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ram-mohanram-mohan
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update weights used in rgb to yuv conversion equations
Display P3 color space is using bt601 equations. Updated these to use the ones derived using p3 primaries Test: ./ultrahdr_unit_test Change-Id: I9306fe13c4651c7d55a830d0597924a8d26d2745
1 parent d52a0d1 commit 7fe4283

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8 files changed

+300
-129
lines changed

8 files changed

+300
-129
lines changed

‎examples/ultrahdr_app.cpp‎

Lines changed: 19 additions & 19 deletions
Original file line numberDiff line numberDiff line change
@@ -32,23 +32,23 @@
3232

3333
#include "ultrahdr_api.h"
3434

35-
const float BT601YUVtoRGBMatrix[9] = {
36-
1.f, 0.f, 1.402f, 1.f, (-0.202008f / 0.587f), (-0.419198f / 0.587f), 1.0f, 1.772f, 0.0f};
35+
const float DisplayP3YUVtoRGBMatrix[9] = {
36+
1.f, 0.f, 1.542f, 1.f, (-0.146023f / 0.6917f), (-0.353118f / 0.6917f), 1.0f, 1.8414f, 0.0f};
3737
const float BT709YUVtoRGBMatrix[9] = {
3838
1.f, 0.f, 1.5748f, 1.f, (-0.13397432f / 0.7152f), (-0.33480248f / 0.7152f),
3939
1.0f, 1.8556f, 0.0f};
4040
const float BT2020YUVtoRGBMatrix[9] = {
4141
1.f, 0.f, 1.4746f, 1.f, (-0.11156702f / 0.6780f), (-0.38737742f / 0.6780f), 1.f, 1.8814f, 0.f};
4242

43-
const float BT601RGBtoYUVMatrix[9] = {0.299f,
44-
0.587f,
45-
0.114f,
46-
(-0.299f / 1.772f),
47-
(-0.587f / 1.772f),
48-
0.5f,
49-
0.5f,
50-
(-0.587f / 1.402f),
51-
(-0.114f / 1.402f)};
43+
const float DisplayP3RGBtoYUVMatrix[9] = {0.229f,
44+
0.6917f,
45+
0.0793f,
46+
(-0.229f / 1.8414f),
47+
(-0.6917f / 1.8414f),
48+
0.5f,
49+
0.5f,
50+
(-0.6917f / 1.542f),
51+
(-0.0793f / 1.542f)};
5252
const float BT709RGBtoYUVMatrix[9] = {0.2126f,
5353
0.7152f,
5454
0.0722f,
@@ -892,7 +892,7 @@ bool UltraHdrAppInput::convertP010ToRGBImage() {
892892
} else if (mHdrCg == UHDR_CG_BT_2100) {
893893
coeffs = BT2020YUVtoRGBMatrix;
894894
} else if (mHdrCg == UHDR_CG_DISPLAY_P3) {
895-
coeffs = BT601YUVtoRGBMatrix;
895+
coeffs = DisplayP3YUVtoRGBMatrix;
896896
} else {
897897
std::cerr << "color matrix not present for gamut " << mHdrCg << " using BT2020Matrix"
898898
<< std::endl;
@@ -984,15 +984,15 @@ bool UltraHdrAppInput::convertYuv420ToRGBImage() {
984984
uint8_t* u = static_cast<uint8_t*>(mRawYuv420Image.planes[UHDR_PLANE_U]);
985985
uint8_t* v = static_cast<uint8_t*>(mRawYuv420Image.planes[UHDR_PLANE_V]);
986986

987-
const float* coeffs = BT601YUVtoRGBMatrix;
987+
const float* coeffs = BT709YUVtoRGBMatrix;
988988
if (mSdrCg == UHDR_CG_BT_709) {
989989
coeffs = BT709YUVtoRGBMatrix;
990990
} else if (mSdrCg == UHDR_CG_BT_2100) {
991991
coeffs = BT2020YUVtoRGBMatrix;
992992
} else if (mSdrCg == UHDR_CG_DISPLAY_P3) {
993-
coeffs = BT601YUVtoRGBMatrix;
993+
coeffs = DisplayP3YUVtoRGBMatrix;
994994
} else {
995-
std::cerr << "color matrix not present for gamut " << mSdrCg << " using BT601Matrix"
995+
std::cerr << "color matrix not present for gamut " << mSdrCg << " using BT709Matrix"
996996
<< std::endl;
997997
}
998998
for (size_t i = 0; i < mRawYuv420Image.h; i++) {
@@ -1054,16 +1054,16 @@ bool UltraHdrAppInput::convertRgba8888ToYUV444Image() {
10541054
uint8_t* uData = static_cast<uint8_t*>(mDecodedUhdrYuv444Image.planes[UHDR_PLANE_U]);
10551055
uint8_t* vData = static_cast<uint8_t*>(mDecodedUhdrYuv444Image.planes[UHDR_PLANE_V]);
10561056

1057-
const float* coeffs = BT601RGBtoYUVMatrix;
1057+
const float* coeffs = BT709RGBtoYUVMatrix;
10581058
if (mDecodedUhdrRgbImage.cg == UHDR_CG_BT_709) {
10591059
coeffs = BT709RGBtoYUVMatrix;
10601060
} else if (mDecodedUhdrRgbImage.cg == UHDR_CG_BT_2100) {
10611061
coeffs = BT2020RGBtoYUVMatrix;
10621062
} else if (mDecodedUhdrRgbImage.cg == UHDR_CG_DISPLAY_P3) {
1063-
coeffs = BT601RGBtoYUVMatrix;
1063+
coeffs = DisplayP3RGBtoYUVMatrix;
10641064
} else {
10651065
std::cerr << "color matrix not present for gamut " << mDecodedUhdrRgbImage.cg
1066-
<< " using BT601Matrix" << std::endl;
1066+
<< " using BT709Matrix" << std::endl;
10671067
}
10681068

10691069
for (size_t i = 0; i < mDecodedUhdrRgbImage.h; i++) {
@@ -1108,7 +1108,7 @@ bool UltraHdrAppInput::convertRgba1010102ToYUV444Image() {
11081108
} else if (mDecodedUhdrRgbImage.cg == UHDR_CG_BT_2100) {
11091109
coeffs = BT2020RGBtoYUVMatrix;
11101110
} else if (mDecodedUhdrRgbImage.cg == UHDR_CG_DISPLAY_P3) {
1111-
coeffs = BT601RGBtoYUVMatrix;
1111+
coeffs = DisplayP3RGBtoYUVMatrix;
11121112
} else {
11131113
std::cerr << "color matrix not present for gamut " << mDecodedUhdrRgbImage.cg
11141114
<< " using BT2020Matrix" << std::endl;

‎lib/include/ultrahdr/gainmapmath.h‎

Lines changed: 22 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -347,6 +347,13 @@ Color pqInvOetfLUT(Color e_gamma);
347347
constexpr int32_t kPqInvOETFPrecision = 12;
348348
constexpr int32_t kPqInvOETFNumEntries = 1 << kPqInvOETFPrecision;
349349

350+
////////////////////////////////////////////////////////////////////////////////
351+
// BT.601 transformations
352+
353+
// BT.601 rgb <-> yuv conversion
354+
Color bt601RgbToYuv(Color e_gamma);
355+
Color bt601YuvToRgb(Color e_gamma);
356+
350357
// util class to prepare look up tables for oetf/eotf functions
351358
class LookUpTable {
352359
public:
@@ -415,20 +422,26 @@ Color bt2100ToP3(Color e);
415422

416423
// convert between yuv encodings
417424
extern const std::array<float, 9> kYuvBt709ToBt601;
425+
extern const std::array<float, 9> kYuvBt709ToDisplayP3;
418426
extern const std::array<float, 9> kYuvBt709ToBt2100;
419-
extern const std::array<float, 9> kYuvBt601ToBt709;
420-
extern const std::array<float, 9> kYuvBt601ToBt2100;
421-
extern const std::array<float, 9> kYuvBt2100ToBt709;
427+
extern const std::array<float, 9> kYuvDisplayP3ToBt601;
428+
extern const std::array<float, 9> kYuvDisplayP3ToBt709;
429+
extern const std::array<float, 9> kYuvDisplayP3ToBt2100;
422430
extern const std::array<float, 9> kYuvBt2100ToBt601;
431+
extern const std::array<float, 9> kYuvBt2100ToBt709;
432+
extern const std::array<float, 9> kYuvBt2100ToDisplayP3;
423433

424434
#if (defined(UHDR_ENABLE_INTRINSICS) && (defined(__ARM_NEON__) || defined(__ARM_NEON)))
425435

426436
extern const int16_t kYuv709To601_coeffs_neon[8];
437+
extern const int16_t kYuv709ToP3_coeffs_neon[8];
427438
extern const int16_t kYuv709To2100_coeffs_neon[8];
428-
extern const int16_t kYuv601To709_coeffs_neon[8];
429-
extern const int16_t kYuv601To2100_coeffs_neon[8];
430-
extern const int16_t kYuv2100To709_coeffs_neon[8];
439+
extern const int16_t kYuvP3To601_coeffs_neon[8];
440+
extern const int16_t kYuvP3To709_coeffs_neon[8];
441+
extern const int16_t kYuvP3To2100_coeffs_neon[8];
431442
extern const int16_t kYuv2100To601_coeffs_neon[8];
443+
extern const int16_t kYuv2100To709_coeffs_neon[8];
444+
extern const int16_t kYuv2100ToP3_coeffs_neon[8];
432445

433446
/*
434447
* The Y values are provided at half the width of U & V values to allow use of the widening
@@ -608,10 +621,11 @@ std::unique_ptr<uhdr_raw_image_ext_t> copy_raw_image(uhdr_raw_image_t* src);
608621
uhdr_error_info_t copy_raw_image(uhdr_raw_image_t* src, uhdr_raw_image_t* dst);
609622

610623
std::unique_ptr<uhdr_raw_image_ext_t> convert_raw_input_to_ycbcr(
611-
uhdr_raw_image_t* src, bool chroma_sampling_enabled = false);
624+
uhdr_raw_image_t* src, bool use_bt601 = false, bool chroma_sampling_enabled = false);
612625

613626
#if (defined(UHDR_ENABLE_INTRINSICS) && (defined(__ARM_NEON__) || defined(__ARM_NEON)))
614-
std::unique_ptr<uhdr_raw_image_ext_t> convert_raw_input_to_ycbcr_neon(uhdr_raw_image_t* src);
627+
std::unique_ptr<uhdr_raw_image_ext_t> convert_raw_input_to_ycbcr_neon(uhdr_raw_image_t* src,
628+
bool use_bt601 = false);
615629
#endif
616630

617631
bool floatToSignedFraction(float v, int32_t* numerator, uint32_t* denominator);

‎lib/include/ultrahdr/ultrahdrcommon.h‎

Lines changed: 2 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -159,6 +159,8 @@
159159

160160
static const uhdr_error_info_t g_no_error = {UHDR_CODEC_OK, 0, ""};
161161

162+
static const int UHDR_CG_BT_601 = 3; /**< BT.601 */
163+
162164
namespace ultrahdr {
163165

164166
// ===============================================================================================

‎lib/src/dsp/arm/gainmapmath_neon.cpp‎

Lines changed: 70 additions & 30 deletions
Original file line numberDiff line numberDiff line change
@@ -35,47 +35,68 @@ namespace ultrahdr {
3535
// {Y1, Y2, U1, U2, V1, V2, 0, 0}
3636

3737
// Yuv Bt709 -> Yuv Bt601
38-
// Y' = (1.0f * Y) + ( 0.101579f * U) + ( 0.196076f * V)
39-
// U' = (0.0f * Y) + ( 0.989854f * U) + (-0.110653f * V)
40-
// V' = (0.0f * Y) + (-0.072453f * U) + ( 0.983398f * V)
38+
// Y' = (1.0 * Y) + ( 0.101579 * U) + ( 0.196076 * V)
39+
// U' = (0.0 * Y) + ( 0.989854 * U) + (-0.110653 * V)
40+
// V' = (0.0 * Y) + (-0.072453 * U) + ( 0.983398 * V)
4141
ALIGNED(16)
4242
const int16_t kYuv709To601_coeffs_neon[8] = {1664, 3213, 16218, -1813, -1187, 16112, 0, 0};
4343

44+
// Yuv Bt709 -> Display P3
45+
// Y' = (1.0 * Y) + ( 0.017545 * U) + ( 0.03677 * V)
46+
// U' = (0.0 * Y) + ( 0.998169 * U) + (-0.019968 * V)
47+
// V' = (0.0 * Y) + (-0.011378 * U) + ( 0.997393 * V)
48+
ALIGNED(16)
49+
const int16_t kYuv709ToP3_coeffs_neon[8] = {287, 602, 16354, -327, -186, 16341, 0, 0};
50+
4451
// Yuv Bt709 -> Yuv Bt2100
4552
// Y' = (1.0f * Y) + (-0.016969f * U) + ( 0.096312f * V)
4653
// U' = (0.0f * Y) + ( 0.995306f * U) + (-0.051192f * V)
4754
// V' = (0.0f * Y) + ( 0.011507f * U) + ( 1.002637f * V)
4855
ALIGNED(16)
4956
const int16_t kYuv709To2100_coeffs_neon[8] = {-278, 1578, 16307, -839, 189, 16427, 0, 0};
5057

51-
// Yuv Bt601 -> Yuv Bt709
52-
// Y' = (1.0f * Y) + (-0.118188f * U) + (-0.212685f * V),
53-
// U' = (0.0f * Y) + ( 1.018640f * U) + ( 0.114618f * V),
54-
// V' = (0.0f * Y) + ( 0.075049f * U) + ( 1.025327f * V);
58+
// Yuv Display P3 -> Yuv Bt601
59+
// Y' = (1.0 * Y) + ( 0.086028 * U) + ( 0.161445 * V)
60+
// U' = (0.0 * Y) + ( 0.990631 * U) + (-0.091109 * V)
61+
// V' = (0.0 * Y) + (-0.061361 * U) + ( 0.98474 * V)
5562
ALIGNED(16)
56-
const int16_t kYuv601To709_coeffs_neon[8] = {-1936, -3485, 16689, 1878, 1230, 16799, 0, 0};
63+
const int16_t kYuvP3To601_coeffs_neon[8] = {1409, 2645, 16230, -1493, -1005, 16134, 0, 0};
5764

58-
// Yuv Bt601 -> Yuv Bt2100
59-
// Y' = (1.0f * Y) + (-0.128245f * U) + (-0.115879f * V)
60-
// U' = (0.0f * Y) + ( 1.010016f * U) + ( 0.061592f * V)
61-
// V' = (0.0f * Y) + ( 0.086969f * U) + ( 1.029350f * V)
65+
// Yuv Display P3 -> Yuv Bt709
66+
// Y' = (1.0 * Y) + (-0.018002 * U) + (-0.037226 * V)
67+
// U' = (0.0 * Y) + ( 1.002063 * U) + ( 0.020061 * V)
68+
// V' = (0.0 * Y) + ( 0.011431 * U) + ( 1.002843 * V)
6269
ALIGNED(16)
63-
const int16_t kYuv601To2100_coeffs_neon[8] = {-2101, -1899, 16548, 1009, 1425, 16865, 0, 0};
70+
const int16_t kYuvP3To709_coeffs_neon[8] = {-295, -610, 16418, 329, 187, 16431, 0, 0};
6471

65-
// Yuv Bt2100 -> Yuv Bt709
66-
// Y' = (1.0f * Y) + ( 0.018149f * U) + (-0.095132f * V)
67-
// U' = (0.0f * Y) + ( 1.004123f * U) + ( 0.051267f * V)
68-
// V' = (0.0f * Y) + (-0.011524f * U) + ( 0.996782f * V)
72+
// Yuv Display P3 -> Yuv Bt2100
73+
// Y' = (1.0 * Y) + (-0.033905 * U) + ( 0.059019 * V)
74+
// U' = (0.0 * Y) + ( 0.996774 * U) + ( -0.03137 * V)
75+
// V' = (0.0 * Y) + ( 0.022992 * U) + ( 1.005718 * V)
6976
ALIGNED(16)
70-
const int16_t kYuv2100To709_coeffs_neon[8] = {297, -1559, 16452, 840, -189, 16331, 0, 0};
77+
const int16_t kYuvP3To2100_coeffs_neon[8] = {-555, 967, 16331, -514, 377, 16478, 0, 0};
7178

7279
// Yuv Bt2100 -> Yuv Bt601
73-
// Y' = (1.0f * Y) + ( 0.117887f * U) + ( 0.105521f * V)
74-
// U' = (0.0f * Y) + ( 0.995211f * U) + (-0.059549f * V)
75-
// V' = (0.0f * Y) + (-0.084085f * U) + ( 0.976518f * V)
80+
// Y' = (1.0 * Y) + ( 0.117887 * U) + ( 0.105521 * V)
81+
// U' = (0.0 * Y) + ( 0.995211 * U) + (-0.059549 * V)
82+
// V' = (0.0 * Y) + (-0.084085 * U) + ( 0.976518 * V)
7683
ALIGNED(16)
7784
const int16_t kYuv2100To601_coeffs_neon[8] = {1931, 1729, 16306, -976, -1378, 15999, 0, 0};
7885

86+
// Yuv Bt2100 -> Yuv Bt709
87+
// Y' = (1.0 * Y) + ( 0.018149 * U) + (-0.095132 * V)
88+
// U' = (0.0 * Y) + ( 1.004123 * U) + ( 0.051267 * V)
89+
// V' = (0.0 * Y) + (-0.011524 * U) + ( 0.996782 * V)
90+
ALIGNED(16)
91+
const int16_t kYuv2100To709_coeffs_neon[8] = {297, -1559, 16452, 840, -189, 16331, 0, 0};
92+
93+
// Yuv Bt2100 -> Yuv Display P3
94+
// Y' = (1.0 * Y) + ( 0.035343 * U) + ( -0.057581 * V)
95+
// U' = (0.0 * Y) + ( 1.002515 * U) + ( 0.03127 * V)
96+
// V' = (0.0 * Y) + (-0.022919 * U) + ( 0.9936 * V)
97+
ALIGNED(16)
98+
const int16_t kYuv2100ToP3_coeffs_neon[8] = {579, -943, 16425, 512, -376, 16279, 0, 0};
99+
79100
static inline int16x8_t yConversion_neon(uint8x8_t y, int16x8_t u, int16x8_t v, int16x8_t coeffs) {
80101
int32x4_t lo = vmull_lane_s16(vget_low_s16(u), vget_low_s16(coeffs), 0);
81102
int32x4_t hi = vmull_lane_s16(vget_high_s16(u), vget_low_s16(coeffs), 0);
@@ -240,11 +261,14 @@ uhdr_error_info_t convertYuv_neon(uhdr_raw_image_t* image, uhdr_color_gamut_t sr
240261

241262
switch (src_encoding) {
242263
case UHDR_CG_BT_709:
243-
switch (dst_encoding) {
264+
switch ((int)dst_encoding) {
265+
case UHDR_CG_BT_601:
266+
coeffs = kYuv709To601_coeffs_neon;
267+
break;
244268
case UHDR_CG_BT_709:
245269
return status;
246270
case UHDR_CG_DISPLAY_P3:
247-
coeffs = kYuv709To601_coeffs_neon;
271+
coeffs = kYuv709ToP3_coeffs_neon;
248272
break;
249273
case UHDR_CG_BT_2100:
250274
coeffs = kYuv709To2100_coeffs_neon;
@@ -258,14 +282,17 @@ uhdr_error_info_t convertYuv_neon(uhdr_raw_image_t* image, uhdr_color_gamut_t sr
258282
}
259283
break;
260284
case UHDR_CG_DISPLAY_P3:
261-
switch (dst_encoding) {
285+
switch ((int)dst_encoding) {
286+
case UHDR_CG_BT_601:
287+
coeffs = kYuvP3To601_coeffs_neon;
288+
break;
262289
case UHDR_CG_BT_709:
263-
coeffs = kYuv601To709_coeffs_neon;
290+
coeffs = kYuvP3To709_coeffs_neon;
264291
break;
265292
case UHDR_CG_DISPLAY_P3:
266293
return status;
267294
case UHDR_CG_BT_2100:
268-
coeffs = kYuv601To2100_coeffs_neon;
295+
coeffs = kYuvP3To2100_coeffs_neon;
269296
break;
270297
default:
271298
status.error_code = UHDR_CODEC_INVALID_PARAM;
@@ -276,12 +303,15 @@ uhdr_error_info_t convertYuv_neon(uhdr_raw_image_t* image, uhdr_color_gamut_t sr
276303
}
277304
break;
278305
case UHDR_CG_BT_2100:
279-
switch (dst_encoding) {
306+
switch ((int)dst_encoding) {
307+
case UHDR_CG_BT_601:
308+
coeffs = kYuv2100To601_coeffs_neon;
309+
break;
280310
case UHDR_CG_BT_709:
281311
coeffs = kYuv2100To709_coeffs_neon;
282312
break;
283313
case UHDR_CG_DISPLAY_P3:
284-
coeffs = kYuv2100To601_coeffs_neon;
314+
coeffs = kYuv2100ToP3_coeffs_neon;
285315
break;
286316
case UHDR_CG_BT_2100:
287317
return status;
@@ -323,6 +353,13 @@ uhdr_error_info_t convertYuv_neon(uhdr_raw_image_t* image, uhdr_color_gamut_t sr
323353
// In the 3x3 conversion matrix, 0.5 is duplicated. But represented as only one entry in lut leaving
324354
// with an array size of 8 elements.
325355

356+
// RGB Bt601 -> Yuv Bt601
357+
// Y = 0.299 * R + 0.587 * G + 0.114 * B
358+
// U = -0.168735892 * R + -0.331264108 * G + 0.5 * B
359+
// V = 0.5 * R + -0.418687589 * G + -0.081312411 * B
360+
ALIGNED(16)
361+
const uint16_t kRgb601ToYuv_coeffs_neon[8] = {4899, 9617, 1868, 2765, 5427, 8192, 6860, 1332};
362+
326363
// RGB Bt709 -> Yuv Bt709
327364
// Y = 0.212639 * R + 0.715169 * G + 0.072192 * B
328365
// U = -0.114592135 * R + -0.385407865 * G + 0.5 * B
@@ -454,12 +491,15 @@ static void ConvertRgba8888ToYuv444_neon(uhdr_raw_image_t* src, uhdr_raw_image_t
454491
} while (++h < src->h);
455492
}
456493

457-
std::unique_ptr<uhdr_raw_image_ext_t> convert_raw_input_to_ycbcr_neon(uhdr_raw_image_t* src) {
494+
std::unique_ptr<uhdr_raw_image_ext_t> convert_raw_input_to_ycbcr_neon(uhdr_raw_image_t* src,
495+
bool use_bt601) {
458496
if (src->fmt == UHDR_IMG_FMT_32bppRGBA8888) {
459497
std::unique_ptr<uhdr_raw_image_ext_t> dst = nullptr;
460498
const uint16_t* coeffs_ptr = nullptr;
461499

462-
if (src->cg == UHDR_CG_BT_709) {
500+
if (use_bt601) {
501+
coeffs_ptr = kRgb601ToYuv_coeffs_neon;
502+
} else if (src->cg == UHDR_CG_BT_709) {
463503
coeffs_ptr = kRgb709ToYuv_coeffs_neon;
464504
} else if (src->cg == UHDR_CG_BT_2100) {
465505
coeffs_ptr = kRgbDispP3ToYuv_coeffs_neon;

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