我有一个位图采取的Base64字符串从我的远程数据库，(encodedImage是字符串表示图像与Base64):
profileImage = (ImageView)findViewById(R.id.profileImage);
byte[] imageAsBytes=null;
try {
imageAsBytes = Base64.decode(encodedImage.getBytes());
} catch (IOException e) {e.printStackTrace();}
profileImage.setImageBitmap(
BitmapFactory.decodeByteArray(imageAsBytes, 0, imageAsBytes.length)
);
profileImage是我的ImageView
但在显示在布局的ImageView中之前，我需要调整图像的大小。我得把它调整到120x120。
有人能告诉我调整大小的代码吗?
我发现的例子不能应用于base64字符串获得位图。
当前回答
/**
* Kotlin method for Bitmap scaling
* @param bitmap the bitmap to be scaled
* @param pixel the target pixel size
* @param width the width
* @param height the height
* @param max the max(height, width)
* @return the scaled bitmap
*/
fun scaleBitmap(bitmap:Bitmap, pixel:Float, width:Int, height:Int, max:Int):Bitmap {
val scale = px / max
val h = Math.round(scale * height)
val w = Math.round(scale * width)
return Bitmap.createScaledBitmap(bitmap, w, h, true)
}
其他回答
缩放位图的目标最大大小和宽度，同时保持纵横比:
int maxHeight = 2000;
int maxWidth = 2000;
float scale = Math.min(((float)maxHeight / bitmap.getWidth()), ((float)maxWidth / bitmap.getHeight()));
Matrix matrix = new Matrix();
matrix.postScale(scale, scale);
bitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
位图调整基于任何显示大小
public Bitmap bitmapResize(Bitmap imageBitmap) {
Bitmap bitmap = imageBitmap;
float heightbmp = bitmap.getHeight();
float widthbmp = bitmap.getWidth();
// Get Screen width
DisplayMetrics displaymetrics = new DisplayMetrics();
this.getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
float height = displaymetrics.heightPixels / 3;
float width = displaymetrics.widthPixels / 3;
int convertHeight = (int) hight, convertWidth = (int) width;
// higher
if (heightbmp > height) {
convertHeight = (int) height - 20;
bitmap = Bitmap.createScaledBitmap(bitmap, convertWidth,
convertHighet, true);
}
// wider
if (widthbmp > width) {
convertWidth = (int) width - 20;
bitmap = Bitmap.createScaledBitmap(bitmap, convertWidth,
convertHeight, true);
}
return bitmap;
}
apply Matrix.ScaleToFit.CENTER)获取一个新的位图保持纵横比。
public static Bitmap getScaledwonBitmap(Bitmap srcBmp, int deisredWidth, int desiredHeight) {
Matrix matrix = new Matrix();
matrix.setRectToRect(new RectF(0, 0, srcBmp.getWidth(), srcBmp.getHeight()),
new RectF(0, 0, deisredWidth, desiredHeight),
Matrix.ScaleToFit.CENTER);
return Bitmap.createBitmap(srcBmp, 0, 0, srcBmp.getWidth(), srcBmp.getHeight(), matrix, true);
}
Try this kotlin code for resize....Where Max size any size you
want
fun getResizedBitmap(image: Bitmap?, maxSize: Int): Bitmap {
var width = image!!.width
var height = image.height
val bitmapRatio = width.toFloat() / height.toFloat()
if (bitmapRatio > 0) {
width = maxSize
height = (width / bitmapRatio).toInt()
} else {
height = maxSize
width = (height * bitmapRatio).toInt()
}
return Bitmap.createScaledBitmap(image, width, height, true)
}
保持纵横比，
public Bitmap resizeBitmap(Bitmap source, int width,int height) {
if(source.getHeight() == height && source.getWidth() == width) return source;
int maxLength=Math.min(width,height);
try {
source=source.copy(source.getConfig(),true);
if (source.getHeight() <= source.getWidth()) {
if (source.getHeight() <= maxLength) { // if image already smaller than the required height
return source;
}
double aspectRatio = (double) source.getWidth() / (double) source.getHeight();
int targetWidth = (int) (maxLength * aspectRatio);
return Bitmap.createScaledBitmap(source, targetWidth, maxLength, false);
} else {
if (source.getWidth() <= maxLength) { // if image already smaller than the required height
return source;
}
double aspectRatio = ((double) source.getHeight()) / ((double) source.getWidth());
int targetHeight = (int) (maxLength * aspectRatio);
return Bitmap.createScaledBitmap(source, maxLength, targetHeight, false);
}
}
catch (Exception e)
{
return source;
}
}
