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Commit bce9e5af authored by Vojtech Moravec's avatar Vojtech Moravec
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Moved vector quantization compression to separate file.

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src/main/java/azgracompress/compression/ImageCompressor.java
+ 11
− 89
View file @ bce9e5af
package azgracompress.compression;
import azgracompress.cli.ParsedCliOptions;
import azgracompress.data.Chunk2D;
import azgracompress.data.ImageU16;
import azgracompress.data.V2i;
import azgracompress.fileformat.QCMPFileHeader;
import azgracompress.io.OutBitStream;
import azgracompress.io.RawDataIO;
import azgracompress.quantization.vector.CodebookEntry;
import azgracompress.quantization.vector.LBGResult;
import azgracompress.quantization.vector.LBGVectorQuantizer;
import azgracompress.quantization.vector.VectorQuantizer;
import java.io.BufferedOutputStream;
import java.io.DataOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
public class ImageCompressor extends CompressorDecompressorBase {
......@@ -32,96 +22,37 @@ public class ImageCompressor extends CompressorDecompressorBase {
Log(String.format("Compression with BPP = %d", options.getBitsPerPixel()));
FileOutputStream fos = new FileOutputStream(options.getOutputFile(), false);
DataOutputStream dataOutputStream = new DataOutputStream(new BufferedOutputStream(fos, 8192));
DataOutputStream compressStream = new DataOutputStream(new BufferedOutputStream(fos, 8192));
// Create and write header to output stream.
final QCMPFileHeader header = createHeader();
header.writeHeader(dataOutputStream);
header.writeHeader(compressStream);
boolean compressionResult = true;
switch (options.getQuantizationType()) {
case Scalar: {
SQImageCompressor compressor = new SQImageCompressor(options);
compressor.compress(dataOutputStream);
compressor.compress(compressStream);
}
break;
case Vector1D:
case Vector2D:
compressUsingVectorQuantization(dataOutputStream);
break;
case Vector2D: {
VQImageCompressor compressor = new VQImageCompressor(options);
compressor.compress(compressStream);
}
break;
case Vector3D:
case Invalid:
throw new Exception("Not supported quantization type");
}
dataOutputStream.flush();
compressStream.flush();
fos.flush();
dataOutputStream.close();
compressStream.close();
fos.close();
}
private int[][] getPlaneVectors(final ImageU16 plane) {
final V2i qVector = options.getVectorDimension();
if (qVector.getY() > 1) {
// 2D Quantization.
return Chunk2D.chunksAsImageVectors(plane.as2dChunk().divideIntoChunks(qVector));
} else {
// 1D Quantization.
return plane.as2dChunk().divideInto1DVectors(qVector.getX());
}
}
private VectorQuantizer trainVectorQuantizerFromPlaneVectors(final int[][] planeVectors) {
LBGVectorQuantizer vqInitializer = new LBGVectorQuantizer(planeVectors, codebookSize);
LBGResult vqResult = vqInitializer.findOptimalCodebook(false);
// TODO(Moravec): If verbose ask initializer for result.
return new VectorQuantizer(vqResult.getCodebook());
}
private void compressUsingVectorQuantization(DataOutputStream compressStream) throws Exception {
VectorQuantizer quantizer = null;
if (options.hasReferencePlaneIndex()) {
final ImageU16 referencePlane = RawDataIO.loadImageU16(options.getInputFile(),
options.getImageDimension(),
options.getReferencePlaneIndex());
Log("Creating codebook from reference plane...");
final int[][] refPlaneVectors = getPlaneVectors(referencePlane);
quantizer = trainVectorQuantizerFromPlaneVectors(refPlaneVectors);
writeCodebookToOutputStream(quantizer, compressStream);
Log("Wrote reference codebook.");
}
final int[] planeIndices = getPlaneIndicesForCompression();
for (final int planeIndex : planeIndices) {
Log(String.format("Loading plane %d...", planeIndex));
final ImageU16 plane = RawDataIO.loadImageU16(options.getInputFile(),
options.getImageDimension(),
planeIndex);
final int[][] planeVectors = getPlaneVectors(plane);
if (!options.hasReferencePlaneIndex()) {
Log("Creating plane codebook...");
quantizer = trainVectorQuantizerFromPlaneVectors(planeVectors);
writeCodebookToOutputStream(quantizer, compressStream);
Log("Wrote plane codebook.");
}
assert (quantizer != null);
Log("Writing quantization indices...");
final int[] indices = quantizer.quantizeIntoIndices(planeVectors);
OutBitStream outBitStream = new OutBitStream(compressStream, options.getBitsPerPixel(), 2048);
outBitStream.write(indices);
outBitStream.flush();
Log(String.format("Finished processing of plane %d", planeIndex));
}
}
private QCMPFileHeader createHeader() {
QCMPFileHeader header = new QCMPFileHeader();
......@@ -144,14 +75,5 @@ public class ImageCompressor extends CompressorDecompressorBase {
return header;
}
private void writeCodebookToOutputStream(final VectorQuantizer quantizer,
DataOutputStream compressStream) throws IOException {
final CodebookEntry[] codebook = quantizer.getCodebook();
for (final CodebookEntry entry : codebook) {
final int[] entryVector = entry.getVector();
for (final int vecVal : entryVector) {
compressStream.writeShort(vecVal);
}
}
}
}
src/main/java/azgracompress/compression/SQImageCompressor.java
+ 1
− 1
View file @ bce9e5af
......@@ -46,7 +46,7 @@ public class SQImageCompressor extends CompressorDecompressorBase {
}
/**
* Compress the image file specified by parsed CLI options using scalar quantization..
* Compress the image file specified by parsed CLI options using scalar quantization.
*
* @param compressStream Stream to which compressed data will be written.
* @throws Exception When compress process fails.
......
src/main/java/azgracompress/compression/VQImageCompressor.java
+ 118
− 1
View file @ bce9e5af
package azgracompress.compression;
public class VQImageCompressor {
import azgracompress.cli.ParsedCliOptions;
import azgracompress.data.Chunk2D;
import azgracompress.data.ImageU16;
import azgracompress.data.V2i;
import azgracompress.io.OutBitStream;
import azgracompress.io.RawDataIO;
import azgracompress.quantization.vector.CodebookEntry;
import azgracompress.quantization.vector.LBGResult;
import azgracompress.quantization.vector.LBGVectorQuantizer;
import azgracompress.quantization.vector.VectorQuantizer;
import java.io.DataOutputStream;
import java.io.IOException;
public class VQImageCompressor extends CompressorDecompressorBase {
public VQImageCompressor(ParsedCliOptions options) {
super(options);
}
/**
* Get image vectors from the plane. Vector dimensions are specified by parsed CLI options.
*
* @param plane Image plane.
* @return Image vectors.
*/
private int[][] getPlaneVectors(final ImageU16 plane) {
final V2i qVector = options.getVectorDimension();
if (qVector.getY() > 1) {
// 2D Quantization, return `matrices`.
return Chunk2D.chunksAsImageVectors(plane.as2dChunk().divideIntoChunks(qVector));
} else {
// 1D Quantization, return row vectors.
return plane.as2dChunk().divideInto1DVectors(qVector.getX());
}
}
/**
* Train vector quantizer from plane vectors.
*
* @param planeVectors Image vectors.
* @return Trained vector quantizer with codebook of set size.
*/
private VectorQuantizer trainVectorQuantizerFromPlaneVectors(final int[][] planeVectors) {
LBGVectorQuantizer vqInitializer = new LBGVectorQuantizer(planeVectors, codebookSize);
LBGResult vqResult = vqInitializer.findOptimalCodebook(false);
return new VectorQuantizer(vqResult.getCodebook());
}
/**
* Write the vector codebook to the compress stream.
*
* @param quantizer Quantizer with the codebook.
* @param compressStream Stream with compressed data.
* @throws IOException When unable to write quantizer.
*/
private void writeQuantizerToCompressStream(final VectorQuantizer quantizer,
DataOutputStream compressStream) throws IOException {
final CodebookEntry[] codebook = quantizer.getCodebook();
for (final CodebookEntry entry : codebook) {
final int[] entryVector = entry.getVector();
for (final int vecVal : entryVector) {
compressStream.writeShort(vecVal);
}
}
}
/**
* Compress the image file specified by parsed CLI options using vector quantization.
*
* @param compressStream Stream to which compressed data will be written.
* @throws Exception When compress process fails.
*/
public void compress(DataOutputStream compressStream) throws Exception {
VectorQuantizer quantizer = null;
if (options.hasReferencePlaneIndex()) {
final ImageU16 referencePlane = RawDataIO.loadImageU16(options.getInputFile(),
options.getImageDimension(),
options.getReferencePlaneIndex());
Log("Creating codebook from reference plane...");
final int[][] refPlaneVectors = getPlaneVectors(referencePlane);
quantizer = trainVectorQuantizerFromPlaneVectors(refPlaneVectors);
writeQuantizerToCompressStream(quantizer, compressStream);
Log("Wrote reference codebook.");
}
final int[] planeIndices = getPlaneIndicesForCompression();
for (final int planeIndex : planeIndices) {
Log(String.format("Loading plane %d...", planeIndex));
final ImageU16 plane = RawDataIO.loadImageU16(options.getInputFile(),
options.getImageDimension(),
planeIndex);
final int[][] planeVectors = getPlaneVectors(plane);
if (!options.hasReferencePlaneIndex()) {
Log("Creating plane codebook...");
quantizer = trainVectorQuantizerFromPlaneVectors(planeVectors);
writeQuantizerToCompressStream(quantizer, compressStream);
Log("Wrote plane codebook.");
}
assert (quantizer != null);
Log("Writing quantization indices...");
final int[] indices = quantizer.quantizeIntoIndices(planeVectors);
OutBitStream outBitStream = new OutBitStream(compressStream, options.getBitsPerPixel(), 2048);
outBitStream.write(indices);
outBitStream.flush();
Log(String.format("Finished processing of plane %d", planeIndex));
}
}
}
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