Merge pull request cats-oss#434 from kitwtnb/add-zoom-blur-filter

Add zoom blur filter

Author: kettsun0123

README.md

@@ -198,7 +198,7 @@ public override fun onCreate(savedInstanceState: Bundle?) {
 - [x] Box Blur
 - [x] Bilateral Blur
 - [ ] Motion Blur
-- [ ] Zoom Blur
+- [x] Zoom Blur
 - [ ] iOS Blur
 - [ ] Median Filter
 - [x] Swirl Distortion

library/src/main/java/jp/co/cyberagent/android/gpuimage/filter/GPUImageZoomBlurFilter.java

@@ -0,0 +1,71 @@
+package jp.co.cyberagent.android.gpuimage.filter;
+
+import android.graphics.PointF;
+import android.opengl.GLES20;
+
+public class GPUImageZoomBlurFilter extends GPUImageFilter {
+    public static final String ZOOM_BLUR_FRAGMENT_SHADER = "" +
+            "varying highp vec2 textureCoordinate;\n" +
+            "\n" +
+            "uniform sampler2D inputImageTexture;\n" +
+            "\n" +
+            "uniform highp vec2 blurCenter;\n" +
+            "uniform highp float blurSize;\n" +
+            "\n" +
+            "void main()\n" +
+            "{\n" +
+            "    // TODO: Do a more intelligent scaling based on resolution here\n" +
+            "    highp vec2 samplingOffset = 1.0/100.0 * (blurCenter - textureCoordinate) * blurSize;\n" +
+            "    \n" +
+            "    lowp vec4 fragmentColor = texture2D(inputImageTexture, textureCoordinate) * 0.18;\n" +
+            "    fragmentColor += texture2D(inputImageTexture, textureCoordinate + samplingOffset) * 0.15;\n" +
+            "    fragmentColor += texture2D(inputImageTexture, textureCoordinate + (2.0 * samplingOffset)) *  0.12;\n" +
+            "    fragmentColor += texture2D(inputImageTexture, textureCoordinate + (3.0 * samplingOffset)) * 0.09;\n" +
+            "    fragmentColor += texture2D(inputImageTexture, textureCoordinate + (4.0 * samplingOffset)) * 0.05;\n" +
+            "    fragmentColor += texture2D(inputImageTexture, textureCoordinate - samplingOffset) * 0.15;\n" +
+            "    fragmentColor += texture2D(inputImageTexture, textureCoordinate - (2.0 * samplingOffset)) *  0.12;\n" +
+            "    fragmentColor += texture2D(inputImageTexture, textureCoordinate - (3.0 * samplingOffset)) * 0.09;\n" +
+            "    fragmentColor += texture2D(inputImageTexture, textureCoordinate - (4.0 * samplingOffset)) * 0.05;\n" +
+            "    \n" +
+            "    gl_FragColor = fragmentColor;\n" +
+            "}\n";
+
+    private PointF blurCenter;
+    private int blurCenterLocation;
+    private float blurSize;
+    private int blurSizeLocation;
+
+    public GPUImageZoomBlurFilter() {
+        this(new PointF(0.5f, 0.5f), 1.0f);
+    }
+
+    public GPUImageZoomBlurFilter(PointF blurCenter, float blurSize) {
+        super(NO_FILTER_VERTEX_SHADER, ZOOM_BLUR_FRAGMENT_SHADER);
+        this.blurCenter = blurCenter;
+        this.blurSize = blurSize;
+    }
+
+    @Override
+    public void onInit() {
+        super.onInit();
+        blurCenterLocation = GLES20.glGetUniformLocation(getProgram(), "blurCenter");
+        blurSizeLocation = GLES20.glGetUniformLocation(getProgram(), "blurSize");
+    }
+
+    @Override
+    public void onInitialized() {
+        super.onInitialized();
+        setBlurCenter(blurCenter);
+        setBlurSize(blurSize);
+    }
+
+    public void setBlurCenter(final PointF blurCenter) {
+        this.blurCenter = blurCenter;
+        setPoint(blurCenterLocation, blurCenter);
+    }
+
+    public void setBlurSize(final float blurSize) {
+        this.blurSize = blurSize;
+        setFloat(blurSizeLocation, blurSizeLocation);
+    }
+}

sample/src/main/java/jp/co/cyberagent/android/gpuimage/sample/GPUImageFilterTools.kt

@@ -113,6 +113,8 @@ object GPUImageFilterTools {
 
             addFilter("Bilateral Blur", FilterType.BILATERAL_BLUR)
 
+            addFilter("Zoom Blur", FilterType.ZOOM_BLUR)
+
             addFilter("Transform (2-D)", FilterType.TRANSFORM2D)
 
             addFilter("Solarize", FilterType.SOLARIZE)
@@ -301,6 +303,7 @@ object GPUImageFilterTools {
             FilterType.LEVELS_FILTER_MIN -> GPUImageLevelsFilter()
             FilterType.HALFTONE -> GPUImageHalftoneFilter()
             FilterType.BILATERAL_BLUR -> GPUImageBilateralBlurFilter()
+            FilterType.ZOOM_BLUR -> GPUImageZoomBlurFilter()
             FilterType.TRANSFORM2D -> GPUImageTransformFilter()
             FilterType.SOLARIZE -> GPUImageSolarizeFilter()
             FilterType.VIBRANCE -> GPUImageVibranceFilter()
@@ -327,7 +330,7 @@ object GPUImageFilterTools {
         BLEND_DIFFERENCE, BLEND_DISSOLVE, BLEND_EXCLUSION, BLEND_SOURCE_OVER, BLEND_HARD_LIGHT, BLEND_LIGHTEN, BLEND_ADD, BLEND_DIVIDE, BLEND_MULTIPLY, BLEND_OVERLAY, BLEND_SCREEN, BLEND_ALPHA,
         BLEND_COLOR, BLEND_HUE, BLEND_SATURATION, BLEND_LUMINOSITY, BLEND_LINEAR_BURN, BLEND_SOFT_LIGHT, BLEND_SUBTRACT, BLEND_CHROMA_KEY, BLEND_NORMAL, LOOKUP_AMATORKA,
         GAUSSIAN_BLUR, CROSSHATCH, BOX_BLUR, CGA_COLORSPACE, DILATION, KUWAHARA, RGB_DILATION, SKETCH, TOON, SMOOTH_TOON, BULGE_DISTORTION, GLASS_SPHERE, HAZE, LAPLACIAN, NON_MAXIMUM_SUPPRESSION,
-        SPHERE_REFRACTION, SWIRL, WEAK_PIXEL_INCLUSION, FALSE_COLOR, COLOR_BALANCE, LEVELS_FILTER_MIN, BILATERAL_BLUR, HALFTONE, TRANSFORM2D, SOLARIZE, VIBRANCE
+        SPHERE_REFRACTION, SWIRL, WEAK_PIXEL_INCLUSION, FALSE_COLOR, COLOR_BALANCE, LEVELS_FILTER_MIN, BILATERAL_BLUR, ZOOM_BLUR, HALFTONE, TRANSFORM2D, SOLARIZE, VIBRANCE
     }
 
     private class FilterList {