Recreate Image from DCT coefficients
Does anyone know how to recreate the image from its dct coefficients (dctData)?
rgbImage = JAI.create("fileload", filename);
rgbWidth = rgbImage.getWidth();
rgbHeight = rgbImage.getHeight();
//dct
ParameterBlock pbDCT = (new ParameterBlock()).addSource(rgbImage);
PlanarImage dct;
dct = JAI.create("dct", pbDCT,null);
double[] dctData = dct.getData().getPixels(0, 0, rgbWidth, rgbHeight, (double[])null);
# 1
I found out that i can recreate the image from its pixels by using this
[CODE]MemoryImageSource imSource = new MemoryImageSource(rgbWidth, rgbHeight, dctData, 0, rgbWidth);[/CODE]
However i get the following error
The method createImage(MemoryImageSource) is undefined for the type ImageProcessingJAIDCT
I have changed dctData to int[] and imported everything from http://www.cs.cmu.edu/~illah/HOWTO/javaimage.txt
# 2
I also tried the following codes but the image i gain is just grayscale spots..
DataBuffer buffer = new DataBufferInt(dctData, dctData.length);
int[] bitMasks = {0xff0000, 0xff00, 0xff, 0xff000000}; //r, g, b, a
SampleModel sm = new SinglePixelPackedSampleModel(DataBuffer.TYPE_INT, rgbWidth, rgbHeight, bitMasks);
WritableRaster raster = Raster.createWritableRaster(sm, buffer, null);
ColorModel cm = ColorModel.getRGBdefault();
BufferedImage bi = new BufferedImage(cm, raster, false, null);
//idct
ParameterBlock pbIDCT = (new ParameterBlock()).addSource(bi);
PlanarImage idct = JAI.create("idct", pbIDCT, null);
and
BufferedImage outImage = new BufferedImage(rgbWidth, rgbHeight, BufferedImage.TYPE_BYTE_GRAY );
outImage.setRGB(0, 0, rgbWidth, rgbHeight, dctData, 0, rgbWidth);
ParameterBlock pbIDCT = (new ParameterBlock()).addSource(outImage);
PlanarImage idct = JAI.create("idct", pbIDCT, null);
