org.jpedal.parser.image.downsample.OneBitDownSampler Maven / Gradle / Ivy
/*
* ===========================================
* Java Pdf Extraction Decoding Access Library
* ===========================================
*
* Project Info: http://www.idrsolutions.com
* Help section for developers at http://www.idrsolutions.com/support/
*
* (C) Copyright 1997-2017 IDRsolutions and Contributors.
*
* This file is part of JPedal/JPDF2HTML5
*
@LICENSE@
*
* ---------------
* OneBitDownSampler.java
* ---------------
*/
package org.jpedal.parser.image.downsample;
import org.jpedal.color.ColorSpaces;
import org.jpedal.color.DeviceRGBColorSpace;
import org.jpedal.color.GenericColorSpace;
import org.jpedal.images.SamplingFactory;
import org.jpedal.parser.image.PdfImageTypes;
import org.jpedal.parser.image.data.ImageData;
/**
* @author markee
*/
class OneBitDownSampler {
public static GenericColorSpace downSample(final int sampling, final ImageData imageData, GenericColorSpace decodeColorData) {
final byte[] data = imageData.getObjectData();
final int[] flag = {1, 2, 4, 8, 16, 32, 64, 128};
/* if(sampling>2){
System.out.println("downSample ="+sampling);
int newW=imageData.getWidth()>>1;
int newH=imageData.getHeight()>>1;
final int origLineLength= (imageData.getWidth()+7)>>3;
final int newLineLength= (newW+7)>>3;
int size=(newLineLength*newH);
byte[] newData=new byte[size];
//scan all pixels and down-sample
for(int y=0;ywGapLeft) {
wCount = wGapLeft;
}
if(hCount>hGapLeft) {
hCount = hGapLeft;
}
//count pixels in sample we will make into a pixel (ie 2x2 is 4 pixels , 4x4 is 16 pixels)
final int bytes = getPixelSetCount(2, false, data, flag, origLineLength, y, x, wCount, hCount);
final int inputByte=(x>>2)+(origLineLength*(y<<2));
final int outputByte=(x>>3)+(newLineLength*y);
if(bytes>3){
//set value as white or average of pixels
// final int outputByte=((x>>1) )+(newLineLength*(y>>2));
newData[outputByte] = (byte) (newData[outputByte] | (flag[7-((x & 7))]));
}
}
}
imageData.setWidth(newW);
imageData.setHeight(newH);
data=newData;
sampling=sampling>>1;
}
System.out.println("downSample ="+sampling);
/**/
final int newW = imageData.getWidth() / sampling;
final int newH = imageData.getHeight() / sampling;
final int size = newW * newH;
final byte[] newData = new byte[size];
final int origLineLength = (imageData.getWidth() + 7) >> 3;
//scan all pixels and down-sample
for (int y = 0; y < newH; y++) {
for (int x = 0; x < newW; x++) {
//allow for edges in number of pixels left
int wCount = sampling, hCount = sampling;
final int wGapLeft = imageData.getWidth() - x;
final int hGapLeft = imageData.getHeight() - y;
if (wCount > wGapLeft) {
wCount = wGapLeft;
}
if (hCount > hGapLeft) {
hCount = hGapLeft;
}
//count pixels in sample we will make into a pixel (ie 2x2 is 4 pixels , 4x4 is 16 pixels)
final int bytes = getPixelSetCount(sampling, false, data, flag, origLineLength, y, x, wCount, hCount);
final int count = (wCount * hCount);
//set value as white or average of pixels
final int offset = x + (newW * y);
if (count > 0) {
newData[offset] = (byte) ((255 * bytes) / count);
} else {
newData[offset] = (byte) 255;
}
}
}
imageData.setWidth(newW);
imageData.setHeight(newH);
imageData.setCompCount(1);
//suggest you add kernel sharpening here
//@bethan
//imageData=KernelUtils.sharpenGrayScale(imageData,w,h);
//remap Separation as already converted here
if (decodeColorData.getID() == ColorSpaces.Separation || decodeColorData.getID() == ColorSpaces.DeviceN) {
decodeColorData = new DeviceRGBColorSpace();
imageData.setCompCount(1);
invertBytes(newData);
}
imageData.setObjectData(newData);
imageData.setDepth(8);
return decodeColorData;
}
private static void invertBytes(final byte[] newData) {
final int count = newData.length;
for (int aa = 0; aa < count; aa++) {
newData[aa] = (byte) (newData[aa] ^ 255);
}
}
public static void downsampleTo8Bit(final int sampling, final ImageData imageData, final boolean isMask) {
final byte[] data = imageData.getObjectData();
final int newW = imageData.getWidth() / sampling;
final int newH = imageData.getHeight() / sampling;
final int size = newW * newH;
final byte[] newData = new byte[size];
final int[] flag = {1, 2, 4, 8, 16, 32, 64, 128};
final int origLineLength = (imageData.getWidth() + 7) >> 3;
//scan all pixels and down-sample
for (int y = 0; y < newH; y++) {
for (int x = 0; x < newW; x++) {
//allow for edges in number of pixels left
int wCount = sampling, hCount = sampling;
final int wGapLeft = imageData.getWidth() - x;
final int hGapLeft = imageData.getHeight() - y;
if (wCount > wGapLeft) {
wCount = wGapLeft;
}
if (hCount > hGapLeft) {
hCount = hGapLeft;
}
//count pixels in sample we will make into a pixel (ie 2x2 is 4 pixels , 4x4 is 16 pixels)
final int bytes = getPixelSetCount(sampling, isMask, data, flag, origLineLength, y, x, wCount, hCount);
final int count = (wCount * hCount);
//set value as white or average of pixels
final int offset = x + (newW * y);
if (bytes > 0) {
newData[offset] = (byte) (255 * bytes / count);
}
}
}
imageData.setWidth(newW);
imageData.setHeight(newH);
imageData.setObjectData(newData);
imageData.setDepth(8);
imageData.setCompCount(1);
}
static void convertToARGB(final ImageData imageData, final byte[] maskCol, final boolean scaleTransparency) {
final byte[] data = imageData.getObjectData();
final int newW = imageData.getWidth();
final int newH = imageData.getHeight();
final int size = newW * newH * 4;
final byte[] newData = new byte[size];
//scan all pixels and down-sample
for (int y = 0; y < newH; y++) {
for (int x = 0; x < newW; x++) {
//set value as white or average of pixels
final int offset = x + (newW * y);
final int bytes = data[offset] & 255;
int ptr = 4;
if (bytes < 128) {
ptr = 0;
}
System.arraycopy(maskCol, 0 + ptr, newData, (offset * 4) + 0, 3);
if (scaleTransparency) {
newData[(offset * 4) + 3] = (byte) (((maskCol[3 + ptr] & 255) * bytes) >> 8);
} else {
newData[(offset * 4) + 3] = maskCol[3 + ptr];
}
}
}
imageData.setWidth(newW);
imageData.setHeight(newH);
imageData.setObjectData(newData);
imageData.setDepth(8);
}
private static int getPixelSetCount(final int sampling, final boolean imageMask, final byte[] data, final int[] flag, final int origLineLength,
final int y, final int x, final int wCount, final int hCount) {
byte currentByte;
int bit;
int bytes = 0;
int ptr;
for (int yy = 0; yy < hCount; yy++) {
for (int xx = 0; xx < wCount; xx++) {
ptr = ((yy + (y * sampling)) * origLineLength) + (((x * sampling) + xx) >> 3);
if (ptr < data.length) {
currentByte = data[ptr];
} else {
currentByte = 0;
}
if (imageMask) {
currentByte = (byte) (currentByte ^ 255);
}
bit = currentByte & flag[7 - (((x * sampling) + xx) & 7)];
if (bit != 0) {
bytes++;
}
}
}
return bytes;
}
public static GenericColorSpace downSample(GenericColorSpace decodeColorData, final byte[] maskCol, final int sampling, final ImageData imageData) {
byte[] index = decodeColorData.getIndexedMap();
final boolean needsSharpening = (SamplingFactory.kernelSharpen
|| SamplingFactory.downsampleLevel == SamplingFactory.mediumAndSharpen
|| SamplingFactory.downsampleLevel == SamplingFactory.highAndSharpen);
byte[] colIndex = null;
boolean scaleTransparency = true;
boolean isMask = false;
if (index != null) {
index = decodeColorData.convertIndexToRGB(index);
colIndex = new byte[]{index[0], index[1], index[2], (byte) 255, index[3], index[4], index[5], (byte) 255};
decodeColorData = new DeviceRGBColorSpace();
scaleTransparency = false;
} else if (maskCol != null) {
isMask = true;
colIndex = new byte[]{0, 0, 0, (byte) 255, maskCol[0], maskCol[1], maskCol[2], (byte) 255};
}
if (colIndex != null) {
OneBitDownSampler.downsampleTo8Bit(sampling, imageData, isMask);
if (needsSharpening && sampling < 8) {
KernelUtils.applyKernel(imageData, 1);
}
OneBitDownSampler.convertToARGB(imageData, colIndex, scaleTransparency);
imageData.setIsConvertedToARGB(true);
} else {
decodeColorData = OneBitDownSampler.downSample(sampling, imageData, decodeColorData);
imageData.setImageType(PdfImageTypes.Binary);
if (needsSharpening && sampling < 8) {
KernelUtils.applyKernel(imageData, 1);
}
}
return decodeColorData;
}
}
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