Go to the documentation of this file.
   84     for (
int i = 0; 
i < n / 2; 
i++)
 
   85         q[
i] = 1. / (-2. * cos(
M_PI * (2. * (
i + 1) + n - 1.) / (2. * n)));
 
   92     double w0 = 
s->cutoff / 
inlink->sample_rate;
 
   93     double K = tan(
M_PI * w0);
 
   96     s->bypass = w0 >= 0.5;
 
  100     if (!strcmp(
ctx->filter->name, 
"asubcut")) {
 
  101         s->filter_count = 
s->order / 2 + (
s->order & 1);
 
  107             double omega = 2. * tan(
M_PI * w0);
 
  109             coeffs->
b0 = 2. / (2. + omega);
 
  110             coeffs->
b1 = -coeffs->
b0;
 
  112             coeffs->
a1 = -(omega - 2.) / (2. + omega);
 
  116         for (
int b = (
s->order & 1); 
b < 
s->filter_count; 
b++) {
 
  118             const int idx = 
b - (
s->order & 1);
 
  119             double norm = 1.0 / (1.0 + K / q[idx] + K * K);
 
  122             coeffs->
b1 = -2.0 * coeffs->
b0;
 
  123             coeffs->
b2 = coeffs->
b0;
 
  124             coeffs->
a1 = -2.0 * (K * K - 1.0) * norm;
 
  125             coeffs->
a2 = -(1.0 - K / q[idx] + K * K) * norm;
 
  127     } 
else if (!strcmp(
ctx->filter->name, 
"asupercut")) {
 
  128         s->filter_count = 
s->order / 2 + (
s->order & 1);
 
  134             double omega = 2. * tan(
M_PI * w0);
 
  136             coeffs->
b0 = omega / (2. + omega);
 
  137             coeffs->
b1 = coeffs->
b0;
 
  139             coeffs->
a1 = -(omega - 2.) / (2. + omega);
 
  143         for (
int b = (
s->order & 1); 
b < 
s->filter_count; 
b++) {
 
  145             const int idx = 
b - (
s->order & 1);
 
  146             double norm = 1.0 / (1.0 + K / q[idx] + K * K);
 
  148             coeffs->
b0 = K * K * norm;
 
  149             coeffs->
b1 = 2.0 * coeffs->
b0;
 
  150             coeffs->
b2 = coeffs->
b0;
 
  151             coeffs->
a1 = -2.0 * (K * K - 1.0) * norm;
 
  152             coeffs->
a2 = -(1.0 - K / q[idx] + K * K) * norm;
 
  154     } 
else if (!strcmp(
ctx->filter->name, 
"asuperpass")) {
 
  155         double alpha, beta, gamma, theta;
 
  156         double theta_0 = 2. * 
M_PI * (
s->cutoff / 
inlink->sample_rate);
 
  159         s->filter_count = 
s->order / 2;
 
  160         d_E = (2. * tan(theta_0 / (2. * 
s->qfactor))) / sin(theta_0);
 
  162         for (
int b = 0; 
b < 
s->filter_count; 
b += 2) {
 
  163             double D = 2. * sin(((
b + 1) * 
M_PI) / (2. * 
s->filter_count));
 
  164             double A = (1. + pow((d_E / 2.), 2)) / (
D * d_E / 2.);
 
  165             double d = sqrt((d_E * 
D) / (
A + sqrt(
A * 
A - 1.)));
 
  166             double B = 
D * (d_E / 2.) / d;
 
  167             double W = 
B + sqrt(
B * 
B - 1.);
 
  169             for (
int j = 0; j < 2; j++) {
 
  173                     theta = 2. * atan(tan(theta_0 / 2.) / 
W);
 
  175                     theta = 2. * atan(
W * tan(theta_0 / 2.));
 
  177                 beta = 0.5 * ((1. - (d / 2.) * sin(theta)) / (1. + (d / 2.) * sin(theta)));
 
  178                 gamma = (0.5 + beta) * cos(theta);
 
  179                 alpha = 0.5 * (0.5 - beta) * sqrt(1. + pow((
W - (1. / 
W)) / d, 2.));
 
  181                 coeffs->
a1 =  2. * gamma;
 
  182                 coeffs->
a2 = -2. * beta;
 
  188     } 
else if (!strcmp(
ctx->filter->name, 
"asuperstop")) {
 
  189         double alpha, beta, gamma, theta;
 
  190         double theta_0 = 2. * 
M_PI * (
s->cutoff / 
inlink->sample_rate);
 
  193         s->filter_count = 
s->order / 2;
 
  194         d_E = (2. * tan(theta_0 / (2. * 
s->qfactor))) / sin(theta_0);
 
  196         for (
int b = 0; 
b < 
s->filter_count; 
b += 2) {
 
  197             double D = 2. * sin(((
b + 1) * 
M_PI) / (2. * 
s->filter_count));
 
  198             double A = (1. + pow((d_E / 2.), 2)) / (
D * d_E / 2.);
 
  199             double d = sqrt((d_E * 
D) / (
A + sqrt(
A * 
A - 1.)));
 
  200             double B = 
D * (d_E / 2.) / d;
 
  201             double W = 
B + sqrt(
B * 
B - 1.);
 
  203             for (
int j = 0; j < 2; j++) {
 
  207                     theta = 2. * atan(tan(theta_0 / 2.) / 
W);
 
  209                     theta = 2. * atan(
W * tan(theta_0 / 2.));
 
  211                 beta = 0.5 * ((1. - (d / 2.) * sin(theta)) / (1. + (d / 2.) * sin(theta)));
 
  212                 gamma = (0.5 + beta) * cos(theta);
 
  213                 alpha = 0.5 * (0.5 + beta) * ((1. - cos(theta)) / (1. - cos(theta_0)));
 
  215                 coeffs->
a1 =  2. * gamma;
 
  216                 coeffs->
a2 = -2. * beta;
 
  218                 coeffs->
b1 = -4. * 
alpha * cos(theta_0);
 
  231 #define FILTER(name, type)                                          \ 
  232 static int filter_channels_## name(AVFilterContext *ctx, void *arg, \ 
  233                                    int jobnr, int nb_jobs)          \ 
  235     ASuperCutContext *s = ctx->priv;                                \ 
  236     ThreadData *td = arg;                                           \ 
  237     AVFrame *out = td->out;                                         \ 
  238     AVFrame *in = td->in;                                           \ 
  239     const int start = (in->channels * jobnr) / nb_jobs;             \ 
  240     const int end = (in->channels * (jobnr+1)) / nb_jobs;           \ 
  241     const double level = s->level;                                  \ 
  243     for (int ch = start; ch < end; ch++) {                          \ 
  244         const type *src = (const type *)in->extended_data[ch];      \ 
  245         type *dst = (type *)out->extended_data[ch];                 \ 
  247         for (int b = 0; b < s->filter_count; b++) {                 \ 
  248             BiquadCoeffs *coeffs = &s->coeffs[b];                   \ 
  249             const type a1 = coeffs->a1;                             \ 
  250             const type a2 = coeffs->a2;                             \ 
  251             const type b0 = coeffs->b0;                             \ 
  252             const type b1 = coeffs->b1;                             \ 
  253             const type b2 = coeffs->b2;                             \ 
  254             type *w = ((type *)s->w->extended_data[ch]) + b * 2;    \ 
  256             for (int n = 0; n < in->nb_samples; n++) {              \ 
  257                 type sin = b ? dst[n] : src[n] * level;             \ 
  258                 type sout = sin * b0 + w[0];                        \ 
  260                 w[0] = b1 * sin + w[1] + a1 * sout;                 \ 
  261                 w[1] = b2 * sin + a2 * sout;                        \ 
  323                            char *res, 
int res_len, 
int flags)
 
  341 #define OFFSET(x) offsetof(ASuperCutContext, x) 
  342 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM 
  376     .priv_class      = &asupercut_class,
 
  399     .priv_class      = &asubcut_class,
 
  416 #define asuperpass_options asuperpass_asuperstop_options 
  420     .
name            = 
"asuperpass",
 
  424     .priv_class      = &asuperpass_class,
 
  433 #define asuperstop_options asuperpass_asuperstop_options 
  437     .
name            = 
"asuperstop",
 
  441     .priv_class      = &asuperstop_class,
 
  
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
 
static const AVOption asupercut_options[]
 
@ AV_SAMPLE_FMT_FLTP
float, planar
 
A list of supported channel layouts.
 
static int config_input(AVFilterLink *inlink)
 
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
 
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
 
static enum AVSampleFormat sample_fmts[]
 
enum MovChannelLayoutTag * layouts
 
AVFilter ff_af_asuperstop
 
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
 
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
 
This structure describes decoded (raw) audio or video data.
 
static void calc_q_factors(int n, double *q)
 
const char * name
Filter name.
 
AVFormatInternal * internal
An opaque field for libavformat internal usage.
 
A link between two filters.
 
static int query_formats(AVFilterContext *ctx)
 
AVFilter ff_af_asuperpass
 
#define FILTER(name, type)
 
static int get_coeffs(AVFilterContext *ctx)
 
A filter pad used for either input or output.
 
AVFILTER_DEFINE_CLASS(asupercut)
 
Describe the class of an AVClass context structure.
 
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
 
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
 
static const AVOption asubcut_options[]
 
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
 
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.
 
static av_cold void uninit(AVFilterContext *ctx)
 
int(* filter_channels)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
 
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
 
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
 
static const AVFilterPad inputs[]
 
int ff_filter_get_nb_threads(AVFilterContext *ctx)
Get number of threads for current filter instance.
 
AVSampleFormat
Audio sample formats.
 
Used for passing data between threads.
 
static const AVOption asuperpass_asuperstop_options[]
 
const char * name
Pad name.
 
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
 
@ AV_SAMPLE_FMT_DBLP
double, planar
 
#define AVFILTER_FLAG_SLICE_THREADS
The filter supports multithreading by splitting frames into multiple parts and processing them concur...
 
static const int16_t alpha[]
 
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 
#define flags(name, subs,...)
 
static const AVFilterPad outputs[]