JAI - Creating High Quality thumbnails

Question

I am using JAI to take in large images and proportionally resize it to around ~300 x 220 image.
Using the "scale" returns horrible quality
ParameterBlock pb2 = new ParameterBlock();
pb2.addSource( src );
pb2.add( scale );
pb2.add( scale );
pb2.add( 0.0f );
pb2.add( 0.0f );
JAI.create( "scale", pb2, null );Using "subsampleaverage" is much better, but still returns worse quality than the original.
ParameterBlock pb2 = new ParameterBlock();
pb2.addSource( src ); // The source image
pb2.add( ( double ) scale ); // The xScale
pb2.add( ( double ) scale ); // The yScale
pb2.add( new InterpolationBicubic2(8) ); // The interpolation...I Tried all Interpolation Types already
JAI.create( "subsampleaverage", pb2, null );I want an exact quality copy of the original. Is there a way to do this in JAI?

Answer 1

I mean in photoshop it saves much clearer (higher
quality image) than through JAI. I know in Photoshop
you can choose clarity on a scale from 1 to 12 when
saving image files for the web. The only thing I see
in JAI is interpolation which provides 3 or 4 choices.Ah, you mean the JPEG codec quality level. JAI's JPEGTileCodecDescriptor has a quality resource:
"A factor that relates to the desired tradeoff between image quality and the image data compression ratio. The range of this parameter is from 0.0 to 1.0. A setting of 1.0 produces the highest quality image at a lower compression rate. A setting of 0.0 produces the highest compression ratio, with a sacrifice to image quality. The default value is 0.75."