1

我在 SD 卡上有 3 张图片（1 张 jpg 和 2 张 gif）。我想减少它们以节省内存。调整大小后 JPG 调整大小成功，但 GIF 图像具有原始大小。查看代码和日志：

public class BitmapHelper 
{
    private static int calculateInSampleSize(BitmapFactory.Options options, int imgHeigth, int imgWidth)
    {
        int inSampleSize = 1;

    if(imgHeigth > 80 || imgWidth > 120)
    {
        final int heightRatio = Math.round((float) imgHeigth / 80);
        final int widthRatio = Math.round((float) imgWidth / 120);

        if(heightRatio < widthRatio)
            return heightRatio;
        if(heightRatio > widthRatio)
            return widthRatio;
        if(heightRatio == widthRatio)
            return heightRatio;

    }

    return inSampleSize;
}

public Bitmap decodeBitmapFromFile(String imageUrl, Resources res)
{
    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(imageUrl, options);
    if(options.outMimeType != null)
    {
        options.inSampleSize = calculateInSampleSize(options, options.outHeight, options.outWidth);
        options.inJustDecodeBounds = false;
        Bitmap bmp = BitmapFactory.decodeFile(imageUrl, options);
        Log.d("Debugger", "Height: " + options.outHeight + "; Width: " + options.outWidth);
        return bmp;

    }
    else
    {
        options.inSampleSize = 2;
        options.inJustDecodeBounds = false;
        return BitmapFactory.decodeResource(res, R.drawable.play, options);
    }           
}
}

日志：

Height: 97; Width: 175
Height: 324; Width: 550
Height: 97; Width: 175
Height: 226; Width: 400
Height: 97; Width: 175
Height: 324; Width: 550
Height: 226; Width: 400

97x175 - JPEG - (Original size: 388x698)
324x550 - GIF - original size
226x400 - GIF - original size

怎么了？非常感谢。

4

2 回答 2

0

试试这个代码来重新调整它的大小：

Display display = getWindow().getWindowManager().getDefaultDisplay();                    
                int hsize= (int) ((int)display.getHeight()-(display.getHeight()*(0.50)));
                int wsize= (int) ((int)display.getWidth()-(display.getWidth()*0.25));   

             Bitmap originalImage=decodeSampledBitmapFromResource(getResources(),imageId,wsize,hsize);             
             ImageView imageView = new ImageView(mContext);
             imageView.setImageBitmap(scaleBitmap(originalImage));
             imageView.setLayoutParams(new CoverFlow.LayoutParams(wsize,hsize));
             imageView.setScaleType(ScaleType.MATRIX);

public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId, int reqWidth, int reqHeight) 
    {

    // First decode with inJustDecodeBounds=true to check dimensions
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeResource(res, resId, options);

    // Calculate inSampleSize
    options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

    // Decode bitmap with inSampleSize set
    options.inJustDecodeBounds = false;
    return BitmapFactory.decodeResource(res, resId, options);
}
public static int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) 
{
    // Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if (height > reqHeight || width > reqWidth) 
    {
        if (width > height) 
        {
            inSampleSize = Math.round((float)height / (float)reqHeight);
        } else {
            inSampleSize = Math.round((float)width / (float)reqWidth);
        }
    }
    return inSampleSize;
}

private Bitmap scaleBitmap(Bitmap bitmap) 
   {

            int iWidth=bitmap.getWidth() ;
            int iHeight=bitmap.getHeight();
            int newWidth=0,newHeight=0;

            float fFactor=(float)iHeight/(float)iWidth; 

            if(iWidth<=iHeight)
            {
                     newWidth = 300;                                    
                     newHeight =(int) (newWidth * fFactor) ;//370;
            }
            else
            {
                    newWidth = 400;                             
                    newHeight =(int) (newWidth * fFactor) ;//370;
            }
               float fScaleWidth = ((float) newWidth) / iWidth;
               float fScaleHeight = ((float) newHeight) / iHeight;

               Matrix matrix = new Matrix();
               // resize the bit map
               matrix.postScale(fScaleWidth, fScaleHeight);

            Bitmap resizedBitmappreview = Bitmap.createBitmap(bitmap, 0, 0,iWidth, iHeight, matrix, true);

            return resizedBitmappreview;
    }
于 2013-03-22T12:32:05.077 回答
0

恐怕这是一个android错误：

https://code.google.com/p/android/issues/detail?id=3072

于 2013-12-18T10:53:15.220 回答