在Android应用中更改位图分辨率

时间:2012-03-31 18:07:17

标签: android bitmap resolution

我正在编写一个使用手机相机拍照的应用程序,然后在我的应用程序中使用它。问题是,应用耗尽内存,这可能是因为位图的高分辨率。有没有办法让位图保持相同的大小,但会降低分辨率?

谢谢!

3 个答案:

答案 0 :(得分:4)

您可以设置其宽度和高度

Bitmap bm = ShrinkBitmap(imagefile, 150, 150);

致电功能

Bitmap ShrinkBitmap(String file, int width, int height){

 BitmapFactory.Options bmpFactoryOptions = new BitmapFactory.Options();
    bmpFactoryOptions.inJustDecodeBounds = true;
    Bitmap bitmap = BitmapFactory.decodeFile(file, bmpFactoryOptions);

    int heightRatio = (int)Math.ceil(bmpFactoryOptions.outHeight/(float)height);
    int widthRatio = (int)Math.ceil(bmpFactoryOptions.outWidth/(float)width);

    if (heightRatio > 1 || widthRatio > 1)
    {
     if (heightRatio > widthRatio)
     {
      bmpFactoryOptions.inSampleSize = heightRatio;
     } else {
      bmpFactoryOptions.inSampleSize = widthRatio; 
     }
    }

    bmpFactoryOptions.inJustDecodeBounds = false;
    bitmap = BitmapFactory.decodeFile(file, bmpFactoryOptions);
 return bitmap;
}

}

这是另外两个可能帮助您的链接。 Link 1& Link 2

答案 1 :(得分:4)

来自jeet.chanchawat'答案:https://stackoverflow.com/a/10703256/3027225

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

答案 2 :(得分:2)

这可以在创建位图时使用Options.inSampleSize来完成