import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
public static void writeMaskedTwoBitPng(Bitmap blackAndWhiteBitmap, OutputStream stream, boolean transparentBlack)
{
    LightBitmap lightBitmap = new LightBitmap(blackAndWhiteBitmap);
    ImageInfo imageInfo = new ImageInfo(lightBitmap.getWidth(), lightBitmap.getHeight(), 1, false, true, false);
    PngWriter pngWriter = new PngWriter(stream, imageInfo);

    PngChunkTRNS transparencyChunk = pngWriter.getMetadata().createTRNSChunk();
    transparencyChunk.setGray(transparentBlack ? 0 : 1);

    for (int y = 0; y < lightBitmap.getHeight(); y++)
    {
        ImageLineByte imageLine = new ImageLineByte(imageInfo);
        for (int x = 0; x < lightBitmap.getWidth(); x++)
        {
            int pixel = lightBitmap.getPixel(x, y) & 0x00FFFFFF;
            int r = Color.red(pixel);

            imageLine.getScanline()[x] = (byte) (r > 255 / 2 ? 1 : 0);
        }

        pngWriter.writeRow(imageLine, y);
    }

    pngWriter.end();
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
private static int[] palette2rgb(IImageLine line, PngChunkPLTE pal, PngChunkTRNS trns, int[] buf,
                                 boolean alphaForced) {
    boolean isalpha = trns != null;
    int channels = isalpha ? 4 : 3;
    ImageLineInt linei = (ImageLineInt) (line instanceof ImageLineInt ? line : null);
    ImageLineByte lineb = (ImageLineByte) (line instanceof ImageLineByte ? line : null);
    boolean isbyte = lineb != null;
    int cols = linei != null ? linei.imgInfo.cols : lineb.imgInfo.cols;
    int nsamples = cols * channels;
    if (buf == null || buf.length < nsamples)
        buf = new int[nsamples];
    int nindexesWithAlpha = trns != null ? trns.getPalletteAlpha().length : 0;
    for (int c = 0; c < cols; c++) {
        int index = isbyte ? (lineb.scanline[c] & 0xFF) : linei.scanline[c];
        pal.getEntryRgb(index, buf, c * channels);
        if (isalpha) {
            int alpha = index < nindexesWithAlpha ? trns.getPalletteAlpha()[index] : 255;
            buf[c * channels + 3] = alpha;
        }
    }
    return buf;
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
/**
 * Warning: the line should be upscaled, see {@link #scaleUp(IImageLineArray)}
 */
static int[] lineToARGB32(ImageLineByte line, PngChunkPLTE pal, PngChunkTRNS trns, int[] buf) {
    boolean alphachannel = line.imgInfo.alpha;
    int cols = line.getImageInfo().cols;
    if (buf == null || buf.length < cols)
        buf = new int[cols];
    int index, rgb, alpha, ga, g;
    if (line.getImageInfo().indexed) {// palette
        int nindexesWithAlpha = trns != null ? trns.getPalletteAlpha().length : 0;
        for (int c = 0; c < cols; c++) {
            index = line.scanline[c] & 0xFF;
            rgb = pal.getEntry(index);
            alpha = index < nindexesWithAlpha ? trns.getPalletteAlpha()[index] : 255;
            buf[c] = (alpha << 24) | rgb;
        }
    } else if (line.imgInfo.greyscale) { // gray
        ga = trns != null ? trns.getGray() : -1;
        for (int c = 0, c2 = 0; c < cols; c++) {
            g = (line.scanline[c2++] & 0xFF);
            alpha = alphachannel ? line.scanline[c2++] & 0xFF : (g != ga ? 255 : 0);
            buf[c] = (alpha << 24) | g | (g << 8) | (g << 16);
        }
    } else { // true color
        ga = trns != null ? trns.getRGB888() : -1;
        for (int c = 0, c2 = 0; c < cols; c++) {
            rgb =
                    ((line.scanline[c2++] & 0xFF) << 16) | ((line.scanline[c2++] & 0xFF) << 8)
                            | (line.scanline[c2++] & 0xFF);
            alpha = alphachannel ? line.scanline[c2++] & 0xFF : (rgb != ga ? 255 : 0);
            buf[c] = (alpha << 24) | rgb;
        }
    }
    return buf;
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
@Test
public void timePNGJEncode() throws Exception {
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    ColorModel colorModel = image.getColorModel();
    boolean indexed = colorModel instanceof IndexColorModel;
    boolean hasAlpha = colorModel.hasAlpha();
    boolean grayscale = !indexed && colorModel.getNumColorComponents() == 1;
    ImageInfo ii = new ImageInfo(image.getWidth(), image.getHeight(), 8, hasAlpha, grayscale,
            indexed);
    PngWriter pw = new PngWriter(bos, ii);
    pw.setCompLevel(4);
    // pw.setDeflaterStrategy(Deflater.NO_COMPRESSION);
    pw.setFilterType(ar.com.hjg.pngj.FilterType.getByVal(filterType.getType()));

    if (indexed) {
        IndexColorModel icm = (IndexColorModel) colorModel;
        PngChunkPLTE palette = pw.getMetadata().createPLTEChunk();
        int ncolors = icm.getNumComponents();
        palette.setNentries(ncolors);
        for (int i = 0; i < ncolors; i++) {
            palette.setEntry(i, icm.getRed(i), icm.getGreen(i), icm.getBlue(i));
        }
        if (icm.hasAlpha()) {
            PngChunkTRNS transparent = new PngChunkTRNS(ii);
            int[] alpha = new int[ncolors];
            for (int i = 0; i < ncolors; i++) {
                alpha[i] = icm.getAlpha(i);
            }
            transparent.setPalletteAlpha(alpha);
            pw.getChunksList().queue(transparent);

        }
    }

    ScanlineProvider scanlines = ScanlineProviderFactory.getProvider(image);
    for (int row = 0; row < image.getHeight(); row++) {
        pw.writeRow(scanlines);

    }
    pw.end();
    byte[] png = bos.toByteArray();
    collectPng("pngj", png);
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
public void timePNGJEncode(ar.com.hjg.pngj.FilterType filterType, String name) throws Exception {
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    ColorModel colorModel = image.getColorModel();
    boolean indexed = colorModel instanceof IndexColorModel;
    boolean hasAlpha = colorModel.hasAlpha();
    boolean grayscale = !indexed && colorModel.getNumColorComponents() == 1;
    ImageInfo ii = new ImageInfo(image.getWidth(), image.getHeight(), 8, hasAlpha, grayscale,
            indexed);
    PngWriter pw = new PngWriter(bos, ii);
    pw.setCompLevel(compression);
    pw.setFilterType(filterType);

    if (indexed) {
        IndexColorModel icm = (IndexColorModel) colorModel;
        PngChunkPLTE palette = pw.getMetadata().createPLTEChunk();
        int ncolors = icm.getNumComponents();
        palette.setNentries(ncolors);
        for (int i = 0; i < ncolors; i++) {
            palette.setEntry(i, icm.getRed(i), icm.getGreen(i), icm.getBlue(i));
        }
        if (icm.hasAlpha()) {
            PngChunkTRNS transparent = new PngChunkTRNS(ii);
            int[] alpha = new int[ncolors];
            for (int i = 0; i < ncolors; i++) {
                alpha[i] = icm.getAlpha(i);
            }
            transparent.setPalletteAlpha(alpha);
            pw.getChunksList().queue(transparent);

        }
    }

    ScanlineProvider scanlines = ScanlineProviderFactory.getProvider(image);
    for (int row = 0; row < image.getHeight(); row++) {
        pw.writeRow(scanlines);
    }
    pw.end();
    byte[] png = bos.toByteArray();
    collectPng(name, png);
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
public byte [] encodeIndexedPNG (int [] pixels, int width, int height, boolean color, int bits) {
    ByteArrayOutputStream bos = new ByteArrayOutputStream();

    int [] palette = getPalette();

    boolean alpha = Color.alpha(palette[0]) == 0;
    boolean grayscale = !color;
    //Log.d(TAG, "encodeIndexedPNG: color = "+color +", alpha ="+alpha+", grayscale = "+grayscale);

    //ImageInfo imageInfo = new ImageInfo(width, height, bits, alpha, grayscale, color);
    ImageInfo imageInfo = new ImageInfo(width, height, bits, false, grayscale, color);
    PngWriter writer = new PngWriter(bos, imageInfo);
    writer.getPixelsWriter().setDeflaterCompLevel(9);

    if (color) {
        PngChunkPLTE paletteChunk = writer.getMetadata().createPLTEChunk();
        paletteChunk.setNentries(palette.length);

        for (int i = 0; i < palette.length; i++) {
            int c = palette[i];
            paletteChunk.setEntry(i, Color.red(c), Color.green(c), Color.blue(c));
        }
    }

    if (alpha) {
        PngChunkTRNS trnsChunk = writer.getMetadata().createTRNSChunk();
        if (color) {
            trnsChunk.setIndexEntryAsTransparent(0);
        } else {
            trnsChunk.setGray(1);
        }
    }
    else {
        quantize(pixels, imageInfo.cols);
    }
    ImageLineInt line = new ImageLineInt(imageInfo);
    for (int y = 0; y < imageInfo.rows; y++) {
        int [] lineData = line.getScanline();
        for (int x = 0; x < imageInfo.cols; x++) {
            int pixel = pixels[y * imageInfo.cols + x];
            //lineData[x] = getNearestColorIndex(pixel) ^ (x % 2) ^ (y % 2);
            lineData[x] = getNearestColorIndex(pixel);
        }
        writer.writeRow(line);
    }

    writer.end();
    return bos.toByteArray();
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
public byte [] encodeIndexedPNG (int [] pixels, int width, int height, boolean color, int bits) {
    ByteArrayOutputStream bos = new ByteArrayOutputStream();

    int [] palette = getPalette();

    boolean alpha = Color.alpha(palette[0]) == 0;
    boolean grayscale = !color;
    //Log.d(TAG, "encodeIndexedPNG: color = "+color +", alpha ="+alpha+", grayscale = "+grayscale);

    //ImageInfo imageInfo = new ImageInfo(width, height, bits, alpha, grayscale, color);
    ImageInfo imageInfo = new ImageInfo(width, height, bits, false, grayscale, color);
    PngWriter writer = new PngWriter(bos, imageInfo);
    writer.getPixelsWriter().setDeflaterCompLevel(9);

    if (color) {
        PngChunkPLTE paletteChunk = writer.getMetadata().createPLTEChunk();
        paletteChunk.setNentries(palette.length);

        for (int i = 0; i < palette.length; i++) {
            int c = palette[i];
            paletteChunk.setEntry(i, Color.red(c), Color.green(c), Color.blue(c));
        }
    }

    if (alpha) {
        PngChunkTRNS trnsChunk = writer.getMetadata().createTRNSChunk();
        if (color) {
            trnsChunk.setIndexEntryAsTransparent(0);
        } else {
            trnsChunk.setGray(1);
        }
    }
    else {
        quantize(pixels, imageInfo.cols);
    }
    ImageLineInt line = new ImageLineInt(imageInfo);
    for (int y = 0; y < imageInfo.rows; y++) {
        int [] lineData = line.getScanline();
        for (int x = 0; x < imageInfo.cols; x++) {
            int pixel = pixels[y * imageInfo.cols + x];

            lineData[x] = getNearestColorIndex(pixel);
        }
        writer.writeRow(line);
    }

    writer.end();
    return bos.toByteArray();
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
/**
 * Warning: the line should be upscaled, see {@link #scaleUp(IImageLineArray)}
 */
static byte[] lineToRGBA8888(ImageLineByte line, PngChunkPLTE pal, PngChunkTRNS trns, byte[] buf) {
    boolean alphachannel = line.imgInfo.alpha;
    int cols = line.imgInfo.cols;
    int bytes = cols * 4;
    if (buf == null || buf.length < bytes)
        buf = new byte[bytes];
    int index, rgb, ga;
    byte val;
    if (line.imgInfo.indexed) {// palette
        int nindexesWithAlpha = trns != null ? trns.getPalletteAlpha().length : 0;
        for (int c = 0, b = 0; c < cols; c++) {
            index = line.scanline[c] & 0xFF;
            rgb = pal.getEntry(index);
            buf[b++] = (byte) ((rgb >> 16) & 0xFF);
            buf[b++] = (byte) ((rgb >> 8) & 0xFF);
            buf[b++] = (byte) (rgb & 0xFF);
            buf[b++] = (byte) (index < nindexesWithAlpha ? trns.getPalletteAlpha()[index] : 255);
        }
    } else if (line.imgInfo.greyscale) { //
        ga = trns != null ? trns.getGray() : -1;
        for (int c = 0, b = 0; b < bytes; ) {
            val = line.scanline[c++];
            buf[b++] = val;
            buf[b++] = val;
            buf[b++] = val;
            buf[b++] =
                    alphachannel ? line.scanline[c++] : ((int) (val & 0xFF) == ga) ? (byte) 0 : (byte) 255;
        }
    } else { // true color
        if (alphachannel) // same format!
            System.arraycopy(line.scanline, 0, buf, 0, bytes);
        else {
            for (int c = 0, b = 0; b < bytes; ) {
                buf[b++] = line.scanline[c++];
                buf[b++] = line.scanline[c++];
                buf[b++] = line.scanline[c++];
                buf[b++] = (byte) (255); // tentative (probable)
                if (trns != null && buf[b - 3] == (byte) trns.getRGB()[0]
                        && buf[b - 2] == (byte) trns.getRGB()[1] && buf[b - 1] == (byte) trns.getRGB()[2]) // not
                    // very
                    // efficient,
                    // but
                    // not
                    // frecuent
                    buf[b - 1] = 0;
            }
        }
    }
    return buf;
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
/**
 * this is not very efficient, only for tests and troubleshooting
 */
public static int[] convert2rgba(IImageLineArray line, PngChunkPLTE pal, PngChunkTRNS trns,
                                 int[] buf) {
    ImageInfo imi = line.getImageInfo();
    int nsamples = imi.cols * 4;
    if (buf == null || buf.length < nsamples)
        buf = new int[nsamples];
    int maxval = imi.bitDepth == 16 ? (1 << 16) - 1 : 255;
    Arrays.fill(buf, maxval);

    if (imi.indexed) {
        int tlen = trns != null ? trns.getPalletteAlpha().length : 0;
        for (int s = 0; s < imi.cols; s++) {
            int index = line.getElem(s);
            pal.getEntryRgb(index, buf, s * 4);
            if (index < tlen) {
                buf[s * 4 + 3] = trns.getPalletteAlpha()[index];
            }
        }
    } else if (imi.greyscale) {
        int[] unpack = null;
        if (imi.bitDepth < 8)
            unpack = ImageLineHelper.DEPTH_UNPACK[imi.bitDepth];
        for (int s = 0, i = 0, p = 0; p < imi.cols; p++) {
            buf[s++] = unpack != null ? unpack[line.getElem(i++)] : line.getElem(i++);
            buf[s] = buf[s - 1];
            s++;
            buf[s] = buf[s - 1];
            s++;
            if (imi.channels == 2)
                buf[s++] = unpack != null ? unpack[line.getElem(i++)] : line.getElem(i++);
            else
                buf[s++] = maxval;
        }
    } else {
        for (int s = 0, i = 0, p = 0; p < imi.cols; p++) {
            buf[s++] = line.getElem(i++);
            buf[s++] = line.getElem(i++);
            buf[s++] = line.getElem(i++);
            buf[s++] = imi.alpha ? line.getElem(i++) : maxval;
        }
    }
    return buf;
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
private void roundTripPNGJ(BufferedImage original, RenderedImage source) throws IOException {
    ColorModel colorModel = source.getColorModel();
    boolean indexed = colorModel instanceof IndexColorModel;
    boolean hasAlpha = colorModel.hasAlpha();
    ScanlineProvider scanlines = ScanlineProviderFactory.getProvider(source);
    int numColorComponents = colorModel.getNumColorComponents();
    boolean grayscale = !indexed && numColorComponents < 3;
    byte bitDepth = scanlines.getBitDepth();
    ImageInfo ii = new ImageInfo(source.getWidth(), source.getHeight(), bitDepth, hasAlpha, grayscale,
            indexed);
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    PngWriter pw = new PngWriter(bos, ii);
    pw.setCompLevel(4);
    pw.setFilterType(ar.com.hjg.pngj.FilterType.FILTER_NONE);

    if (indexed) {
        IndexColorModel icm = (IndexColorModel) colorModel;
        PngChunkPLTE palette = pw.getMetadata().createPLTEChunk();
        int ncolors = icm.getMapSize();
        palette.setNentries(ncolors);
        for (int i = 0; i < ncolors; i++) {
            final int red = icm.getRed(i);
            final int green = icm.getGreen(i);
            final int blue = icm.getBlue(i);
            palette.setEntry(i, red, green, blue);
        }
        if (icm.hasAlpha()) {
            PngChunkTRNS transparent = new PngChunkTRNS(ii);
            int[] alpha = new int[ncolors];
            for (int i = 0; i < ncolors; i++) {
                final int a = icm.getAlpha(i);
                alpha[i] = a;
            }
            transparent.setPalletteAlpha(alpha);
            pw.getChunksList().queue(transparent);

        }
    }

    for (int row = 0; row < source.getHeight(); row++) {
        pw.writeRow(scanlines);
    }
    pw.end();

    byte[] bytes = bos.toByteArray();
    writeToFile(new File("./target/roundTripNone", sourceFile.getName()), bytes);

    ByteArrayInputStream bis = new ByteArrayInputStream(bytes);
    BufferedImage image = ImageIO.read(bis);

    assertEquals(original.getWidth(), image.getWidth());
    assertEquals(original.getHeight(), image.getHeight());
    // we cannot match in output the image types generated by the CLIB reader, they are not
    // really matching the PNG data model
    if(!clibAvailable) {
        assertEquals(original.getSampleModel(), image.getSampleModel());
        assertEquals(original.getColorModel(), image.getColorModel());
    }

    for (int x = 0; x < original.getWidth(); x++) {
        for (int y = 0; y < original.getHeight(); y++) {
            int rgbOriginal = original.getRGB(x, y);
            int rgbActual = image.getRGB(x, y);
            assertEquals("Comparison failed at " + x + "," + y, rgbOriginal, rgbActual);
        }
    }
}
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
@Test
    public void timePNGJEncode() throws Exception {
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        ColorModel colorModel = image.getColorModel();
        boolean indexed = colorModel instanceof IndexColorModel;
        boolean hasAlpha = colorModel.hasAlpha();
        boolean grayscale = !indexed && colorModel.getNumColorComponents() == 1;
        ImageInfo ii = new ImageInfo(image.getWidth(), image.getHeight(), 8, hasAlpha, grayscale,
                indexed);
        PngWriter pw = new PngWriter(bos, ii);
        pw.setCompLevel(compression);
//       pw.setDeflaterStrategy(Deflater.NO_COMPRESSION);
        pw.setFilterType(filterType);

        if (indexed) {
            IndexColorModel icm = (IndexColorModel) colorModel;
            PngChunkPLTE palette = pw.getMetadata().createPLTEChunk();
            int ncolors = icm.getNumComponents();
            palette.setNentries(ncolors);
            for (int i = 0; i < ncolors; i++) {
                palette.setEntry(i, icm.getRed(i), icm.getGreen(i), icm.getBlue(i));
            }
            if (icm.hasAlpha()) {
                PngChunkTRNS transparent = new PngChunkTRNS(ii);
                int[] alpha = new int[ncolors];
                for (int i = 0; i < ncolors; i++) {
                    alpha[i] = icm.getAlpha(i);
                }
                transparent.setPalletteAlpha(alpha);
                pw.getChunksList().queue(transparent);

            }
        }

        ScanlineProvider scanlines = ScanlineProviderFactory.getProvider(image);
        for (int row = 0; row < image.getHeight(); row++) {
            pw.writeRow(scanlines);

        }
        pw.end();
        byte[] png = bos.toByteArray();
        collectPng("pngj", png);
    }
 

import ar.com.hjg.pngj.chunks.PngChunkTRNS; //导入依赖的package包/类
/**
 * Same as palette2rgbx , but returns rgba always, even if trns is null
 *
 * @param line ImageLine as returned from PngReader
 * @param pal  Palette chunk
 * @param trns Transparency chunk, can be null (absent)
 * @param buf  Preallocated array, optional
 * @return R G B (A), one sample 0-255 per array element. Ready for pngw.writeRowInt()
 */
public static int[] palette2rgba(ImageLineInt line, PngChunkPLTE pal, PngChunkTRNS trns, int[] buf) {
    return palette2rgb(line, pal, trns, buf, true);
}