Question

我有非常大的位图图像。我的来源

BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(new FileInputStream(f), null, o);

            // The new size we want to scale to
            final int REQUIRED_WIDTH = 1000;
            final int REQUIRED_HIGHT = 500;
            // Find the correct scale value. It should be the power of 2.
            int scale = 1;
            while (o.outWidth / scale / 2 >= REQUIRED_WIDTH
                    && o.outHeight / scale / 2 >= REQUIRED_HIGHT)
                scale *= 2;

            // Decode with inSampleSize
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);

我想正确调整图片大小，我需要将图片调整为最大可用尺寸

例如

我下载的图片尺寸为4000x4000像素，手机尺寸为2000x1500像素我需要anderstend 尺寸如何支持我的手机？然后我将图像调整为2000x1500（例如）

Answer 1

您可以将位图的大小调整为最大可用大小：

public void onClick() //for example 
{
/*
Getting screen diemesions
*/
WindowManager w = getWindowManager();
        Display d = w.getDefaultDisplay();
        int width = d.getWidth();
        int height = d.getHeight(); 
// "bigging" bitmap
Bitmap nowa = getResizedBitmap(yourbitmap, width, height);
}

public Bitmap getResizedBitmap(Bitmap bm, int newHeight, int newWidth) {

int width = bm.getWidth();

int height = bm.getHeight();

float scaleWidth = ((float) newWidth) / width;

float scaleHeight = ((float) newHeight) / height;

// create a matrix for the manipulation

Matrix matrix = new Matrix();

// resize the bit map

matrix.postScale(scaleWidth, scaleHeight);

// recreate the new Bitmap

Bitmap resizedBitmap = Bitmap.createBitmap(bm, 0, 0, width, height, matrix, false);

return resizedBitmap;

}

我希望我帮助

Answer 2

不太完美，但这是我的解决方案，

fun setScaleImageWithConstraint（bitmap：Bitmap）：位图{

        val maxWidth = 500 //max Height Constraint
        val maxHeight = 500 //max Width Constraint

        var width = bitmap.width
        var height = bitmap.height

        if (width > maxWidth || height > maxHeight) {
            //If Image is still Large than allowed W/H Half the Size
            val quarterWidth = ((width / 2).toFloat() + (width / 3).toFloat()).toInt()
            val quarterHeight = ((height / 2).toFloat() + (height / 3).toFloat()).toInt()
            val scaledBitmap = Bitmap.createScaledBitmap(bitmap, quarterWidth, quarterHeight, false)
            //Recursive Call to Resize and return Resized One
            return setScaleImageWithConstraint(scaledBitmap)
        } else {
            //This will be executed when Image is not violating the Constraints
            return bitmap
        }
    }

递归减少位图的四分之一大小，直到达到允许的高度和高度。

如何将位图大小调整为最大可用大小？

2 个答案: