1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7 #include <arm_neon.h>
8 #include "LuminanceNEON.h"
9
10 using namespace mozilla::gfx;
11
12 /**
13 * Byte offsets of channels in a native packed gfxColor or cairo image surface.
14 */
15 #ifdef IS_BIG_ENDIAN
16 # define GFX_ARGB32_OFFSET_A 0
17 # define GFX_ARGB32_OFFSET_R 1
18 # define GFX_ARGB32_OFFSET_G 2
19 # define GFX_ARGB32_OFFSET_B 3
20 #else
21 # define GFX_ARGB32_OFFSET_A 3
22 # define GFX_ARGB32_OFFSET_R 2
23 # define GFX_ARGB32_OFFSET_G 1
24 # define GFX_ARGB32_OFFSET_B 0
25 #endif
26
ComputesRGBLuminanceMask_NEON(const uint8_t * aSourceData,int32_t aSourceStride,uint8_t * aDestData,int32_t aDestStride,const IntSize & aSize,float aOpacity)27 void ComputesRGBLuminanceMask_NEON(const uint8_t* aSourceData,
28 int32_t aSourceStride, uint8_t* aDestData,
29 int32_t aDestStride, const IntSize& aSize,
30 float aOpacity) {
31 int32_t redFactor = 55 * aOpacity; // 255 * 0.2125 * opacity
32 int32_t greenFactor = 183 * aOpacity; // 255 * 0.7154 * opacity
33 int32_t blueFactor = 18 * aOpacity; // 255 * 0.0721
34 const uint8_t* sourcePixel = aSourceData;
35 int32_t sourceOffset = aSourceStride - 4 * aSize.width;
36 uint8_t* destPixel = aDestData;
37 int32_t destOffset = aDestStride - aSize.width;
38
39 sourcePixel = aSourceData;
40 int32_t remainderWidth = aSize.width % 8;
41 int32_t roundedWidth = aSize.width - remainderWidth;
42 uint16x8_t temp;
43 uint8x8_t gray;
44 uint8x8_t redVector = vdup_n_u8(redFactor);
45 uint8x8_t greenVector = vdup_n_u8(greenFactor);
46 uint8x8_t blueVector = vdup_n_u8(blueFactor);
47 uint8x8_t fullBitVector = vdup_n_u8(255);
48 uint8x8_t oneVector = vdup_n_u8(1);
49 for (int32_t y = 0; y < aSize.height; y++) {
50 // Calculate luminance by neon with 8 pixels per loop
51 for (int32_t x = 0; x < roundedWidth; x += 8) {
52 uint8x8x4_t argb = vld4_u8(sourcePixel);
53 temp = vmull_u8(argb.val[GFX_ARGB32_OFFSET_R],
54 redVector); // temp = red * redFactor
55 temp = vmlal_u8(temp, argb.val[GFX_ARGB32_OFFSET_G],
56 greenVector); // temp += green * greenFactor
57 temp = vmlal_u8(temp, argb.val[GFX_ARGB32_OFFSET_B],
58 blueVector); // temp += blue * blueFactor
59 gray = vshrn_n_u16(temp, 8); // gray = temp >> 8
60
61 // Check alpha value
62 uint8x8_t alphaVector =
63 vtst_u8(argb.val[GFX_ARGB32_OFFSET_A], fullBitVector);
64 gray = vmul_u8(gray, vand_u8(alphaVector, oneVector));
65
66 // Put the result to the 8 pixels
67 vst1_u8(destPixel, gray);
68 sourcePixel += 8 * 4;
69 destPixel += 8;
70 }
71
72 // Calculate the rest pixels of the line by cpu
73 for (int32_t x = 0; x < remainderWidth; x++) {
74 if (sourcePixel[GFX_ARGB32_OFFSET_A] > 0) {
75 *destPixel = (redFactor * sourcePixel[GFX_ARGB32_OFFSET_R] +
76 greenFactor * sourcePixel[GFX_ARGB32_OFFSET_G] +
77 blueFactor * sourcePixel[GFX_ARGB32_OFFSET_B]) >>
78 8;
79 } else {
80 *destPixel = 0;
81 }
82 sourcePixel += 4;
83 destPixel++;
84 }
85 sourcePixel += sourceOffset;
86 destPixel += destOffset;
87 }
88 }
89