avfilter/avf_showspectrum: make some helper functions

Signed-off-by: Paul B Mahol <onemda@gmail.com>
This commit is contained in:
Paul B Mahol 2016-01-02 15:25:58 +01:00
parent d35c029cbf
commit 2b172cb625

View File

@ -428,6 +428,61 @@ static void scale_magnitudes(ShowSpectrumContext *s, float scale)
}
}
static void pick_color(ShowSpectrumContext *s,
float yf, float uf, float vf,
float a, float *out)
{
if (s->color_mode > CHANNEL) {
const int cm = s->color_mode;
float y, u, v;
int i;
for (i = 1; i < FF_ARRAY_ELEMS(color_table[cm]) - 1; i++)
if (color_table[cm][i].a >= a)
break;
// i now is the first item >= the color
// now we know to interpolate between item i - 1 and i
if (a <= color_table[cm][i - 1].a) {
y = color_table[cm][i - 1].y;
u = color_table[cm][i - 1].u;
v = color_table[cm][i - 1].v;
} else if (a >= color_table[cm][i].a) {
y = color_table[cm][i].y;
u = color_table[cm][i].u;
v = color_table[cm][i].v;
} else {
float start = color_table[cm][i - 1].a;
float end = color_table[cm][i].a;
float lerpfrac = (a - start) / (end - start);
y = color_table[cm][i - 1].y * (1.0f - lerpfrac)
+ color_table[cm][i].y * lerpfrac;
u = color_table[cm][i - 1].u * (1.0f - lerpfrac)
+ color_table[cm][i].u * lerpfrac;
v = color_table[cm][i - 1].v * (1.0f - lerpfrac)
+ color_table[cm][i].v * lerpfrac;
}
out[0] += y * yf;
out[1] += u * uf;
out[2] += v * vf;
} else {
out[0] += a * yf;
out[1] += a * uf;
out[2] += a * vf;
}
}
static void clear_combine_buffer(ShowSpectrumContext *s, int size)
{
int y;
for (y = 0; y < size; y++) {
s->combine_buffer[3 * y ] = 0;
s->combine_buffer[3 * y + 1] = 127.5;
s->combine_buffer[3 * y + 2] = 127.5;
}
}
static int plot_spectrum_column(AVFilterLink *inlink, AVFrame *insamples)
{
int ret;
@ -442,19 +497,7 @@ static int plot_spectrum_column(AVFilterLink *inlink, AVFrame *insamples)
/* fill a new spectrum column */
/* initialize buffer for combining to black */
if (s->orientation == VERTICAL) {
for (y = 0; y < outlink->h; y++) {
s->combine_buffer[3 * y ] = 0;
s->combine_buffer[3 * y + 1] = 127.5;
s->combine_buffer[3 * y + 2] = 127.5;
}
} else {
for (y = 0; y < outlink->w; y++) {
s->combine_buffer[3 * y ] = 0;
s->combine_buffer[3 * y + 1] = 127.5;
s->combine_buffer[3 * y + 2] = 127.5;
}
}
clear_combine_buffer(s, s->orientation == VERTICAL ? outlink->h : outlink->w);
for (ch = 0; ch < s->nb_display_channels; ch++) {
float *magnitudes = s->magnitudes[ch];
@ -532,44 +575,7 @@ static int plot_spectrum_column(AVFilterLink *inlink, AVFrame *insamples)
av_assert0(0);
}
if (s->color_mode > CHANNEL) {
const int cm = s->color_mode;
float y, u, v;
int i;
for (i = 1; i < FF_ARRAY_ELEMS(color_table[cm]) - 1; i++)
if (color_table[cm][i].a >= a)
break;
// i now is the first item >= the color
// now we know to interpolate between item i - 1 and i
if (a <= color_table[cm][i - 1].a) {
y = color_table[cm][i - 1].y;
u = color_table[cm][i - 1].u;
v = color_table[cm][i - 1].v;
} else if (a >= color_table[cm][i].a) {
y = color_table[cm][i].y;
u = color_table[cm][i].u;
v = color_table[cm][i].v;
} else {
float start = color_table[cm][i - 1].a;
float end = color_table[cm][i].a;
float lerpfrac = (a - start) / (end - start);
y = color_table[cm][i - 1].y * (1.0f - lerpfrac)
+ color_table[cm][i].y * lerpfrac;
u = color_table[cm][i - 1].u * (1.0f - lerpfrac)
+ color_table[cm][i].u * lerpfrac;
v = color_table[cm][i - 1].v * (1.0f - lerpfrac)
+ color_table[cm][i].v * lerpfrac;
}
out[0] += y * yf;
out[1] += u * uf;
out[2] += v * vf;
} else {
out[0] += a * yf;
out[1] += a * uf;
out[2] += a * vf;
}
pick_color(s, yf, uf, vf, a, out);
}
}