[FFmpeg-cvslog] avfilter/showcqt: add and extend tlength and volume options
Muhammad Faiz
git at videolan.org
Fri Aug 8 18:59:52 CEST 2014
ffmpeg | branch: master | Muhammad Faiz <mfcc64 at gmail.com> | Fri Aug 8 21:58:35 2014 +0700| [94494dab910133106e80ece0f79935d78138e415] | committer: Michael Niedermayer
avfilter/showcqt: add and extend tlength and volume options
Add a tlength option with frequency and timeclamp variable
Add to the volume option support for frequency and timeclamp variable,
a_weighting, b_weighting and c_weighting functions
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=94494dab910133106e80ece0f79935d78138e415
---
doc/filters.texi | 42 ++++++++++++++++++++--
libavfilter/avf_showcqt.c | 87 ++++++++++++++++++++++++++++++++++++++++-----
2 files changed, 119 insertions(+), 10 deletions(-)
diff --git a/doc/filters.texi b/doc/filters.texi
index f59926a..e0759fc 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -10515,8 +10515,34 @@ The filter accepts the following options:
@table @option
@item volume
-Specify the transform volume (multiplier). Acceptable value is [1.0, 100.0].
-Default value is @code{16.0}.
+Specify transform volume (multiplier) expression. The expression can contain
+variables:
+ at table @option
+ at item frequency, freq, f
+the frequency where transform is evaluated
+ at item timeclamp, tc
+value of timeclamp option
+ at end table
+and functions:
+ at table @option
+ at item a_weighting(f)
+A-weighting of equal loudness
+ at item b_weighting(f)
+B-weighting of equal loudness
+ at item c_weighting(f)
+C-weighting of equal loudness
+ at end table
+Default value is @code{16}.
+
+ at item tlength
+Specify transform length expression. The expression can contain variables:
+ at table @option
+ at item frequency, freq, f
+the frequency where transform is evaluated
+ at item timeclamp, tc
+value of timeclamp option
+ at end table
+Default value is @code{384/f*tc/(384/f+tc)}.
@item timeclamp
Specify the transform timeclamp. At low frequency, there is trade-off between
@@ -10587,6 +10613,18 @@ ffplay -f lavfi 'aevalsrc=0.1*sin(2*PI*55*t)+0.1*sin(4*PI*55*t)+0.1*sin(6*PI*55*
asplit[a][out1]; [a] showcqt=timeclamp=0.5 [out0]'
@end example
+ at item
+B-weighting of equal loudness
+ at example
+volume=16*b_weighting(f)
+ at end example
+
+ at item
+Lower Q factor
+ at example
+tlength=100/f*tc/(100/f+tc)
+ at end example
+
@end itemize
@section showspectrum
diff --git a/libavfilter/avf_showcqt.c b/libavfilter/avf_showcqt.c
index 60e8129..012362b 100644
--- a/libavfilter/avf_showcqt.c
+++ b/libavfilter/avf_showcqt.c
@@ -26,6 +26,7 @@
#include "libavutil/xga_font_data.h"
#include "libavutil/qsort.h"
#include "libavutil/time.h"
+#include "libavutil/eval.h"
#include "avfilter.h"
#include "internal.h"
@@ -49,6 +50,10 @@
#define SPECTOGRAM_START (VIDEO_HEIGHT-SPECTOGRAM_HEIGHT)
#define BASE_FREQ 20.051392800492
#define COEFF_CLAMP 1.0e-4
+#define TLENGTH_MIN 0.001
+#define TLENGTH_DEFAULT "384/f*tc/(384/f+tc)"
+#define VOLUME_MIN 1e-10
+#define VOLUME_MAX 100.0
typedef struct {
FFTSample value;
@@ -75,7 +80,8 @@ typedef struct {
int fft_bits;
int req_fullfilled;
int remaining_fill;
- double volume;
+ char *tlength;
+ char *volume;
double timeclamp; /* lower timeclamp, time-accurate, higher timeclamp, freq-accurate (at low freq)*/
float coeffclamp; /* lower coeffclamp, more precise, higher coeffclamp, faster */
int fullhd; /* if true, output video is at full HD resolution, otherwise it will be halved */
@@ -88,7 +94,8 @@ typedef struct {
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption showcqt_options[] = {
- { "volume", "set volume", OFFSET(volume), AV_OPT_TYPE_DOUBLE, { .dbl = 16 }, 0.1, 100, FLAGS },
+ { "volume", "set volume", OFFSET(volume), AV_OPT_TYPE_STRING, { .str = "16" }, CHAR_MIN, CHAR_MAX, FLAGS },
+ { "tlength", "set transform length", OFFSET(tlength), AV_OPT_TYPE_STRING, { .str = TLENGTH_DEFAULT }, CHAR_MIN, CHAR_MAX, FLAGS },
{ "timeclamp", "set timeclamp", OFFSET(timeclamp), AV_OPT_TYPE_DOUBLE, { .dbl = 0.17 }, 0.1, 1.0, FLAGS },
{ "coeffclamp", "set coeffclamp", OFFSET(coeffclamp), AV_OPT_TYPE_FLOAT, { .dbl = 1 }, 0.1, 10, FLAGS },
{ "gamma", "set gamma", OFFSET(gamma), AV_OPT_TYPE_FLOAT, { .dbl = 3 }, 1, 7, FLAGS },
@@ -246,6 +253,28 @@ static void load_freetype_font(AVFilterContext *ctx)
}
#endif
+static double a_weighting(void *p, double f)
+{
+ double ret = 12200.0*12200.0 * (f*f*f*f);
+ ret /= (f*f + 20.6*20.6) * (f*f + 12200.0*12200.0) *
+ sqrt((f*f + 107.7*107.7) * (f*f + 737.9*737.9));
+ return ret;
+}
+
+static double b_weighting(void *p, double f)
+{
+ double ret = 12200.0*12200.0 * (f*f*f);
+ ret /= (f*f + 20.6*20.6) * (f*f + 12200.0*12200.0) * sqrt(f*f + 158.5*158.5);
+ return ret;
+}
+
+static double c_weighting(void *p, double f)
+{
+ double ret = 12200.0*12200.0 * (f*f);
+ ret /= (f*f + 20.6*20.6) * (f*f + 12200.0*12200.0);
+ return ret;
+}
+
static inline int qsort_sparsecoeff(const SparseCoeff *a, const SparseCoeff *b)
{
if (fabsf(a->value) >= fabsf(b->value))
@@ -259,7 +288,11 @@ static int config_output(AVFilterLink *outlink)
AVFilterContext *ctx = outlink->src;
AVFilterLink *inlink = ctx->inputs[0];
ShowCQTContext *s = ctx->priv;
- int fft_len, k, x, y;
+ AVExpr *tlength_expr, *volume_expr;
+ static const char * const expr_vars[] = { "timeclamp", "tc", "frequency", "freq", "f", NULL };
+ static const char * const expr_func_names[] = { "a_weighting", "b_weighting", "c_weighting", NULL };
+ static double (* const expr_funcs[])(void *, double) = { a_weighting, b_weighting, c_weighting, NULL };
+ int fft_len, k, x, y, ret;
int num_coeffs = 0;
int rate = inlink->sample_rate;
double max_len = rate * (double) s->timeclamp;
@@ -307,12 +340,22 @@ static int config_output(AVFilterLink *outlink)
av_log(ctx, AV_LOG_INFO, "Calculating spectral kernel, please wait\n");
start_time = av_gettime_relative();
+ ret = av_expr_parse(&tlength_expr, s->tlength, expr_vars, NULL, NULL, NULL, NULL, 0, ctx);
+ if (ret < 0)
+ return ret;
+ ret = av_expr_parse(&volume_expr, s->volume, expr_vars, expr_func_names,
+ expr_funcs, NULL, NULL, 0, ctx);
+ if (ret < 0) {
+ av_expr_free(tlength_expr);
+ return ret;
+ }
for (k = 0; k < VIDEO_WIDTH; k++) {
int hlen = fft_len >> 1;
float total = 0;
float partial = 0;
double freq = BASE_FREQ * exp2(k * (1.0/192.0));
- double tlen = rate * (24.0 * 16.0) /freq;
+ double tlen, tlength, volume;
+ double expr_vars_val[] = { s->timeclamp, s->timeclamp, freq, freq, freq, 0 };
/* a window function from Albert H. Nuttall,
* "Some Windows with Very Good Sidelobe Behavior"
* -93.32 dB peak sidelobe and 18 dB/octave asymptotic decay
@@ -324,10 +367,33 @@ static int config_output(AVFilterLink *outlink)
double sv_step, cv_step, sv, cv;
double sw_step, cw_step, sw, cw, w;
- tlen = tlen * max_len / (tlen + max_len);
+ tlength = av_expr_eval(tlength_expr, expr_vars_val, NULL);
+ if (isnan(tlength)) {
+ av_log(ctx, AV_LOG_WARNING, "at freq %g: tlength is nan, setting it to %g\n", freq, s->timeclamp);
+ tlength = s->timeclamp;
+ } else if (tlength < TLENGTH_MIN) {
+ av_log(ctx, AV_LOG_WARNING, "at freq %g: tlength is %g, setting it to %g\n", freq, tlength, TLENGTH_MIN);
+ tlength = TLENGTH_MIN;
+ } else if (tlength > s->timeclamp) {
+ av_log(ctx, AV_LOG_WARNING, "at freq %g: tlength is %g, setting it to %g\n", freq, tlength, s->timeclamp);
+ tlength = s->timeclamp;
+ }
+
+ volume = FFABS(av_expr_eval(volume_expr, expr_vars_val, NULL));
+ if (isnan(volume)) {
+ av_log(ctx, AV_LOG_WARNING, "at freq %g: volume is nan, setting it to 0\n", freq);
+ volume = VOLUME_MIN;
+ } else if (volume < VOLUME_MIN) {
+ volume = VOLUME_MIN;
+ } else if (volume > VOLUME_MAX) {
+ av_log(ctx, AV_LOG_WARNING, "at freq %g: volume is %g, setting it to %g\n", freq, volume, VOLUME_MAX);
+ volume = VOLUME_MAX;
+ }
+
+ tlen = tlength * rate;
s->fft_data[0].re = 0;
s->fft_data[0].im = 0;
- s->fft_data[hlen].re = (1.0 + a1 + a2 + a3) * (1.0/tlen) * s->volume * (1.0/fft_len);
+ s->fft_data[hlen].re = (1.0 + a1 + a2 + a3) * (1.0/tlen) * volume * (1.0/fft_len);
s->fft_data[hlen].im = 0;
sv_step = sv = sin(2.0*M_PI*freq*(1.0/rate));
cv_step = cv = cos(2.0*M_PI*freq*(1.0/rate));
@@ -341,7 +407,7 @@ static int config_output(AVFilterLink *outlink)
cw2 = cw * cw - sw * sw;
sw2 = cw * sw + sw * cw;
cw3 = cw * cw2 - sw * sw2;
- w = (1.0 + a1 * cw + a2 * cw2 + a3 * cw3) * (1.0/tlen) * s->volume * (1.0/fft_len);
+ w = (1.0 + a1 * cw + a2 * cw2 + a3 * cw3) * (1.0/tlen) * volume * (1.0/fft_len);
s->fft_data[hlen + x].re = w * cv;
s->fft_data[hlen + x].im = w * sv;
s->fft_data[hlen - x].re = s->fft_data[hlen + x].re;
@@ -378,14 +444,19 @@ static int config_output(AVFilterLink *outlink)
s->coeffs_len[k] = fft_len - x;
num_coeffs += s->coeffs_len[k];
s->coeffs[k] = av_malloc_array(s->coeffs_len[k], sizeof(*s->coeffs[k]));
- if (!s->coeffs[k])
+ if (!s->coeffs[k]) {
+ av_expr_free(volume_expr);
+ av_expr_free(tlength_expr);
return AVERROR(ENOMEM);
+ }
for (y = 0; y < s->coeffs_len[k]; y++)
s->coeffs[k][y] = s->coeff_sort[x+y];
break;
}
}
}
+ av_expr_free(volume_expr);
+ av_expr_free(tlength_expr);
end_time = av_gettime_relative();
av_log(ctx, AV_LOG_INFO, "Elapsed time %.6f s (fft_len=%u, num_coeffs=%u)\n", 1e-6 * (end_time-start_time), fft_len, num_coeffs);
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