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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-11-26 19:01:44 +02:00

lavfi/noise: switch to AVLFG noise generator

Signed-off-by: Paul B Mahol <onemda@gmail.com>
This commit is contained in:
Paul B Mahol 2013-02-17 21:05:33 +00:00
parent 259603b917
commit f4e29c408c

View File

@ -26,6 +26,7 @@
#include "libavutil/opt.h"
#include "libavutil/imgutils.h"
#include "libavutil/lfg.h"
#include "libavutil/parseutils.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
@ -47,6 +48,7 @@ typedef struct {
int strength;
unsigned flags;
int shiftptr;
AVLFG lfg;
int seed;
int8_t *noise;
int8_t *prev_shift[MAX_RES][3];
@ -91,11 +93,12 @@ AVFILTER_DEFINE_CLASS(noise);
static const int8_t patt[4] = { -1, 0, 1, 0 };
#define RAND_N(range) ((int) ((double) range * rand() / (RAND_MAX + 1.0)))
#define RAND_N(range) ((int) ((double) range * av_lfg_get(lfg) / (UINT_MAX + 1.0)))
static int init_noise(NoiseContext *n, int comp)
{
int8_t *noise = av_malloc(MAX_NOISE * sizeof(int8_t));
FilterParams *fp = &n->param[comp];
AVLFG *lfg = &n->param[comp].lfg;
int strength = fp->strength;
int flags = fp->flags;
int i, j;
@ -103,7 +106,7 @@ static int init_noise(NoiseContext *n, int comp)
if (!noise)
return AVERROR(ENOMEM);
srand(fp->seed);
av_lfg_init(&fp->lfg, fp->seed);
for (i = 0, j = 0; i < MAX_NOISE; i++, j++) {
if (flags & NOISE_UNIFORM) {
@ -125,8 +128,8 @@ static int init_noise(NoiseContext *n, int comp)
} else {
double x1, x2, w, y1;
do {
x1 = 2.0 * rand() / (float)RAND_MAX - 1.0;
x2 = 2.0 * rand() / (float)RAND_MAX - 1.0;
x1 = 2.0 * av_lfg_get(lfg) / (float)RAND_MAX - 1.0;
x2 = 2.0 * av_lfg_get(lfg) / (float)RAND_MAX - 1.0;
w = x1 * x1 + x2 * x2;
} while (w >= 1.0);
@ -148,11 +151,11 @@ static int init_noise(NoiseContext *n, int comp)
for (i = 0; i < MAX_RES; i++)
for (j = 0; j < 3; j++)
fp->prev_shift[i][j] = noise + (rand() & (MAX_SHIFT - 1));
fp->prev_shift[i][j] = noise + (av_lfg_get(lfg) & (MAX_SHIFT - 1));
if (!n->rand_shift_init) {
for (i = 0; i < MAX_RES; i++)
n->rand_shift[i] = rand() & (MAX_SHIFT - 1);
n->rand_shift[i] = av_lfg_get(lfg) & (MAX_SHIFT - 1);
n->rand_shift_init = 1;
}
@ -256,6 +259,7 @@ static void noise(uint8_t *dst, const uint8_t *src,
{
int8_t *noise = n->param[comp].noise;
int flags = n->param[comp].flags;
AVLFG *lfg = &n->param[comp].lfg;
int shift, y;
if (!noise) {
@ -272,7 +276,7 @@ static void noise(uint8_t *dst, const uint8_t *src,
for (y = 0; y < height; y++) {
if (flags & NOISE_TEMPORAL)
shift = rand() & (MAX_SHIFT - 1);
shift = av_lfg_get(lfg) & (MAX_SHIFT - 1);
else
shift = n->rand_shift[y];