1 /* 2 * Copyright 2015 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 // This test only works with the GPU backend. 9 10 #include "gm.h" 11 12 #if SK_SUPPORT_GPU 13 14 #include "GrContext.h" 15 #include "GrContextPriv.h" 16 #include "GrGpu.h" 17 #include "GrTest.h" 18 #include "SkBitmap.h" 19 #include "SkGradientShader.h" 20 #include "SkImage.h" 21 22 namespace skiagm { 23 class ImageFromYUVTextures : public GM { 24 public: 25 ImageFromYUVTextures() { 26 this->setBGColor(0xFFFFFFFF); 27 } 28 29 protected: 30 SkString onShortName() override { 31 return SkString("image_from_yuv_textures"); 32 } 33 34 SkISize onISize() override { 35 return SkISize::Make(50, 175); 36 } 37 38 void onOnceBeforeDraw() override { 39 // We create an RGB bitmap and then extract YUV bmps where the U and V bitmaps are 40 // subsampled by 2 in both dimensions. 41 SkPaint paint; 42 constexpr SkColor kColors[] = 43 { SK_ColorBLUE, SK_ColorYELLOW, SK_ColorGREEN, SK_ColorWHITE }; 44 paint.setShader(SkGradientShader::MakeRadial(SkPoint::Make(0,0), kBmpSize / 2.f, kColors, 45 nullptr, SK_ARRAY_COUNT(kColors), 46 SkShader::kMirror_TileMode)); 47 SkBitmap rgbBmp; 48 rgbBmp.allocN32Pixels(kBmpSize, kBmpSize, true); 49 SkCanvas canvas(rgbBmp); 50 canvas.drawPaint(paint); 51 SkPMColor* rgbColors = static_cast<SkPMColor*>(rgbBmp.getPixels()); 52 53 SkImageInfo yinfo = SkImageInfo::MakeA8(kBmpSize, kBmpSize); 54 fYUVBmps[0].allocPixels(yinfo); 55 SkImageInfo uinfo = SkImageInfo::MakeA8(kBmpSize / 2, kBmpSize / 2); 56 fYUVBmps[1].allocPixels(uinfo); 57 SkImageInfo vinfo = SkImageInfo::MakeA8(kBmpSize / 2, kBmpSize / 2); 58 fYUVBmps[2].allocPixels(vinfo); 59 unsigned char* yPixels; 60 signed char* uvPixels[2]; 61 yPixels = static_cast<unsigned char*>(fYUVBmps[0].getPixels()); 62 uvPixels[0] = static_cast<signed char*>(fYUVBmps[1].getPixels()); 63 uvPixels[1] = static_cast<signed char*>(fYUVBmps[2].getPixels()); 64 65 // Here we encode using the NTC encoding (even though we will draw it with all the supported 66 // yuv color spaces when converted back to RGB) 67 for (int i = 0; i < kBmpSize * kBmpSize; ++i) { 68 yPixels[i] = static_cast<unsigned char>(0.299f * SkGetPackedR32(rgbColors[i]) + 69 0.587f * SkGetPackedG32(rgbColors[i]) + 70 0.114f * SkGetPackedB32(rgbColors[i])); 71 } 72 for (int j = 0; j < kBmpSize / 2; ++j) { 73 for (int i = 0; i < kBmpSize / 2; ++i) { 74 // Average together 4 pixels of RGB. 75 int rgb[] = { 0, 0, 0 }; 76 for (int y = 0; y < 2; ++y) { 77 for (int x = 0; x < 2; ++x) { 78 int rgbIndex = (2 * j + y) * kBmpSize + 2 * i + x; 79 rgb[0] += SkGetPackedR32(rgbColors[rgbIndex]); 80 rgb[1] += SkGetPackedG32(rgbColors[rgbIndex]); 81 rgb[2] += SkGetPackedB32(rgbColors[rgbIndex]); 82 } 83 } 84 for (int c = 0; c < 3; ++c) { 85 rgb[c] /= 4; 86 } 87 int uvIndex = j * kBmpSize / 2 + i; 88 uvPixels[0][uvIndex] = static_cast<signed char>( 89 ((-38 * rgb[0] - 74 * rgb[1] + 112 * rgb[2] + 128) >> 8) + 128); 90 uvPixels[1][uvIndex] = static_cast<signed char>( 91 ((112 * rgb[0] - 94 * rgb[1] - 18 * rgb[2] + 128) >> 8) + 128); 92 } 93 } 94 fRGBImage = SkImage::MakeRasterCopy(SkPixmap(rgbBmp.info(), rgbColors, rgbBmp.rowBytes())); 95 } 96 97 void createYUVTextures(GrContext* context, GrBackendTexture yuvTextures[3]) { 98 GrGpu* gpu = context->contextPriv().getGpu(); 99 if (!gpu) { 100 return; 101 } 102 103 for (int i = 0; i < 3; ++i) { 104 SkASSERT(fYUVBmps[i].width() == SkToInt(fYUVBmps[i].rowBytes())); 105 yuvTextures[i] = gpu->createTestingOnlyBackendTexture(fYUVBmps[i].getPixels(), 106 fYUVBmps[i].width(), 107 fYUVBmps[i].height(), 108 kAlpha_8_GrPixelConfig, 109 false, GrMipMapped::kNo); 110 } 111 context->resetContext(); 112 } 113 114 void deleteYUVTextures(GrContext* context, GrBackendTexture yuvTextures[3]) { 115 116 GrGpu* gpu = context->contextPriv().getGpu(); 117 if (!gpu) { 118 return; 119 } 120 121 for (int i = 0; i < 3; ++i) { 122 if (yuvTextures[i].isValid()) { 123 gpu->deleteTestingOnlyBackendTexture(&yuvTextures[i]); 124 } 125 } 126 127 context->resetContext(); 128 } 129 130 void onDraw(SkCanvas* canvas) override { 131 GrContext* context = canvas->getGrContext(); 132 if (!context) { 133 skiagm::GM::DrawGpuOnlyMessage(canvas); 134 return; 135 } 136 137 138 constexpr SkScalar kPad = 10.f; 139 140 SkISize sizes[] = { 141 { fYUVBmps[0].width(), fYUVBmps[0].height()}, 142 { fYUVBmps[1].width(), fYUVBmps[1].height()}, 143 { fYUVBmps[2].width(), fYUVBmps[2].height()}, 144 }; 145 SkTArray<sk_sp<SkImage>> images; 146 images.push_back(fRGBImage); 147 for (int space = kJPEG_SkYUVColorSpace; space <= kLastEnum_SkYUVColorSpace; ++space) { 148 GrBackendTexture yuvTextures[3]; 149 this->createYUVTextures(context, yuvTextures); 150 images.push_back(SkImage::MakeFromYUVTexturesCopy(context, 151 static_cast<SkYUVColorSpace>(space), 152 yuvTextures, sizes, 153 kTopLeft_GrSurfaceOrigin)); 154 this->deleteYUVTextures(context, yuvTextures); 155 } 156 for (int i = 0; i < images.count(); ++ i) { 157 SkScalar y = (i + 1) * kPad + i * fYUVBmps[0].height(); 158 SkScalar x = kPad; 159 160 canvas->drawImage(images[i].get(), x, y); 161 } 162 } 163 164 private: 165 sk_sp<SkImage> fRGBImage; 166 SkBitmap fYUVBmps[3]; 167 168 static constexpr int kBmpSize = 32; 169 170 typedef GM INHERITED; 171 }; 172 173 DEF_GM(return new ImageFromYUVTextures;) 174 } 175 176 #endif 177
