我试图在两幅图像上应用混合滤镜(在这种情况下为HardLight)。基础Android库不支持HardLight,因此,我正在手动处理每个像素。第一轮运行正常,但速度不及恒星。从基本500x500图像和500x500滤镜生成500x500图像的过程时间过长。这段代码也用于生成缩略图(72x72),它也是应用程序核心的组成部分。我很乐意提供一些关于如何加快速度的建议和/或提示。在Android位图上优化每像素混合
如果通过假设任何一个图像都没有alpha值就可以获得巨大收益,那很好。 注意:BlendMode和alpha是在示例中没有使用的值(BlendMode将选择混合类型,在这种情况下,我硬编码HardLight)。
public Bitmap blendedBitmap(Bitmap source, Bitmap layer, BlendMode blendMode, float alpha) {
Bitmap base = source.copy(Config.ARGB_8888, true);
Bitmap blend = layer.copy(Config.ARGB_8888, false);
IntBuffer buffBase = IntBuffer.allocate(base.getWidth() * base.getHeight());
base.copyPixelsToBuffer(buffBase);
buffBase.rewind();
IntBuffer buffBlend = IntBuffer.allocate(blend.getWidth() * blend.getHeight());
blend.copyPixelsToBuffer(buffBlend);
buffBlend.rewind();
IntBuffer buffOut = IntBuffer.allocate(base.getWidth() * base.getHeight());
buffOut.rewind();
while (buffOut.position() < buffOut.limit()) {
int filterInt = buffBlend.get();
int srcInt = buffBase.get();
int redValueFilter = Color.red(filterInt);
int greenValueFilter = Color.green(filterInt);
int blueValueFilter = Color.blue(filterInt);
int redValueSrc = Color.red(srcInt);
int greenValueSrc = Color.green(srcInt);
int blueValueSrc = Color.blue(srcInt);
int redValueFinal = hardlight(redValueFilter, redValueSrc);
int greenValueFinal = hardlight(greenValueFilter, greenValueSrc);
int blueValueFinal = hardlight(blueValueFilter, blueValueSrc);
int pixel = Color.argb(255, redValueFinal, greenValueFinal, blueValueFinal);
buffOut.put(pixel);
}
buffOut.rewind();
base.copyPixelsFromBuffer(buffOut);
blend.recycle();
return base;
}
private int hardlight(int in1, int in2) {
float image = (float)in2;
float mask = (float)in1;
return ((int)((image < 128) ? (2 * mask * image/255):(255 - 2 * (255 - mask) * (255 - image)/255)));
}
嗨,你能帮助我如何在这个函数中使用alpha吗? – 2012-02-21 00:16:59