[FFmpeg-cvslog] avfilter/avf_showspectrum: store win_size in private context and calculate it only once
Paul B Mahol
git at videolan.org
Sat Jan 2 18:53:45 CET 2016
ffmpeg | branch: master | Paul B Mahol <onemda at gmail.com> | Thu Dec 31 20:31:32 2015 +0100| [7f7a9dd78227343bd8ca05610bd3f913d62a2db4] | committer: Paul B Mahol
avfilter/avf_showspectrum: store win_size in private context and calculate it only once
Signed-off-by: Paul B Mahol <onemda at gmail.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7f7a9dd78227343bd8ca05610bd3f913d62a2db4
---
libavfilter/avf_showspectrum.c | 39 +++++++++++++++++----------------------
1 file changed, 17 insertions(+), 22 deletions(-)
diff --git a/libavfilter/avf_showspectrum.c b/libavfilter/avf_showspectrum.c
index 5380994..0fa1be1 100644
--- a/libavfilter/avf_showspectrum.c
+++ b/libavfilter/avf_showspectrum.c
@@ -64,6 +64,7 @@ typedef struct {
FFTSample **rdft_data; ///< bins holder for each (displayed) channels
float *window_func_lut; ///< Window function LUT
int win_func;
+ int win_size;
double win_scale;
float overlap;
int skip_samples;
@@ -225,7 +226,7 @@ static int config_output(AVFilterLink *outlink)
AVFilterContext *ctx = outlink->src;
AVFilterLink *inlink = ctx->inputs[0];
ShowSpectrumContext *s = ctx->priv;
- int i, rdft_bits, win_size, h, w;
+ int i, rdft_bits, h, w;
float overlap;
outlink->w = s->w;
@@ -243,7 +244,7 @@ static int config_output(AVFilterLink *outlink)
/* RDFT window size (precision) according to the requested output frame width */
for (rdft_bits = 1; 1 << rdft_bits < 2 * w; rdft_bits++);
}
- win_size = 1 << rdft_bits;
+ s->win_size = 1 << rdft_bits;
/* (re-)configuration if the video output changed (or first init) */
if (rdft_bits != s->rdft_bits) {
@@ -270,27 +271,27 @@ static int config_output(AVFilterLink *outlink)
if (!s->rdft_data)
return AVERROR(ENOMEM);
for (i = 0; i < s->nb_display_channels; i++) {
- s->rdft_data[i] = av_calloc(win_size, sizeof(**s->rdft_data));
+ s->rdft_data[i] = av_calloc(s->win_size, sizeof(**s->rdft_data));
if (!s->rdft_data[i])
return AVERROR(ENOMEM);
}
/* pre-calc windowing function */
s->window_func_lut =
- av_realloc_f(s->window_func_lut, win_size,
+ av_realloc_f(s->window_func_lut, s->win_size,
sizeof(*s->window_func_lut));
if (!s->window_func_lut)
return AVERROR(ENOMEM);
- ff_generate_window_func(s->window_func_lut, win_size, s->win_func, &overlap);
+ ff_generate_window_func(s->window_func_lut, s->win_size, s->win_func, &overlap);
if (s->overlap == 1)
s->overlap = overlap;
- s->skip_samples = (1. - s->overlap) * win_size;
+ s->skip_samples = (1. - s->overlap) * s->win_size;
if (s->skip_samples < 1) {
av_log(ctx, AV_LOG_ERROR, "overlap %f too big\n", s->overlap);
return AVERROR(EINVAL);
}
- for (s->win_scale = 0, i = 0; i < win_size; i++) {
+ for (s->win_scale = 0, i = 0; i < s->win_size; i++) {
s->win_scale += s->window_func_lut[i] * s->window_func_lut[i];
}
s->win_scale = 1. / (sqrt(s->win_scale) * 32768.);
@@ -313,7 +314,7 @@ static int config_output(AVFilterLink *outlink)
(s->orientation == HORIZONTAL && s->xpos >= outlink->h))
s->xpos = 0;
- outlink->frame_rate = av_make_q(inlink->sample_rate, win_size * (1.-s->overlap));
+ outlink->frame_rate = av_make_q(inlink->sample_rate, s->win_size * (1.-s->overlap));
if (s->orientation == VERTICAL && s->sliding == FULLFRAME)
outlink->frame_rate.den *= outlink->w;
if (s->orientation == HORIZONTAL && s->sliding == FULLFRAME)
@@ -330,10 +331,10 @@ static int config_output(AVFilterLink *outlink)
}
av_log(ctx, AV_LOG_VERBOSE, "s:%dx%d RDFT window size:%d\n",
- s->w, s->h, win_size);
+ s->w, s->h, s->win_size);
av_audio_fifo_free(s->fifo);
- s->fifo = av_audio_fifo_alloc(inlink->format, inlink->channels, win_size);
+ s->fifo = av_audio_fifo_alloc(inlink->format, inlink->channels, s->win_size);
if (!s->fifo)
return AVERROR(ENOMEM);
return 0;
@@ -376,23 +377,18 @@ static int plot_spectrum_column(AVFilterLink *inlink, AVFrame *insamples)
AVFilterLink *outlink = ctx->outputs[0];
ShowSpectrumContext *s = ctx->priv;
AVFrame *outpicref = s->outpicref;
-
- /* nb_freq contains the power of two superior or equal to the output image
- * height (or half the RDFT window size) */
- const int nb_freq = 1 << (s->rdft_bits - 1);
- const int win_size = nb_freq << 1;
const double w = s->win_scale;
int h = s->orientation == VERTICAL ? s->channel_height : s->channel_width;
int ch, plane, n, x, y;
- av_assert0(insamples->nb_samples == win_size);
+ av_assert0(insamples->nb_samples == s->win_size);
/* fill RDFT input with the number of samples available */
for (ch = 0; ch < s->nb_display_channels; ch++) {
const int16_t *p = (int16_t *)insamples->extended_data[ch];
- for (n = 0; n < win_size; n++)
+ for (n = 0; n < s->win_size; n++)
s->rdft_data[ch][n] = p[n] * s->window_func_lut[n];
}
@@ -610,21 +606,20 @@ static int plot_spectrum_column(AVFilterLink *inlink, AVFrame *insamples)
return ret;
}
- return win_size;
+ return s->win_size;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
{
AVFilterContext *ctx = inlink->dst;
ShowSpectrumContext *s = ctx->priv;
- unsigned win_size = 1 << s->rdft_bits;
AVFrame *fin = NULL;
int ret = 0;
av_audio_fifo_write(s->fifo, (void **)insamples->extended_data, insamples->nb_samples);
av_frame_free(&insamples);
- while (av_audio_fifo_size(s->fifo) >= win_size) {
- fin = ff_get_audio_buffer(inlink, win_size);
+ while (av_audio_fifo_size(s->fifo) >= s->win_size) {
+ fin = ff_get_audio_buffer(inlink, s->win_size);
if (!fin) {
ret = AVERROR(ENOMEM);
goto fail;
@@ -632,7 +627,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
fin->pts = s->pts;
s->pts += s->skip_samples;
- ret = av_audio_fifo_peek(s->fifo, (void **)fin->extended_data, win_size);
+ ret = av_audio_fifo_peek(s->fifo, (void **)fin->extended_data, s->win_size);
if (ret < 0)
goto fail;
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