3DLut电影级调色算法附完整C代码-USB迷|专注于互联网分享

2024年4月6日发(作者：衣晓灵)

/* ref:/serge-rgb/TinyJPEG/blob/master/tiny_jpeg.h */

#include

#include "timing.h"

#include

#ifndef _MAX_DRIVE

#define _MAX_DRIVE 3

#endif

#ifndef _MAX_FNAME

#define _MAX_FNAME 256

#endif

#ifndef _MAX_EXT

#define _MAX_EXT 256

#endif

#ifndef _MAX_DIR

#define _MAX_DIR 256

#endif

#ifdef _MSC_VER

#endif

#ifndef MIN

#define MIN(a, b) ( (a) > (b) ? (b) : (a) )

#endif

#ifndef _NEAR

#define _NEAR(x) ( (int) ( (x) + .5) )

#endif

#ifndef PREV

#define PREV(x) ( (int) (x) )

#endif

#ifndef NEXT

#define NEXT(x) (MIN( (int) (x) + 1, lut3d->lutsize - 1 ) )

#endif

#ifndef R

#define R 0

#endif

#ifndef G

#define G 1

#endif

#ifndef B

#define B 2

#endif

#ifndef A

#define A 3

#endif

#ifndef MAX_LEVEL

#define MAX_LEVEL 64

#endif

enum interp_mode {

INTERPOLATE_NEAREST,

INTERPOLATE_TRILINEAR,

INTERPOLATE_TETRAHEDRAL,

NB_INTERP_MODE

};

struct rgbvec {

float r, g, b;

};

/* 3D LUT don't often go up to level 32 */

typedef struct LUT3DContext {

uint8_t rgba_map[4];

int step;

struct rgbvec lut[MAX_LEVEL][MAX_LEVEL][MAX_LEVEL];

int lutsize;

} LUT3DContext;

#ifdef _MSC_VER

int strcasecmp(const char *s1, char *s2) {

while (toupper((unsigned char)*s1) == toupper((unsigned char)*s2++))

if (*s1++ == 0x00)

return (0);

return (toupper((unsigned char)*s1) - toupper((unsigned char) *--s2));

}

#endif

static inline float lerpf(float v0, float v1, float f) {

return (v0 + (v1 - v0) * f);

}

static inline struct rgbvec lerp(const struct rgbvec *v0, const struct rgbvec *v1, float f) {

struct rgbvec v = {

lerpf(v0->r, v1->r, f), lerpf(v0->g, v1->g, f), lerpf(v0->b, v1->b, f)

};

return (v);

}

/**

* Get the nearest defined point

static inline struct rgbvec interp_nearest(const LUT3DContext *lut3d,

const struct rgbvec *s) {

return (lut3d->lut[_NEAR(s->r)][_NEAR(s->g)][_NEAR(s->b)]);

}

/**

* Interpolate using the 8 vertices of a cube

* @see /wiki/Trilinear_interpolation

static inline struct rgbvec interp_trilinear(const LUT3DContext *lut3d,

const struct rgbvec *s) {

const int prev[] = {PREV(s->r), PREV(s->g), PREV(s->b)};

const int next[] = {NEXT(s->r), NEXT(s->g), NEXT(s->b)};

const struct rgbvec d = {s->r - prev[0], s->g - prev[1], s->b - prev[2]};

const struct rgbvec c000 = lut3d->lut[prev[0]][prev[1]][prev[2]];

const struct rgbvec c001 = lut3d->lut[prev[0]][prev[1]][next[2]];

const struct rgbvec c010 = lut3d->lut[prev[0]][next[1]][prev[2]];

const struct rgbvec c011 = lut3d->lut[prev[0]][next[1]][next[2]];

const struct rgbvec c100 = lut3d->lut[next[0]][prev[1]][prev[2]];

const struct rgbvec c101 = lut3d->lut[next[0]][prev[1]][next[2]];

const struct rgbvec c110 = lut3d->lut[next[0]][next[1]][prev[2]];

const struct rgbvec c111 = lut3d->lut[next[0]][next[1]][next[2]];

const struct rgbvec c00 = lerp(&c000, &c100, d.r);

const struct rgbvec c10 = lerp(&c010, &c110, d.r);

const struct rgbvec c01 = lerp(&c001, &c101, d.r);

const struct rgbvec c11 = lerp(&c011, &c111, d.r);

const struct rgbvec c0 = lerp(&c00, &c10, d.g);