componentcolormodel.java

JAVA基本类源代码,大家可以学习学习!

                lowVal = getNormalizedComponents(spixel, null, 0);
                for (int i = 0; i < numColorComponents; i++) {
                    spixel[i] = 32767;
                }
                highVal = getNormalizedComponents(spixel, null, 0);
            }
            break;
        default:
            lowVal = highVal = null;  // to keep the compiler from complaining
            break;
        }
        nonStdScale = false;
        for (int i = 0; i < numColorComponents; i++) {
            if ((lowVal[i] != 0.0f) || (highVal[i] != 1.0f)) {
                nonStdScale = true;
                break;
            }
        }
        if (nonStdScale) {
            noUnnorm = true;
            is_sRGB_stdScale = false;
            is_LinearRGB_stdScale = false;
            is_LinearGray_stdScale = false;
            is_ICCGray_stdScale = false;
            compOffset = new float[numColorComponents];
            compScale = new float[numColorComponents];
            for (int i = 0; i < numColorComponents; i++) {
                compOffset[i] = lowVal[i];
                compScale[i] = 1.0f / (highVal[i] - lowVal[i]);
            }
        }
    }

    private int getRGBComponent(int pixel, int idx) {
        if (numComponents > 1) {
            throw new
                IllegalArgumentException("More than one component per pixel");
        }
        if (signed) {
            throw new
                IllegalArgumentException("Component value is signed");
        }
        if (needScaleInit) {
            initScale();
        }
        // Since there is only 1 component, there is no alpha

        // Normalize the pixel in order to convert it
        Object opixel = null;
        switch (transferType) {
        case DataBuffer.TYPE_BYTE:
            {
                byte[] bpixel = { (byte) pixel };
                opixel = bpixel;
            }
            break;
        case DataBuffer.TYPE_USHORT:
            {
                short[] spixel = { (short) pixel };
                opixel = spixel;
            }
            break;
        case DataBuffer.TYPE_INT:
            {
                int[] ipixel = { pixel };
                opixel = ipixel;
            }
            break;
        }
        float[] norm = getNormalizedComponents(opixel, null, 0);
        float[] rgb = colorSpace.toRGB(norm);

        return (int) (rgb[idx] * 255.0f + 0.5f);
    }

    /**
     * Returns the red color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB ColorSpace, sRGB.  A color conversion
     * is done if necessary.  The pixel value is specified as an int.
     * The returned value will be a non pre-multiplied value. 
     * If the alpha is premultiplied, this method divides
     * it out before returning the value (if the alpha value is 0,
     * the red value will be 0).
     *
     * @param pixel The pixel from which you want to get the red color component.
     *
     * @return The red color component for the specified pixel, as an int.
     *
     * @throws IllegalArgumentException If there is more than
     * one component in this <CODE>ColorModel</CODE>. 
     * @throws IllegalArgumentException If the component value for this
     * <CODE>ColorModel</CODE> is signed
     */
    public int getRed(int pixel) {
        return getRGBComponent(pixel, 0);
    }

    /**
     * Returns the green color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB ColorSpace, sRGB.  A color conversion
     * is done if necessary.  The pixel value is specified as an int.
     * The returned value will be a non
     * pre-multiplied value. If the alpha is premultiplied, this method
     * divides it out before returning the value (if the alpha value is 0,
     * the green value will be 0).
     *
     * @param pixel The pixel from which you want to get the green color component.
     *
     * @return The green color component for the specified pixel, as an int.
     *
     * @throws IllegalArgumentException If there is more than
     * one component in this <CODE>ColorModel</CODE>. 
     * @throws IllegalArgumentException If the component value for this
     * <CODE>ColorModel</CODE> is signed
     */
    public int getGreen(int pixel) {
        return getRGBComponent(pixel, 1);
    }

    /**
     * Returns the blue color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB ColorSpace, sRGB.  A color conversion
     * is done if necessary.  The pixel value is specified as an int.
     * The returned value will be a non
     * pre-multiplied value. If the alpha is premultiplied, this method
     * divides it out before returning the value (if the alpha value is 0,
     * the blue value will be 0).
     *
     * @param pixel The pixel from which you want to get the blue color component.
     *
     * @return The blue color component for the specified pixel, as an int.
     *
     * @throws IllegalArgumentException If there is more than
     * one component in this <CODE>ColorModel</CODE>. 
     * @throws IllegalArgumentException If the component value for this
     * <CODE>ColorModel</CODE> is signed
     */
    public int getBlue(int pixel) {
        return getRGBComponent(pixel, 2);
    }

    /**
     * Returns the alpha component for the specified pixel, scaled
     * from 0 to 255.   The pixel value is specified as an int.
     *
     * @param pixel The pixel from which you want to get the alpha component.
     *
     * @return The alpha component for the specified pixel, as an int.
     *
     * @throws IllegalArgumentException If there is more than
     * one component in this <CODE>ColorModel</CODE>. 
     * @throws IllegalArgumentException If the component value for this
     * <CODE>ColorModel</CODE> is signed
     */
    public int getAlpha(int pixel) {
        if (supportsAlpha == false) {
            return 255;
        }
        if (numComponents > 1) {
            throw new
                IllegalArgumentException("More than one component per pixel");
        }
        if (signed) {
            throw new
                IllegalArgumentException("Component value is signed");
        }

        return (int) ((((float) pixel) / ((1<<nBits[0])-1)) * 255.0f + 0.5f);
    }

    /**
     * Returns the color/alpha components of the pixel in the default
     * RGB color model format.  A color conversion is done if necessary.
     * The returned value will be in a non pre-multiplied format. If
     * the alpha is premultiplied, this method divides it out of the
     * color components (if the alpha value is 0, the color values will be 0).
     *
     * @param pixel The pixel from which you want to get the color/alpha components.
     *
     * @return The color/alpha components for the specified pixel, as an int.
     *
     * @throws IllegalArgumentException If there is more than
     * one component in this <CODE>ColorModel</CODE>. 
     * @throws IllegalArgumentException If the component value for this
     * <CODE>ColorModel</CODE> is signed
     */
    public int getRGB(int pixel) {
        if (numComponents > 1) {
            throw new
                IllegalArgumentException("More than one component per pixel");
        }
        if (signed) {
            throw new
                IllegalArgumentException("Component value is signed");
        }

	return (getAlpha(pixel) << 24)
	    | (getRed(pixel) << 16)
	    | (getGreen(pixel) << 8)
	    | (getBlue(pixel) << 0);
    }

    private int extractComponent(Object inData, int idx, int precision) {
        // Extract component idx from inData.  The precision argument
        // should be either 8 or 16.  If it's 8, this method will return
        // an 8-bit value.  If it's 16, this method will return a 16-bit
        // value for transferTypes other than TYPE_BYTE.  For TYPE_BYTE,
        // an 8-bit value will be returned.

        // This method maps the input value corresponding to a
        // normalized ColorSpace component value of 0.0 to 0, and the
        // input value corresponding to a normalized ColorSpace
        // component value of 1.0 to 2^n - 1 (where n is 8 or 16), so
        // it is appropriate only for ColorSpaces with min/max component
        // values of 0.0/1.0.  This will be true for sRGB, the built-in
        // Linear RGB and Linear Gray spaces, and any other ICC grayscale
        // spaces for which we have precomputed LUTs.

        boolean needAlpha = (supportsAlpha && isAlphaPremultiplied);
        int alp = 0;
        int comp;

        switch (transferType) {
            // Note: we do no clamping of the pixel data here - we
            // assume that the data is scaled properly
            case DataBuffer.TYPE_SHORT: {
                short sdata[] = (short[]) inData;
                float scalefactor = (float) ((1 << precision) - 1);
                if (needAlpha) {
                    short s = sdata[numColorComponents];
                    if (s != (short) 0) {
                        return (int) ((((float) sdata[idx]) /
                                       ((float) s)) * scalefactor + 0.5f);
                    } else {
                        return 0;
                    }
                } else {
                    return (int) ((sdata[idx] / 32767.0f) * scalefactor + 0.5f);
                }
            }
            case DataBuffer.TYPE_FLOAT: {
                float fdata[] = (float[]) inData;
                float scalefactor = (float) ((1 << precision) - 1);
                if (needAlpha) {
                    float f = fdata[numColorComponents];
                    if (f != 0.0f) {
                        return (int) (((fdata[idx] / f) * scalefactor) + 0.5f);
                    } else {
                        return 0;
                    }
                } else {
                    return (int) (fdata[idx] * scalefactor + 0.5f);
                }
            }
            case DataBuffer.TYPE_DOUBLE: {
                double ddata[] = (double[]) inData;
                double scalefactor = (double) ((1 << precision) - 1);
                if (needAlpha) {
                    double d = ddata[numColorComponents];
                    if (d != 0.0) {
                        return (int) (((ddata[idx] / d) * scalefactor) + 0.5);
                    } else {
                        return 0;
                    }
                } else {
                    return (int) (ddata[idx] * scalefactor + 0.5);
                }
            }
            case DataBuffer.TYPE_BYTE:
               byte bdata[] = (byte[])inData;
               comp = bdata[idx] & 0xff;
               precision = 8;
               if (needAlpha) {
                   alp = bdata[numColorComponents] & 0xff;
               }
            break;
            case DataBuffer.TYPE_USHORT:
               short usdata[] = (short[])inData;
               comp = usdata[idx]&0xffff;