[FFmpeg-devel] [PATCH 1/3] avfilter/avf_showspectrum: add posibility to display phase
Paul B Mahol
onemda at gmail.com
Mon Jan 11 00:21:51 CET 2016
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
doc/filters.texi | 3 +++
libavfilter/avf_showspectrum.c | 56 +++++++++++++++++++++++++++++++++++++++---
2 files changed, 55 insertions(+), 4 deletions(-)
diff --git a/doc/filters.texi b/doc/filters.texi
index efb050d..45d22f4 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -14712,6 +14712,9 @@ window function currently used.
@item gain
Set scale gain for calculating intensity color values.
Default value is @code{1}.
+
+ at item data
+Set which data to display. Can be @code{magnitude}, default or @code{phase}.
@end table
The usage is very similar to the showwaves filter; see the examples in that
diff --git a/libavfilter/avf_showspectrum.c b/libavfilter/avf_showspectrum.c
index 36cbdb2..7fd0ea9 100644
--- a/libavfilter/avf_showspectrum.c
+++ b/libavfilter/avf_showspectrum.c
@@ -42,6 +42,7 @@
#include "window_func.h"
enum DisplayMode { COMBINED, SEPARATE, NB_MODES };
+enum DataMode { D_MAGNITUDE, D_PHASE, NB_DMODES };
enum DisplayScale { LINEAR, SQRT, CBRT, LOG, FOURTHRT, FIFTHRT, NB_SCALES };
enum ColorMode { CHANNEL, INTENSITY, RAINBOW, MORELAND, NEBULAE, FIRE, FIERY, FRUIT, COOL, NB_CLMODES };
enum SlideMode { REPLACE, SCROLL, FULLFRAME, RSCROLL, NB_SLIDES };
@@ -60,12 +61,14 @@ typedef struct {
int color_mode; ///< display color scheme
int scale;
float saturation; ///< color saturation multiplier
+ int data;
int xpos; ///< x position (current column)
FFTContext *fft; ///< Fast Fourier Transform context
int fft_bits; ///< number of bits (FFT window size = 1<<fft_bits)
FFTComplex **fft_data; ///< bins holder for each (displayed) channels
float *window_func_lut; ///< Window function LUT
float **magnitudes;
+ float **phases;
int win_func;
int win_size;
double win_scale;
@@ -134,6 +137,9 @@ static const AVOption showspectrum_options[] = {
{ "horizontal", NULL, 0, AV_OPT_TYPE_CONST, {.i64=HORIZONTAL}, 0, 0, FLAGS, "orientation" },
{ "overlap", "set window overlap", OFFSET(overlap), AV_OPT_TYPE_FLOAT, {.dbl = 0}, 0, 1, FLAGS },
{ "gain", "set scale gain", OFFSET(gain), AV_OPT_TYPE_FLOAT, {.dbl = 1}, 0, 128, FLAGS },
+ { "data", "set data mode", OFFSET(data), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NB_DMODES-1, FLAGS, "data" },
+ { "magnitude", NULL, 0, AV_OPT_TYPE_CONST, {.i64=D_MAGNITUDE}, 0, 0, FLAGS, "data" },
+ { "phase", NULL, 0, AV_OPT_TYPE_CONST, {.i64=D_PHASE}, 0, 0, FLAGS, "data" },
{ NULL }
};
@@ -231,6 +237,11 @@ static av_cold void uninit(AVFilterContext *ctx)
av_freep(&s->magnitudes);
av_frame_free(&s->outpicref);
av_audio_fifo_free(s->fifo);
+ if (s->phases) {
+ for (i = 0; i < s->nb_display_channels; i++)
+ av_freep(&s->phases[i]);
+ }
+ av_freep(&s->phases);
}
static int query_formats(AVFilterContext *ctx)
@@ -329,6 +340,15 @@ static int config_output(AVFilterLink *outlink)
return AVERROR(ENOMEM);
}
+ s->phases = av_calloc(s->nb_display_channels, sizeof(*s->magnitudes));
+ if (!s->phases)
+ return AVERROR(ENOMEM);
+ for (i = 0; i < s->nb_display_channels; i++) {
+ s->phases[i] = av_calloc(s->orientation == VERTICAL ? s->h : s->w, sizeof(**s->phases));
+ if (!s->phases[i])
+ return AVERROR(ENOMEM);
+ }
+
s->fft_data = av_calloc(s->nb_display_channels, sizeof(*s->fft_data));
if (!s->fft_data)
return AVERROR(ENOMEM);
@@ -427,6 +447,7 @@ static void run_fft(ShowSpectrumContext *s, AVFrame *fin)
#define RE(y, ch) s->fft_data[ch][y].re
#define IM(y, ch) s->fft_data[ch][y].im
#define MAGNITUDE(y, ch) hypot(RE(y, ch), IM(y, ch))
+#define PHASE(y, ch) atan2(IM(y, ch), RE(y, ch))
static void calc_magnitudes(ShowSpectrumContext *s)
{
@@ -440,6 +461,18 @@ static void calc_magnitudes(ShowSpectrumContext *s)
}
}
+static void calc_phases(ShowSpectrumContext *s)
+{
+ int ch, y, h = s->orientation == VERTICAL ? s->h : s->w;
+
+ for (ch = 0; ch < s->nb_display_channels; ch++) {
+ float *phases = s->phases[ch];
+
+ for (y = 0; y < h; y++)
+ phases[y] = (PHASE(y, ch) / M_PI + 1) / 2;
+ }
+}
+
static void acalc_magnitudes(ShowSpectrumContext *s)
{
int ch, y, h = s->orientation == VERTICAL ? s->h : s->w;
@@ -578,7 +611,7 @@ static int plot_spectrum_column(AVFilterLink *inlink, AVFrame *insamples)
AVFilterLink *outlink = ctx->outputs[0];
ShowSpectrumContext *s = ctx->priv;
AVFrame *outpicref = s->outpicref;
- const double w = s->win_scale;
+ const double w = s->data == D_PHASE ? 1 : s->win_scale;
const float g = s->gain;
int h = s->orientation == VERTICAL ? s->channel_height : s->channel_width;
@@ -590,6 +623,7 @@ static int plot_spectrum_column(AVFilterLink *inlink, AVFrame *insamples)
for (ch = 0; ch < s->nb_display_channels; ch++) {
float *magnitudes = s->magnitudes[ch];
+ float *phases = s->phases[ch];
float yf, uf, vf;
/* decide color range */
@@ -599,9 +633,20 @@ static int plot_spectrum_column(AVFilterLink *inlink, AVFrame *insamples)
for (y = 0; y < h; y++) {
int row = (s->mode == COMBINED) ? y : ch * h + y;
float *out = &s->combine_buffer[3 * row];
+ float a;
- /* get magnitude */
- float a = g * w * magnitudes[y];
+ switch (s->data) {
+ case D_MAGNITUDE:
+ /* get magnitude */
+ a = g * w * magnitudes[y];
+ break;
+ case D_PHASE:
+ /* get phase */
+ a = phases[y];
+ break;
+ default:
+ av_assert0(0);
+ }
/* apply scale */
switch (s->scale) {
@@ -766,7 +811,10 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
av_assert0(fin->nb_samples == s->win_size);
run_fft(s, fin);
- calc_magnitudes(s);
+ if (s->data == D_MAGNITUDE)
+ calc_magnitudes(s);
+ if (s->data == D_PHASE)
+ calc_phases(s);
ret = plot_spectrum_column(inlink, fin);
av_frame_free(&fin);
--
1.9.1
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