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Merge branch 'simd/alpha-composite' into simd/5.3.x

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Alexander 2018-10-17 14:51:45 +03:00
commit 0fc8680360
1 changed files with 167 additions and 15 deletions
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182
src/libImaging/AlphaComposite.c
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@ -11,6 +11,14 @@
#include "Imaging.h"
#include <emmintrin.h>
#include <mmintrin.h>
#include <smmintrin.h>
#if defined(__AVX2__)
#include <immintrin.h>
#endif
#define PRECISION_BITS 7
typedef struct
@ -28,6 +36,28 @@ ImagingAlphaComposite(Imaging imDst, Imaging imSrc)
{
Imaging imOut;
int x, y;
int xsize = imDst->xsize;
__m128i mm_max_alpha = _mm_set1_epi32(255);
__m128i mm_max_alpha2 = _mm_set1_epi32(255 * 255);
__m128i mm_zero = _mm_setzero_si128();
__m128i mm_half = _mm_set1_epi16(128);
__m128i mm_get_lo = _mm_set_epi8(
-1,-1, 5,4, 5,4, 5,4, -1,-1, 1,0, 1,0, 1,0);
__m128i mm_get_hi = _mm_set_epi8(
-1,-1, 13,12, 13,12, 13,12, -1,-1, 9,8, 9,8, 9,8);
#if defined(__AVX2__)
__m256i vmm_max_alpha = _mm256_set1_epi32(255);
__m256i vmm_max_alpha2 = _mm256_set1_epi32(255 * 255);
__m256i vmm_zero = _mm256_setzero_si256();
__m256i vmm_half = _mm256_set1_epi16(128);
__m256i vmm_get_lo = _mm256_set_epi8(
-1,-1, 5,4, 5,4, 5,4, -1,-1, 1,0, 1,0, 1,0,
-1,-1, 5,4, 5,4, 5,4, -1,-1, 1,0, 1,0, 1,0);
__m256i vmm_get_hi = _mm256_set_epi8(
-1,-1, 13,12, 13,12, 13,12, -1,-1, 9,8, 9,8, 9,8,
-1,-1, 13,12, 13,12, 13,12, -1,-1, 9,8, 9,8, 9,8);
#endif
/* Check arguments */
if (!imDst || !imSrc ||
@ -52,33 +82,155 @@ ImagingAlphaComposite(Imaging imDst, Imaging imSrc)
rgba8* src = (rgba8*) imSrc->image[y];
rgba8* out = (rgba8*) imOut->image[y];
for (x = 0; x < imDst->xsize; x ++) {
if (src->a == 0) {
x = 0;
#if defined(__AVX2__)
#define MM_SHIFTDIV255_epi16(src)\
_mm256_srli_epi16(_mm256_add_epi16(src, _mm256_srli_epi16(src, 8)), 8)
for (; x < xsize - 7; x += 8) {
__m256i mm_dst, mm_dst_lo, mm_dst_hi;
__m256i mm_src, mm_src_lo, mm_src_hi;
__m256i mm_dst_a, mm_src_a, mm_out_a, mm_blend;
__m256i mm_coef1, mm_coef2, mm_out_lo, mm_out_hi;
mm_dst = _mm256_loadu_si256((__m256i *) &dst[x]);
mm_dst_lo = _mm256_unpacklo_epi8(mm_dst, vmm_zero);
mm_dst_hi = _mm256_unpackhi_epi8(mm_dst, vmm_zero);
mm_src = _mm256_loadu_si256((__m256i *) &src[x]);
mm_src_lo = _mm256_unpacklo_epi8(mm_src, vmm_zero);
mm_src_hi = _mm256_unpackhi_epi8(mm_src, vmm_zero);
mm_dst_a = _mm256_srli_epi32(mm_dst, 24);
mm_src_a = _mm256_srli_epi32(mm_src, 24);
// Compute coefficients
// blend = dst->a * (255 - src->a); 16 bits
mm_blend = _mm256_mullo_epi16(mm_dst_a, _mm256_sub_epi32(vmm_max_alpha, mm_src_a));
// outa = src->a * 255 + dst->a * (255 - src->a); 16 bits
mm_out_a = _mm256_add_epi32(_mm256_mullo_epi16(mm_src_a, vmm_max_alpha), mm_blend);
mm_coef1 = _mm256_mullo_epi32(mm_src_a, vmm_max_alpha2);
// 8 bits
mm_coef1 = _mm256_cvtps_epi32(
_mm256_mul_ps(_mm256_cvtepi32_ps(mm_coef1),
_mm256_rcp_ps(_mm256_cvtepi32_ps(mm_out_a)))
);
// 8 bits
mm_coef2 = _mm256_sub_epi32(vmm_max_alpha, mm_coef1);
mm_out_lo = _mm256_add_epi16(
_mm256_mullo_epi16(mm_src_lo, _mm256_shuffle_epi8(mm_coef1, vmm_get_lo)),
_mm256_mullo_epi16(mm_dst_lo, _mm256_shuffle_epi8(mm_coef2, vmm_get_lo)));
mm_out_lo = _mm256_or_si256(mm_out_lo, _mm256_slli_epi64(
_mm256_unpacklo_epi32(mm_out_a, vmm_zero), 48));
mm_out_lo = _mm256_add_epi16(mm_out_lo, vmm_half);
mm_out_lo = MM_SHIFTDIV255_epi16(mm_out_lo);
mm_out_hi = _mm256_add_epi16(
_mm256_mullo_epi16(mm_src_hi, _mm256_shuffle_epi8(mm_coef1, vmm_get_hi)),
_mm256_mullo_epi16(mm_dst_hi, _mm256_shuffle_epi8(mm_coef2, vmm_get_hi)));
mm_out_hi = _mm256_or_si256(mm_out_hi, _mm256_slli_epi64(
_mm256_unpackhi_epi32(mm_out_a, vmm_zero), 48));
mm_out_hi = _mm256_add_epi16(mm_out_hi, vmm_half);
mm_out_hi = MM_SHIFTDIV255_epi16(mm_out_hi);
_mm256_storeu_si256((__m256i *) &out[x],
_mm256_packus_epi16(mm_out_lo, mm_out_hi));
}
#undef MM_SHIFTDIV255_epi16
#endif
#define MM_SHIFTDIV255_epi16(src)\
_mm_srli_epi16(_mm_add_epi16(src, _mm_srli_epi16(src, 8)), 8)
for (; x < xsize - 3; x += 4) {
__m128i mm_dst, mm_dst_lo, mm_dst_hi;
__m128i mm_src, mm_src_hi, mm_src_lo;
__m128i mm_dst_a, mm_src_a, mm_out_a, mm_blend;
__m128i mm_coef1, mm_coef2, mm_out_lo, mm_out_hi;
// [8] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
mm_dst = _mm_loadu_si128((__m128i *) &dst[x]);
// [16] a1 b1 g1 r1 a0 b0 g0 r0
mm_dst_lo = _mm_unpacklo_epi8(mm_dst, mm_zero);
// [16] a3 b3 g3 r3 a2 b2 g2 r2
mm_dst_hi = _mm_unpackhi_epi8(mm_dst, mm_zero);
// [8] a3 b3 g3 r3 a2 b2 g2 r2 a1 b1 g1 r1 a0 b0 g0 r0
mm_src = _mm_loadu_si128((__m128i *) &src[x]);
mm_src_lo = _mm_unpacklo_epi8(mm_src, mm_zero);
mm_src_hi = _mm_unpackhi_epi8(mm_src, mm_zero);
// [32] a3 a2 a1 a0
mm_dst_a = _mm_srli_epi32(mm_dst, 24);
mm_src_a = _mm_srli_epi32(mm_src, 24);
// Compute coefficients
// blend = dst->a * (255 - src->a)
// [16] xx b3 xx b2 xx b1 xx b0
mm_blend = _mm_mullo_epi16(mm_dst_a, _mm_sub_epi32(mm_max_alpha, mm_src_a));
// outa = src->a * 255 + blend
// [16] xx a3 xx a2 xx a1 xx a0
mm_out_a = _mm_add_epi32(_mm_mullo_epi16(mm_src_a, mm_max_alpha), mm_blend);
// coef1 = src->a * 255 * 255 / outa
mm_coef1 = _mm_mullo_epi32(mm_src_a, mm_max_alpha2);
// [8] xx xx xx c3 xx xx xx c2 xx xx xx c1 xx xx xx c0
mm_coef1 = _mm_cvtps_epi32(
_mm_mul_ps(_mm_cvtepi32_ps(mm_coef1),
_mm_rcp_ps(_mm_cvtepi32_ps(mm_out_a)))
);
// [8] xx xx xx c3 xx xx xx c2 xx xx xx c1 xx xx xx c0
mm_coef2 = _mm_sub_epi32(mm_max_alpha, mm_coef1);
mm_out_lo = _mm_add_epi16(
_mm_mullo_epi16(mm_src_lo, _mm_shuffle_epi8(mm_coef1, mm_get_lo)),
_mm_mullo_epi16(mm_dst_lo, _mm_shuffle_epi8(mm_coef2, mm_get_lo)));
mm_out_lo = _mm_or_si128(mm_out_lo, _mm_slli_epi64(
_mm_unpacklo_epi32(mm_out_a, mm_zero), 48));
mm_out_lo = _mm_add_epi16(mm_out_lo, mm_half);
mm_out_lo = MM_SHIFTDIV255_epi16(mm_out_lo);
mm_out_hi = _mm_add_epi16(
_mm_mullo_epi16(mm_src_hi, _mm_shuffle_epi8(mm_coef1, mm_get_hi)),
_mm_mullo_epi16(mm_dst_hi, _mm_shuffle_epi8(mm_coef2, mm_get_hi)));
mm_out_hi = _mm_or_si128(mm_out_hi, _mm_slli_epi64(
_mm_unpackhi_epi32(mm_out_a, mm_zero), 48));
mm_out_hi = _mm_add_epi16(mm_out_hi, mm_half);
mm_out_hi = MM_SHIFTDIV255_epi16(mm_out_hi);
_mm_storeu_si128((__m128i *) &out[x],
_mm_packus_epi16(mm_out_lo, mm_out_hi));
}
#undef MM_SHIFTDIV255_epi16
for (; x < xsize; x += 1) {
if (src[x].a == 0) {
// Copy 4 bytes at once.
*out = *dst;
out[x] = dst[x];
} else {
// Integer implementation with increased precision.
// Each variable has extra meaningful bits.
// Divisions are rounded.
UINT32 tmpr, tmpg, tmpb;
UINT32 blend = dst->a * (255 - src->a);
UINT32 outa255 = src->a * 255 + blend;
UINT32 blend = dst[x].a * (255 - src[x].a);
UINT32 outa255 = src[x].a * 255 + blend;
// There we use 7 bits for precision.
// We could use more, but we go beyond 32 bits.
UINT32 coef1 = src->a * 255 * 255 * (1<<PRECISION_BITS) / outa255;
UINT32 coef1 = src[x].a * 255 * 255 * (1<<PRECISION_BITS) / outa255;
UINT32 coef2 = 255 * (1<<PRECISION_BITS) - coef1;
tmpr = src->r * coef1 + dst->r * coef2;
tmpg = src->g * coef1 + dst->g * coef2;
tmpb = src->b * coef1 + dst->b * coef2;
out->r = SHIFTFORDIV255(tmpr + (0x80<<PRECISION_BITS)) >> PRECISION_BITS;
out->g = SHIFTFORDIV255(tmpg + (0x80<<PRECISION_BITS)) >> PRECISION_BITS;
out->b = SHIFTFORDIV255(tmpb + (0x80<<PRECISION_BITS)) >> PRECISION_BITS;
out->a = SHIFTFORDIV255(outa255 + 0x80);
tmpr = src[x].r * coef1 + dst[x].r * coef2;
tmpg = src[x].g * coef1 + dst[x].g * coef2;
tmpb = src[x].b * coef1 + dst[x].b * coef2;
out[x].r = SHIFTFORDIV255(tmpr + (0x80<<PRECISION_BITS)) >> PRECISION_BITS;
out[x].g = SHIFTFORDIV255(tmpg + (0x80<<PRECISION_BITS)) >> PRECISION_BITS;
out[x].b = SHIFTFORDIV255(tmpb + (0x80<<PRECISION_BITS)) >> PRECISION_BITS;
out[x].a = SHIFTFORDIV255(outa255 + 0x80);
}
dst++; src++; out++;
}
}