summaryrefslogtreecommitdiff
path: root/toolkit/Blur.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'toolkit/Blur.cpp')
-rw-r--r--toolkit/Blur.cpp545
1 files changed, 545 insertions, 0 deletions
diff --git a/toolkit/Blur.cpp b/toolkit/Blur.cpp
new file mode 100644
index 00000000..a95ff435
--- /dev/null
+++ b/toolkit/Blur.cpp
@@ -0,0 +1,545 @@
+/*
+ * Copyright (C) 2012 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.
+ */
+
+#include <math.h>
+
+#include <cstdint>
+
+#include "RenderScriptToolkit.h"
+#include "TaskProcessor.h"
+#include "Utils.h"
+
+namespace android {
+namespace renderscript {
+
+#define LOG_TAG "renderscript.toolkit.Blur"
+
+/**
+ * Blurs an image or a section of an image.
+ *
+ * Our algorithm does two passes: a vertical blur followed by an horizontal blur.
+ */
+class BlurTask : public Task {
+ // The image we're blurring.
+ const uchar* mIn;
+ // Where we store the blurred image.
+ uchar* outArray;
+ // The size of the kernel radius is limited to 25 in ScriptIntrinsicBlur.java.
+ // So, the max kernel size is 51 (= 2 * 25 + 1).
+ // Considering SSSE3 case, which requires the size is multiple of 4,
+ // at least 52 words are necessary. Values outside of the kernel should be 0.
+ float mFp[104];
+ uint16_t mIp[104];
+
+ // Working area to store the result of the vertical blur, to be used by the horizontal pass.
+ // There's one area per thread. Since the needed working area may be too large to put on the
+ // stack, we are allocating it from the heap. To avoid paying the allocation cost for each
+ // tile, we cache the scratch area here.
+ std::vector<void*> mScratch; // Pointers to the scratch areas, one per thread.
+ std::vector<size_t> mScratchSize; // The size in bytes of the scratch areas, one per thread.
+
+ // The radius of the blur, in floating point and integer format.
+ float mRadius;
+ int mIradius;
+
+ void kernelU4(void* outPtr, uint32_t xstart, uint32_t xend, uint32_t currentY,
+ uint32_t threadIndex);
+ void kernelU1(void* outPtr, uint32_t xstart, uint32_t xend, uint32_t currentY);
+ void ComputeGaussianWeights();
+
+ // Process a 2D tile of the overall work. threadIndex identifies which thread does the work.
+ virtual void processData(int threadIndex, size_t startX, size_t startY, size_t endX,
+ size_t endY) override;
+
+ public:
+ BlurTask(const uint8_t* in, uint8_t* out, size_t sizeX, size_t sizeY, size_t vectorSize,
+ uint32_t threadCount, float radius, const Restriction* restriction)
+ : Task{sizeX, sizeY, vectorSize, false, restriction},
+ mIn{in},
+ outArray{out},
+ mScratch{threadCount},
+ mScratchSize{threadCount},
+ mRadius{std::min(25.0f, radius)} {
+ ComputeGaussianWeights();
+ }
+
+ ~BlurTask() {
+ for (size_t i = 0; i < mScratch.size(); i++) {
+ if (mScratch[i]) {
+ free(mScratch[i]);
+ }
+ }
+ }
+};
+
+void BlurTask::ComputeGaussianWeights() {
+ memset(mFp, 0, sizeof(mFp));
+ memset(mIp, 0, sizeof(mIp));
+
+ // 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 the radius.
+ // Based on some experimental radius values and sigmas,
+ // we approximately fit sigma = f(radius) as
+ // sigma = radius * 0.4 + 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 = 0.4f * mRadius + 0.6f;
+
+ // Now compute the coefficients. We will store some redundant values to save
+ // some math during the blur calculations precompute some values
+ float coeff1 = 1.0f / (sqrtf(2.0f * pi) * sigma);
+ float coeff2 = - 1.0f / (2.0f * sigma * sigma);
+
+ float normalizeFactor = 0.0f;
+ float floatR = 0.0f;
+ int r;
+ mIradius = (float)ceil(mRadius) + 0.5f;
+ for (r = -mIradius; r <= mIradius; r ++) {
+ floatR = (float)r;
+ mFp[r + mIradius] = coeff1 * powf(e, floatR * floatR * coeff2);
+ normalizeFactor += mFp[r + mIradius];
+ }
+
+ // Now we need to normalize the weights because all our coefficients need to add up to one
+ normalizeFactor = 1.0f / normalizeFactor;
+ for (r = -mIradius; r <= mIradius; r ++) {
+ mFp[r + mIradius] *= normalizeFactor;
+ mIp[r + mIradius] = (uint16_t)(mFp[r + mIradius] * 65536.0f + 0.5f);
+ }
+}
+
+/**
+ * Vertical blur of a uchar4 line.
+ *
+ * @param sizeY Number of cells of the input array in the vertical direction.
+ * @param out Where to place the computed value.
+ * @param x Coordinate of the point we're blurring.
+ * @param y Coordinate of the point we're blurring.
+ * @param ptrIn Start of the input array.
+ * @param iStride The size in byte of a row of the input array.
+ * @param gPtr The gaussian coefficients.
+ * @param iradius The radius of the blur.
+ */
+static void OneVU4(uint32_t sizeY, float4* out, int32_t x, int32_t y, const uchar* ptrIn,
+ int iStride, const float* gPtr, int iradius) {
+ const uchar *pi = ptrIn + x*4;
+
+ float4 blurredPixel = 0;
+ for (int r = -iradius; r <= iradius; r ++) {
+ int validY = std::max((y + r), 0);
+ validY = std::min(validY, (int)(sizeY - 1));
+ const uchar4 *pvy = (const uchar4 *)&pi[validY * iStride];
+ float4 pf = convert<float4>(pvy[0]);
+ blurredPixel += pf * gPtr[0];
+ gPtr++;
+ }
+
+ out[0] = blurredPixel;
+}
+
+/**
+ * Vertical blur of a uchar1 line.
+ *
+ * @param sizeY Number of cells of the input array in the vertical direction.
+ * @param out Where to place the computed value.
+ * @param x Coordinate of the point we're blurring.
+ * @param y Coordinate of the point we're blurring.
+ * @param ptrIn Start of the input array.
+ * @param iStride The size in byte of a row of the input array.
+ * @param gPtr The gaussian coefficients.
+ * @param iradius The radius of the blur.
+ */
+static void OneVU1(uint32_t sizeY, float *out, int32_t x, int32_t y,
+ const uchar *ptrIn, int iStride, const float* gPtr, int iradius) {
+
+ const uchar *pi = ptrIn + x;
+
+ float blurredPixel = 0;
+ for (int r = -iradius; r <= iradius; r ++) {
+ int validY = std::max((y + r), 0);
+ validY = std::min(validY, (int)(sizeY - 1));
+ float pf = (float)pi[validY * iStride];
+ blurredPixel += pf * gPtr[0];
+ gPtr++;
+ }
+
+ out[0] = blurredPixel;
+}
+
+
+extern "C" void rsdIntrinsicBlurU1_K(uchar *out, uchar const *in, size_t w, size_t h,
+ size_t p, size_t x, size_t y, size_t count, size_t r, uint16_t const *tab);
+extern "C" void rsdIntrinsicBlurU4_K(uchar4 *out, uchar4 const *in, size_t w, size_t h,
+ size_t p, size_t x, size_t y, size_t count, size_t r, uint16_t const *tab);
+
+#if defined(ARCH_X86_HAVE_SSSE3)
+extern void rsdIntrinsicBlurVFU4_K(void *dst, const void *pin, int stride, const void *gptr,
+ int rct, int x1, int ct);
+extern void rsdIntrinsicBlurHFU4_K(void *dst, const void *pin, const void *gptr, int rct, int x1,
+ int ct);
+extern void rsdIntrinsicBlurHFU1_K(void *dst, const void *pin, const void *gptr, int rct, int x1,
+ int ct);
+#endif
+
+/**
+ * Vertical blur of a line of RGBA, knowing that there's enough rows above and below us to avoid
+ * dealing with boundary conditions.
+ *
+ * @param out Where to store the results. This is the input to the horizontal blur.
+ * @param ptrIn The input data for this line.
+ * @param iStride The width of the input.
+ * @param gPtr The gaussian coefficients.
+ * @param ct The diameter of the blur.
+ * @param len How many cells to blur.
+ * @param usesSimd Whether this processor supports SIMD.
+ */
+static void OneVFU4(float4 *out, const uchar *ptrIn, int iStride, const float* gPtr, int ct,
+ int x2, bool usesSimd) {
+ int x1 = 0;
+#if defined(ARCH_X86_HAVE_SSSE3)
+ if (usesSimd) {
+ int t = (x2 - x1);
+ t &= ~1;
+ if (t) {
+ rsdIntrinsicBlurVFU4_K(out, ptrIn, iStride, gPtr, ct, x1, x1 + t);
+ }
+ x1 += t;
+ out += t;
+ ptrIn += t << 2;
+ }
+#else
+ (void) usesSimd; // Avoid unused parameter warning.
+#endif
+ while(x2 > x1) {
+ const uchar *pi = ptrIn;
+ float4 blurredPixel = 0;
+ const float* gp = gPtr;
+
+ for (int r = 0; r < ct; r++) {
+ float4 pf = convert<float4>(((const uchar4 *)pi)[0]);
+ blurredPixel += pf * gp[0];
+ pi += iStride;
+ gp++;
+ }
+ out->xyzw = blurredPixel;
+ x1++;
+ out++;
+ ptrIn+=4;
+ }
+}
+
+/**
+ * Vertical blur of a line of U_8, knowing that there's enough rows above and below us to avoid
+ * dealing with boundary conditions.
+ *
+ * @param out Where to store the results. This is the input to the horizontal blur.
+ * @param ptrIn The input data for this line.
+ * @param iStride The width of the input.
+ * @param gPtr The gaussian coefficients.
+ * @param ct The diameter of the blur.
+ * @param len How many cells to blur.
+ * @param usesSimd Whether this processor supports SIMD.
+ */
+static void OneVFU1(float* out, const uchar* ptrIn, int iStride, const float* gPtr, int ct, int len,
+ bool usesSimd) {
+ int x1 = 0;
+
+ while((len > x1) && (((uintptr_t)ptrIn) & 0x3)) {
+ const uchar *pi = ptrIn;
+ float blurredPixel = 0;
+ const float* gp = gPtr;
+
+ for (int r = 0; r < ct; r++) {
+ float pf = (float)pi[0];
+ blurredPixel += pf * gp[0];
+ pi += iStride;
+ gp++;
+ }
+ out[0] = blurredPixel;
+ x1++;
+ out++;
+ ptrIn++;
+ len--;
+ }
+#if defined(ARCH_X86_HAVE_SSSE3)
+ if (usesSimd && (len > x1)) {
+ int t = (len - x1) >> 2;
+ t &= ~1;
+ if (t) {
+ rsdIntrinsicBlurVFU4_K(out, ptrIn, iStride, gPtr, ct, 0, t );
+ len -= t << 2;
+ ptrIn += t << 2;
+ out += t << 2;
+ }
+ }
+#else
+ (void) usesSimd; // Avoid unused parameter warning.
+#endif
+ while(len > 0) {
+ const uchar *pi = ptrIn;
+ float blurredPixel = 0;
+ const float* gp = gPtr;
+
+ for (int r = 0; r < ct; r++) {
+ float pf = (float)pi[0];
+ blurredPixel += pf * gp[0];
+ pi += iStride;
+ gp++;
+ }
+ out[0] = blurredPixel;
+ len--;
+ out++;
+ ptrIn++;
+ }
+}
+
+/**
+ * Horizontal blur of a uchar4 line.
+ *
+ * @param sizeX Number of cells of the input array in the horizontal direction.
+ * @param out Where to place the computed value.
+ * @param x Coordinate of the point we're blurring.
+ * @param ptrIn The start of the input row from which we're indexing x.
+ * @param gPtr The gaussian coefficients.
+ * @param iradius The radius of the blur.
+ */
+static void OneHU4(uint32_t sizeX, uchar4* out, int32_t x, const float4* ptrIn, const float* gPtr,
+ int iradius) {
+ float4 blurredPixel = 0;
+ for (int r = -iradius; r <= iradius; r ++) {
+ int validX = std::max((x + r), 0);
+ validX = std::min(validX, (int)(sizeX - 1));
+ float4 pf = ptrIn[validX];
+ blurredPixel += pf * gPtr[0];
+ gPtr++;
+ }
+
+ out->xyzw = convert<uchar4>(blurredPixel);
+}
+
+/**
+ * Horizontal blur of a uchar line.
+ *
+ * @param sizeX Number of cells of the input array in the horizontal direction.
+ * @param out Where to place the computed value.
+ * @param x Coordinate of the point we're blurring.
+ * @param ptrIn The start of the input row from which we're indexing x.
+ * @param gPtr The gaussian coefficients.
+ * @param iradius The radius of the blur.
+ */
+static void OneHU1(uint32_t sizeX, uchar* out, int32_t x, const float* ptrIn, const float* gPtr,
+ int iradius) {
+ float blurredPixel = 0;
+ for (int r = -iradius; r <= iradius; r ++) {
+ int validX = std::max((x + r), 0);
+ validX = std::min(validX, (int)(sizeX - 1));
+ float pf = ptrIn[validX];
+ blurredPixel += pf * gPtr[0];
+ gPtr++;
+ }
+
+ out[0] = (uchar)blurredPixel;
+}
+
+/**
+ * Full blur of a line of RGBA data.
+ *
+ * @param outPtr Where to store the results
+ * @param xstart The index of the section we're starting to blur.
+ * @param xend The end index of the section.
+ * @param currentY The index of the line we're blurring.
+ * @param usesSimd Whether this processor supports SIMD.
+ */
+void BlurTask::kernelU4(void *outPtr, uint32_t xstart, uint32_t xend, uint32_t currentY,
+ uint32_t threadIndex) {
+ float4 stackbuf[2048];
+ float4 *buf = &stackbuf[0];
+ const uint32_t stride = mSizeX * mVectorSize;
+
+ uchar4 *out = (uchar4 *)outPtr;
+ uint32_t x1 = xstart;
+ uint32_t x2 = xend;
+
+#if defined(ARCH_ARM_USE_INTRINSICS)
+ if (mUsesSimd && mSizeX >= 4) {
+ rsdIntrinsicBlurU4_K(out, (uchar4 const *)(mIn + stride * currentY),
+ mSizeX, mSizeY,
+ stride, x1, currentY, x2 - x1, mIradius, mIp + mIradius);
+ return;
+ }
+#endif
+
+ if (mSizeX > 2048) {
+ if ((mSizeX > mScratchSize[threadIndex]) || !mScratch[threadIndex]) {
+ // Pad the side of the allocation by one unit to allow alignment later
+ mScratch[threadIndex] = realloc(mScratch[threadIndex], (mSizeX + 1) * 16);
+ mScratchSize[threadIndex] = mSizeX;
+ }
+ // realloc only aligns to 8 bytes so we manually align to 16.
+ buf = (float4 *) ((((intptr_t)mScratch[threadIndex]) + 15) & ~0xf);
+ }
+ float4 *fout = (float4 *)buf;
+ int y = currentY;
+ if ((y > mIradius) && (y < ((int)mSizeY - mIradius))) {
+ const uchar *pi = mIn + (y - mIradius) * stride;
+ OneVFU4(fout, pi, stride, mFp, mIradius * 2 + 1, mSizeX, mUsesSimd);
+ } else {
+ x1 = 0;
+ while(mSizeX > x1) {
+ OneVU4(mSizeY, fout, x1, y, mIn, stride, mFp, mIradius);
+ fout++;
+ x1++;
+ }
+ }
+
+ x1 = xstart;
+ while ((x1 < (uint32_t)mIradius) && (x1 < x2)) {
+ OneHU4(mSizeX, out, x1, buf, mFp, mIradius);
+ out++;
+ x1++;
+ }
+#if defined(ARCH_X86_HAVE_SSSE3)
+ if (mUsesSimd) {
+ if ((x1 + mIradius) < x2) {
+ rsdIntrinsicBlurHFU4_K(out, buf - mIradius, mFp,
+ mIradius * 2 + 1, x1, x2 - mIradius);
+ out += (x2 - mIradius) - x1;
+ x1 = x2 - mIradius;
+ }
+ }
+#endif
+ while(x2 > x1) {
+ OneHU4(mSizeX, out, x1, buf, mFp, mIradius);
+ out++;
+ x1++;
+ }
+}
+
+/**
+ * Full blur of a line of U_8 data.
+ *
+ * @param outPtr Where to store the results
+ * @param xstart The index of the section we're starting to blur.
+ * @param xend The end index of the section.
+ * @param currentY The index of the line we're blurring.
+ */
+void BlurTask::kernelU1(void *outPtr, uint32_t xstart, uint32_t xend, uint32_t currentY) {
+ float buf[4 * 2048];
+ const uint32_t stride = mSizeX * mVectorSize;
+
+ uchar *out = (uchar *)outPtr;
+ uint32_t x1 = xstart;
+ uint32_t x2 = xend;
+
+#if defined(ARCH_ARM_USE_INTRINSICS)
+ if (mUsesSimd && mSizeX >= 16) {
+ // The specialisation for r<=8 has an awkward prefill case, which is
+ // fiddly to resolve, where starting close to the right edge can cause
+ // a read beyond the end of input. So avoid that case here.
+ if (mIradius > 8 || (mSizeX - std::max(0, (int32_t)x1 - 8)) >= 16) {
+ rsdIntrinsicBlurU1_K(out, mIn + stride * currentY, mSizeX, mSizeY,
+ stride, x1, currentY, x2 - x1, mIradius, mIp + mIradius);
+ return;
+ }
+ }
+#endif
+
+ float *fout = (float *)buf;
+ int y = currentY;
+ if ((y > mIradius) && (y < ((int)mSizeY - mIradius -1))) {
+ const uchar *pi = mIn + (y - mIradius) * stride;
+ OneVFU1(fout, pi, stride, mFp, mIradius * 2 + 1, mSizeX, mUsesSimd);
+ } else {
+ x1 = 0;
+ while(mSizeX > x1) {
+ OneVU1(mSizeY, fout, x1, y, mIn, stride, mFp, mIradius);
+ fout++;
+ x1++;
+ }
+ }
+
+ x1 = xstart;
+ while ((x1 < x2) &&
+ ((x1 < (uint32_t)mIradius) || (((uintptr_t)out) & 0x3))) {
+ OneHU1(mSizeX, out, x1, buf, mFp, mIradius);
+ out++;
+ x1++;
+ }
+#if defined(ARCH_X86_HAVE_SSSE3)
+ if (mUsesSimd) {
+ if ((x1 + mIradius) < x2) {
+ uint32_t len = x2 - (x1 + mIradius);
+ len &= ~3;
+
+ // rsdIntrinsicBlurHFU1_K() processes each four float values in |buf| at once, so it
+ // nees to ensure four more values can be accessed in order to avoid accessing
+ // uninitialized buffer.
+ if (len > 4) {
+ len -= 4;
+ rsdIntrinsicBlurHFU1_K(out, ((float *)buf) - mIradius, mFp,
+ mIradius * 2 + 1, x1, x1 + len);
+ out += len;
+ x1 += len;
+ }
+ }
+ }
+#endif
+ while(x2 > x1) {
+ OneHU1(mSizeX, out, x1, buf, mFp, mIradius);
+ out++;
+ x1++;
+ }
+}
+
+void BlurTask::processData(int threadIndex, size_t startX, size_t startY, size_t endX,
+ size_t endY) {
+ for (size_t y = startY; y < endY; y++) {
+ void* outPtr = outArray + (mSizeX * y + startX) * mVectorSize;
+ if (mVectorSize == 4) {
+ kernelU4(outPtr, startX, endX, y, threadIndex);
+ } else {
+ kernelU1(outPtr, startX, endX, y);
+ }
+ }
+}
+
+void RenderScriptToolkit::blur(const uint8_t* in, uint8_t* out, size_t sizeX, size_t sizeY,
+ size_t vectorSize, int radius, const Restriction* restriction) {
+#ifdef ANDROID_RENDERSCRIPT_TOOLKIT_VALIDATE
+ if (!validRestriction(LOG_TAG, sizeX, sizeY, restriction)) {
+ return;
+ }
+ if (radius <= 0 || radius > 25) {
+ ALOGE("The radius should be between 1 and 25. %d provided.", radius);
+ }
+ if (vectorSize != 1 && vectorSize != 4) {
+ ALOGE("The vectorSize should be 1 or 4. %zu provided.", vectorSize);
+ }
+#endif
+
+ BlurTask task(in, out, sizeX, sizeY, vectorSize, processor->getNumberOfThreads(), radius,
+ restriction);
+ processor->doTask(&task);
+}
+
+} // namespace renderscript
+} // namespace android