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remove arch-dependent rand()

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let's use our own simple pseudo-random number generator

Change-Id: I7b4a190cdf4d338b1fae5ef3622ebd82c6e19274
This commit is contained in:
Pascal Massimino 2012-05-22 00:13:01 -07:00
parent d40e7653db
commit ec122e0986
1 changed files with 14 additions and 5 deletions
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19
src/enc/histogram.c
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@ -261,11 +261,19 @@ static void HistogramBuildImage(int xsize, int histo_bits,
} }
} }
static uint32_t MyRand(uint32_t *seed) {
*seed *= 16807U;
if (*seed == 0) {
*seed = 1;
}
return *seed;
}
static int HistogramCombine(const VP8LHistogramSet* const in, static int HistogramCombine(const VP8LHistogramSet* const in,
VP8LHistogramSet* const out, int num_pairs) { VP8LHistogramSet* const out, int num_pairs) {
int ok = 0; int ok = 0;
int i, iter; int i, iter;
unsigned int seed = 0; uint32_t seed = 0;
int tries_with_no_success = 0; int tries_with_no_success = 0;
const int min_cluster_size = 2; const int min_cluster_size = 2;
int out_size = in->size; int out_size = in->size;
@ -288,13 +296,14 @@ static int HistogramCombine(const VP8LHistogramSet* const in,
double best_cost_diff = 0.; double best_cost_diff = 0.;
int best_idx1 = 0, best_idx2 = 1; int best_idx1 = 0, best_idx2 = 1;
int j; int j;
seed += iter;
for (j = 0; j < num_pairs; ++j) { for (j = 0; j < num_pairs; ++j) {
double curr_cost_diff; double curr_cost_diff;
// Choose two histograms at random and try to combine them. // Choose two histograms at random and try to combine them.
const int idx1 = rand_r(&seed) % out_size; const uint32_t idx1 = MyRand(&seed) % out_size;
const int tmp = ((j & 7) + 1) % (out_size - 1); const uint32_t tmp = ((j & 7) + 1) % (out_size - 1);
const int diff = (tmp < 3) ? tmp : rand_r(&seed) % (out_size - 1); const uint32_t diff = (tmp < 3) ? tmp : MyRand(&seed) % (out_size - 1);
const int idx2 = (idx1 + diff + 1) % out_size; const uint32_t idx2 = (idx1 + diff + 1) % out_size;
if (idx1 == idx2) { if (idx1 == idx2) {
continue; continue;
} }