geemili
/
SDL
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Don't assume HDR headroom for HDR10 surfaces 

Applications that support HDR will set the correct values for their content.
main
Sam Lantinga 2024-03-02 15:02:17 -08:00
parent c74f273848
commit 7f9ff6277c
4 changed files with 16 additions and 35 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
include/SDL3/SDL_surface.h
View File

@ -210,27 +210,13 @@ extern DECLSPEC void SDLCALL SDL_DestroySurface(SDL_Surface *surface);
* floating point formats, SDL_COLORSPACE_HDR10 for 10-bit formats,
* SDL_COLORSPACE_SRGB for other RGB surfaces and SDL_COLORSPACE_BT709_FULL
* for YUV surfaces.
* - `SDL_PROP_SURFACE_MAXCLL_NUMBER`: MaxCLL (Maximum Content Light Level)
* indicates the maximum light level of any single pixel (in cd/m2 or nits)
* of the content. MaxCLL is usually measured off the final delivered
* content after mastering. If one uses the full light level of the HDR
* mastering display and adds a hard clip at its maximum value, MaxCLL would
* be equal to the peak luminance of the mastering monitor. This defaults to
* 400 for HDR10 surfaces.
* - `SDL_PROP_SURFACE_MAXFALL_NUMBER`: MaxFALL (Maximum Frame Average Light
* Level) indicates the maximum value of the frame average light level (in
* cd/m2 or nits) of the content. MaxFALL is calculated by averaging the
* decoded luminance values of all the pixels within a frame. MaxFALL is
* usually much lower than MaxCLL.
* - `SDL_PROP_SURFACE_SDR_WHITE_POINT_FLOAT`: for HDR10 and floating point
* surfaces, this defines the value of 100% diffuse white, with higher
* values being displayed in the High Dynamic Range headroom. This defaults
* to 100 for HDR10 surfaces and 1.0 for other surfaces.
* to 203 for HDR10 surfaces and 1.0 for floating point surfaces.
* - `SDL_PROP_SURFACE_HDR_HEADROOM_FLOAT`: for HDR10 and floating point
* surfaces, this defines the maximum dynamic range used by the content, in
* terms of the SDR white point. This defaults to
* SDL_PROP_SURFACE_MAXCLL_NUMBER / SDL_PROP_SURFACE_SDR_WHITE_POINT_FLOAT,
* or 4.0, for HDR10 surfaces.
* terms of the SDR white point. This defaults to 0.0, which disables tone mapping.
* - `SDL_PROP_SURFACE_TONEMAP_OPERATOR_STRING`: the tone mapping operator
* used when compressing from a surface with high dynamic range to another
* with lower dynamic range. Currently this supports "chrome", which uses
@ -250,8 +236,6 @@ extern DECLSPEC void SDLCALL SDL_DestroySurface(SDL_Surface *surface);
extern DECLSPEC SDL_PropertiesID SDLCALL SDL_GetSurfaceProperties(SDL_Surface *surface);
#define SDL_PROP_SURFACE_COLORSPACE_NUMBER "SDL.surface.colorspace"
#define SDL_PROP_SURFACE_MAXCLL_NUMBER "SDL.surface.maxCLL"
#define SDL_PROP_SURFACE_MAXFALL_NUMBER "SDL.surface.maxFALL"
#define SDL_PROP_SURFACE_SDR_WHITE_POINT_FLOAT "SDL.surface.SDR_white_point"
#define SDL_PROP_SURFACE_HDR_HEADROOM_FLOAT "SDL.surface.HDR_headroom"
#define SDL_PROP_SURFACE_TONEMAP_OPERATOR_STRING "SDL.surface.tonemap"

5
src/video/SDL_surface.c
View File

@ -355,11 +355,6 @@ float SDL_GetSurfaceHDRHeadroom(SDL_Surface *surface, SDL_Colorspace colorspace)
} else {
props = 0;
}
if (transfer == SDL_TRANSFER_CHARACTERISTICS_PQ) {
/* The official definition is 10000, but PQ game content is often mastered for 400 or 1000 nits */
const int DEFAULT_PQ_MAXCLL = 1000;
default_value = (float)SDL_GetNumberProperty(props, SDL_PROP_SURFACE_MAXCLL_NUMBER, DEFAULT_PQ_MAXCLL) / SDL_GetSurfaceSDRWhitePoint(surface, colorspace);
}
return SDL_GetFloatProperty(props, SDL_PROP_SURFACE_HDR_HEADROOM_FLOAT, default_value);
}
return 1.0f;

3
test/testcolorspace.c
View File

@ -157,9 +157,6 @@ static SDL_bool ReadPixel(int x, int y, SDL_Color *c)
surface = SDL_RenderReadPixels(renderer, &r);
if (surface) {
/* We don't want to do any HDR -> SDR tone mapping */
SDL_SetFloatProperty(SDL_GetSurfaceProperties(surface), SDL_PROP_SURFACE_HDR_HEADROOM_FLOAT, 0.0f);
if (SDL_ReadSurfacePixel(surface, 0, 0, &c->r, &c->g, &c->b, &c->a) == 0) {
result = SDL_TRUE;
} else {

23
test/testffmpeg.c
View File

@ -436,20 +436,25 @@ static SDL_PropertiesID CreateVideoTextureProperties(AVFrame *frame, Uint32 form
{
AVFrameSideData *pSideData;
SDL_PropertiesID props;
SDL_Colorspace colorspace = GetFrameColorspace(frame);
/* ITU-R BT.2408-6 recommends using an SDR white point of 203 nits, which is more likely for game content */
static const float k_flSDRWhitePoint = 203.0f;
float flMaxLuminance = k_flSDRWhitePoint;
props = SDL_CreateProperties();
SDL_SetNumberProperty(props, SDL_PROP_TEXTURE_CREATE_COLORSPACE_NUMBER, GetFrameColorspace(frame));
SDL_SetNumberProperty(props, SDL_PROP_TEXTURE_CREATE_COLORSPACE_NUMBER, colorspace);
pSideData = av_frame_get_side_data(frame, AV_FRAME_DATA_MASTERING_DISPLAY_METADATA);
if (pSideData) {
/* ITU-R BT.2408-6 recommends using an SDR white point of 203 nits, which is more likely for game content */
static const float k_flSDRWhitePoint = 203.0f;
AVMasteringDisplayMetadata *pMasteringDisplayMetadata = (AVMasteringDisplayMetadata *)pSideData->data;
float flMaxLuminance = (float)pMasteringDisplayMetadata->max_luminance.num / pMasteringDisplayMetadata->max_luminance.den;
if (flMaxLuminance > k_flSDRWhitePoint) {
SDL_SetFloatProperty(props, SDL_PROP_TEXTURE_CREATE_SDR_WHITE_POINT_FLOAT, k_flSDRWhitePoint);
SDL_SetFloatProperty(props, SDL_PROP_TEXTURE_CREATE_HDR_HEADROOM_FLOAT, flMaxLuminance / k_flSDRWhitePoint);
}
flMaxLuminance = (float)pMasteringDisplayMetadata->max_luminance.num / pMasteringDisplayMetadata->max_luminance.den;
} else if (SDL_COLORSPACETRANSFER(colorspace) == SDL_TRANSFER_CHARACTERISTICS_PQ) {
/* The official definition is 10000, but PQ game content is often mastered for 400 or 1000 nits */
flMaxLuminance = 1000.0f;
}
if (flMaxLuminance > k_flSDRWhitePoint) {
SDL_SetFloatProperty(props, SDL_PROP_TEXTURE_CREATE_SDR_WHITE_POINT_FLOAT, k_flSDRWhitePoint);
SDL_SetFloatProperty(props, SDL_PROP_TEXTURE_CREATE_HDR_HEADROOM_FLOAT, flMaxLuminance / k_flSDRWhitePoint);
}
SDL_SetNumberProperty(props, SDL_PROP_TEXTURE_CREATE_FORMAT_NUMBER, format);
SDL_SetNumberProperty(props, SDL_PROP_TEXTURE_CREATE_ACCESS_NUMBER, access);