我正在寻找添加模糊动画ImageView，但有设定的持续时间。例如，我希望图像随着时间的推移而变得模糊。
我已经有了模糊图像的方法，但我需要的是让它在 2 秒内从模糊变为不模糊。
有人可以帮我吗？
编辑：这是我目前模糊图像的方法。
public Bitmap blur(Bitmap sentBitmap, int radius) {
// Stack Blur Algorithm by Mario Klingemann <[email protected]>
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 上的模糊效果总是很困难。本质上，您必须在外观和性能之间做出决定。模糊看起来越好，所需的时间就越长，如果模糊本身不是瞬时的，那么您就无法真正为模糊设置动画。
你原来的模糊算法产生了非常好的结果，但正因为如此，它也非常慢，使得模糊动画不可能。为了演示如何有效地模糊该图像，我通过缩小位图创建了一个简单的模糊动画：
public class BlurAnimation extends Animation {
private final ImageView imageView;
private final Bitmap bitmap;
private final float startValue;
private final float stopValue;
private final float difValue;
private BlurAnimation(ImageView imageView, Bitmap bitmap, int startValue, int stopValue) {
this.imageView = imageView;
this.bitmap = bitmap;
this.startValue = startValue;
this.stopValue = stopValue;
this.difValue = stopValue - startValue;
}
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
super.applyTransformation(interpolatedTime, t);
int current = (int)(this.difValue * interpolatedTime + this.startValue + 0.5f);
Bitmap blurred = quickBlur(this.bitmap, current);
this.imageView.setImageBitmap(blurred);
}
public Bitmap quickBlur(Bitmap bitmap, int factor) {
if(factor <= 0) {
return Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888);
}
return Bitmap.createScaledBitmap(bitmap, bitmap.getWidth() / factor, bitmap.getHeight() / factor, true);
}
}
这工作得很好（尽管仍然有一些滞后），但结果无法与你的模糊算法进行比较，它看起来很糟糕：
所以你看，在模糊图像时很难将性能和美观结合起来，但首先有一些选择RenderScript. RenderScript速度非常快，并且有一个内置的高斯模糊滤镜。我从未使用过它，但据我所知，它可能可以解决您的问题。
您还可以尝试加载已经缩小的图像版本，这将产生与上面的 gif 相同的效果，但速度会更快。缺点是在Animation又是有问题的，但如果您只需要模糊的图像并且您并不真正关心质量，那么您应该选择此选项。
您可以找到有关以下内容的更多信息RenderScript和其他快速模糊选项在这个答案中