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我有Android位图缩放和采样混淆这里可能有两个代码缩放和另一个采样任何人都可以帮助我确定这两个代码的工作和它们之间的主要区别是什么。
缩放和位图采样有什么区别？
缩放：
public static Bitmap getScaleBitmap(Bitmap bitmap, int newWidth, int newHeight) {
int width = bitmap.getWidth();
int height = bitmap.getHeight();
float scaleWidth = ((float) newWidth)/width;
float scaleHeight = ((float) newHeight)/height;
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
return Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, false);
}
采样：
mImageView.setImageBitmap(decodeSampledBitmapFromResource(getResources(),R.id.myimage, 100, 100));
public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
int reqWidth, int reqHeight) {
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeResource(res, resId, options);
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
options.inJustDecodeBounds = false;
return BitmapFactory.decodeResource(res, resId, options);
}
public static int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
final int halfHeight = height/2;
final int halfWidth = width/2;
while ((halfHeight/inSampleSize) >= reqHeight
&& (halfWidth/inSampleSize) >= reqWidth) {
inSampleSize *= 2;
}
}
return inSampleSize;
}
这里既有代码执行图像尺寸调整，但不同的方式，使我怎么能辨别哪一个是好的和简单。