generic-library/vpx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Merge changes I11786887,Ia91823ad

Browse Source 
* changes:
  vpx_dsp/get_prob: relocate den == 0 test
  vpx_dsp/get_prob: make clip_prob branchless
This commit is contained in:
James Zern 2016-09-29 19:11:35 +00:00 committed by Gerrit Code Review
commit 691ef20272
1 changed files with 12 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
vpx_dsp/prob.h
View File

@ -11,6 +11,8 @@
#ifndef VPX_DSP_PROB_H_
#define VPX_DSP_PROB_H_
#include <assert.h>
#include "./vpx_config.h"
#include "./vpx_dsp_common.h"
@ -43,17 +45,20 @@ typedef int8_t vpx_tree_index;
typedef const vpx_tree_index vpx_tree[];
static INLINE vpx_prob clip_prob(int p) {
return (p > 255) ? 255 : (p < 1) ? 1 : p;
}
static INLINE vpx_prob get_prob(unsigned int num, unsigned int den) {
if (den == 0) return 128u;
return clip_prob((int)(((int64_t)num * 256 + (den >> 1)) / den));
assert(den != 0);
{
const int p = (int)(((int64_t)num * 256 + (den >> 1)) / den);
// (p > 255) ? 255 : (p < 1) ? 1 : p;
const int clipped_prob = p | ((255 - p) >> 23) | (p == 0);
return (vpx_prob)clipped_prob;
}
}
static INLINE vpx_prob get_binary_prob(unsigned int n0, unsigned int n1) {
return get_prob(n0, n0 + n1);
const unsigned int den = n0 + n1;
if (den == 0) return 128u;
return get_prob(n0, den);
}
/* This function assumes prob1 and prob2 are already within [1,255] range. */