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fix clamping of hdr pixels to diffuse white #327

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Merged
merged 1 commit into from
Nov 14, 2024
Merged

fix clamping of hdr pixels to diffuse white #327

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36 changes: 18 additions & 18 deletions lib/src/gainmapmath.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -602,39 +602,39 @@ void putYuv444Pixel(uhdr_raw_image_t* image, size_t x, size_t y, Color& pixel) {
// Color space conversions

Color bt709ToP3(Color e) {
return {{{clampPixelFloat(0.82254f * e.r + 0.17755f * e.g + 0.00006f * e.b),
clampPixelFloat(0.03312f * e.r + 0.96684f * e.g + -0.00001f * e.b),
clampPixelFloat(0.01706f * e.r + 0.07240f * e.g + 0.91049f * e.b)}}};
return {{{0.82254f * e.r + 0.17755f * e.g + 0.00006f * e.b,
0.03312f * e.r + 0.96684f * e.g + -0.00001f * e.b,
0.01706f * e.r + 0.07240f * e.g + 0.91049f * e.b}}};
}

Color bt709ToBt2100(Color e) {
return {{{clampPixelFloat(0.62740f * e.r + 0.32930f * e.g + 0.04332f * e.b),
clampPixelFloat(0.06904f * e.r + 0.91958f * e.g + 0.01138f * e.b),
clampPixelFloat(0.01636f * e.r + 0.08799f * e.g + 0.89555f * e.b)}}};
return {{{0.62740f * e.r + 0.32930f * e.g + 0.04332f * e.b,
0.06904f * e.r + 0.91958f * e.g + 0.01138f * e.b,
0.01636f * e.r + 0.08799f * e.g + 0.89555f * e.b}}};
}

Color p3ToBt709(Color e) {
return {{{clampPixelFloat(1.22482f * e.r + -0.22490f * e.g + -0.00007f * e.b),
clampPixelFloat(-0.04196f * e.r + 1.04199f * e.g + 0.00001f * e.b),
clampPixelFloat(-0.01961f * e.r + -0.07865f * e.g + 1.09831f * e.b)}}};
return {{{1.22482f * e.r + -0.22490f * e.g + -0.00007f * e.b,
-0.04196f * e.r + 1.04199f * e.g + 0.00001f * e.b,
-0.01961f * e.r + -0.07865f * e.g + 1.09831f * e.b}}};
}

Color p3ToBt2100(Color e) {
return {{{clampPixelFloat(0.75378f * e.r + 0.19862f * e.g + 0.04754f * e.b),
clampPixelFloat(0.04576f * e.r + 0.94177f * e.g + 0.01250f * e.b),
clampPixelFloat(-0.00121f * e.r + 0.01757f * e.g + 0.98359f * e.b)}}};
return {{{0.75378f * e.r + 0.19862f * e.g + 0.04754f * e.b,
0.04576f * e.r + 0.94177f * e.g + 0.01250f * e.b,
-0.00121f * e.r + 0.01757f * e.g + 0.98359f * e.b}}};
}

Color bt2100ToBt709(Color e) {
return {{{clampPixelFloat(1.66045f * e.r + -0.58764f * e.g + -0.07286f * e.b),
clampPixelFloat(-0.12445f * e.r + 1.13282f * e.g + -0.00837f * e.b),
clampPixelFloat(-0.01811f * e.r + -0.10057f * e.g + 1.11878f * e.b)}}};
return {{{1.66045f * e.r + -0.58764f * e.g + -0.07286f * e.b,
-0.12445f * e.r + 1.13282f * e.g + -0.00837f * e.b,
-0.01811f * e.r + -0.10057f * e.g + 1.11878f * e.b}}};
}

Color bt2100ToP3(Color e) {
return {{{clampPixelFloat(1.34369f * e.r + -0.28223f * e.g + -0.06135f * e.b),
clampPixelFloat(-0.06533f * e.r + 1.07580f * e.g + -0.01051f * e.b),
clampPixelFloat(0.00283f * e.r + -0.01957f * e.g + 1.01679f * e.b)}}};
return {{{1.34369f * e.r + -0.28223f * e.g + -0.06135f * e.b,
-0.06533f * e.r + 1.07580f * e.g + -0.01051f * e.b,
0.00283f * e.r + -0.01957f * e.g + 1.01679f * e.b}}};
}

// All of these conversions are derived from the respective input YUV->RGB conversion followed by
Expand Down
8 changes: 8 additions & 0 deletions lib/src/jpegr.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -697,6 +697,9 @@ uhdr_error_info_t JpegR::generateGainMap(uhdr_raw_image_t* sdr_intent, uhdr_raw_
const bool isSdrIntentRgb = isPixelFormatRgb(sdr_intent->fmt);
const float hdrSampleToNitsFactor =
hdr_intent->ct == UHDR_CT_LINEAR ? kSdrWhiteNits : hdr_white_nits;
ColorTransformFn clampPixel = hdr_intent->ct == UHDR_CT_LINEAR
? static_cast<ColorTransformFn>(clampPixelFloatLinear)
: static_cast<ColorTransformFn>(clampPixelFloat);
while (jobQueue.dequeueJob(rowStart, rowEnd)) {
for (size_t y = rowStart; y < rowEnd; ++y) {
for (size_t x = 0; x < dest->w; ++x) {
Expand Down Expand Up @@ -727,6 +730,7 @@ uhdr_error_info_t JpegR::generateGainMap(uhdr_raw_image_t* sdr_intent, uhdr_raw_
Color hdr_rgb = hdrInvOetf(hdr_rgb_gamma);
hdr_rgb = hdrOotfFn(hdr_rgb, hdrLuminanceFn);
hdr_rgb = hdrGamutConversionFn(hdr_rgb);
hdr_rgb = clampPixel(hdr_rgb);

if (mUseMultiChannelGainMap) {
Color sdr_rgb_nits = sdr_rgb * kSdrWhiteNits;
Expand Down Expand Up @@ -803,6 +807,9 @@ uhdr_error_info_t JpegR::generateGainMap(uhdr_raw_image_t* sdr_intent, uhdr_raw_
const bool isSdrIntentRgb = isPixelFormatRgb(sdr_intent->fmt);
const float hdrSampleToNitsFactor =
hdr_intent->ct == UHDR_CT_LINEAR ? kSdrWhiteNits : hdr_white_nits;
ColorTransformFn clampPixel = hdr_intent->ct == UHDR_CT_LINEAR
? static_cast<ColorTransformFn>(clampPixelFloatLinear)
: static_cast<ColorTransformFn>(clampPixelFloat);
float gainmap_min_th[3] = {127.0f, 127.0f, 127.0f};
float gainmap_max_th[3] = {-128.0f, -128.0f, -128.0f};

Expand Down Expand Up @@ -836,6 +843,7 @@ uhdr_error_info_t JpegR::generateGainMap(uhdr_raw_image_t* sdr_intent, uhdr_raw_
Color hdr_rgb = hdrInvOetf(hdr_rgb_gamma);
hdr_rgb = hdrOotfFn(hdr_rgb, hdrLuminanceFn);
hdr_rgb = hdrGamutConversionFn(hdr_rgb);
hdr_rgb = clampPixel(hdr_rgb);

if (mUseMultiChannelGainMap) {
Color sdr_rgb_nits = sdr_rgb * kSdrWhiteNits;
Expand Down
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