Java create BufferedImage with float precision

问题

I created a map editor in Java. The problem is, I have steps for every byte value, so the map isn't smooth. Is it possible to change the BufferedImage raster data to float data and draw in float precision on it?

回答1:

To answer your question, yes, you can create a BufferedImage with float precision. It is however a little unclear if this will help you solve your problem.

In any case, here's working example code for creating a BufferedImage with float precision:

public class FloatImage {
    public static void main(String[] args) {
        // Define dimensions and layout of the image
        int w = 300;
        int h = 200;
        int bands = 4; // 4 bands for ARGB, 3 for RGB etc
        int[] bandOffsets = {0, 1, 2, 3}; // length == bands, 0 == R, 1 == G, 2 == B and 3 == A

        // Create a TYPE_FLOAT sample model (specifying how the pixels are stored)
        SampleModel sampleModel = new PixelInterleavedSampleModel(DataBuffer.TYPE_FLOAT, w, h, bands, w  * bands, bandOffsets);
        // ...and data buffer (where the pixels are stored)
        DataBuffer buffer = new DataBufferFloat(w * h * bands);

        // Wrap it in a writable raster
        WritableRaster raster = Raster.createWritableRaster(sampleModel, buffer, null);

        // Create a color model compatible with this sample model/raster (TYPE_FLOAT)
        // Note that the number of bands must equal the number of color components in the 
        // color space (3 for RGB) + 1 extra band if the color model contains alpha 
        ColorSpace colorSpace = ColorSpace.getInstance(ColorSpace.CS_sRGB);
        ColorModel colorModel = new ComponentColorModel(colorSpace, true, false, Transparency.TRANSLUCENT, DataBuffer.TYPE_FLOAT);

        // And finally create an image with this raster
        BufferedImage image = new BufferedImage(colorModel, raster, colorModel.isAlphaPremultiplied(), null);

        System.out.println("image = " + image);
    }
}

For map elevation data, using a single band (bands = 1; bandOffsets = {0};) and a grayscale color space (ColorSpace.CS_GRAY) and no transparency may make more sense.

来源：https://stackoverflow.com/questions/26766751/java-create-bufferedimage-with-float-precision