1 /* 2 * vim:ts=4:sw=4:expandtab 3 * 4 * © 2016 Sebastian Frysztak 5 * 6 * See LICENSE for licensing information 7 * 8 */ 9 10 11 // number of xmm registers needed to store input pixels for given kernel size 12 #ifdef __SSE2__ 13 #include "blur.h" 14 #define REGISTERS_CNT (KERNEL_SIZE + 4/2) / 4 15 #include <xmmintrin.h> 16 void blur_impl_horizontal_pass_sse2(uint32_t *src, uint32_t *dst, int width, int height) { 17 uint32_t* o_src = src; 18 for (int row = 0; row < height; row++) { 19 for (int column = 0; column < width; column++, src++) { 20 __m128i rgbaIn[REGISTERS_CNT]; 21 22 // handle borders 23 int leftBorder = column < HALF_KERNEL; 24 int rightBorder = column > width - HALF_KERNEL; 25 uint32_t _rgbaIn[KERNEL_SIZE + 1] __attribute__((aligned(16))); 26 int i = 0; 27 if (leftBorder) { 28 // for kernel size 7x7 and column == 0, we have: 29 // x x x P0 P1 P2 P3 30 // first loop mirrors P{0..3} to fill x's, 31 // second one loads P{0..3} 32 for (; i < HALF_KERNEL - column; i++) 33 _rgbaIn[i] = *(src + (HALF_KERNEL - i)); 34 for (; i < KERNEL_SIZE; i++) 35 _rgbaIn[i] = *(src - (HALF_KERNEL - i)); 36 37 for (int k = 0; k < REGISTERS_CNT; k++) 38 rgbaIn[k] = _mm_load_si128((__m128i*)(_rgbaIn + 4*k)); 39 } else if (rightBorder) { 40 for (; i < width - column; i++) 41 _rgbaIn[i] = *(src + i); 42 for (int k = 0; i < KERNEL_SIZE; i++, k++) 43 _rgbaIn[i] = *(src - k); 44 45 for (int k = 0; k < REGISTERS_CNT; k++) 46 rgbaIn[k] = _mm_load_si128((__m128i*)(_rgbaIn + 4*k)); 47 } else { 48 for (int k = 0; k < REGISTERS_CNT; k++) { 49 if ((uintptr_t) (((__m128i*) src + 4*k - HALF_KERNEL) + 1) 50 > (uintptr_t) (o_src + (height * width))) 51 break; 52 rgbaIn[k] = _mm_loadu_si128((__m128i*)(src + 4*k - HALF_KERNEL)); 53 } 54 } 55 56 __m128i zero = _mm_setzero_si128(); 57 __m128i acc = _mm_setzero_si128(); 58 59 acc = _mm_add_epi16(acc, _mm_unpacklo_epi8(rgbaIn[0], zero)); 60 acc = _mm_add_epi16(acc, _mm_unpackhi_epi8(rgbaIn[0], zero)); 61 acc = _mm_add_epi16(acc, _mm_unpacklo_epi8(rgbaIn[1], zero)); 62 63 // kernel size equals to 7, but we can only load multiples of 4 pixels 64 // we have to set 8th pixel to zero 65 acc = _mm_add_epi16(acc, _mm_andnot_si128(_mm_set_epi32(0xFFFFFFFF, 0xFFFFFFFF, 0, 0), 66 _mm_unpackhi_epi8(rgbaIn[1], zero))); 67 acc = _mm_add_epi32(_mm_unpacklo_epi16(acc, zero), 68 _mm_unpackhi_epi16(acc, zero)); 69 70 // multiplication is significantly faster than division 71 acc = _mm_cvtps_epi32(_mm_mul_ps(_mm_cvtepi32_ps(acc), 72 _mm_set1_ps(1.0/KERNEL_SIZE))); 73 74 *(dst + height * column + row) = 75 _mm_cvtsi128_si32(_mm_packus_epi16(_mm_packs_epi32(acc, zero), zero)); 76 } 77 } 78 } 79 #endif
