diff --git a/internal/test-utils-core/src/androidMain/kotlin/com/github/panpf/sketch/test/utils/bitmaps.kt b/internal/test-utils-core/src/androidMain/kotlin/com/github/panpf/sketch/test/utils/bitmaps.kt
index f7836ee1ab..5673404c27 100644
--- a/internal/test-utils-core/src/androidMain/kotlin/com/github/panpf/sketch/test/utils/bitmaps.kt
+++ b/internal/test-utils-core/src/androidMain/kotlin/com/github/panpf/sketch/test/utils/bitmaps.kt
@@ -19,6 +19,15 @@ package com.github.panpf.sketch.test.utils
 import android.graphics.Bitmap
 
 
+fun Bitmap.toSizeString(): String = "${width}x${height}"
+
+@Suppress("USELESS_ELVIS")
+val Bitmap.configOrNull: Bitmap.Config?
+    get() = config ?: null
+
+fun Bitmap.toShortInfoString(): String = "Bitmap(${width}x${height},$configOrNull)"
+
+
 val Bitmap.cornerA: Int
     get() = getPixel(0, 0)
 val Bitmap.cornerB: Int
@@ -32,12 +41,4 @@ fun Bitmap.corners(block: Bitmap.() -> List<Int>): List<Int> {
     return block(this)
 }
 
-fun Bitmap.toSizeString(): String = "${width}x${height}"
-
-fun Bitmap.corners(): List<Int> = listOf(cornerA, cornerB, cornerC, cornerD)
-
-@Suppress("USELESS_ELVIS")
-val Bitmap.configOrNull: Bitmap.Config?
-    get() = config ?: null
-
-fun Bitmap.toShortInfoString(): String = "Bitmap(${width}x${height},$configOrNull)"
\ No newline at end of file
+fun Bitmap.corners(): List<Int> = listOf(cornerA, cornerB, cornerC, cornerD)
\ No newline at end of file
diff --git a/internal/test-utils-core/src/androidMain/kotlin/com/github/panpf/sketch/test/utils/images.android.kt b/internal/test-utils-core/src/androidMain/kotlin/com/github/panpf/sketch/test/utils/images.android.kt
index dfbfac6dba..142e67debf 100644
--- a/internal/test-utils-core/src/androidMain/kotlin/com/github/panpf/sketch/test/utils/images.android.kt
+++ b/internal/test-utils-core/src/androidMain/kotlin/com/github/panpf/sketch/test/utils/images.android.kt
@@ -1,6 +1,7 @@
 package com.github.panpf.sketch.test.utils
 
 import android.graphics.Bitmap
+import androidx.core.graphics.get
 import com.github.panpf.sketch.AndroidBitmapImage
 import com.github.panpf.sketch.Image
 import com.github.panpf.sketch.asSketchImage
@@ -13,4 +14,13 @@ actual fun createImage(width: Int, height: Int): Image {
 
 actual fun createCacheValue(image: Image, extras: Map<String, Any?>): MemoryCache.Value {
     return AndroidBitmapImageValue(image = image as AndroidBitmapImage, extras = extras)
+}
+
+actual fun Image.hasAlpha(): Boolean = (this as AndroidBitmapImage).bitmap.hasAlpha()
+
+/**
+ * Returns the Color at the specified location.
+ */
+actual fun Image.getPixel(x: Int, y: Int): Int {
+    return (this as AndroidBitmapImage).bitmap.get(x, y)
 }
\ No newline at end of file
diff --git a/internal/test-utils-core/src/commonMain/kotlin/com/github/panpf/sketch/test/utils/images.common.kt b/internal/test-utils-core/src/commonMain/kotlin/com/github/panpf/sketch/test/utils/images.common.kt
index ea806e01ac..bbd95e55f9 100644
--- a/internal/test-utils-core/src/commonMain/kotlin/com/github/panpf/sketch/test/utils/images.common.kt
+++ b/internal/test-utils-core/src/commonMain/kotlin/com/github/panpf/sketch/test/utils/images.common.kt
@@ -5,4 +5,26 @@ import com.github.panpf.sketch.cache.MemoryCache
 
 expect fun createImage(width: Int, height: Int): Image
 
-expect fun createCacheValue(image: Image, extras: Map<String, Any?>): MemoryCache.Value
\ No newline at end of file
+expect fun createCacheValue(image: Image, extras: Map<String, Any?>): MemoryCache.Value
+
+val Image.cornerA: Int
+    get() = getPixel(0, 0)
+val Image.cornerB: Int
+    get() = getPixel(width - 1, 0)
+val Image.cornerC: Int
+    get() = getPixel(width - 1, height - 1)
+val Image.cornerD: Int
+    get() = getPixel(0, height - 1)
+
+fun Image.corners(block: Image.() -> List<Int>): List<Int> {
+    return block(this)
+}
+
+fun Image.corners(): List<Int> = listOf(cornerA, cornerB, cornerC, cornerD)
+
+expect fun Image.hasAlpha(): Boolean
+
+/**
+ * Returns the Color at the specified location.
+ */
+expect fun Image.getPixel(x: Int, y: Int): Int
\ No newline at end of file
diff --git a/internal/test-utils-core/src/nonAndroidMain/kotlin/com/github/panpf/sketch/test/utils/images.nonAndroid.kt b/internal/test-utils-core/src/nonAndroidMain/kotlin/com/github/panpf/sketch/test/utils/images.nonAndroid.kt
index 1ace1ecfc2..250991e8e0 100644
--- a/internal/test-utils-core/src/nonAndroidMain/kotlin/com/github/panpf/sketch/test/utils/images.nonAndroid.kt
+++ b/internal/test-utils-core/src/nonAndroidMain/kotlin/com/github/panpf/sketch/test/utils/images.nonAndroid.kt
@@ -6,6 +6,8 @@ import com.github.panpf.sketch.SkiaBitmapImage
 import com.github.panpf.sketch.asSketchImage
 import com.github.panpf.sketch.cache.MemoryCache
 import com.github.panpf.sketch.cache.SkiaBitmapImageValue
+import com.github.panpf.sketch.util.getPixel
+import com.github.panpf.sketch.util.hasAlpha
 
 actual fun createImage(width: Int, height: Int): Image {
     return SkiaBitmap().apply {
@@ -15,4 +17,14 @@ actual fun createImage(width: Int, height: Int): Image {
 
 actual fun createCacheValue(image: Image, extras: Map<String, Any?>): MemoryCache.Value {
     return SkiaBitmapImageValue(image = image as SkiaBitmapImage, extras = extras)
+}
+
+//actual fun Image.hasAlpha(): Boolean = !(this as SkiaBitmapImage).bitmap.isOpaque
+actual fun Image.hasAlpha(): Boolean = (this as SkiaBitmapImage).bitmap.hasAlpha()
+
+/**
+ * Returns the Color at the specified location.
+ */
+actual fun Image.getPixel(x: Int, y: Int): Int {
+    return (this as SkiaBitmapImage).bitmap.getPixel(x, y)
 }
\ No newline at end of file
diff --git a/sketch-core/src/androidInstrumentedTest/kotlin/com/github/panpf/sketch/core/android/test/transform/BlurTransformationTest.kt b/sketch-core/src/androidInstrumentedTest/kotlin/com/github/panpf/sketch/core/android/test/transform/BlurTransformationTest.kt
deleted file mode 100644
index c718dc5994..0000000000
--- a/sketch-core/src/androidInstrumentedTest/kotlin/com/github/panpf/sketch/core/android/test/transform/BlurTransformationTest.kt
+++ /dev/null
@@ -1,230 +0,0 @@
-/*
- * Copyright (C) 2024 panpf <panpfpanpf@outlook.com>
- *
- * 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.
- */
-
-package com.github.panpf.sketch.core.android.test.transform
-
-import android.graphics.BitmapFactory
-import android.graphics.Color
-import androidx.core.graphics.ColorUtils
-import androidx.test.ext.junit.runners.AndroidJUnit4
-import com.github.panpf.sketch.asSketchImage
-import com.github.panpf.sketch.getBitmapOrThrow
-import com.github.panpf.sketch.images.ResourceImages
-import com.github.panpf.sketch.request.ImageRequest
-import com.github.panpf.sketch.test.singleton.getTestContextAndSketch
-import com.github.panpf.sketch.test.utils.corners
-import com.github.panpf.sketch.test.utils.size
-import com.github.panpf.sketch.test.utils.toRequestContext
-import com.github.panpf.sketch.transform.BlurTransformation
-import com.github.panpf.sketch.transform.createBlurTransformed
-import com.github.panpf.sketch.transform.getBlurTransformed
-import com.github.panpf.sketch.util.Size
-import com.github.panpf.tools4j.test.ktx.assertThrow
-import kotlinx.coroutines.runBlocking
-import org.junit.Assert
-import org.junit.Test
-import org.junit.runner.RunWith
-
-@RunWith(AndroidJUnit4::class)
-class BlurTransformationTest {
-
-    @Test
-    fun testConstructor() {
-        assertThrow(IllegalArgumentException::class) {
-            BlurTransformation(0)
-        }
-        assertThrow(IllegalArgumentException::class) {
-            BlurTransformation(101)
-        }
-        assertThrow(IllegalArgumentException::class) {
-            BlurTransformation(
-                hasAlphaBitmapBgColor = ColorUtils.setAlphaComponent(Color.BLACK, 244)
-            )
-        }
-        BlurTransformation(12).apply {
-            Assert.assertEquals(12, radius)
-            Assert.assertEquals(Color.BLACK, hasAlphaBitmapBgColor)
-            Assert.assertNull(maskColor)
-        }
-        BlurTransformation(20, hasAlphaBitmapBgColor = null, maskColor = Color.GREEN).apply {
-            Assert.assertEquals(20, radius)
-            Assert.assertNull(hasAlphaBitmapBgColor)
-            Assert.assertEquals(Color.GREEN, maskColor)
-        }
-    }
-
-    @Test
-    fun testKeyAndToString() {
-        BlurTransformation().apply {
-            Assert.assertEquals("BlurTransformation(15,${Color.BLACK},null)", key)
-            Assert.assertEquals("BlurTransformation(15,${Color.BLACK},null)", toString())
-        }
-        BlurTransformation(20, hasAlphaBitmapBgColor = null, maskColor = Color.GREEN).apply {
-            Assert.assertEquals("BlurTransformation(20,null,${Color.GREEN})", key)
-            Assert.assertEquals("BlurTransformation(20,null,${Color.GREEN})", toString())
-        }
-    }
-
-    @Test
-    fun testTransform() {
-        val (context, sketch) = getTestContextAndSketch()
-        val request = ImageRequest(context, ResourceImages.jpeg.uri)
-
-        // isMutable false
-        val inBitmap = context.assets.open(ResourceImages.jpeg.resourceName).use {
-            BitmapFactory.decodeStream(it)
-        }.apply {
-            Assert.assertNotEquals(
-                listOf(Color.TRANSPARENT, Color.TRANSPARENT, Color.TRANSPARENT, Color.TRANSPARENT),
-                this.corners()
-            )
-            Assert.assertEquals(
-                Size(1291, 1936),
-                this.size
-            )
-            Assert.assertFalse(this.isMutable)
-        }
-        val inBitmapCorners = inBitmap.corners()
-        runBlocking {
-            BlurTransformation(
-                30,
-                maskColor = ColorUtils.setAlphaComponent(Color.BLUE, 80)
-            ).transform(sketch, request.toRequestContext(sketch), inBitmap.asSketchImage())
-        }.apply {
-            Assert.assertNotSame(inBitmap, image.getBitmapOrThrow())
-            Assert.assertNotEquals(inBitmapCorners, image.getBitmapOrThrow().corners())
-            Assert.assertEquals(Size(1291, 1936), image.getBitmapOrThrow().size)
-            Assert.assertEquals(
-                createBlurTransformed(
-                    30,
-                    Color.BLACK,
-                    ColorUtils.setAlphaComponent(Color.BLUE, 80)
-                ), transformed
-            )
-        }
-
-        // isMutable true
-        val mutableInBitmap = context.assets.open(ResourceImages.jpeg.resourceName).use {
-            BitmapFactory.decodeStream(it, null, BitmapFactory.Options().apply {
-                inMutable = true
-            })
-        }!!.apply {
-            Assert.assertTrue(this.isMutable)
-        }
-        runBlocking {
-            BlurTransformation(30).transform(
-                sketch,
-                request.toRequestContext(sketch),
-                mutableInBitmap.asSketchImage()
-            )
-        }.apply {
-            Assert.assertSame(mutableInBitmap, this.image.getBitmapOrThrow())
-        }
-
-        // hasAlphaBitmapBgColor
-        val hasAlphaBitmap1 = context.assets.open(ResourceImages.png.resourceName).use {
-            BitmapFactory.decodeStream(it, null, null)
-        }!!.apply {
-            Assert.assertTrue(this.hasAlpha())
-        }
-        val hasAlphaBitmapBlurred1 = runBlocking {
-            BlurTransformation(30).transform(
-                sketch,
-                request.toRequestContext(sketch),
-                hasAlphaBitmap1.asSketchImage()
-            )
-        }.apply {
-            Assert.assertTrue(this.image.getBitmapOrThrow().hasAlpha())
-        }.image.getBitmapOrThrow()
-
-        val hasAlphaBitmap2 = context.assets.open(ResourceImages.png.resourceName).use {
-            BitmapFactory.decodeStream(it, null, null)
-        }!!.apply {
-            Assert.assertTrue(this.hasAlpha())
-        }
-        val hasAlphaBitmapBlurred2 = runBlocking {
-            BlurTransformation(30, hasAlphaBitmapBgColor = null)
-                .transform(
-                    sketch,
-                    request.toRequestContext(sketch),
-                    hasAlphaBitmap2.asSketchImage()
-                )
-        }.apply {
-            Assert.assertTrue(this.image.getBitmapOrThrow().hasAlpha())
-        }.image.getBitmapOrThrow()
-        Assert.assertNotEquals(hasAlphaBitmapBlurred1.corners(), hasAlphaBitmapBlurred2.corners())
-    }
-
-    @Test
-    fun testEqualsAndHashCode() {
-        val element1 = BlurTransformation(20, null, null)
-        val element11 = BlurTransformation(20, null, null)
-        val element2 = BlurTransformation(10, Color.GREEN, null)
-        val element3 = BlurTransformation(20, Color.BLACK, Color.BLUE)
-        val element4 = BlurTransformation(20, Color.BLACK, Color.WHITE)
-
-        Assert.assertNotSame(element1, element11)
-        Assert.assertNotSame(element1, element2)
-        Assert.assertNotSame(element1, element3)
-        Assert.assertNotSame(element1, element4)
-        Assert.assertNotSame(element11, element2)
-        Assert.assertNotSame(element11, element3)
-        Assert.assertNotSame(element11, element4)
-        Assert.assertNotSame(element2, element3)
-        Assert.assertNotSame(element2, element4)
-        Assert.assertNotSame(element3, element4)
-
-        Assert.assertEquals(element1, element1)
-        Assert.assertEquals(element1, element11)
-        Assert.assertNotEquals(element1, element2)
-        Assert.assertNotEquals(element1, element3)
-        Assert.assertNotEquals(element1, element4)
-        Assert.assertNotEquals(element2, element11)
-        Assert.assertNotEquals(element2, element3)
-        Assert.assertNotEquals(element2, element4)
-        Assert.assertNotEquals(element3, element4)
-        Assert.assertNotEquals(element1, null)
-        Assert.assertNotEquals(element1, Any())
-
-        Assert.assertEquals(element1.hashCode(), element1.hashCode())
-        Assert.assertEquals(element1.hashCode(), element11.hashCode())
-        Assert.assertNotEquals(element1.hashCode(), element2.hashCode())
-        Assert.assertNotEquals(element2.hashCode(), element11.hashCode())
-        Assert.assertNotEquals(element2.hashCode(), element3.hashCode())
-    }
-
-    @Test
-    fun testBlurTransformed() {
-        Assert.assertEquals("BlurTransformed(1,null,null)", createBlurTransformed(1, null, null))
-        Assert.assertEquals("BlurTransformed(2,null,null)", createBlurTransformed(2, null, null))
-        Assert.assertEquals("BlurTransformed(4,null,null)", createBlurTransformed(4, null, null))
-        Assert.assertEquals("BlurTransformed(8,null,null)", createBlurTransformed(8, null, null))
-
-        Assert.assertEquals(null, listOf<String>().getBlurTransformed())
-        Assert.assertEquals(
-            "BlurTransformed(2,null,null)",
-            listOf(createBlurTransformed(2, null, null)).getBlurTransformed()
-        )
-        Assert.assertEquals(
-            "BlurTransformed(16,null,null)",
-            listOf(
-                "disruptive1",
-                createBlurTransformed(16, null, null),
-                "disruptive2"
-            ).getBlurTransformed()
-        )
-    }
-}
\ No newline at end of file
diff --git a/sketch-core/src/commonMain/kotlin/com/github/panpf/sketch/transform/BlurTransformation.common.kt b/sketch-core/src/commonMain/kotlin/com/github/panpf/sketch/transform/BlurTransformation.common.kt
index de9d4784f4..8d1b7448d4 100644
--- a/sketch-core/src/commonMain/kotlin/com/github/panpf/sketch/transform/BlurTransformation.common.kt
+++ b/sketch-core/src/commonMain/kotlin/com/github/panpf/sketch/transform/BlurTransformation.common.kt
@@ -31,6 +31,8 @@ internal expect fun blurTransformation(
 
 /**
  * Bitmap blur transformation
+ *
+ * @see com.github.panpf.sketch.core.common.test.transform.BlurTransformationTest
  */
 class BlurTransformation constructor(
     /** Blur radius */
@@ -86,12 +88,27 @@ class BlurTransformation constructor(
     }
 }
 
+/**
+ * Create a blur transform record
+ *
+ * @see com.github.panpf.sketch.core.common.test.transform.BlurTransformationTest.testBlurTransformed
+ */
 fun createBlurTransformed(
     radius: Int, hasAlphaBitmapBgColor: Int?, maskColor: Int?
 ) = "BlurTransformed($radius,$hasAlphaBitmapBgColor,$maskColor)"
 
+/**
+ * Check if the transformed string is a blur transformation
+ *
+ * @see com.github.panpf.sketch.core.common.test.transform.BlurTransformationTest.testBlurTransformed
+ */
 fun isBlurTransformed(transformed: String): Boolean =
     transformed.startsWith("BlurTransformed(")
 
+/**
+ * Get the blur transformation record from the transformed record list
+ *
+ * @see com.github.panpf.sketch.core.common.test.transform.BlurTransformationTest.testBlurTransformed
+ */
 fun List<String>.getBlurTransformed(): String? =
     find { isBlurTransformed(it) }
\ No newline at end of file
diff --git a/sketch-core/src/commonTest/kotlin/com/github/panpf/sketch/core/common/test/transform/BlurTransformationTest.kt b/sketch-core/src/commonTest/kotlin/com/github/panpf/sketch/core/common/test/transform/BlurTransformationTest.kt
new file mode 100644
index 0000000000..bdc534d5bb
--- /dev/null
+++ b/sketch-core/src/commonTest/kotlin/com/github/panpf/sketch/core/common/test/transform/BlurTransformationTest.kt
@@ -0,0 +1,211 @@
+/*
+ * Copyright (C) 2024 panpf <panpfpanpf@outlook.com>
+ *
+ * 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.
+ */
+
+package com.github.panpf.sketch.core.common.test.transform
+
+import com.github.panpf.sketch.images.ResourceImages
+import com.github.panpf.sketch.request.ImageRequest
+import com.github.panpf.sketch.size
+import com.github.panpf.sketch.test.singleton.getTestContextAndSketch
+import com.github.panpf.sketch.test.utils.corners
+import com.github.panpf.sketch.test.utils.decode
+import com.github.panpf.sketch.test.utils.hasAlpha
+import com.github.panpf.sketch.test.utils.toRequestContext
+import com.github.panpf.sketch.transform.BlurTransformation
+import com.github.panpf.sketch.transform.createBlurTransformed
+import com.github.panpf.sketch.transform.getBlurTransformed
+import com.github.panpf.sketch.util.Size
+import kotlinx.coroutines.test.runTest
+import org.jetbrains.skia.Color
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFailsWith
+import kotlin.test.assertFalse
+import kotlin.test.assertNotEquals
+import kotlin.test.assertNotSame
+import kotlin.test.assertNull
+import kotlin.test.assertTrue
+
+class BlurTransformationTest {
+
+    @Test
+    fun testConstructor() {
+        assertFailsWith(IllegalArgumentException::class) {
+            BlurTransformation(0)
+        }
+        assertFailsWith(IllegalArgumentException::class) {
+            BlurTransformation(101)
+        }
+        assertFailsWith(IllegalArgumentException::class) {
+            BlurTransformation(
+                hasAlphaBitmapBgColor = Color.withA(color = Color.BLACK, a = 244)
+            )
+        }
+        BlurTransformation(12).apply {
+            assertEquals(12, radius)
+            assertEquals(Color.BLACK, hasAlphaBitmapBgColor)
+            assertNull(maskColor)
+        }
+        BlurTransformation(20, hasAlphaBitmapBgColor = null, maskColor = Color.GREEN).apply {
+            assertEquals(20, radius)
+            assertNull(hasAlphaBitmapBgColor)
+            assertEquals(Color.GREEN, maskColor)
+        }
+    }
+
+    @Test
+    fun testKeyAndToString() {
+        BlurTransformation().apply {
+            assertEquals("BlurTransformation(15,${Color.BLACK},null)", key)
+            assertEquals("BlurTransformation(15,${Color.BLACK},null)", toString())
+        }
+        BlurTransformation(20, hasAlphaBitmapBgColor = null, maskColor = Color.GREEN).apply {
+            assertEquals("BlurTransformation(20,null,${Color.GREEN})", key)
+            assertEquals("BlurTransformation(20,null,${Color.GREEN})", toString())
+        }
+    }
+
+    @Test
+    fun testTransform() = runTest {
+        val (context, sketch) = getTestContextAndSketch()
+        val jpegRequest = ImageRequest(context, ResourceImages.jpeg.uri) {
+            size(Size.Origin)
+        }
+        val jpegRequestContext = jpegRequest.toRequestContext(sketch)
+
+        val inBitmap = jpegRequest.decode(sketch).image.apply {
+            assertFalse(this.hasAlpha())
+        }
+        inBitmap.apply {
+            assertNotEquals(
+                listOf(Color.TRANSPARENT, Color.TRANSPARENT, Color.TRANSPARENT, Color.TRANSPARENT),
+                this.corners()
+            )
+            assertEquals(
+                Size(1291, 1936),
+                this.size
+            )
+        }
+        val inBitmapCorners = inBitmap.corners()
+
+        val transformResult = BlurTransformation(
+            radius = 30,
+            maskColor = Color.withA(Color.BLUE, 80)
+        ).transform(sketch, jpegRequestContext, inBitmap)
+        transformResult.apply {
+            assertNotSame(inBitmap, image)
+            assertNotEquals(inBitmapCorners, image.corners())
+            assertEquals(Size(1291, 1936), image.size)
+            assertEquals(
+                expected = createBlurTransformed(
+                    radius = 30,
+                    hasAlphaBitmapBgColor = Color.BLACK,
+                    maskColor = Color.withA(Color.BLUE, 80)
+                ),
+                actual = transformed
+            )
+        }
+
+        // hasAlphaBitmapBgColor
+        val pngRequest = ImageRequest(context, ResourceImages.png.uri) {
+            size(Size.Origin)
+        }
+        val pngRequestContext = pngRequest.toRequestContext(sketch)
+        val hasAlphaBitmap1 = pngRequest.decode(sketch).image.apply {
+            assertTrue(this.hasAlpha())
+        }
+        val hasAlphaBitmapBlurred1 = BlurTransformation(30).transform(
+            sketch = sketch,
+            requestContext = pngRequestContext,
+            input = hasAlphaBitmap1
+        ).apply {
+            assertFalse(this.image.hasAlpha())
+        }.image
+
+        val hasAlphaBitmap2 = pngRequest.decode(sketch).image.apply {
+            assertTrue(this.hasAlpha())
+        }
+        val hasAlphaBitmapBlurred2 = BlurTransformation(30, hasAlphaBitmapBgColor = null)
+            .transform(
+                sketch,
+                pngRequestContext,
+                hasAlphaBitmap2
+            ).apply {
+                assertTrue(this.image.hasAlpha())
+            }.image
+        assertNotEquals(hasAlphaBitmapBlurred1.corners(), hasAlphaBitmapBlurred2.corners())
+    }
+
+    @Test
+    fun testEqualsAndHashCode() {
+        val element1 = BlurTransformation(20, null, null)
+        val element11 = BlurTransformation(20, null, null)
+        val element2 = BlurTransformation(10, Color.GREEN, null)
+        val element3 = BlurTransformation(20, Color.BLACK, Color.BLUE)
+        val element4 = BlurTransformation(20, Color.BLACK, Color.WHITE)
+
+        assertNotSame(element1, element11)
+        assertNotSame(element1, element2)
+        assertNotSame(element1, element3)
+        assertNotSame(element1, element4)
+        assertNotSame(element11, element2)
+        assertNotSame(element11, element3)
+        assertNotSame(element11, element4)
+        assertNotSame(element2, element3)
+        assertNotSame(element2, element4)
+        assertNotSame(element3, element4)
+
+        assertEquals(element1, element1)
+        assertEquals(element1, element11)
+        assertNotEquals(element1, element2)
+        assertNotEquals(element1, element3)
+        assertNotEquals(element1, element4)
+        assertNotEquals(element2, element11)
+        assertNotEquals(element2, element3)
+        assertNotEquals(element2, element4)
+        assertNotEquals(element3, element4)
+        assertNotEquals(element1, null as Any?)
+        assertNotEquals(element1, Any())
+
+        assertEquals(element1.hashCode(), element1.hashCode())
+        assertEquals(element1.hashCode(), element11.hashCode())
+        assertNotEquals(element1.hashCode(), element2.hashCode())
+        assertNotEquals(element2.hashCode(), element11.hashCode())
+        assertNotEquals(element2.hashCode(), element3.hashCode())
+    }
+
+    @Test
+    fun testBlurTransformed() {
+        assertEquals("BlurTransformed(1,null,null)", createBlurTransformed(1, null, null))
+        assertEquals("BlurTransformed(2,null,null)", createBlurTransformed(2, null, null))
+        assertEquals("BlurTransformed(4,null,null)", createBlurTransformed(4, null, null))
+        assertEquals("BlurTransformed(8,null,null)", createBlurTransformed(8, null, null))
+
+        assertEquals(null, listOf<String>().getBlurTransformed())
+        assertEquals(
+            "BlurTransformed(2,null,null)",
+            listOf(createBlurTransformed(2, null, null)).getBlurTransformed()
+        )
+        assertEquals(
+            "BlurTransformed(16,null,null)",
+            listOf(
+                "disruptive1",
+                createBlurTransformed(16, null, null),
+                "disruptive2"
+            ).getBlurTransformed()
+        )
+    }
+}
\ No newline at end of file
diff --git a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/BlurTransformationDesktopTest.kt b/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/BlurTransformationDesktopTest.kt
deleted file mode 100644
index e642ec8cee..0000000000
--- a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/BlurTransformationDesktopTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.desktop.test.transform
-
-class BlurTransformationDesktopTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/CircleCropTransformationDesktopTest.kt b/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/CircleCropTransformationDesktopTest.kt
deleted file mode 100644
index f6eacc98ef..0000000000
--- a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/CircleCropTransformationDesktopTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.desktop.test.transform
-
-class CircleCropTransformationDesktopTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/MaskTransformationDesktopTest.kt b/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/MaskTransformationDesktopTest.kt
deleted file mode 100644
index 28c2ceda3c..0000000000
--- a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/MaskTransformationDesktopTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.desktop.test.transform
-
-class MaskTransformationDesktopTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/RotateTransformationDesktopTest.kt b/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/RotateTransformationDesktopTest.kt
deleted file mode 100644
index 9c280643fd..0000000000
--- a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/RotateTransformationDesktopTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.desktop.test.transform
-
-class RotateTransformationDesktopTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/RoundedCornersTransformationDesktopTest.kt b/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/RoundedCornersTransformationDesktopTest.kt
deleted file mode 100644
index 72b19677dc..0000000000
--- a/sketch-core/src/desktopTest/kotlin/com/github/panpf/sketch/core/desktop/test/transform/RoundedCornersTransformationDesktopTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.desktop.test.transform
-
-class RoundedCornersTransformationDesktopTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/BlurTransformationJsCommonTest.kt b/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/BlurTransformationJsCommonTest.kt
deleted file mode 100644
index 9c3d1332fa..0000000000
--- a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/BlurTransformationJsCommonTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.jscommon.test.transform
-
-class BlurTransformationJsCommonTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/CircleCropTransformationJsCommonTest.kt b/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/CircleCropTransformationJsCommonTest.kt
deleted file mode 100644
index ad93f0786d..0000000000
--- a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/CircleCropTransformationJsCommonTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.jscommon.test.transform
-
-class CircleCropTransformationJsCommonTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/MaskTransformationJsCommonTest.kt b/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/MaskTransformationJsCommonTest.kt
deleted file mode 100644
index 3c6a2243cc..0000000000
--- a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/MaskTransformationJsCommonTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.jscommon.test.transform
-
-class MaskTransformationJsCommonTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/RotateTransformationJsCommonTest.kt b/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/RotateTransformationJsCommonTest.kt
deleted file mode 100644
index b49ae7b5d4..0000000000
--- a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/RotateTransformationJsCommonTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.jscommon.test.transform
-
-class RotateTransformationJsCommonTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/RoundedCornersTransformationJsCommonTest.kt b/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/RoundedCornersTransformationJsCommonTest.kt
deleted file mode 100644
index 02c7e7b027..0000000000
--- a/sketch-core/src/jsCommonTest/kotlin/com/github/panpf/sketch/core/jscommon/test/transform/RoundedCornersTransformationJsCommonTest.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package com.github.panpf.sketch.core.jscommon.test.transform
-
-class RoundedCornersTransformationJsCommonTest {
-    // TODO test
-}
\ No newline at end of file
diff --git a/sketch-core/src/nonAndroidMain/kotlin/com/github/panpf/sketch/util/skia_bitmaps.kt b/sketch-core/src/nonAndroidMain/kotlin/com/github/panpf/sketch/util/skia_bitmaps.kt
index 270c8d5d65..b08bfe7e63 100644
--- a/sketch-core/src/nonAndroidMain/kotlin/com/github/panpf/sketch/util/skia_bitmaps.kt
+++ b/sketch-core/src/nonAndroidMain/kotlin/com/github/panpf/sketch/util/skia_bitmaps.kt
@@ -27,6 +27,7 @@ import org.jetbrains.skia.Canvas
 import org.jetbrains.skia.Color
 import org.jetbrains.skia.ColorType
 import org.jetbrains.skia.Image
+import org.jetbrains.skia.ImageInfo
 import org.jetbrains.skia.Paint
 import org.jetbrains.skia.RRect
 import kotlin.math.ceil
@@ -41,7 +42,7 @@ internal fun SkiaBitmap.copied(): SkiaBitmap {
     return outBitmap
 }
 
-internal fun SkiaBitmap.hasAlpha(): Boolean {
+fun SkiaBitmap.hasAlpha(): Boolean {
     val height = this.height
     val width = this.width
     var hasAlpha = false
@@ -258,6 +259,19 @@ internal fun SkiaBitmap.scaled(scaleFactor: Float): SkiaBitmap {
     return outBitmap
 }
 
+/**
+ * Returns the Color at the specified location.
+ */
+fun SkiaBitmap.getPixel(x: Int, y: Int): Int {
+    val bitmap = this
+    val stride = 1
+    val bytesPerPixel = 4
+    val colorInfo = bitmap.colorInfo
+    val imageInfo = ImageInfo(colorInfo, 1, 1)
+    val bytes = bitmap.readPixels(imageInfo, stride * bytesPerPixel, x, y)!!
+    val intColorPixels = convertToIntColorPixels(bytes, colorInfo.colorType)
+    return intColorPixels.first()
+}
 
 private fun convertToIntColorPixels(byteArray: ByteArray, colorType: ColorType): IntArray {
     return when (colorType) {