android 使用 Renderscript 模糊的问题

Question

我正在使用以下代码为我的 imageview 构建模糊背景。

public class BlurBuilder {
    private static final float BITMAP_SCALE = 0.2f;
    private static final float BLUR_RADIUS = 25f;

    public static Bitmap blur(Context context, Bitmap image) {
        int width = Math.round(image.getWidth() * BITMAP_SCALE);
        int height = Math.round(image.getHeight() * BITMAP_SCALE);

        Bitmap inputBitmap = Bitmap.createScaledBitmap(image, width, height, false);
        Bitmap outputBitmap = Bitmap.createBitmap(inputBitmap);

        RenderScript rs = RenderScript.create(context);
        ScriptIntrinsicBlur theIntrinsic = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));
        Allocation tmpIn = Allocation.createFromBitmap(rs, inputBitmap);
        Allocation tmpOut = Allocation.createFromBitmap(rs, outputBitmap);
        theIntrinsic.setRadius(BLUR_RADIUS);
        theIntrinsic.setInput(tmpIn);
        theIntrinsic.forEach(tmpOut);
        tmpOut.copyTo(outputBitmap);

        return outputBitmap;
    }
}

Blur 在大多数情况下构建良好，但随着时间的推移会变得糟糕，最终我的应用程序崩溃而没有任何崩溃日志。在模拟器运行上，经过严格测试后，我看到以下错误：

09-01 15:05:03.230 4624-9758/? E/RenderScript: rsAssert failed: ret == bytes || mShutdown, in frameworks/rs/rsFifoSocket.cpp at 83
09-01 15:05:03.238 4624-9781/? E/RenderScript: rsAssert failed: ret == bytes || mShutdown, in frameworks/rs/rsFifoSocket.cpp at 83
09-01 15:05:03.242 4624-10128/? E/RenderScript: rsAssert failed: ret == bytes || mShutdown, in frameworks/rs/rsFifoSocket.cpp at 83
09-01 15:05:03.242 4624-9610/? E/RenderScript: rsAssert failed: ret == bytes || mShutdown, in frameworks/rs/rsFifoSocket.cpp at 83
09-01 15:05:03.242 4624-9781/? E/RenderScript: rsAssert failed: ret == bytes || mShutdown, in frameworks/rs/rsFifoSocket.cpp at 83
09-01 15:05:03.250 4624-9767/? E/RenderScript: rsAssert failed: ret == bytes || mShutdown, in frameworks/rs/rsFifoSocket.cpp at 83
09-01 15:05:03.254 4624-9758/? E/RenderScript: rsAssert failed: ret == bytes || mShutdown, in frameworks/rs/rsFifoSocket.cpp at 83
... (same error - many more times and then crash)

我有以下这方面的疑问：

我正在为渲染脚本使用以下 gradle 配置：

compileSdkVersion 23 buildToolsVersion "23.0.3"

默认配置{ 应用程序 ID "package " minSdkVersion 19 targetSdk版本 23 multiDexEnabled 真 renderscriptTargetApi 19 renderscriptSupportModeEnabled 真 }

renderscript 库的推荐版本是什么？我应该从 android.support.v8.renderscript.Allocation orandroid.renderscript` 包中导入依赖项吗？

不使用 renderscript 库可以实现模糊效果吗？

Answer 1

经过一天多的时间，我明白了以下几点：

应用程序崩溃，因为 Renderscript 库抛出异常。这通常发生在处理能力低的设备中。此异常不是 Java 异常，无法捕获。

使用以下代码作为另一种方式来发出模糊（不使用 renderscript 库）：

public static Bitmap fastblur(Bitmap sentBitmap) {

int radius = (int) BLUR_RADIUS;

int width = Math.round(sentBitmap.getWidth() * BITMAP_SCALE);
int height = Math.round(sentBitmap.getHeight() * BITMAP_SCALE);
sentBitmap = Bitmap.createScaledBitmap(sentBitmap, width, height, false);

Bitmap bitmap = sentBitmap.copy(sentBitmap.getConfig(), true);

if (radius < 1) {
    return (null);
}

int w = bitmap.getWidth();
int h = bitmap.getHeight();

int[] pix = new int[w * h];
Log.e("pix", w + " " + h + " " + pix.length);
bitmap.getPixels(pix, 0, w, 0, 0, w, h);

int wm = w - 1;
int hm = h - 1;
int wh = w * h;
int div = radius + radius + 1;

int r[] = new int[wh];
int g[] = new int[wh];
int b[] = new int[wh];
int rsum, gsum, bsum, x, y, i, p, yp, yi, yw;
int vmin[] = new int[Math.max(w, h)];

int divsum = (div + 1) >> 1;
divsum *= divsum;
int dv[] = new int[256 * divsum];
for (i = 0; i < 256 * divsum; i++) {
    dv[i] = (i / divsum);
}

yw = yi = 0;

int[][] stack = new int[div][3];
int stackpointer;
int stackstart;
int[] sir;
int rbs;
int r1 = radius + 1;
int routsum, goutsum, boutsum;
int rinsum, ginsum, binsum;

for (y = 0; y < h; y++) {
    rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
    for (i = -radius; i <= radius; i++) {
        p = pix[yi + Math.min(wm, Math.max(i, 0))];
        sir = stack[i + radius];
        sir[0] = (p & 0xff0000) >> 16;
        sir[1] = (p & 0x00ff00) >> 8;
        sir[2] = (p & 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];
        }
    }
    stackpointer = radius;

    for (x = 0; x < w; x++) {

        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 & 0xff0000) >> 16;
        sir[1] = (p & 0x00ff00) >> 8;
        sir[2] = (p & 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++;
    }
    yw += w;
}
for (x = 0; x < w; x++) {
    rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
    yp = -radius * w;
    for (i = -radius; i <= radius; i++) {
        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;
        }
    }
    yi = x;
    stackpointer = radius;
    for (y = 0; y < h; y++) {
        // Preserve alpha channel: ( 0xff000000 & pix[yi] )
        pix[yi] = ( 0xff000000 & pix[yi] ) | ( dv[rsum] << 16 ) | ( dv[gsum] << 8 ) | 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;
    }
}

Log.e("pix", w + " " + h + " " + pix.length);
bitmap.setPixels(pix, 0, w, 0, 0, w, h);

return (bitmap);
}

android 使用 Renderscript 模糊的问题

Issues with android blur using Renderscript

android

renderscript

android-renderscript