lavfi/af_sofalizer: remove exp2 and replace clz by ff_clz

ff_clz is faster, and uses an intrinsic (at the moment on GCC). exp2 is
a wasteful function for a simple integer exponentiation.

Untested.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This commit is contained in:
Ganesh Ajjanagadde 2015-12-29 13:16:08 -08:00
parent 77eeaa2c3d
commit 9dba3f8f09

View File

@ -30,6 +30,7 @@
#include "libavcodec/avfft.h"
#include "libavutil/float_dsp.h"
#include "libavutil/intmath.h"
#include "libavutil/opt.h"
#include "avfilter.h"
#include "internal.h"
@ -952,18 +953,6 @@ static av_cold int init(AVFilterContext *ctx)
return 0;
}
static inline unsigned clz(unsigned x)
{
unsigned i = sizeof(x) * 8;
while (x) {
x >>= 1;
i--;
}
return i;
}
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
@ -996,8 +985,8 @@ static int config_input(AVFilterLink *inlink)
}
/* buffer length is longest IR plus max. delay -> next power of 2
(32 - count leading zeros gives required exponent) */
s->buffer_length = exp2(32 - clz((uint32_t)n_max));
s->n_fft = exp2(32 - clz((uint32_t)(n_max + inlink->sample_rate)));
s->buffer_length = 1 << (32 - ff_clz(n_max));
s->n_fft = 1 << (32 - ff_clz(n_max + inlink->sample_rate));
if (s->type == FREQUENCY_DOMAIN) {
av_fft_end(s->fft[0]);