SkImage::NewFromYUVTexturesCopy

gm/imagefromyuvtextures.cpp

Index: gm/imagefromyuvtextures.cpp
diff --git a/gm/imagefromyuvtextures.cpp b/gm/imagefromyuvtextures.cpp
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+
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+// This test only works with the GPU backend.
+
+#include "gm.h"
+
+#if SK_SUPPORT_GPU
+
+#include "GrContext.h"
+#include "gl/GrGLInterface.h"
+#include "gl/GrGLUtil.h"
+#include "GrTest.h"
+#include "SkBitmap.h"
+#include "SkGradientShader.h"
+#include "SkImage.h"
+
+namespace skiagm {
+class ImageFromYUVTextures : public GM {
+public:
+    ImageFromYUVTextures() {
+        this->setBGColor(0xFFFFFFFF);
+    }
+
+protected:
+    SkString onShortName() override {
+        return SkString("image_from_yuv_textures");
+    }
+
+    SkISize onISize() override {
+        return SkISize::Make(50, 135);
+    }
+
+    void onOnceBeforeDraw() override {
+        // We create an RGB bitmap and then extract YUV bmps where the U and V bitmaps are
+        // subsampled by 2 in both dimensions.
+        SkPaint paint;
+        static const SkColor kColors[] =
+            { SK_ColorBLUE, SK_ColorYELLOW, SK_ColorGREEN, SK_ColorWHITE };
+        paint.setShader(SkGradientShader::CreateRadial(SkPoint::Make(0,0), kBmpSize / 2.f, kColors,
+                                                       NULL, SK_ARRAY_COUNT(kColors),
+                                                       SkShader::kMirror_TileMode))->unref();
+        SkBitmap rgbBmp;
+        rgbBmp.allocN32Pixels(kBmpSize, kBmpSize, true);
+        SkCanvas canvas(rgbBmp);
+        canvas.drawPaint(paint);
+        SkPMColor* rgbColors = static_cast<SkPMColor*>(rgbBmp.getPixels());
+
+        SkImageInfo yinfo = SkImageInfo::MakeA8(kBmpSize, kBmpSize);
+        fYUVBmps[0].allocPixels(yinfo);
+        SkImageInfo uinfo = SkImageInfo::MakeA8(kBmpSize / 2, kBmpSize / 2);
+        fYUVBmps[1].allocPixels(uinfo);
+        SkImageInfo vinfo = SkImageInfo::MakeA8(kBmpSize / 2, kBmpSize / 2);
+        fYUVBmps[2].allocPixels(vinfo);
+        unsigned char* yPixels;
+        signed char* uvPixels[2];
+        yPixels = static_cast<unsigned char*>(fYUVBmps[0].getPixels());
+        uvPixels[0] = static_cast<signed char*>(fYUVBmps[1].getPixels());
+        uvPixels[1] = static_cast<signed char*>(fYUVBmps[2
+        ].getPixels());
+
+        // Here we encode using the NTC encoding (even though we will draw it with all the supported
+        // yuv color spaces when converted back to RGB)
+        for (int i = 0; i < kBmpSize * kBmpSize; ++i) {
+            yPixels[i] = static_cast<unsigned char>(0.299f * SkGetPackedR32(rgbColors[i]) +
+                                                    0.587f * SkGetPackedG32(rgbColors[i]) +
+                                                    0.114f * SkGetPackedB32(rgbColors[i]));
+        }
+        for (int j = 0; j < kBmpSize / 2; ++j) {
+            for (int i = 0; i < kBmpSize / 2; ++i) {
+                // Average together 4 pixels of RGB.
+                int rgb[] = { 0, 0, 0 };
+                for (int y = 0; y < 2; ++y) {
+                    for (int x = 0; x < 2; ++x) {
+                        int rgbIndex = (2 * j + y) * kBmpSize + 2 * i + x;
+                        rgb[0] += SkGetPackedR32(rgbColors[rgbIndex]);
+                        rgb[1] += SkGetPackedG32(rgbColors[rgbIndex]);
+                        rgb[2] += SkGetPackedB32(rgbColors[rgbIndex]);
+                    }
+                }
+                for (int c = 0; c < 3; ++c) {
+                    rgb[c] /= 4;
+                }
+                int uvIndex = j * kBmpSize / 2 + i;
+                uvPixels[0][uvIndex] = static_cast<signed char>(
+                    ((-38 * rgb[0] -  74 * rgb[1] + 112 * rgb[2] + 128) >> 8) + 128);
+                uvPixels[1][uvIndex] = static_cast<signed char>(
+                    ((112 * rgb[0] -  94 * rgb[1] -  18 * rgb[2] + 128) >> 8) + 128);
+            }
+        }
+        fRGBImage.reset(SkImage::NewRasterCopy(rgbBmp.info(), rgbColors, rgbBmp.rowBytes()));
+    }
+
+    void createYUVTextures(GrContext* context, GrGLuint yuvIDs[3]) {
+        GrTestTarget tt;
+        context->getTestTarget(&tt);
+        if (!tt.target()) {
+            SkDEBUGFAIL("Couldn't get Gr test target.");
+            return;
+        }
+
+        // We currently hav only implemented the texture uploads for GL.
+        const GrGLInterface* gl = tt.glInterface();
+        if (!gl) {
+            return;
+        }
+
+        GR_GL_CALL(gl, GenTextures(3, yuvIDs));
+        GR_GL_CALL(gl, ActiveTexture(GR_GL_TEXTURE0));
+        GR_GL_CALL(gl, PixelStorei(GR_GL_UNPACK_ALIGNMENT, 1));
+        for (int i = 0; i < 3; ++i) {
+            GR_GL_CALL(gl, BindTexture(GR_GL_TEXTURE_2D, yuvIDs[i]));
+            GR_GL_CALL(gl, TexParameteri(GR_GL_TEXTURE_2D, GR_GL_TEXTURE_MAG_FILTER,
+                                         GR_GL_NEAREST));
+            GR_GL_CALL(gl, TexParameteri(GR_GL_TEXTURE_2D, GR_GL_TEXTURE_MIN_FILTER,
+                                         GR_GL_NEAREST));
+            GR_GL_CALL(gl, TexParameteri(GR_GL_TEXTURE_2D, GR_GL_TEXTURE_WRAP_S,
+                                         GR_GL_CLAMP_TO_EDGE));
+            GR_GL_CALL(gl, TexParameteri(GR_GL_TEXTURE_2D, GR_GL_TEXTURE_WRAP_T,
+                                         GR_GL_CLAMP_TO_EDGE));
+            SkASSERT(fYUVBmps[i].width() == SkToInt(fYUVBmps[i].rowBytes()));
+            GR_GL_CALL(gl, TexImage2D(GR_GL_TEXTURE_2D, 0, GR_GL_RED, fYUVBmps[i].width(),
+                                      fYUVBmps[i].height(), 0, GR_GL_RED, GR_GL_UNSIGNED_BYTE,
+                                      fYUVBmps[i].getPixels()));
+        }
+        context->resetContext();
+    }
+
+    void deleteYUVTextures(GrContext* context, const GrGLuint yuvIDs[3]) {
+        GrTestTarget tt;
+        context->getTestTarget(&tt);
+        if (!tt.target()) {
+            SkDEBUGFAIL("Couldn't get Gr test target.");
+            return;
+        }
+
+        const GrGLInterface* gl = tt.glInterface();
+        if (!gl) {
+            return;
+        }
+        GR_GL_CALL(gl, DeleteTextures(3, yuvIDs));
+        context->resetContext();
+    }
+
+    void onDraw(SkCanvas* canvas) override {
+        GrRenderTarget* rt = canvas->internal_private_accessTopLayerRenderTarget();
+        GrContext* context;
+        if (!rt || !(context = rt->getContext())) {
+            this->drawGpuOnlyMessage(canvas);
+            return;
+        }
+
+        GrGLuint yuvIDs[3];
+        this->createYUVTextures(context, yuvIDs);
+
+        static const SkScalar kPad = 10.f;
+
+        GrBackendObject backendTextureObjects[] = {
+            static_cast<GrBackendObject>(yuvIDs[0]),
+            static_cast<GrBackendObject>(yuvIDs[1]),
+            static_cast<GrBackendObject>(yuvIDs[2])
+        };
+        SkISize sizes[] = {
+            { fYUVBmps[0].width(), fYUVBmps[0].height()},
+            { fYUVBmps[1].width(), fYUVBmps[1].height()},
+            { fYUVBmps[2].width(), fYUVBmps[2].height()},
+        };
+        SkTArray<SkImage*> images;
+        images.push_back(SkRef(fRGBImage.get()));
+        for (int space = kJPEG_SkYUVColorSpace; space <= kLastEnum_SkYUVColorSpace; ++space) {
+            images.push_back(SkImage::NewFromYUVTexturesCopy(context,
+                                                             static_cast<SkYUVColorSpace>(space),
+                                                             backendTextureObjects, sizes,
+                                                             kTopLeft_GrSurfaceOrigin));
+        }
+        this->deleteYUVTextures(context, yuvIDs);
+        for (int i = 0; i < images.count(); ++ i) {
+            SkScalar y = (i + 1) * kPad + i * fYUVBmps[0].height();
+            SkScalar x = kPad;
+
+            canvas->drawImage(images[i], x, y);
+            images[i]->unref();
+            images[i] = NULL;
+        }
+     }
+
+private:
+    SkAutoTUnref<SkImage>  fRGBImage;
+    SkBitmap               fYUVBmps[3];
+
+    static const int kBmpSize = 32;
+
+    typedef GM INHERITED;
+};
+
+DEF_GM( return SkNEW(ImageFromYUVTextures); )
+}
+
+#endif