Example usage for javax.imageio ImageReadParam getSourceBands

Introduction

In this page you can find the example usage for javax.imageio ImageReadParam getSourceBands.

Prototype

public int[] getSourceBands() 

Source Link

Document

Returns the set of source bands to be used.

Usage

From source file:nitf.imageio.NITFReader.java

@Override
public Raster readRaster(int imageIndex, ImageReadParam param) throws IOException {
    checkIndex(imageIndex);/*from w ww  .  j ava  2  s.  c  om*/

    Rectangle sourceRegion = new Rectangle();
    Rectangle destRegion = new Rectangle();
    computeRegions(param, getWidth(imageIndex), getHeight(imageIndex), null, sourceRegion, destRegion);

    // Set everything to default values
    int sourceXSubsampling = param != null ? param.getSourceXSubsampling() : 1;
    int sourceYSubsampling = param != null ? param.getSourceYSubsampling() : 1;
    Point destinationOffset = param != null ? param.getDestinationOffset() : new Point(0, 0);

    ImageSubheader subheader;
    try {
        subheader = record.getImages()[imageIndex].getSubheader();
    } catch (NITFException e) {
        throw new IOException(ExceptionUtils.getStackTrace(e));
    }
    String irep = subheader.getImageRepresentation().getStringData().trim();
    String pvType = subheader.getPixelValueType().getStringData().trim();
    int nbpp = subheader.getNumBitsPerPixel().getIntData();
    int bandCount = subheader.getBandCount();

    // make the band offsets array, for the output
    int[] bandOffsets = null;
    int[] sourceBands = param != null ? param.getSourceBands() : null;
    if (param != null && param.getDestinationBands() != null)
        bandOffsets = param.getDestinationBands();
    else if (param != null && sourceBands != null) {
        bandOffsets = new int[sourceBands.length];
        for (int i = 0; i < bandOffsets.length; i++)
            bandOffsets[i] = sourceBands[i];
    } else {
        // Setup band offsets -- TODO should we really read ALL bands by
        // default?
        bandOffsets = new int[bandCount];
        for (int i = 0; i < bandOffsets.length; i++)
            bandOffsets[i] = i;
    }

    int nBytes = ((nbpp - 1) / 8) + 1;

    int bufType = -1;

    // byte
    if (nBytes == 1) {
        bufType = DataBuffer.TYPE_BYTE;
    }
    // short
    else if (nBytes == 2) {
        bufType = DataBuffer.TYPE_USHORT;
    }
    // float
    else if (nBytes == 4 && pvType.equals("R")) {
        bufType = DataBuffer.TYPE_FLOAT;
    }
    // double
    else if (nBytes == 8 && pvType.equals("R")) {
        bufType = DataBuffer.TYPE_DOUBLE;
    } else {
        throw new NotImplementedException("not yet implemented");
    }

    WritableRaster ras = ImageIOUtils.makeGenericPixelInterleavedWritableRaster(destRegion.width,
            destRegion.height, bandOffsets.length, bufType);
    checkReadParamBandSettings(param, bandCount, ras.getSampleModel().getNumBands());
    readRaster(imageIndex, sourceRegion, destRegion, sourceXSubsampling, sourceYSubsampling, bandOffsets,
            nBytes, destinationOffset, ras);
    return ras;
}

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From source file:nitf.imageio.NITFReader.java

@Override
public BufferedImage read(int imageIndex, ImageReadParam param) throws IOException {
    readHeader();//from  w  w w . jav a  2  s .co  m
    Raster raster = readRaster(imageIndex, param);

    // get the requested number of destination bands (or 0 for all)
    int numDestBands = param != null ? (param.getDestinationBands() != null ? param.getDestinationBands().length
            : param.getSourceBands() != null ? param.getSourceBands().length : 0) : 0;

    // try to find a good match for the specifier
    ImageTypeSpecifier imageType = null, firstType = null;
    Iterator<ImageTypeSpecifier> imageTypes = getImageTypes(imageIndex);
    while (imageTypes.hasNext() && imageType == null) {
        ImageTypeSpecifier currentImageType = imageTypes.next();
        if (firstType == null)
            firstType = currentImageType;

        if (currentImageType.getNumBands() == numDestBands)
            imageType = currentImageType;
    }

    if (imageType == null) {
        if (firstType == null)
            throw new IOException("Unable to determine the ImageTypeSpecifier");
        else
            imageType = firstType;
    }

    try {
        ImageSubheader subheader = record.getImages()[imageIndex].getSubheader();
        String pvType = subheader.getPixelValueType().getStringData().trim();
        int nbpp = subheader.getNumBitsPerPixel().getIntData();
        int nBytes = ((nbpp - 1) / 8) + 1;

        if (nBytes == 1 || nBytes == 2 || (nBytes == 4 && pvType.equals("R"))
                || (nBytes == 8 && pvType.equals("R"))) {
            return ImageIOUtils.rasterToBufferedImage(raster, imageType);
        }
    } catch (NITFException e) {
        throw new IOException(ExceptionUtils.getStackTrace(e));
    }
    throw new NotImplementedException("Image pixel type or bits per pixel not yet supported");
}

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