#694 BMP: Fixed subsampling for 24 bit/pixel case

This commit is contained in:
Harald Kuhr 2022-08-16 13:56:51 +02:00
parent 4170b393fa
commit a5c52a99b4
2 changed files with 39 additions and 30 deletions

View File

@ -30,22 +30,6 @@
package com.twelvemonkeys.imageio.plugins.bmp;
import com.twelvemonkeys.imageio.ImageReaderBase;
import com.twelvemonkeys.imageio.stream.SubImageInputStream;
import com.twelvemonkeys.imageio.util.IIOUtil;
import com.twelvemonkeys.imageio.util.ImageTypeSpecifiers;
import com.twelvemonkeys.imageio.util.ProgressListenerBase;
import com.twelvemonkeys.io.LittleEndianDataInputStream;
import com.twelvemonkeys.io.enc.DecoderStream;
import com.twelvemonkeys.xml.XMLSerializer;
import javax.imageio.*;
import javax.imageio.event.IIOReadUpdateListener;
import javax.imageio.event.IIOReadWarningListener;
import javax.imageio.metadata.IIOMetadata;
import javax.imageio.metadata.IIOMetadataFormatImpl;
import javax.imageio.spi.ImageReaderSpi;
import javax.imageio.stream.ImageInputStream;
import java.awt.*;
import java.awt.color.ColorSpace;
import java.awt.image.*;
@ -56,6 +40,27 @@ import java.nio.ByteOrder;
import java.util.Collections;
import java.util.Iterator;
import javax.imageio.IIOException;
import javax.imageio.ImageIO;
import javax.imageio.ImageReadParam;
import javax.imageio.ImageReader;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.event.IIOReadUpdateListener;
import javax.imageio.event.IIOReadWarningListener;
import javax.imageio.metadata.IIOMetadata;
import javax.imageio.metadata.IIOMetadataFormatImpl;
import javax.imageio.spi.ImageReaderSpi;
import javax.imageio.stream.ImageInputStream;
import com.twelvemonkeys.imageio.ImageReaderBase;
import com.twelvemonkeys.imageio.stream.SubImageInputStream;
import com.twelvemonkeys.imageio.util.IIOUtil;
import com.twelvemonkeys.imageio.util.ImageTypeSpecifiers;
import com.twelvemonkeys.imageio.util.ProgressListenerBase;
import com.twelvemonkeys.io.LittleEndianDataInputStream;
import com.twelvemonkeys.io.enc.DecoderStream;
import com.twelvemonkeys.xml.XMLSerializer;
/**
* ImageReader for Microsoft Windows Bitmap (BMP) format.
*
@ -77,7 +82,7 @@ public final class BMPImageReader extends ImageReaderBase {
super(new BMPImageReaderSpi());
}
protected BMPImageReader(final ImageReaderSpi pProvider) {
BMPImageReader(final ImageReaderSpi pProvider) {
super(pProvider);
}
@ -358,14 +363,18 @@ public final class BMPImageReader extends ImageReaderBase {
processImageStarted(imageIndex);
for (int y = 0; y < height; y++) {
switch (header.getBitCount()) {
int bitCount = header.getBitCount();
switch (bitCount) {
case 1:
case 2:
case 4:
case 8:
case 24:
byte[] rowDataByte = ((DataBufferByte) rowRaster.getDataBuffer()).getData();
readRowByte(input, height, srcRegion, xSub, ySub, rowDataByte, destRaster, clippedRow, y);
int bitsPerSample = bitCount == 24 ? 8 : bitCount;
int samplesPerPixel = bitCount == 24 ? 3 : 1;
readRowByte(input, height, srcRegion, xSub, ySub, bitsPerSample, samplesPerPixel, rowDataByte, destRaster, clippedRow, y);
break;
case 16:
@ -379,7 +388,7 @@ public final class BMPImageReader extends ImageReaderBase {
break;
default:
throw new AssertionError("Unsupported pixel depth: " + header.getBitCount());
throw new AssertionError("Unsupported pixel depth: " + bitCount);
}
processImageProgress(100f * y / height);
@ -476,6 +485,7 @@ public final class BMPImageReader extends ImageReaderBase {
}
private void readRowByte(final DataInput input, final int height, final Rectangle srcRegion, final int xSub, final int ySub,
int bitsPerSample, int samplesPerPixel,
final byte[] rowDataByte, final WritableRaster destChannel, final Raster srcChannel, final int y) throws IOException {
// Flip into position?
int srcY = !header.topDown ? height - 1 - y : y;
@ -492,9 +502,7 @@ public final class BMPImageReader extends ImageReaderBase {
// Subsample horizontal
if (xSub != 1) {
for (int x = 0; x < srcRegion.width / xSub; x++) {
rowDataByte[srcRegion.x + x] = rowDataByte[srcRegion.x + x * xSub];
}
IIOUtil.subsampleRow(rowDataByte, srcRegion.x, srcRegion.width, rowDataByte, 0, samplesPerPixel, bitsPerSample, xSub);
}
destChannel.setDataElements(0, dstY, srcChannel);

View File

@ -30,18 +30,19 @@
package com.twelvemonkeys.imageio.plugins.bmp;
import com.twelvemonkeys.imageio.spi.ImageReaderSpiBase;
import static com.twelvemonkeys.imageio.util.IIOUtil.lookupProviderByName;
import javax.imageio.ImageReader;
import javax.imageio.spi.ImageReaderSpi;
import javax.imageio.spi.ServiceRegistry;
import javax.imageio.stream.ImageInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.Locale;
import static com.twelvemonkeys.imageio.util.IIOUtil.lookupProviderByName;
import javax.imageio.ImageReader;
import javax.imageio.spi.ImageReaderSpi;
import javax.imageio.spi.ServiceRegistry;
import javax.imageio.stream.ImageInputStream;
import com.twelvemonkeys.imageio.spi.ImageReaderSpiBase;
/**
* BMPImageReaderSpi
@ -116,7 +117,7 @@ public final class BMPImageReaderSpi extends ImageReaderSpiBase {
}
}
public ImageReader createReaderInstance(final Object pExtension) throws IOException {
public ImageReader createReaderInstance(final Object pExtension) {
return new BMPImageReader(this);
}