Resizing JPG using Graphics2D

[Terence Thant Zin Oo]

Hi

I have the following code to resize the images.

BufferedImage img; // the image to resize
int type = img.getType();
BufferedImage newImg = new BufferedImage(newWidth, newHeight, type);  
Graphics2D g = newImg.createGraphics();  
g.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);  
g.drawImage(img, 0, 0, newWidth, newHeight, 0, 0, img.getWidth(), img.getHeight(), null);  
g.dispose(); 

I tried to resize these 2 photos -

pic1.jpg: JFIF standard 1.02, 4200x2800, 1.5 MB
pic2.jpg: EXIF standard, 2500x1900, 1.8 MB



It took a few seconds (3, 4 sec) to resize pic2.jpg but took more than one minute to resize pic1.jpg.

Is there any way to improve the performance the above code snippet?

Which attribute decide the performance of image resizing?
Is is the size of the image? or the resolution? or the encoding? or any other criteria?


Your advice would be really appreciated because I don't have much experience in image processing.


Thanks and regards
Terence

[Mikko Kohtamäki]

try googling AffineTransformOp

[Campbell Ritchie]

To expand about AffineTransforms: you can scale, translate, rotate or shear your Graphics object. Either use the AffineTransform class or those methods in the Graphics2Dclass.

Beware: because of the imprecision of floating-point arithmetic it is difficult to undo a transform (shear is the worst offender), so you are probably better off using a copy Graphics object from the create method of the graphics classes.