* Not essential at all, some methods are probably to be removed if future * releases. *
* WARNING: most methods for getting/setting values work currently only for
* integer base imageLines
*/
public class ImageLineHelper {
private final static double BIG_VALUE = Double.MAX_VALUE * 0.5;
private final static double BIG_VALUE_NEG = Double.MAX_VALUE * (-0.5);
/**
* Given an indexed line with a palette, unpacks as a RGB array, or RGBA if
* a non nul PngChunkTRNS chunk is passed
*
* @param line
* ImageLine as returned from PngReader
* @param pal
* Palette chunk
* @param buf
* Preallocated array, optional
* @return R G B (A), one sample 0-255 per array element. Ready for
* pngw.writeRowInt()
*/
public static int[] palette2rgb(ImageLine line, final PngChunkPLTE pal, final PngChunkTRNS trns, int[] buf) {
final boolean isalpha = trns != null;
final int channels = isalpha ? 4 : 3;
final int nsamples = line.imgInfo.cols * channels;
if (buf == null || buf.length < nsamples)
buf = new int[nsamples];
if (!line.samplesUnpacked)
line = line.unpackToNewImageLine();
final boolean isbyte = line.sampleType == SampleType.BYTE;
final int nindexesWithAlpha = trns != null ? trns.getPalletteAlpha().length : 0;
for (int c = 0; c < line.imgInfo.cols; c++) {
final int index = isbyte ? (line.scanlineb[c] & 0xFF) : line.scanline[c];
pal.getEntryRgb(index, buf, c * channels);
if (isalpha) {
final int alpha = index < nindexesWithAlpha ? trns.getPalletteAlpha()[index] : 255;
buf[c * channels + 3] = alpha;
}
}
return buf;
}
public static int[] palette2rgb(final ImageLine line, final PngChunkPLTE pal, final int[] buf) {
return palette2rgb(line, pal, null, buf);
}
/**
* what follows is pretty uninteresting/untested/obsolete, subject to change
*/
/**
* Just for basic info or debugging. Shows values for first and last pixel.
* Does not include alpha
*/
public static String infoFirstLastPixels(final ImageLine line) {
return line.imgInfo.channels == 1 ? String.format("first=(%d) last=(%d)", line.scanline[0],
line.scanline[line.scanline.length - 1]) : String.format("first=(%d %d %d) last=(%d %d %d)",
line.scanline[0], line.scanline[1], line.scanline[2], line.scanline[line.scanline.length
- line.imgInfo.channels], line.scanline[line.scanline.length - line.imgInfo.channels + 1],
line.scanline[line.scanline.length - line.imgInfo.channels + 2]);
}
public static String infoFull(final ImageLine line) {
final ImageLineStats stats = new ImageLineStats(line);
return "row=" + line.getRown() + " " + stats.toString() + "\n " + infoFirstLastPixels(line);
}
/**
* Computes some statistics for the line. Not very efficient or elegant,
* mainly for tests. Only for RGB/RGBA Outputs values as doubles (0.0 - 1.0)
*/
static class ImageLineStats {
public double[] prom = { 0.0, 0.0, 0.0, 0.0 }; // channel averages
public double[] maxv = { BIG_VALUE_NEG, BIG_VALUE_NEG, BIG_VALUE_NEG, BIG_VALUE_NEG }; // maximo
public double[] minv = { BIG_VALUE, BIG_VALUE, BIG_VALUE, BIG_VALUE };
public double promlum = 0.0; // maximum global (luminance)
public double maxlum = BIG_VALUE_NEG; // max luminance
public double minlum = BIG_VALUE;
public double[] maxdif = { BIG_VALUE_NEG, BIG_VALUE_NEG, BIG_VALUE_NEG, BIG_VALUE }; // maxima
public final int channels; // diferencia
@Override
public String toString() {
return channels == 3 ? String.format(
"prom=%.1f (%.1f %.1f %.1f) max=%.1f (%.1f %.1f %.1f) min=%.1f (%.1f %.1f %.1f)", promlum, prom[0],
prom[1], prom[2], maxlum, maxv[0], maxv[1], maxv[2], minlum, minv[0], minv[1], minv[2])
+ String.format(" maxdif=(%.1f %.1f %.1f)", maxdif[0], maxdif[1], maxdif[2]) : String.format(
"prom=%.1f (%.1f %.1f %.1f %.1f) max=%.1f (%.1f %.1f %.1f %.1f) min=%.1f (%.1f %.1f %.1f %.1f)",
promlum, prom[0], prom[1], prom[2], prom[3], maxlum, maxv[0], maxv[1], maxv[2], maxv[3], minlum,
minv[0], minv[1], minv[2], minv[3])
+ String.format(" maxdif=(%.1f %.1f %.1f %.1f)", maxdif[0], maxdif[1], maxdif[2], maxdif[3]);
}
public ImageLineStats(final ImageLine line) {
this.channels = line.channels;
if (line.channels < 3)
throw new PngjException("ImageLineStats only works for RGB - RGBA");
int ch = 0;
double lum, x, d;
for (int i = 0; i < line.imgInfo.cols; i++) {
lum = 0;
for (ch = channels - 1; ch >= 0; ch--) {
x = int2double(line, line.scanline[i * channels]);
if (ch < 3)
lum += x;
prom[ch] += x;
if (x > maxv[ch])
maxv[ch] = x;
if (x < minv[ch])
minv[ch] = x;
if (i >= channels) {
d = Math.abs(x - int2double(line, line.scanline[i - channels]));
if (d > maxdif[ch])
maxdif[ch] = d;
}
}
promlum += lum;
if (lum > maxlum)
maxlum = lum;
if (lum < minlum)
minlum = lum;
}
for (ch = 0; ch < channels; ch++) {
prom[ch] /= line.imgInfo.cols;
}
promlum /= (line.imgInfo.cols * 3.0);
maxlum /= 3.0;
minlum /= 3.0;
}
}
/**
* integer packed R G B only for bitdepth=8! (does not check!)
*
**/
public static int getPixelRGB8(final ImageLine line, final int column) {
final int offset = column * line.channels;
return (line.scanline[offset] << 16) + (line.scanline[offset + 1] << 8) + (line.scanline[offset + 2]);
}
public static int getPixelARGB8(final ImageLine line, final int column) {
final int offset = column * line.channels;
return (line.scanline[offset + 3] << 24) + (line.scanline[offset] << 16) + (line.scanline[offset + 1] << 8)
+ (line.scanline[offset + 2]);
}
public static void setPixelsRGB8(final ImageLine line, final int[] rgb) {
for (int i = 0, j = 0; i < line.imgInfo.cols; i++) {
line.scanline[j++] = ((rgb[i] >> 16) & 0xFF);
line.scanline[j++] = ((rgb[i] >> 8) & 0xFF);
line.scanline[j++] = ((rgb[i] & 0xFF));
}
}
public static void setPixelRGB8(final ImageLine line, int col, final int r, final int g, final int b) {
col *= line.channels;
line.scanline[col++] = r;
line.scanline[col++] = g;
line.scanline[col] = b;
}
public static void setPixelRGB8(final ImageLine line, final int col, final int rgb) {
setPixelRGB8(line, col, (rgb >> 16) & 0xFF, (rgb >> 8) & 0xFF, rgb & 0xFF);
}
public static void setPixelsRGBA8(final ImageLine line, final int[] rgb) {
for (int i = 0, j = 0; i < line.imgInfo.cols; i++) {
line.scanline[j++] = ((rgb[i] >> 16) & 0xFF);
line.scanline[j++] = ((rgb[i] >> 8) & 0xFF);
line.scanline[j++] = ((rgb[i] & 0xFF));
line.scanline[j++] = ((rgb[i] >> 24) & 0xFF);
}
}
public static void setPixelRGBA8(final ImageLine line, int col, final int r, final int g, final int b, final int a) {
col *= line.channels;
line.scanline[col++] = r;
line.scanline[col++] = g;
line.scanline[col++] = b;
line.scanline[col] = a;
}
public static void setPixelRGBA8(final ImageLine line, final int col, final int rgb) {
setPixelRGBA8(line, col, (rgb >> 16) & 0xFF, (rgb >> 8) & 0xFF, rgb & 0xFF, (rgb >> 24) & 0xFF);
}
public static void setValD(final ImageLine line, final int i, final double d) {
line.scanline[i] = double2int(line, d);
}
public static int interpol(final int a, final int b, final int c, final int d, final double dx, final double dy) {
// a b -> x (0-1)
// c d
//
final double e = a * (1.0 - dx) + b * dx;
final double f = c * (1.0 - dx) + d * dx;
return (int) (e * (1 - dy) + f * dy + 0.5);
}
public static double int2double(final ImageLine line, final int p) {
return line.bitDepth == 16 ? p / 65535.0 : p / 255.0;
// TODO: replace my multiplication? check for other bitdepths
}
public static double int2doubleClamped(final ImageLine line, final int p) {
// TODO: replace my multiplication?
final double d = line.bitDepth == 16 ? p / 65535.0 : p / 255.0;
return d <= 0.0 ? 0 : (d >= 1.0 ? 1.0 : d);
}
public static int double2int(final ImageLine line, double d) {
d = d <= 0.0 ? 0 : (d >= 1.0 ? 1.0 : d);
return line.bitDepth == 16 ? (int) (d * 65535.0 + 0.5) : (int) (d * 255.0 + 0.5); //
}
public static int double2intClamped(final ImageLine line, double d) {
d = d <= 0.0 ? 0 : (d >= 1.0 ? 1.0 : d);
return line.bitDepth == 16 ? (int) (d * 65535.0 + 0.5) : (int) (d * 255.0 + 0.5); //
}
public static int clampTo_0_255(final int i) {
return i > 255 ? 255 : (i < 0 ? 0 : i);
}
public static int clampTo_0_65535(final int i) {
return i > 65535 ? 65535 : (i < 0 ? 0 : i);
}
public static int clampTo_128_127(final int x) {
return x > 127 ? 127 : (x < -128 ? -128 : x);
}
/**
* Unpacks scanline (for bitdepth 1-2-4) into a array int[]
*
* You can (OPTIONALLY) pass an preallocated array, that will be filled and * returned. If null, it will be allocated *
* If
*
* You probably should use {@link ImageLine#unpackToNewImageLine()}
*
*/
public static int[] unpack(final ImageInfo imgInfo, final int[] src, int[] dst, final boolean scale) {
final int len1 = imgInfo.samplesPerRow;
final int len0 = imgInfo.samplesPerRowPacked;
if (dst == null || dst.length < len1)
dst = new int[len1];
if (imgInfo.packed)
ImageLine.unpackInplaceInt(imgInfo, src, dst, scale);
else
System.arraycopy(src, 0, dst, 0, len0);
return dst;
}
public static byte[] unpack(final ImageInfo imgInfo, final byte[] src, byte[] dst, final boolean scale) {
final int len1 = imgInfo.samplesPerRow;
final int len0 = imgInfo.samplesPerRowPacked;
if (dst == null || dst.length < len1)
dst = new byte[len1];
if (imgInfo.packed)
ImageLine.unpackInplaceByte(imgInfo, src, dst, scale);
else
System.arraycopy(src, 0, dst, 0, len0);
return dst;
}
/**
* Packs scanline (for bitdepth 1-2-4) from array into the scanline
*
* If scale==true, it scales the value (just a bit shift) towards 0-255.
* scale==true, it scales the value (just a bit shift).
*
* You probably should use {@link ImageLine#packToNewImageLine()}
*/
public static int[] pack(final ImageInfo imgInfo, final int[] src, int[] dst, final boolean scale) {
final int len0 = imgInfo.samplesPerRowPacked;
if (dst == null || dst.length < len0)
dst = new int[len0];
if (imgInfo.packed)
ImageLine.packInplaceInt(imgInfo, src, dst, scale);
else
System.arraycopy(src, 0, dst, 0, len0);
return dst;
}
public static byte[] pack(final ImageInfo imgInfo, final byte[] src, byte[] dst, final boolean scale) {
final int len0 = imgInfo.samplesPerRowPacked;
if (dst == null || dst.length < len0)
dst = new byte[len0];
if (imgInfo.packed)
ImageLine.packInplaceByte(imgInfo, src, dst, scale);
else
System.arraycopy(src, 0, dst, 0, len0);
return dst;
}
static int getMaskForPackedFormats(final int bitDepth) { // Utility function for pack/unpack
if (bitDepth == 4)
return 0xf0;
else if (bitDepth == 2)
return 0xc0;
else
return 0x80; // bitDepth == 1
}
static int getMaskForPackedFormatsLs(final int bitDepth) { // Utility function for pack/unpack
if (bitDepth == 4)
return 0x0f;
else if (bitDepth == 2)
return 0x03;
else
return 0x01; // bitDepth == 1
}
}