Create BlurUtils.kt

app/src/main/java/me/bzcoder/webview/utils/BlurUtils.kt

@@ -0,0 +1,230 @@
+package me.bzcoder.easyglide.util
+
+import android.content.Context
+import android.graphics.Bitmap
+import android.os.Build
+import android.renderscript.Allocation
+import android.renderscript.Element
+import android.renderscript.RenderScript
+import android.renderscript.ScriptIntrinsicBlur
+import androidx.annotation.RequiresApi
+
+/**
+ * @author sunfusheng on 2018/6/25.
+ */
+object BlurUtils {
+    fun rsBlur(context: Context?, toTransform: Bitmap, radius: Int): Bitmap {
+        val renderScript = RenderScript.create(context)
+        val input = Allocation.createFromBitmap(renderScript, toTransform)
+        val output = Allocation.createTyped(renderScript, input.type)
+        val scriptIntrinsicBlur = ScriptIntrinsicBlur.create(renderScript, Element.U8_4(renderScript))
+        scriptIntrinsicBlur.setInput(input)
+        scriptIntrinsicBlur.setRadius(radius.toFloat())
+        scriptIntrinsicBlur.forEach(output)
+        output.copyTo(toTransform)
+        renderScript.destroy()
+        return toTransform
+    }
+
+    fun blur(toTransform: Bitmap, radius: Int): Bitmap? {
+        if (radius < 1) {
+            return null
+        }
+        val w = toTransform.width
+        val h = toTransform.height
+        val pix = IntArray(w * h)
+        toTransform.getPixels(pix, 0, w, 0, 0, w, h)
+        val wm = w - 1
+        val hm = h - 1
+        val wh = w * h
+        val div = radius + radius + 1
+        val r = IntArray(wh)
+        val g = IntArray(wh)
+        val b = IntArray(wh)
+        var rsum: Int
+        var gsum: Int
+        var bsum: Int
+        var x: Int
+        var y: Int
+        var i: Int
+        var p: Int
+        var yp: Int
+        var yi: Int
+        var yw: Int
+        val vmin = IntArray(Math.max(w, h))
+        var divsum = div + 1 shr 1
+        divsum *= divsum
+        val dv = IntArray(256 * divsum)
+        i = 0
+        while (i < 256 * divsum) {
+            dv[i] = i / divsum
+            i++
+        }
+        yi = 0
+        yw = yi
+        val stack = Array(div) { IntArray(3) }
+        var stackpointer: Int
+        var stackstart: Int
+        var sir: IntArray
+        var rbs: Int
+        val r1 = radius + 1
+        var routsum: Int
+        var goutsum: Int
+        var boutsum: Int
+        var rinsum: Int
+        var ginsum: Int
+        var binsum: Int
+        y = 0
+        while (y < h) {
+            bsum = 0
+            gsum = bsum
+            rsum = gsum
+            boutsum = rsum
+            goutsum = boutsum
+            routsum = goutsum
+            binsum = routsum
+            ginsum = binsum
+            rinsum = ginsum
+            i = -radius
+            while (i <= radius) {
+                p = pix[yi + Math.min(wm, Math.max(i, 0))]
+                sir = stack[i + radius]
+                sir[0] = p and 0xff0000 shr 16
+                sir[1] = p and 0x00ff00 shr 8
+                sir[2] = p and 0x0000ff
+                rbs = r1 - Math.abs(i)
+                rsum += sir[0] * rbs
+                gsum += sir[1] * rbs
+                bsum += sir[2] * rbs
+                if (i > 0) {
+                    rinsum += sir[0]
+                    ginsum += sir[1]
+                    binsum += sir[2]
+                } else {
+                    routsum += sir[0]
+                    goutsum += sir[1]
+                    boutsum += sir[2]
+                }
+                i++
+            }
+            stackpointer = radius
+            x = 0
+            while (x < w) {
+                r[yi] = dv[rsum]
+                g[yi] = dv[gsum]
+                b[yi] = dv[bsum]
+                rsum -= routsum
+                gsum -= goutsum
+                bsum -= boutsum
+                stackstart = stackpointer - radius + div
+                sir = stack[stackstart % div]
+                routsum -= sir[0]
+                goutsum -= sir[1]
+                boutsum -= sir[2]
+                if (y == 0) {
+                    vmin[x] = Math.min(x + radius + 1, wm)
+                }
+                p = pix[yw + vmin[x]]
+                sir[0] = p and 0xff0000 shr 16
+                sir[1] = p and 0x00ff00 shr 8
+                sir[2] = p and 0x0000ff
+                rinsum += sir[0]
+                ginsum += sir[1]
+                binsum += sir[2]
+                rsum += rinsum
+                gsum += ginsum
+                bsum += binsum
+                stackpointer = (stackpointer + 1) % div
+                sir = stack[stackpointer % div]
+                routsum += sir[0]
+                goutsum += sir[1]
+                boutsum += sir[2]
+                rinsum -= sir[0]
+                ginsum -= sir[1]
+                binsum -= sir[2]
+                yi++
+                x++
+            }
+            yw += w
+            y++
+        }
+        x = 0
+        while (x < w) {
+            bsum = 0
+            gsum = bsum
+            rsum = gsum
+            boutsum = rsum
+            goutsum = boutsum
+            routsum = goutsum
+            binsum = routsum
+            ginsum = binsum
+            rinsum = ginsum
+            yp = -radius * w
+            i = -radius
+            while (i <= radius) {
+                yi = Math.max(0, yp) + x
+                sir = stack[i + radius]
+                sir[0] = r[yi]
+                sir[1] = g[yi]
+                sir[2] = b[yi]
+                rbs = r1 - Math.abs(i)
+                rsum += r[yi] * rbs
+                gsum += g[yi] * rbs
+                bsum += b[yi] * rbs
+                if (i > 0) {
+                    rinsum += sir[0]
+                    ginsum += sir[1]
+                    binsum += sir[2]
+                } else {
+                    routsum += sir[0]
+                    goutsum += sir[1]
+                    boutsum += sir[2]
+                }
+                if (i < hm) {
+                    yp += w
+                }
+                i++
+            }
+            yi = x
+            stackpointer = radius
+            y = 0
+            while (y < h) {
+                pix[yi] = -0x1000000 and pix[yi] or (dv[rsum] shl 16) or (dv[gsum] shl 8) or dv[bsum]
+                rsum -= routsum
+                gsum -= goutsum
+                bsum -= boutsum
+                stackstart = stackpointer - radius + div
+                sir = stack[stackstart % div]
+                routsum -= sir[0]
+                goutsum -= sir[1]
+                boutsum -= sir[2]
+                if (x == 0) {
+                    vmin[y] = Math.min(y + r1, hm) * w
+                }
+                p = x + vmin[y]
+                sir[0] = r[p]
+                sir[1] = g[p]
+                sir[2] = b[p]
+                rinsum += sir[0]
+                ginsum += sir[1]
+                binsum += sir[2]
+                rsum += rinsum
+                gsum += ginsum
+                bsum += binsum
+                stackpointer = (stackpointer + 1) % div
+                sir = stack[stackpointer]
+                routsum += sir[0]
+                goutsum += sir[1]
+                boutsum += sir[2]
+                rinsum -= sir[0]
+                ginsum -= sir[1]
+                binsum -= sir[2]
+                yi += w
+                y++
+            }
+            x++
+        }
+        toTransform.setPixels(pix, 0, w, 0, 0, w, h)
+        return toTransform
+    }
+}