org.apache.commons.imaging.formats.pnm.PbmWriter Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.imaging.formats.pnm;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.charset.StandardCharsets;
import org.apache.commons.imaging.ImageWriteException;
class PbmWriter implements PnmWriter {
private final boolean rawBits;
PbmWriter(final boolean rawBits) {
this.rawBits = rawBits;
}
@Override
public void writeImage(final BufferedImage src, final OutputStream os, final PnmImagingParameters params)
throws ImageWriteException, IOException {
os.write(PnmConstants.PNM_PREFIX_BYTE);
os.write(rawBits ? PnmConstants.PBM_RAW_CODE : PnmConstants.PBM_TEXT_CODE);
os.write(PnmConstants.PNM_SEPARATOR);
final int width = src.getWidth();
final int height = src.getHeight();
os.write(Integer.toString(width).getBytes(StandardCharsets.US_ASCII));
os.write(PnmConstants.PNM_SEPARATOR);
os.write(Integer.toString(height).getBytes(StandardCharsets.US_ASCII));
os.write(PnmConstants.PNM_NEWLINE);
int bitcache = 0;
int bitsInCache = 0;
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
final int argb = src.getRGB(x, y);
final int red = 0xff & (argb >> 16);
final int green = 0xff & (argb >> 8);
final int blue = 0xff & (argb >> 0);
int sample = (red + green + blue) / 3;
if (sample > 127) {
sample = 0;
} else {
sample = 1;
}
if (rawBits) {
bitcache = (bitcache << 1) | (0x1 & sample);
bitsInCache++;
if (bitsInCache >= 8) {
os.write((byte) bitcache);
bitcache = 0;
bitsInCache = 0;
}
} else {
os.write(Integer.toString(sample).getBytes(StandardCharsets.US_ASCII)); // max
// component
// value
os.write(PnmConstants.PNM_SEPARATOR);
}
}
if (rawBits && (bitsInCache > 0)) {
bitcache = bitcache << (8 - bitsInCache);
os.write((byte) bitcache);
bitcache = 0;
bitsInCache = 0;
}
}
}
}