From 82811d070659020b703d02ceeed79540d43a6c82 Mon Sep 17 00:00:00 2001 From: Rostislav Vasilikhin Date: Wed, 5 Jul 2017 20:36:30 +0300 Subject: [PATCH] Luv: singularities fixed --- modules/imgproc/src/color.cpp | 84 +++++++++++++++++++++++------------ 1 file changed, 55 insertions(+), 29 deletions(-) diff --git a/modules/imgproc/src/color.cpp b/modules/imgproc/src/color.cpp index 488bdc1cc5..4f27671ff3 100644 --- a/modules/imgproc/src/color.cpp +++ b/modules/imgproc/src/color.cpp @@ -6495,7 +6495,7 @@ struct RGB2Luv_f coeffs[i*3] + coeffs[i*3+1] + coeffs[i*3+2] < 1.5f ); } - float d = 1.f/(whitept[0] + whitept[1]*15 + whitept[2]*3); + float d = 1.f/std::max(whitept[0] + whitept[1]*15 + whitept[2]*3, FLT_EPSILON); un = 4*whitept[0]*d*13; vn = 9*whitept[1]*d*13; @@ -6755,9 +6755,9 @@ struct Luv2RGB_f coeffs[i+blueIdx*3] = _coeffs[i+6]; } - float d = 1.f/(whitept[0] + whitept[1]*15 + whitept[2]*3); - un = 4*whitept[0]*d; - vn = 9*whitept[1]*d; + float d = 1.f/std::max(whitept[0] + whitept[1]*15 + whitept[2]*3, FLT_EPSILON); + un = 4*13*whitept[0]*d; + vn = 9*13*whitept[1]*d; #if CV_SSE2 haveSIMD = checkHardwareSupport(CV_CPU_SSE2); #endif @@ -6769,23 +6769,42 @@ struct Luv2RGB_f void process(__m128& v_l0, __m128& v_l1, __m128& v_u0, __m128& v_u1, __m128& v_v0, __m128& v_v1) const { - __m128 v_y0 = _mm_mul_ps(_mm_add_ps(v_l0, _mm_set1_ps(16.0f)), _mm_set1_ps(1.f/116.f)); - __m128 v_y1 = _mm_mul_ps(_mm_add_ps(v_l1, _mm_set1_ps(16.0f)), _mm_set1_ps(1.f/116.f)); - v_y0 = _mm_mul_ps(_mm_mul_ps(v_y0, v_y0), v_y0); - v_y1 = _mm_mul_ps(_mm_mul_ps(v_y1, v_y1), v_y1); - __m128 v_d0 = _mm_div_ps(_mm_set1_ps(1.f/13.f), v_l0); - __m128 v_d1 = _mm_div_ps(_mm_set1_ps(1.f/13.f), v_l1); - v_u0 = _mm_mul_ps(_mm_add_ps(_mm_mul_ps(v_u0, v_d0), _mm_set1_ps(un)), _mm_set1_ps(3.f)); - v_u1 = _mm_mul_ps(_mm_add_ps(_mm_mul_ps(v_u1, v_d1), _mm_set1_ps(un)), _mm_set1_ps(3.f)); - v_v0 = _mm_add_ps(_mm_mul_ps(v_v0, v_d0), _mm_set1_ps(vn)); - v_v1 = _mm_add_ps(_mm_mul_ps(v_v1, v_d1), _mm_set1_ps(vn)); - __m128 v_iv0 = _mm_div_ps(_mm_set1_ps(0.25f), v_v0); - __m128 v_iv1 = _mm_div_ps(_mm_set1_ps(0.25f), v_v1); - __m128 v_x0 = _mm_mul_ps(_mm_mul_ps(_mm_set1_ps(3.f), v_u0), v_iv0); - __m128 v_x1 = _mm_mul_ps(_mm_mul_ps(_mm_set1_ps(3.f), v_u1), v_iv1); - __m128 v_z0 = _mm_mul_ps(_mm_sub_ps(_mm_sub_ps(_mm_set1_ps(12.f), v_u0), _mm_mul_ps(_mm_set1_ps(20.f), v_v0)), v_iv0); - __m128 v_z1 = _mm_mul_ps(_mm_sub_ps(_mm_sub_ps(_mm_set1_ps(12.f), v_u1), _mm_mul_ps(_mm_set1_ps(20.f), v_v1)), v_iv1); + // L*(3./29.)^3 + __m128 v_y00 = _mm_mul_ps(v_l0, _mm_set1_ps(1.0f/903.3f)); + __m128 v_y01 = _mm_mul_ps(v_l1, _mm_set1_ps(1.0f/903.3f)); + // ((L + 16)/116)^3 + __m128 v_y10 = _mm_mul_ps(_mm_add_ps(v_l0, _mm_set1_ps(16.0f)), _mm_set1_ps(1.f/116.f)); + __m128 v_y11 = _mm_mul_ps(_mm_add_ps(v_l1, _mm_set1_ps(16.0f)), _mm_set1_ps(1.f/116.f)); + v_y10 = _mm_mul_ps(_mm_mul_ps(v_y10, v_y10), v_y10); + v_y11 = _mm_mul_ps(_mm_mul_ps(v_y11, v_y11), v_y11); + // Y = (L <= 8) ? Y0 : Y1; + __m128 v_cmpl0 = _mm_cmplt_ps(v_l0, _mm_set1_ps(8.f)); + __m128 v_cmpl1 = _mm_cmplt_ps(v_l1, _mm_set1_ps(8.f)); + v_y00 = _mm_and_ps(v_cmpl0, v_y00); + v_y01 = _mm_and_ps(v_cmpl1, v_y01); + v_y10 = _mm_andnot_ps(v_cmpl0, v_y10); + v_y11 = _mm_andnot_ps(v_cmpl1, v_y11); + __m128 v_y0 = _mm_or_ps(v_y00, v_y10); + __m128 v_y1 = _mm_or_ps(v_y01, v_y11); + // up = 3*(u + L*_un); + __m128 v_up0 = _mm_mul_ps(_mm_set1_ps(3.f), _mm_add_ps(v_u0, _mm_mul_ps(v_l0, _mm_set1_ps(un)))); + __m128 v_up1 = _mm_mul_ps(_mm_set1_ps(3.f), _mm_add_ps(v_u1, _mm_mul_ps(v_l1, _mm_set1_ps(un)))); + // vp = 0.25/(v + L*_vn); + __m128 v_vp0 = _mm_div_ps(_mm_set1_ps(0.25f), _mm_add_ps(v_v0, _mm_mul_ps(v_l0, _mm_set1_ps(vn)))); + __m128 v_vp1 = _mm_div_ps(_mm_set1_ps(0.25f), _mm_add_ps(v_v1, _mm_mul_ps(v_l1, _mm_set1_ps(vn)))); + // vp = max(-0.25, min(0.25, vp)); + v_vp0 = _mm_max_ps(v_vp0, _mm_set1_ps(-0.25f)); + v_vp1 = _mm_max_ps(v_vp1, _mm_set1_ps(-0.25f)); + v_vp0 = _mm_min_ps(v_vp0, _mm_set1_ps( 0.25f)); + v_vp1 = _mm_min_ps(v_vp1, _mm_set1_ps( 0.25f)); + //X = 3*up*vp; // (*Y) is done later + __m128 v_x0 = _mm_mul_ps(_mm_set1_ps(3.f), _mm_mul_ps(v_up0, v_vp0)); + __m128 v_x1 = _mm_mul_ps(_mm_set1_ps(3.f), _mm_mul_ps(v_up1, v_vp1)); + //Z = ((12*13*L - up)*vp - 5); // (*Y) is done later + __m128 v_z0 = _mm_sub_ps(_mm_mul_ps(_mm_sub_ps(_mm_mul_ps(_mm_set1_ps(12.f*13.f), v_l0), v_up0), v_vp0), _mm_set1_ps(5.f)); + __m128 v_z1 = _mm_sub_ps(_mm_mul_ps(_mm_sub_ps(_mm_mul_ps(_mm_set1_ps(12.f*13.f), v_l1), v_up1), v_vp1), _mm_set1_ps(5.f)); + // R = (X*C0 + C1 + Z*C2)*Y; // here (*Y) is done v_l0 = _mm_mul_ps(v_x0, _mm_set1_ps(coeffs[0])); v_l1 = _mm_mul_ps(v_x1, _mm_set1_ps(coeffs[0])); v_u0 = _mm_mul_ps(v_x0, _mm_set1_ps(coeffs[3])); @@ -6902,15 +6921,22 @@ struct Luv2RGB_f #endif for( ; i < n; i += 3, dst += dcn ) { - float L = src[i], u = src[i+1], v = src[i+2], d, X, Y, Z; - Y = (L + 16.f) * (1.f/116.f); - Y = Y*Y*Y; - d = (1.f/13.f)/L; - u = u*d + _un; - v = v*d + _vn; - float iv = 1.f/v; - X = 2.25f * u * Y * iv ; - Z = (12 - 3 * u - 20 * v) * Y * 0.25f * iv; + float L = src[i], u = src[i+1], v = src[i+2], X, Y, Z; + if(L >= 8) + { + Y = (L + 16.f) * (1.f/116.f); + Y = Y*Y*Y; + } + else + { + Y = L * (1.0f/903.3f); // L*(3./29.)^3 + } + float up = 3.f*(u + L*_un); + float vp = 0.25f/(v + L*_vn); + if(vp > 0.25f) vp = 0.25f; + if(vp < -0.25f) vp = -0.25f; + X = Y*3.f*up*vp; + Z = Y*(((12.f*13.f)*L - up)*vp - 5.f); float R = X*C0 + Y*C1 + Z*C2; float G = X*C3 + Y*C4 + Z*C5;