/*

 * Copyright (C) 2024 Niklas Haas

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#ifndef SWSCALE_CSPUTILS_H

#define SWSCALE_CSPUTILS_H

#include <stdint.h>

#include <stdbool.h>

#include <math.h>

#include "libavutil/attributes.h"

#include "libavutil/common.h"

#include "libavutil/csp.h"

#include "libavutil/pixfmt.h"

/* Shared constants and helpers for colorspace mapping */

#define fmixf(a, b, x) ((b) * (x) + (a) * (1 - (x)))

static inline float smoothstepf(float edge0, float edge1, float x)

{

    if (edge0 == edge1)

        return x >= edge0;

    x = (x - edge0) / (edge1 - edge0);

    x = av_clipf(x, 0.0f, 1.0f);

    return x * x * (3.0f - 2.0f * x);

}

Unexecuted instantiation: format.c:smoothstepf

Unexecuted instantiation: graph.c:smoothstepf

Unexecuted instantiation: lut3d.c:smoothstepf

Unexecuted instantiation: cms.c:smoothstepf

Unexecuted instantiation: csputils.c:smoothstepf

/* 3x3 matrix math */

typedef struct SwsMatrix3x3 {

    float m[3][3];

} SwsMatrix3x3;

void ff_sws_matrix3x3_mul(SwsMatrix3x3 *a, const SwsMatrix3x3 *b);

void ff_sws_matrix3x3_invert(SwsMatrix3x3 *mat);

void ff_sws_matrix3x3_apply(const SwsMatrix3x3 *mat, float vec[3]);

SwsMatrix3x3 ff_sws_ipt_rgb2lms(const AVColorPrimariesDesc *prim);

SwsMatrix3x3 ff_sws_ipt_lms2rgb(const AVColorPrimariesDesc *prim);

/* Converts to/from XYZ (relative to the given white point, no adaptation) */

SwsMatrix3x3 ff_sws_rgb2xyz(const AVColorPrimariesDesc *prim);

SwsMatrix3x3 ff_sws_xyz2rgb(const AVColorPrimariesDesc *prim);

/* Returns an RGB -> RGB adaptation matrix */

SwsMatrix3x3 ff_sws_get_adaptation(const AVPrimaryCoefficients *prim,

                                   AVWhitepointCoefficients from,

                                   AVWhitepointCoefficients to);

/* Integer math definitions / helpers */

typedef struct v3u8_t {

    uint8_t x, y, z;

} v3u8_t;

typedef struct v2u16_t {

    uint16_t x, y;

} v2u16_t;

typedef struct v3u16_t {

    uint16_t x, y, z;

} v3u16_t;

/* Fast perceptual quantizer */

static const float PQ_M1 = 2610./4096 * 1./4,

                   PQ_M2 = 2523./4096 * 128,

                   PQ_C1 = 3424./4096,

                   PQ_C2 = 2413./4096 * 32,

                   PQ_C3 = 2392./4096 * 32;

enum { PQ_LUT_SIZE = 1024 };

extern const float ff_pq_eotf_lut[PQ_LUT_SIZE+1];

static inline float pq_eotf(float x)

{

    float idxf  = av_clipf(x, 0.0f, 1.0f) * (PQ_LUT_SIZE - 1);

    int ipart   = floorf(idxf);

    float fpart = idxf - ipart;

    return fmixf(ff_pq_eotf_lut[ipart], ff_pq_eotf_lut[ipart + 1], fpart);

}

Unexecuted instantiation: format.c:pq_eotf

Unexecuted instantiation: graph.c:pq_eotf

Unexecuted instantiation: lut3d.c:pq_eotf

Unexecuted instantiation: cms.c:pq_eotf

Unexecuted instantiation: csputils.c:pq_eotf

static inline float pq_oetf(float x)

{

    x = powf(fmaxf(x * 1e-4f, 0.0f), PQ_M1);

    x = (PQ_C1 + PQ_C2 * x) / (1.0f + PQ_C3 * x);

    return powf(x, PQ_M2);

}

Unexecuted instantiation: format.c:pq_oetf

Unexecuted instantiation: graph.c:pq_oetf

Unexecuted instantiation: lut3d.c:pq_oetf

Unexecuted instantiation: cms.c:pq_oetf

Unexecuted instantiation: csputils.c:pq_oetf

/* Misc colorspace math / helpers */

/**

 * Returns true if 'b' is entirely contained in 'a'. Useful for figuring out if

 * colorimetric clipping will occur or not.

 */

bool ff_prim_superset(const AVPrimaryCoefficients *a, const AVPrimaryCoefficients *b);

#endif /* SWSCALE_CSPUTILS_H */