Move blur code from FontRenderer to utils/Blur.cpp (6e200408) · Commits · e / os / android_frameworks_base

libs/hwui/Android.mk

+1 −0

Original line number	Diff line number	Diff line
		@@ -5,6 +5,7 @@ include $(CLEAR_VARS)
		# defined in the current device/board configuration
		ifeq ($(USE_OPENGL_RENDERER),true)
		LOCAL_SRC_FILES:= \
		utils/Blur.cpp \
		utils/SortedListImpl.cpp \
		font/CacheTexture.cpp \
		font/Font.cpp \

libs/hwui/FontRenderer.cpp

+8 −132

Original line number	Diff line number	Diff line
		@@ -23,9 +23,11 @@

		#include <utils/Log.h>

		#include "RenderScript.h"
		#include <RenderScript.h>

		#include "utils/Blur.h"
		#include "utils/Timing.h"

		#include "Caches.h"
		#include "Debug.h"
		#include "FontRenderer.h"
		@@ -655,140 +657,14 @@ void FontRenderer::removeFont(const Font* font) {
		}
		}

		void FontRenderer::computeGaussianWeights(float* weights, int32_t radius) {
		// Compute gaussian weights for the blur
		// e is the euler's number
		float e = 2.718281828459045f;
		float pi = 3.1415926535897932f;
		// g(x) = ( 1 / sqrt( 2 * pi ) * sigma) * e ^ ( -x^2 / 2 * sigma^2 )
		// x is of the form [-radius .. 0 .. radius]
		// and sigma varies with radius.
		// Based on some experimental radius values and sigma's
		// we approximately fit sigma = f(radius) as
		// sigma = radius * 0.3 + 0.6
		// The larger the radius gets, the more our gaussian blur
		// will resemble a box blur since with large sigma
		// the gaussian curve begins to lose its shape
		float sigma = 0.3f * (float) radius + 0.6f;

		// Now compute the coefficints
		// We will store some redundant values to save some math during
		// the blur calculations
		// precompute some values
		float coeff1 = 1.0f / (sqrt( 2.0f * pi ) * sigma);
		float coeff2 = - 1.0f / (2.0f * sigma * sigma);

		float normalizeFactor = 0.0f;
		for (int32_t r = -radius; r <= radius; r ++) {
		float floatR = (float) r;
		weights[r + radius] = coeff1 * pow(e, floatR * floatR * coeff2);
		normalizeFactor += weights[r + radius];
		}

		//Now we need to normalize the weights because all our coefficients need to add up to one
		normalizeFactor = 1.0f / normalizeFactor;
		for (int32_t r = -radius; r <= radius; r ++) {
		weights[r + radius] *= normalizeFactor;
		}
		}

		void FontRenderer::horizontalBlur(float* weights, int32_t radius,
		const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) {
		float blurredPixel = 0.0f;
		float currentPixel = 0.0f;

		for (int32_t y = 0; y < height; y ++) {

		const uint8_t* input = source + y * width;
		uint8_t* output = dest + y * width;

		for (int32_t x = 0; x < width; x ++) {
		blurredPixel = 0.0f;
		const float* gPtr = weights;
		// Optimization for non-border pixels
		if (x > radius && x < (width - radius)) {
		const uint8_t *i = input + (x - radius);
		for (int r = -radius; r <= radius; r ++) {
		currentPixel = (float) (*i);
		blurredPixel += currentPixel * gPtr[0];
		gPtr++;
		i++;
		}
		} else {
		for (int32_t r = -radius; r <= radius; r ++) {
		// Stepping left and right away from the pixel
		int validW = x + r;
		if (validW < 0) {
		validW = 0;
		}
		if (validW > width - 1) {
		validW = width - 1;
		}

		currentPixel = (float) input[validW];
		blurredPixel += currentPixel * gPtr[0];
		gPtr++;
		}
		}
		*output = (uint8_t)blurredPixel;
		output ++;
		}
		}
		}

		void FontRenderer::verticalBlur(float* weights, int32_t radius,
		const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) {
		float blurredPixel = 0.0f;
		float currentPixel = 0.0f;

		for (int32_t y = 0; y < height; y ++) {
		uint8_t* output = dest + y * width;

		for (int32_t x = 0; x < width; x ++) {
		blurredPixel = 0.0f;
		const float* gPtr = weights;
		const uint8_t* input = source + x;
		// Optimization for non-border pixels
		if (y > radius && y < (height - radius)) {
		const uint8_t i = input + ((y - radius) width);
		for (int32_t r = -radius; r <= radius; r ++) {
		currentPixel = (float)(*i);
		blurredPixel += currentPixel * gPtr[0];
		gPtr++;
		i += width;
		}
		} else {
		for (int32_t r = -radius; r <= radius; r ++) {
		int validH = y + r;
		// Clamp to zero and width
		if (validH < 0) {
		validH = 0;
		}
		if (validH > height - 1) {
		validH = height - 1;
		}

		const uint8_t i = input + validH width;
		currentPixel = (float) (*i);
		blurredPixel += currentPixel * gPtr[0];
		gPtr++;
		}
		}
		*output = (uint8_t) blurredPixel;
		output++;
		}
		}
		}

		void FontRenderer::blurImage(uint8_t** image, int32_t width, int32_t height, int32_t radius) {
		if (width * height * radius < RS_MIN_INPUT_CUTOFF) {
		float gaussian = new float[2 radius + 1];
		computeGaussianWeights(gaussian, radius);
		Blur::generateGaussianWeights(gaussian, radius);

		uint8_t* scratch = new uint8_t[width * height];

		horizontalBlur(gaussian, radius, *image, scratch, width, height);
		verticalBlur(gaussian, radius, scratch, *image, width, height);
		Blur::horizontal(gaussian, radius, *image, scratch, width, height);
		Blur::vertical(gaussian, radius, scratch, *image, width, height);

		delete[] gaussian;
		delete[] scratch;

libs/hwui/utils/Blur.cpp

0 → 100644

+152 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2013 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		#define LOG_TAG "OpenGLRenderer"

		#include <math.h>

		#include "Blur.h"

		namespace android {
		namespace uirenderer {

		void Blur::generateGaussianWeights(float* weights, int32_t radius) {
		// Compute gaussian weights for the blur
		// e is the euler's number
		static float e = 2.718281828459045f;
		static float pi = 3.1415926535897932f;
		// g(x) = ( 1 / sqrt( 2 * pi ) * sigma) * e ^ ( -x^2 / 2 * sigma^2 )
		// x is of the form [-radius .. 0 .. radius]
		// and sigma varies with radius.
		// Based on some experimental radius values and sigma's
		// we approximately fit sigma = f(radius) as
		// sigma = radius * 0.3 + 0.6
		// The larger the radius gets, the more our gaussian blur
		// will resemble a box blur since with large sigma
		// the gaussian curve begins to lose its shape
		float sigma = 0.3f * (float) radius + 0.6f;

		// Now compute the coefficints
		// We will store some redundant values to save some math during
		// the blur calculations
		// precompute some values
		float coeff1 = 1.0f / (sqrt(2.0f * pi) * sigma);
		float coeff2 = - 1.0f / (2.0f * sigma * sigma);

		float normalizeFactor = 0.0f;
		for (int32_t r = -radius; r <= radius; r ++) {
		float floatR = (float) r;
		weights[r + radius] = coeff1 * pow(e, floatR * floatR * coeff2);
		normalizeFactor += weights[r + radius];
		}

		//Now we need to normalize the weights because all our coefficients need to add up to one
		normalizeFactor = 1.0f / normalizeFactor;
		for (int32_t r = -radius; r <= radius; r ++) {
		weights[r + radius] *= normalizeFactor;
		}
		}

		void Blur::horizontal(float* weights, int32_t radius,
		const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) {
		float blurredPixel = 0.0f;
		float currentPixel = 0.0f;

		for (int32_t y = 0; y < height; y ++) {

		const uint8_t* input = source + y * width;
		uint8_t* output = dest + y * width;

		for (int32_t x = 0; x < width; x ++) {
		blurredPixel = 0.0f;
		const float* gPtr = weights;
		// Optimization for non-border pixels
		if (x > radius && x < (width - radius)) {
		const uint8_t *i = input + (x - radius);
		for (int r = -radius; r <= radius; r ++) {
		currentPixel = (float) (*i);
		blurredPixel += currentPixel * gPtr[0];
		gPtr++;
		i++;
		}
		} else {
		for (int32_t r = -radius; r <= radius; r ++) {
		// Stepping left and right away from the pixel
		int validW = x + r;
		if (validW < 0) {
		validW = 0;
		}
		if (validW > width - 1) {
		validW = width - 1;
		}

		currentPixel = (float) input[validW];
		blurredPixel += currentPixel * gPtr[0];
		gPtr++;
		}
		}
		*output = (uint8_t)blurredPixel;
		output ++;
		}
		}
		}

		void Blur::vertical(float* weights, int32_t radius,
		const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) {
		float blurredPixel = 0.0f;
		float currentPixel = 0.0f;

		for (int32_t y = 0; y < height; y ++) {
		uint8_t* output = dest + y * width;

		for (int32_t x = 0; x < width; x ++) {
		blurredPixel = 0.0f;
		const float* gPtr = weights;
		const uint8_t* input = source + x;
		// Optimization for non-border pixels
		if (y > radius && y < (height - radius)) {
		const uint8_t i = input + ((y - radius) width);
		for (int32_t r = -radius; r <= radius; r ++) {
		currentPixel = (float) (*i);
		blurredPixel += currentPixel * gPtr[0];
		gPtr++;
		i += width;
		}
		} else {
		for (int32_t r = -radius; r <= radius; r ++) {
		int validH = y + r;
		// Clamp to zero and width
		if (validH < 0) {
		validH = 0;
		}
		if (validH > height - 1) {
		validH = height - 1;
		}

		const uint8_t i = input + validH width;
		currentPixel = (float) (*i);
		blurredPixel += currentPixel * gPtr[0];
		gPtr++;
		}
		}
		*output = (uint8_t) blurredPixel;
		output++;
		}
		}
		}

		}; // namespace uirenderer
		}; // namespace android

libs/hwui/utils/Blur.h

0 → 100644

+37 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2013 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		#ifndef ANDROID_HWUI_BLUR_H
		#define ANDROID_HWUI_BLUR_H

		#include <stdint.h>

		namespace android {
		namespace uirenderer {

		class Blur {
		public:
		static void generateGaussianWeights(float* weights, int32_t radius);
		static void horizontal(float* weights, int32_t radius, const uint8_t* source,
		uint8_t* dest, int32_t width, int32_t height);
		static void vertical(float* weights, int32_t radius, const uint8_t* source,
		uint8_t* dest, int32_t width, int32_t height);
		};

		}; // namespace uirenderer
		}; // namespace android

		#endif // ANDROID_HWUI_BLUR_H