FFmpeg
af_aexciter.c
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1 /*
2  * Copyright (c) Markus Schmidt and Christian Holschuh
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 GNU
14  * 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 #include "libavutil/mem.h"
22 #include "libavutil/opt.h"
23 #include "avfilter.h"
24 #include "internal.h"
25 #include "audio.h"
26 
27 typedef struct ChannelParams {
29  double rdrive, rbdr, kpa, kpb, kna, knb, ap,
30  an, imr, kc, srct, sq, pwrq;
31  double prev_med, prev_out;
32 
33  double hp[5], lp[5];
34  double hw[4][2], lw[2][2];
36 
37 typedef struct AExciterContext {
38  const AVClass *class;
39 
40  double level_in;
41  double level_out;
42  double amount;
43  double drive;
44  double blend;
45  double freq;
46  double ceil;
47  int listen;
48 
51 
52 #define OFFSET(x) offsetof(AExciterContext, x)
53 #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
54 
55 static const AVOption aexciter_options[] = {
56  { "level_in", "set level in", OFFSET(level_in), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 64, A },
57  { "level_out", "set level out", OFFSET(level_out), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 64, A },
58  { "amount", "set amount", OFFSET(amount), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 64, A },
59  { "drive", "set harmonics", OFFSET(drive), AV_OPT_TYPE_DOUBLE, {.dbl=8.5}, 0.1, 10, A },
60  { "blend", "set blend harmonics", OFFSET(blend), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -10, 10, A },
61  { "freq", "set scope", OFFSET(freq), AV_OPT_TYPE_DOUBLE, {.dbl=7500}, 2000, 12000, A },
62  { "ceil", "set ceiling", OFFSET(ceil), AV_OPT_TYPE_DOUBLE, {.dbl=9999}, 9999, 20000, A },
63  { "listen", "enable listen mode", OFFSET(listen), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, A },
64  { NULL }
65 };
66 
67 AVFILTER_DEFINE_CLASS(aexciter);
68 
69 static inline double M(double x)
70 {
71  return (fabs(x) > 0.00000001) ? x : 0.0;
72 }
73 
74 static inline double D(double x)
75 {
76  x = fabs(x);
77 
78  return (x > 0.00000001) ? sqrt(x) : 0.0;
79 }
80 
81 static void set_params(ChannelParams *p,
82  double blend, double drive,
83  double srate, double freq,
84  double ceil)
85 {
86  double a0, a1, a2, b0, b1, b2, w0, alpha;
87 
88  p->rdrive = 12.0 / drive;
89  p->rbdr = p->rdrive / (10.5 - blend) * 780.0 / 33.0;
90  p->kpa = D(2.0 * (p->rdrive*p->rdrive) - 1.0) + 1.0;
91  p->kpb = (2.0 - p->kpa) / 2.0;
92  p->ap = ((p->rdrive*p->rdrive) - p->kpa + 1.0) / 2.0;
93  p->kc = p->kpa / D(2.0 * D(2.0 * (p->rdrive*p->rdrive) - 1.0) - 2.0 * p->rdrive*p->rdrive);
94 
95  p->srct = (0.1 * srate) / (0.1 * srate + 1.0);
96  p->sq = p->kc*p->kc + 1.0;
97  p->knb = -1.0 * p->rbdr / D(p->sq);
98  p->kna = 2.0 * p->kc * p->rbdr / D(p->sq);
99  p->an = p->rbdr*p->rbdr / p->sq;
100  p->imr = 2.0 * p->knb + D(2.0 * p->kna + 4.0 * p->an - 1.0);
101  p->pwrq = 2.0 / (p->imr + 1.0);
102 
103  w0 = 2 * M_PI * freq / srate;
104  alpha = sin(w0) / (2. * 0.707);
105  a0 = 1 + alpha;
106  a1 = -2 * cos(w0);
107  a2 = 1 - alpha;
108  b0 = (1 + cos(w0)) / 2;
109  b1 = -(1 + cos(w0));
110  b2 = (1 + cos(w0)) / 2;
111 
112  p->hp[0] =-a1 / a0;
113  p->hp[1] =-a2 / a0;
114  p->hp[2] = b0 / a0;
115  p->hp[3] = b1 / a0;
116  p->hp[4] = b2 / a0;
117 
118  w0 = 2 * M_PI * ceil / srate;
119  alpha = sin(w0) / (2. * 0.707);
120  a0 = 1 + alpha;
121  a1 = -2 * cos(w0);
122  a2 = 1 - alpha;
123  b0 = (1 - cos(w0)) / 2;
124  b1 = 1 - cos(w0);
125  b2 = (1 - cos(w0)) / 2;
126 
127  p->lp[0] =-a1 / a0;
128  p->lp[1] =-a2 / a0;
129  p->lp[2] = b0 / a0;
130  p->lp[3] = b1 / a0;
131  p->lp[4] = b2 / a0;
132 }
133 
134 static double bprocess(double in, const double *const c,
135  double *w1, double *w2)
136 {
137  double out = c[2] * in + *w1;
138 
139  *w1 = c[3] * in + *w2 + c[0] * out;
140  *w2 = c[4] * in + c[1] * out;
141 
142  return out;
143 }
144 
145 static double distortion_process(AExciterContext *s, ChannelParams *p, double in)
146 {
147  double proc = in, med;
148 
149  proc = bprocess(proc, p->hp, &p->hw[0][0], &p->hw[0][1]);
150  proc = bprocess(proc, p->hp, &p->hw[1][0], &p->hw[1][1]);
151 
152  if (proc >= 0.0) {
153  med = (D(p->ap + proc * (p->kpa - proc)) + p->kpb) * p->pwrq;
154  } else {
155  med = (D(p->an - proc * (p->kna + proc)) + p->knb) * p->pwrq * -1.0;
156  }
157 
158  proc = p->srct * (med - p->prev_med + p->prev_out);
159  p->prev_med = M(med);
160  p->prev_out = M(proc);
161 
162  proc = bprocess(proc, p->hp, &p->hw[2][0], &p->hw[2][1]);
163  proc = bprocess(proc, p->hp, &p->hw[3][0], &p->hw[3][1]);
164 
165  if (s->ceil >= 10000.) {
166  proc = bprocess(proc, p->lp, &p->lw[0][0], &p->lw[0][1]);
167  proc = bprocess(proc, p->lp, &p->lw[1][0], &p->lw[1][1]);
168  }
169 
170  return proc;
171 }
172 
174 {
175  AVFilterContext *ctx = inlink->dst;
176  AExciterContext *s = ctx->priv;
177  AVFilterLink *outlink = ctx->outputs[0];
178  AVFrame *out;
179  const double *src = (const double *)in->data[0];
180  const double level_in = s->level_in;
181  const double level_out = s->level_out;
182  const double amount = s->amount;
183  const double listen = 1.0 - s->listen;
184  double *dst;
185 
186  if (av_frame_is_writable(in)) {
187  out = in;
188  } else {
190  if (!out) {
191  av_frame_free(&in);
192  return AVERROR(ENOMEM);
193  }
195  }
196 
197  dst = (double *)out->data[0];
198  for (int n = 0; n < in->nb_samples; n++) {
199  for (int c = 0; c < inlink->ch_layout.nb_channels; c++) {
200  double sample = src[c] * level_in;
201 
202  sample = distortion_process(s, &s->cp[c], sample);
203  sample = sample * amount + listen * src[c];
204 
205  sample *= level_out;
206  if (ctx->is_disabled)
207  dst[c] = src[c];
208  else
209  dst[c] = sample;
210  }
211 
212  src += inlink->ch_layout.nb_channels;
213  dst += inlink->ch_layout.nb_channels;
214  }
215 
216  if (in != out)
217  av_frame_free(&in);
218 
219  return ff_filter_frame(outlink, out);
220 }
221 
223 {
224  AExciterContext *s = ctx->priv;
225 
226  av_freep(&s->cp);
227 }
228 
230 {
231  AVFilterContext *ctx = inlink->dst;
232  AExciterContext *s = ctx->priv;
233 
234  if (!s->cp)
235  s->cp = av_calloc(inlink->ch_layout.nb_channels, sizeof(*s->cp));
236  if (!s->cp)
237  return AVERROR(ENOMEM);
238 
239  for (int i = 0; i < inlink->ch_layout.nb_channels; i++)
240  set_params(&s->cp[i], s->blend, s->drive, inlink->sample_rate,
241  s->freq, s->ceil);
242 
243  return 0;
244 }
245 
246 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
247  char *res, int res_len, int flags)
248 {
249  AVFilterLink *inlink = ctx->inputs[0];
250  int ret;
251 
252  ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);
253  if (ret < 0)
254  return ret;
255 
256  return config_input(inlink);
257 }
258 
260  {
261  .name = "default",
262  .type = AVMEDIA_TYPE_AUDIO,
263  .config_props = config_input,
264  .filter_frame = filter_frame,
265  },
266 };
267 
269  .name = "aexciter",
270  .description = NULL_IF_CONFIG_SMALL("Enhance high frequency part of audio."),
271  .priv_size = sizeof(AExciterContext),
272  .priv_class = &aexciter_class,
273  .uninit = uninit,
277  .process_command = process_command,
279 };
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
AExciterContext
Definition: af_aexciter.c:37
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
out
FILE * out
Definition: movenc.c:55
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1015
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_aexciter.c:173
A
#define A
Definition: af_aexciter.c:53
ChannelParams::hw
double hw[4][2]
Definition: af_aexciter.c:34
FILTER_SINGLE_SAMPLEFMT
#define FILTER_SINGLE_SAMPLEFMT(sample_fmt_)
Definition: internal.h:175
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
ChannelParams::srct
double srct
Definition: af_aexciter.c:30
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:374
AExciterContext::drive
double drive
Definition: af_aexciter.c:43
AVOption
AVOption.
Definition: opt.h:357
ChannelParams::prev_med
double prev_med
Definition: af_aexciter.c:31
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:170
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:395
ChannelParams::pwrq
double pwrq
Definition: af_aexciter.c:30
b1
static double b1(void *priv, double x, double y)
Definition: vf_xfade.c:2035
AExciterContext::ceil
double ceil
Definition: af_aexciter.c:46
ChannelParams::kna
double kna
Definition: af_aexciter.c:29
AExciterContext::amount
double amount
Definition: af_aexciter.c:42
AExciterContext::level_in
double level_in
Definition: af_aexciter.c:40
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:33
a1
#define a1
Definition: regdef.h:47
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_aexciter.c:222
ceil
static __device__ float ceil(float a)
Definition: cuda_runtime.h:176
av_cold
#define av_cold
Definition: attributes.h:90
ChannelParams::lp
double lp[5]
Definition: af_aexciter.c:33
ChannelParams::rbdr
double rbdr
Definition: af_aexciter.c:29
s
#define s(width, name)
Definition: cbs_vp9.c:198
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:247
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
set_params
static void set_params(ChannelParams *p, double blend, double drive, double srate, double freq, double ceil)
Definition: af_aexciter.c:81
ChannelParams::hp
double hp[5]
Definition: af_aexciter.c:33
ctx
AVFormatContext * ctx
Definition: movenc.c:49
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:182
process_command
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
Definition: af_aexciter.c:246
if
if(ret)
Definition: filter_design.txt:179
ChannelParams::blend_old
double blend_old
Definition: af_aexciter.c:28
ff_af_aexciter
const AVFilter ff_af_aexciter
Definition: af_aexciter.c:268
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
fabs
static __device__ float fabs(float a)
Definition: cuda_runtime.h:182
avfilter_af_aexciter_inputs
static const AVFilterPad avfilter_af_aexciter_inputs[]
Definition: af_aexciter.c:259
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
AExciterContext::cp
ChannelParams * cp
Definition: af_aexciter.c:49
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
ChannelParams::drive_old
double drive_old
Definition: af_aexciter.c:28
c
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
AExciterContext::listen
int listen
Definition: af_aexciter.c:47
D
static double D(double x)
Definition: af_aexciter.c:74
OFFSET
#define OFFSET(x)
Definition: af_aexciter.c:52
ChannelParams::rdrive
double rdrive
Definition: af_aexciter.c:29
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:94
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:425
sample
#define sample
Definition: flacdsp_template.c:44
av_frame_is_writable
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:645
ChannelParams::lw
double lw[2][2]
Definition: af_aexciter.c:34
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:887
ChannelParams::kc
double kc
Definition: af_aexciter.c:30
ChannelParams::kpa
double kpa
Definition: af_aexciter.c:29
b2
static double b2(void *priv, double x, double y)
Definition: vf_xfade.c:2036
M
static double M(double x)
Definition: af_aexciter.c:69
a0
#define a0
Definition: regdef.h:46
M_PI
#define M_PI
Definition: mathematics.h:67
internal.h
ChannelParams::kpb
double kpb
Definition: af_aexciter.c:29
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_aexciter.c:229
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:454
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
ChannelParams::imr
double imr
Definition: af_aexciter.c:30
a2
#define a2
Definition: regdef.h:48
ChannelParams::ap
double ap
Definition: af_aexciter.c:29
ChannelParams
sample data coding information
Definition: mlp.h:97
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:39
ChannelParams::an
double an
Definition: af_aexciter.c:30
AExciterContext::blend
double blend
Definition: af_aexciter.c:44
av_calloc
void * av_calloc(size_t nmemb, size_t size)
Definition: mem.c:264
AVFilter
Filter definition.
Definition: avfilter.h:166
ret
ret
Definition: filter_design.txt:187
ChannelParams::sq
double sq
Definition: af_aexciter.c:30
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(aexciter)
ChannelParams::prev_out
double prev_out
Definition: af_aexciter.c:31
aexciter_options
static const AVOption aexciter_options[]
Definition: af_aexciter.c:55
avfilter.h
AExciterContext::level_out
double level_out
Definition: af_aexciter.c:41
AVFilterContext
An instance of a filter.
Definition: avfilter.h:407
ChannelParams::knb
double knb
Definition: af_aexciter.c:29
distortion_process
static double distortion_process(AExciterContext *s, ChannelParams *p, double in)
Definition: af_aexciter.c:145
mem.h
audio.h
AExciterContext::freq
double freq
Definition: af_aexciter.c:45
alpha
static const int16_t alpha[]
Definition: ilbcdata.h:55
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:261
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:183
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
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
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
b0
static double b0(void *priv, double x, double y)
Definition: vf_xfade.c:2034
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:61
bprocess
static double bprocess(double in, const double *const c, double *w1, double *w2)
Definition: af_aexciter.c:134