virtualx-engine/thirdparty/libktx/lib/dfdutils/colourspaces.c
acazuc a00cf02241 Add support for KTX & KTX2 image format
Add support glTF KHR_texture_basisu extension
2023-08-19 10:27:29 +02:00

51 lines
2.5 KiB
C

/* Copyright 2019-2020 The Khronos Group Inc.
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @~English
* @brief Helper functions for colourspaces.
*/
#include <KHR/khr_df.h>
#include "dfd.h"
typedef struct s_PrimaryMapping {
khr_df_primaries_e dfPrimaryEnum;
Primaries primaries;
} sPrimaryMapping;
sPrimaryMapping primaryMap[] = {
{ KHR_DF_PRIMARIES_BT709, { 0.640f,0.330f, 0.300f,0.600f, 0.150f,0.060f, 0.3127f,0.3290f}},
{ KHR_DF_PRIMARIES_BT601_EBU, { 0.640f,0.330f, 0.290f,0.600f, 0.150f,0.060f, 0.3127f,0.3290f}},
{ KHR_DF_PRIMARIES_BT601_SMPTE, { 0.630f,0.340f, 0.310f,0.595f, 0.155f,0.070f, 0.3127f,0.3290f}},
{ KHR_DF_PRIMARIES_BT2020, { 0.708f,0.292f, 0.170f,0.797f, 0.131f,0.046f, 0.3127f,0.3290f}},
{ KHR_DF_PRIMARIES_CIEXYZ, { 1.0f,0.0f, 0.0f,1.0f, 0.0f,0.0f, 0.0f,1.0f}},
{ KHR_DF_PRIMARIES_ACES, { 0.7347f,0.2653f, 0.0f,1.0f, 0.0001f,-0.077f, 0.32168f,0.33767f}},
{ KHR_DF_PRIMARIES_ACESCC, { 0.713f,0.293f, 0.165f,0.830f, 0.128f,0.044f, 0.32168f,0.33767f}},
{ KHR_DF_PRIMARIES_NTSC1953, { 0.67f,0.33f, 0.21f,0.71f, 0.14f,0.08f, 0.310f,0.316f}},
{ KHR_DF_PRIMARIES_PAL525, { 0.630f,0.340f, 0.310f,0.595f, 0.155f,0.070f, 0.3101f,0.3162f}},
{ KHR_DF_PRIMARIES_DISPLAYP3, { 0.6800f,0.3200f, 0.2650f,0.69f, 0.1500f,0.0600f, 0.3127f,0.3290f}},
{ KHR_DF_PRIMARIES_ADOBERGB, { 0.6400f,0.3300f, 0.2100f,0.71f, 0.1500f,0.0600f, 0.3127f,0.3290f}}};
/**
* @brief Map a set of primaries to a KDFS primaries enum.
*
* @param[in] p pointer to a Primaries struct filled in with the primary values.
* @param[in] latitude tolerance to use while matching. A suitable value might be 0.002
* but it depends on the application.
*/
khr_df_primaries_e findMapping(Primaries *p, float latitude) {
unsigned int i;
for (i = 0; i < sizeof(primaryMap)/sizeof(sPrimaryMapping); ++i) {
if (primaryMap[i].primaries.Rx - p->Rx <= latitude && p->Rx - primaryMap[i].primaries.Rx <= latitude &&
primaryMap[i].primaries.Gx - p->Gx <= latitude && p->Gx - primaryMap[i].primaries.Gx <= latitude &&
primaryMap[i].primaries.Bx - p->Bx <= latitude && p->Bx - primaryMap[i].primaries.Bx <= latitude &&
primaryMap[i].primaries.Wx - p->Wx <= latitude && p->Wx - primaryMap[i].primaries.Wx <= latitude) {
return primaryMap[i].dfPrimaryEnum;
}
}
/* No match */
return KHR_DF_PRIMARIES_UNSPECIFIED;
}