YUV NV21字节阵列 - ＆gt; rgb数组 - ＆gt; renderscript过滤器 - ＆gt; YUV NV21字节数组

Question

我希望从相机预览中获取YUV格式，将其更改为rgb字节数组，对其应用Renderscript滤镜（例如灰度级）并将其还原为YUV字节数组。

我已经介绍了第一部分，但我找不到将rgb字节数组转换回YUV的有效方法。

outputBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
// Create an allocation that corresponds to the outputBitmap
allocationOut = Allocation.createFromBitmap(renderScript, outputBitmap);

// allocationIn matches the allocationOut
allocationIn = Allocation.createTyped(renderScript, allocationOut.getType(),
android.renderscript.Allocation.USAGE_SCRIPT);

greyScaleMatrix = ScriptIntrinsicColorMatrix.create(renderScript, allocationOut.getElement());
greyScaleMatrix.setGreyscale();

Type.Builder typeYUV = new Type.Builder(renderScript,
        Element.createPixel(renderScript, Element.DataType.UNSIGNED_8, Element.DataKind.PIXEL_YUV));
typeYUV.setYuvFormat(ImageFormat.NV21);

// allocation for the YUV input from the camera
allocationYUV = Allocation.createTyped(renderScript, typeYUV.setX(width).setY(height).create(),
    android.renderscript.Allocation.USAGE_SCRIPT);
allocationYUV.copyFrom(dataIn);

// Create the instance for the YuvToRGB
scriptIntrinsicYuvToRGB = ScriptIntrinsicYuvToRGB.create(renderScript, Element.U8_4(renderScript));

scriptIntrinsicYuvToRGB.setInput(allocationYUV);
scriptIntrinsicYuvToRGB.forEach(allocationIn);

// Apply Grayscale
greyScaleMatrix.forEach(allocationIn, allocationOut);

allocationOut.copyTo(outputBitmap);

现在它输出到Bitmap，但理想情况下会有一个与ScriptIntrinsicYuvToRGB相反的ScriptIntrinsicRGBToYuv renderscript对象/脚本。

感谢您的帮助！