossfeed.c:41
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:369
CrossfeedContext::level_out
double level_out
Definition: af_crossfeed.c:33
a2
#define a2
Definition: regdef.h:48
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:414
channel_layout.h
avfilter.h
ffmath.h
CrossfeedContext::slope
double slope
Definition: af_crossfeed.c:31
AVFilterContext
An instance of a filter.
Definition: avfilter.h:333
audio.h
OFFSET
#define OFFSET(x)
Definition: af_crossfeed.c:146
CrossfeedContext::b0
double b0
Definition: af_crossfeed.c:36
alpha
static const int16_t alpha[]
Definition: ilbcdata.h:55
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:134
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:568
b0
static double b0(void *priv, double x, double y)
Definition: vf_xfade.c:1664
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:64
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:561