Source code
Revision control
Copy as Markdown
Other Tools
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include <arm_neon.h>
#include "LuminanceNEON.h"
using namespace mozilla::gfx;
/**
* Byte offsets of channels in a native packed gfxColor or cairo image surface.
*/
#ifdef IS_BIG_ENDIAN
# define GFX_ARGB32_OFFSET_A 0
# define GFX_ARGB32_OFFSET_R 1
# define GFX_ARGB32_OFFSET_G 2
# define GFX_ARGB32_OFFSET_B 3
#else
# define GFX_ARGB32_OFFSET_A 3
# define GFX_ARGB32_OFFSET_R 2
# define GFX_ARGB32_OFFSET_G 1
# define GFX_ARGB32_OFFSET_B 0
#endif
void ComputesRGBLuminanceMask_NEON(const uint8_t* aSourceData,
int32_t aSourceStride, uint8_t* aDestData,
int32_t aDestStride, const IntSize& aSize,
float aOpacity) {
int32_t redFactor = 55 * aOpacity; // 255 * 0.2125 * opacity
int32_t greenFactor = 183 * aOpacity; // 255 * 0.7154 * opacity
int32_t blueFactor = 18 * aOpacity; // 255 * 0.0721
const uint8_t* sourcePixel = aSourceData;
int32_t sourceOffset = aSourceStride - 4 * aSize.width;
uint8_t* destPixel = aDestData;
int32_t destOffset = aDestStride - aSize.width;
sourcePixel = aSourceData;
int32_t remainderWidth = aSize.width % 8;
int32_t roundedWidth = aSize.width - remainderWidth;
uint16x8_t temp;
uint8x8_t gray;
uint8x8_t redVector = vdup_n_u8(redFactor);
uint8x8_t greenVector = vdup_n_u8(greenFactor);
uint8x8_t blueVector = vdup_n_u8(blueFactor);
uint8x8_t fullBitVector = vdup_n_u8(255);
uint8x8_t oneVector = vdup_n_u8(1);
for (int32_t y = 0; y < aSize.height; y++) {
// Calculate luminance by neon with 8 pixels per loop
for (int32_t x = 0; x < roundedWidth; x += 8) {
uint8x8x4_t argb = vld4_u8(sourcePixel);
temp = vmull_u8(argb.val[GFX_ARGB32_OFFSET_R],
redVector); // temp = red * redFactor
temp = vmlal_u8(temp, argb.val[GFX_ARGB32_OFFSET_G],
greenVector); // temp += green * greenFactor
temp = vmlal_u8(temp, argb.val[GFX_ARGB32_OFFSET_B],
blueVector); // temp += blue * blueFactor
gray = vshrn_n_u16(temp, 8); // gray = temp >> 8
// Check alpha value
uint8x8_t alphaVector =
vtst_u8(argb.val[GFX_ARGB32_OFFSET_A], fullBitVector);
gray = vmul_u8(gray, vand_u8(alphaVector, oneVector));
// Put the result to the 8 pixels
vst1_u8(destPixel, gray);
sourcePixel += 8 * 4;
destPixel += 8;
}
// Calculate the rest pixels of the line by cpu
for (int32_t x = 0; x < remainderWidth; x++) {
if (sourcePixel[GFX_ARGB32_OFFSET_A] > 0) {
*destPixel = (redFactor * sourcePixel[GFX_ARGB32_OFFSET_R] +
greenFactor * sourcePixel[GFX_ARGB32_OFFSET_G] +
blueFactor * sourcePixel[GFX_ARGB32_OFFSET_B]) >>
8;
} else {
*destPixel = 0;
}
sourcePixel += 4;
destPixel++;
}
sourcePixel += sourceOffset;
destPixel += destOffset;
}
}