IDAT [chunk size] [compressed data] [checksum]
* IDAT [chunk size] [compressed data] [checksum] ...
* This stream class expects an input stream where the first IDAT chunk name and chunk
* size have been read already, the stream is thus pointing to the
* first byte of the first [compressed data] section.
* The size of that section is given to the constructor.
* This class then returns calls to read(), counts the bytes it has given
* away and, whenever a compressed data section has been consumed, it reads
* the IDAT chunk and stores its size, using it to determine when the
* next compressed data section will end.
* That way, for the caller the stream appears to be one large compressed
* section.
* * According to the PNG specs the reason for multiple IDAT chunks is as * follows: *
* (Multiple IDAT chunks are allowed so that encoders can work in a fixed * amount of memory; typically the chunk size will correspond to the encoder's * buffer size.) ** 4.1.3. IDAT Image data *
* If there is a more elegant approach to read multiple IDAT chunks, please * let me know. * However, reading everything into memory is not an option. * @author Marco Schmidt * @since 0.12.0 */ class PngIdatInputStream extends InputStream { private static final int IDAT = 0x49444154; private DataInputStream in; private long bytesLeft; public PngIdatInputStream(DataInputStream input, long bytes) { in = input; bytesLeft = bytes; } public int read() throws IOException { if (bytesLeft == 0) { skipHeaders(); } bytesLeft--; return in.read(); } private void skipHeaders() throws IOException { do { //int crc = in.readInt(); in.readInt(); // skip CRC bytesLeft = in.readInt() & 0xffffffffL; int type = in.readInt(); if (IDAT != type) { throw new IOException("Expected IDAT chunk type, got " + Integer.toHexString(type)); } } while (bytesLeft == 0); } } /** * A codec for the Portable Network Graphics (PNG) format. * Supports both loading and saving of images. *
PNGCodec codec = new PNGCodec();
* codec.setFile("image.png", CodecMode.LOAD);
* codec.process();
* PixelImage image = codec.getImage();
* PNGCodec codec = new PNGCodec();
* codec.setFile("out.png", CodecMode.SAVE);
* codec.setImage(image);
* codec.setCompressionLevel(Deflater.BEST_COMPRESSION);
* codec.appendComment("Copyright (c) 1992 John Doe");
* // sets last modification time to current time
* codec.setModification(new GregorianCalendar(
* new SimpleTimeZone(0, "UTC")));
* codec.process();
* pHYs chunks.
* Use {@link #getDpiX} and {@link #getDpiY} to retrieve that information.
* after the call to {@link #process}.tEXt chunks and can be retrieved
* with {@link #getComment} after the call to {@link #process}.pHYs chunk.tEXt chunks.
* The keyword used is Comment.
* Each of the {@link #getNumComments} is stored in a chunk of its own.tIME chunk.
* Use {@link #setModification(Calendar)} to give a point in time to this codec.image,
* taking into consideration the fields width, height, precision and colorType.
* Assumes that an IHDR chunk has been read and the above mentioned
* fields have been initialized and checked for their validity.
*/
private void allocateImage() throws InvalidFileStructureException, UnsupportedTypeException
{
setBoundsIfNecessary(width, height);
int w = getBoundsWidth();
int h = getBoundsHeight();
if (colorType == COLOR_TYPE_GRAY || colorType == COLOR_TYPE_GRAY_ALPHA)
{
if (precision == 1)
{
image = new MemoryBilevelImage(w, h);
}
else
if (precision <= 8)
{
image = new MemoryGray8Image(w, h);
}
else
if (precision == 16)
{
image = new MemoryGray16Image(w, h);
}
}
else
if (colorType == COLOR_TYPE_INDEXED)
{
if (palette == null)
{
throw new InvalidFileStructureException("No palette found when trying to load indexed image.");
}
image = new MemoryPaletted8Image(w, h, palette);
}
else
if (colorType == COLOR_TYPE_RGB || colorType == COLOR_TYPE_RGB_ALPHA)
{
if (precision == 8)
{
image = new MemoryRGB24Image(w, h);
}
else
{
image = new MemoryRGB48Image(w, h);
}
}
else
{
throw new UnsupportedTypeException("Unsupported image type encountered");
}
}
/**
* Checks values {@link #precision} and {@link #colorType}.
* A lot of combinations possibly found in an IHDR chunk
* are invalid.
* Also initializes {@link #alpha} and {@link #numChannels}.
* @throws UnsupportedTypeException if an invalid combination
* of precision and colorType is found
*/
private void checkColorTypeAndPrecision() throws UnsupportedTypeException
{
if (colorType != COLOR_TYPE_GRAY &&
colorType != COLOR_TYPE_RGB &&
colorType != COLOR_TYPE_INDEXED &&
colorType != COLOR_TYPE_GRAY_ALPHA &&
colorType != COLOR_TYPE_RGB_ALPHA)
{
throw new UnsupportedTypeException("Not a valid color type: " + colorType);
}
if (precision != 1 && precision != 2 && precision != 4 && precision != 8 && precision != 16)
{
throw new UnsupportedTypeException("Invalid precision value: " + precision);
}
if (colorType == COLOR_TYPE_INDEXED && precision > 8)
{
throw new UnsupportedTypeException("More than eight bits of precision are not allowed for indexed images.");
}
if (colorType == COLOR_TYPE_RGB && precision < 8)
{
throw new UnsupportedTypeException("Less than eight bits of precision are not allowed for RGB images.");
}
alpha = (colorType & COLOR_TYPE_ALPHA) != 0;
if (colorType == COLOR_TYPE_RGB ||
colorType == COLOR_TYPE_RGB_ALPHA)
{
numChannels = 3;
}
else
{
numChannels = 1;
}
bpp = computeBytesPerRow(1);
}
/**
* Computes a number of bytes for a given number of pixels,
* regarding precision and availability of an alpha channel.
* @param numPixels the number of pixels for which the number
* of bytes necessary to store them is to be computed
* @return number of bytes
*/
private int computeBytesPerRow(int numPixels)
{
if (precision < 8)
{
return (numPixels + ((8 / precision) - 1)) / (8 / precision);
}
else
{
return (numChannels + (alpha ? 1 : 0)) * (precision / 8) * numPixels;
}
}
private int computeColumnsAdam7(int pass)
{
switch(pass)
{
case(0): return (width + 7) / 8;
case(1): return (width + 3) / 8;
case(2): return (width + 3) / 4;
case(3): return (width + 1) / 4;
case(4): return (width + 1) / 2;
case(5): return width / 2;
case(6): return width;
default: throw new IllegalArgumentException("Not a valid pass index: " + pass);
}
}
private void fillRowBuffer(int y, byte[] row, int offs)
{
PixelImage image = getImage();
int x1 = getBoundsX1();
int w = getBoundsWidth();
if (image instanceof BilevelImage)
{
BilevelImage bilevelImage = (BilevelImage)image;
bilevelImage.getPackedBytes(x1, y, w, row, offs, 0);
}
else
if (image instanceof Gray16Image)
{
Gray16Image grayImage = (Gray16Image)image;
while (w-- > 0)
{
short sample = grayImage.getShortSample(x1++, y);
ArrayConverter.setShortBE(row, offs, sample);
offs += 2;
}
}
else
if (image instanceof Gray8Image)
{
Gray8Image grayImage = (Gray8Image)image;
grayImage.getByteSamples(0, getBoundsX1(), y, getBoundsWidth(), 1, row, offs);
}
else
if (image instanceof Paletted8Image)
{
Paletted8Image palImage = (Paletted8Image)image;
palImage.getByteSamples(0, getBoundsX1(), y, getBoundsWidth(), 1, row, offs);
}
else
if (image instanceof RGB24Image)
{
RGB24Image rgbImage = (RGB24Image)image;
while (w-- > 0)
{
row[offs++] = rgbImage.getByteSample(RGBIndex.INDEX_RED, x1, y);
row[offs++] = rgbImage.getByteSample(RGBIndex.INDEX_GREEN, x1, y);
row[offs++] = rgbImage.getByteSample(RGBIndex.INDEX_BLUE, x1, y);
x1++;
}
}
else
if (image instanceof RGB48Image)
{
RGB48Image rgbImage = (RGB48Image)image;
while (w-- > 0)
{
short sample = rgbImage.getShortSample(RGBIndex.INDEX_RED, x1, y);
ArrayConverter.setShortBE(row, offs, sample);
offs += 2;
sample = rgbImage.getShortSample(RGBIndex.INDEX_GREEN, x1, y);
ArrayConverter.setShortBE(row, offs, sample);
offs += 2;
sample = rgbImage.getShortSample(RGBIndex.INDEX_BLUE, x1, y);
ArrayConverter.setShortBE(row, offs, sample);
offs += 2;
x1++;
}
}
}
/**
* Creates a four-letter String from the parameter, an int
* value, supposed to be storing a chunk name.
* @return the chunk name
*/
private static String getChunkName(int chunk)
{
StringBuffer result = new StringBuffer(4);
for (int i = 24; i >= 0; i -= 8)
{
result.append((char)((chunk >> i) & 0xff));
}
return result.toString();
}
public String getFormatName()
{
return "Portable Network Graphics (PNG)";
}
public String[] getMimeTypes()
{
return new String[] {"image/png"};
}
private static int getPaeth(byte l, byte u, byte nw)
{
int a = l & 0xff;
int b = u & 0xff;
int c = nw & 0xff;
int p = a + b - c;
int pa = p - a;
if (pa < 0)
{
pa = -pa;
}
int pb = p - b;
if (pb < 0)
{
pb = -pb;
}
int pc = p - c;
if (pc < 0)
{
pc = -pc;
}
if (pa <= pb && pa <= pc)
{
return a;
}
if (pb <= pc)
{
return b;
}
return c;
}
private void inflateBytes(byte[] buffer, int numBytes) throws InvalidFileStructureException, IOException
{
int offset = 0;
do
{
try
{
int toRead = numBytes - offset;
int numRead = infl.read(buffer, offset, toRead);
if (numRead < 0)
{
throw new InvalidFileStructureException("Cannot fill buffer");
}
offset += numRead;
}
catch (IOException ioe)
{
throw new InvalidFileStructureException("Stopped decompressing " + ioe.toString());
}
}
while (offset != numBytes);
}
public boolean isLoadingSupported()
{
return true;
}
public boolean isSavingSupported()
{
return true;
}
private void load() throws
InvalidFileStructureException,
IOException,
UnsupportedTypeException,
WrongFileFormatException
{
byte[] magic = new byte[MAGIC_BYTES.length];
in.readFully(magic);
for (int i = 0; i < MAGIC_BYTES.length; i++)
{
if (magic[i] != MAGIC_BYTES[i])
{
throw new WrongFileFormatException("Not a valid PNG input " +
"stream, wrong magic byte sequence.");
}
}
chunkCounter = 0;
do
{
loadChunk();
chunkCounter++;
}
while (image == null);
close();
setImage(image);
}
private void loadChunk() throws InvalidFileStructureException, IOException, UnsupportedTypeException
{
/*
* read chunk size; according to the PNG specs, the size value must not be larger
* than 2^31 - 1; to be safe, we treat the value as an unsigned
* 32 bit value anyway
*/
long chunkSize = in.readInt() & 0xffffffffL;
checksum.reset();
int chunkName = in.readInt();
// first chunk must be IHDR
if (chunkCounter == 0 && chunkName != CHUNK_TYPE_IHDR)
{
throw new InvalidFileStructureException("First chunk was not IHDR but " + getChunkName(chunkName));
}
switch (chunkName)
{
// image data chunk
case(CHUNK_TYPE_IDAT):
{
loadImage(chunkSize);
break;
}
// end of image chunk
case(CHUNK_TYPE_IEND):
{
throw new InvalidFileStructureException("Reached IEND chunk but could not load image.");
}
case(CHUNK_TYPE_IHDR):
{
if (hasIhdr)
{
throw new InvalidFileStructureException("More than one IHDR chunk found.");
}
if (chunkCounter != 0)
{
throw new InvalidFileStructureException("IHDR chunk must be first; found to be chunk #" + (chunkCounter + 1));
}
if (chunkSize != CHUNK_SIZE_IHDR)
{
throw new InvalidFileStructureException("Expected PNG " +
"IHDR chunk length to be " + CHUNK_SIZE_IHDR + ", got " +
chunkSize + ".");
}
hasIhdr = true;
loadImageHeader();
break;
}
case(CHUNK_TYPE_PHYS):
{
if (chunkSize == 9)
{
byte[] phys = new byte[9];
in.readFully(phys);
int x = ArrayConverter.getIntBE(phys, 0);
int y = ArrayConverter.getIntBE(phys, 4);
if (phys[8] == 1)
{
// unit is meters
final double INCHES_PER_METER = 100 / 2.54;
setDpi((int)(x / INCHES_PER_METER), (int)(y / INCHES_PER_METER));
}
}
else
{
skip(chunkSize);
}
break;
}
case(CHUNK_TYPE_PLTE):
{
if ((chunkSize % 3) != 0)
{
throw new InvalidFileStructureException("Not a valid palette chunk size: " + chunkSize);
}
loadPalette(chunkSize / 3);
break;
}
case(CHUNK_TYPE_TEXT):
{
if (chunkSize == 0)
{
}
else
if (chunkSize > MAX_TEXT_SIZE)
{
skip(chunkSize);
}
else
{
StringBuffer text = new StringBuffer((int)chunkSize);
int i = 0;
char c;
do
{
c = (char)in.read();
if (c == 0)
{
skip(chunkSize - i - 1);
break;
}
text.append(c);
i++;
}
while (i < chunkSize);
//System.out.println("text=\"" + text.toString() + "\"");
}
break;
}
default:
{
skip(chunkSize);
}
}
int createdChecksum = (int)checksum.getValue();
if (image == null)
{
// this code doesn't work anymore if we have just read an image
int chunkChecksum = in.readInt();
if (createdChecksum != chunkChecksum)
{
throw new InvalidFileStructureException("Checksum created on chunk " +
getChunkName(chunkName) + " " + Integer.toHexString(createdChecksum) +
" is not equal to checksum read from stream " +
Integer.toHexString(chunkChecksum) +
"; file is corrupted.");
}
}
}
/**
* Load an image from the current position in the file.
* Assumes the last things read from input are an IDAT chunk type and
* its size, which is the sole argument of this method.
* @param chunkSize size of the IDAT chunk that was just read
* @throws InvalidFileStructureException if there are values in the PNG stream that make it invalid
* @throws IOException if there were I/O errors when reading
* @throws UnsupportedTypeException if something was encountered in the stream that is valid but not supported by this codec
*/
private void loadImage(long chunkSize) throws InvalidFileStructureException, IOException, UnsupportedTypeException
{
// allocate two byte buffers for current and previous row
buffers = new byte[2][];
int numBytes = computeBytesPerRow(width);
currentBufferIndex = 0;
previousBufferIndex = 1;
buffers[currentBufferIndex] = new byte[numBytes];
buffers[previousBufferIndex] = new byte[numBytes];
for (int i = 0; i < buffers[previousBufferIndex].length; i++)
{
buffers[previousBufferIndex][i] = (byte)0;
}
// allocate the correct type of image object for the image type read in the IHDR chunk
allocateImage();
// create a PngIdatInputStream which will skip header information when
// multiple IDAT chunks are in the input stream
infl = new InflaterInputStream(new PngIdatInputStream(in, chunkSize));
switch(interlaceType)
{
case(INTERLACING_NONE):
{
loadImageNonInterlaced();
break;
}
case(INTERLACING_ADAM7):
{
loadImageInterlacedAdam7();
break;
}
}
}
/**
* Reads data from an IHDR chunk and initializes private fields with it.
* Does a lot of checking if read values are valid and supported by this class.
* @throws IOException
* @throws InvalidFileStructureException
* @throws UnsupportedTypeException
*/
private void loadImageHeader() throws IOException, InvalidFileStructureException, UnsupportedTypeException
{
// WIDTH -- horizontal resolution
width = in.readInt();
if (width < 1)
{
throw new InvalidFileStructureException("Width must be larger than 0; got " + width);
}
// HEIGHT -- vertical resolution
height = in.readInt();
if (height < 1)
{
throw new InvalidFileStructureException("Height must be larger than 0; got " + height);
}
// PRECISION -- bits per sample
precision = in.read();
// COLOR TYPE -- indexed, paletted, grayscale, optionally alpha
colorType = in.read();
// check for invalid combinations of color type and precision
// and initialize alpha and numChannels
checkColorTypeAndPrecision();
// COMPRESSION TYPE -- only Deflate is defined
compressionType = in.read();
if (compressionType != COMPRESSION_DEFLATE)
{
throw new UnsupportedTypeException("Unsupported compression type: " +
compressionType + ".");
}
// FILTER TYPE -- only Adaptive is defined
filterType = in.read();
if (filterType != FILTERING_ADAPTIVE)
{
throw new UnsupportedTypeException("Only 'adaptive filtering' is supported right now; got " + filterType);
}
// INTERLACE TYPE -- order of storage of image data
interlaceType = in.read();
if (interlaceType != INTERLACING_NONE &&
interlaceType != INTERLACING_ADAM7)
{
throw new UnsupportedTypeException("Only 'no interlacing' and 'Adam7 interlacing' are supported; got " + interlaceType);
}
}
private void loadImageInterlacedAdam7() throws InvalidFileStructureException, IOException, UnsupportedTypeException
{
final int TOTAL_LINES = ADAM7_NUM_PASSES * height;
for (int pass = 0; pass < ADAM7_NUM_PASSES; pass++)
{
currentBufferIndex = 0;
previousBufferIndex = 1;
byte[] previousBuffer = buffers[previousBufferIndex];
for (int x = 0; x < previousBuffer.length; x++)
{
previousBuffer[x] = 0;
}
int y = ADAM7_FIRST_ROW[pass];
int destY = y - getBoundsY1();
int numColumns = computeColumnsAdam7(pass);
if (numColumns == 0)
{
// this pass contains no data; skip to next pass
setProgress((pass + 1) * height, TOTAL_LINES);
continue;
}
int numBytes = computeBytesPerRow(numColumns);
while (y < height)
{
previousBuffer = buffers[previousBufferIndex];
byte[] currentBuffer = buffers[currentBufferIndex];
int rowFilterType = readFilterType();
inflateBytes(currentBuffer, numBytes);
reverseFilter(rowFilterType, currentBuffer, previousBuffer, numBytes);
if (isRowRequired(y))
{
storeInterlacedAdam7(pass, destY, currentBuffer);
}
int progressY = y;
if (pass > 0)
{
progressY += pass * height;
}
setProgress(progressY, TOTAL_LINES);
y += ADAM7_ROW_INCREMENT[pass];
destY += ADAM7_ROW_INCREMENT[pass];
currentBufferIndex = 1 - currentBufferIndex;
previousBufferIndex = 1 - previousBufferIndex;
}
}
}
private void loadImageNonInterlaced() throws InvalidFileStructureException, IOException, UnsupportedTypeException
{
int linesToRead = getBoundsY2() + 1;
int rowLength = computeBytesPerRow(width);
for (int y = 0, destY = - getBoundsY1(); y <= getBoundsY2(); y++, destY++)
{
byte[] currentBuffer = buffers[currentBufferIndex];
byte[] previousBuffer = buffers[previousBufferIndex];
int rowFilterType = readFilterType();
inflateBytes(currentBuffer, rowLength);
reverseFilter(rowFilterType, currentBuffer, previousBuffer, rowLength);
if (isRowRequired(y))
{
storeNonInterlaced(destY, currentBuffer);
}
setProgress(y, linesToRead);
previousBufferIndex = 1 - previousBufferIndex;
currentBufferIndex = 1 - currentBufferIndex;
}
}
private void loadPalette(long numEntries) throws InvalidFileStructureException, IOException
{
if (palette != null)
{
throw new InvalidFileStructureException("More than one palette in input stream.");
}
if (numEntries < 1)
{
throw new InvalidFileStructureException("Number of palette entries must be at least 1.");
}
if (numEntries > 256)
{
throw new InvalidFileStructureException("Number of palette entries larger than 256: " + numEntries);
}
palette = new Palette((int)numEntries);
int index = 0;
do
{
palette.putSample(Palette.INDEX_RED, index, in.read() & 0xff);
palette.putSample(Palette.INDEX_GREEN, index, in.read() & 0xff);
palette.putSample(Palette.INDEX_BLUE, index, in.read() & 0xff);
index++;
}
while (index != numEntries);
}
public static void main(String[] args) throws Exception
{
PNGCodec codec = new PNGCodec();
codec.setFile(args[0], CodecMode.LOAD);
codec.process();
codec.close();
PixelImage image = codec.getImage();
codec = new PNGCodec();
codec.setFile(args[1], CodecMode.SAVE);
codec.setImage(image);
codec.setDpi(300, 300);
codec.appendComment("Test comment #1.");
codec.appendComment("And test comment #2.");
codec.setModification(new GregorianCalendar(new SimpleTimeZone(0, "UTC")));
codec.process();
codec.close();
}
public void process() throws
InvalidFileStructureException,
MissingParameterException,
OperationFailedException,
UnsupportedTypeException,
WrongFileFormatException
{
initModeFromIOObjects();
if (getMode() == CodecMode.LOAD)
{
try
{
if (getImageIndex() != 0)
{
throw new InvalidImageIndexException("PNG streams can only store one image; " +
"index " + getImageIndex() + " is thus not valid.");
}
InputStream input = getInputStream();
if (input == null)
{
throw new MissingParameterException("InputStream object missing.");
}
checksum = new CRC32();
checkedIn = new CheckedInputStream(input, checksum);
in = new DataInputStream(checkedIn);
load();
}
catch (IOException ioe)
{
throw new OperationFailedException("I/O failure: " + ioe.toString());
}
}
else
if (getMode() == CodecMode.SAVE)
{
try
{
PixelImage image = getImage();
if (image == null)
{
throw new MissingParameterException("Need image for saving.");
}
out = getOutputAsDataOutput();
if (out == null)
{
throw new MissingParameterException("Could not retrieve non-null DataOutput object for saving.");
}
setBoundsIfNecessary(image.getWidth(), image.getHeight());
save();
}
catch (IOException ioe)
{
throw new OperationFailedException("I/O failure: " + ioe.toString());
}
}
else
{
throw new OperationFailedException("Unknown codec mode: " + getMode());
}
}
private int readFilterType() throws InvalidFileStructureException, IOException
{
int filterType = infl.read();
if (filterType >= 0 && filterType <= 4)
{
return filterType;
}
else
{
throw new InvalidFileStructureException("Valid filter types are from 0 to 4; got " + filterType);
}
}
private void reverseFilter(int rowFilterType, byte[] buffer, byte[] prev, int numBytes) throws UnsupportedTypeException
{
switch(rowFilterType)
{
case(FILTER_TYPE_NONE):
{
break;
}
case(FILTER_TYPE_SUB):
{
for (int x = 0, px = -bpp; x < numBytes; x++, px++)
{
byte currXMinusBpp;
if (px < 0)
{
currXMinusBpp = 0;
}
else
{
currXMinusBpp = buffer[px];
}
buffer[x] = (byte)(buffer[x] + currXMinusBpp);
}
break;
}
case(FILTER_TYPE_UP):
{
for (int x = 0; x < numBytes; x++)
{
buffer[x] = (byte)(buffer[x] + prev[x]);
}
break;
}
case(FILTER_TYPE_AVERAGE):
{
for (int x = 0, px = -bpp; x < numBytes; x++, px++)
{
int currX = buffer[x] & 0xff;
int currXMinus1;
if (px < 0)
{
currXMinus1 = 0;
}
else
{
currXMinus1 = buffer[px] & 0xff;
}
int prevX = prev[x] & 0xff;
int result = currX + ((currXMinus1 + prevX) / 2);
byte byteResult = (byte)result;
buffer[x] = byteResult;
}
break;
}
case(FILTER_TYPE_PAETH):
{
for (int x = 0, px = -bpp; x < numBytes; x++, px++)
{
byte currXMinusBpp;
byte prevXMinusBpp;
if (px < 0)
{
currXMinusBpp = 0;
prevXMinusBpp = 0;
}
else
{
currXMinusBpp = buffer[px];
prevXMinusBpp = prev[px];
}
buffer[x] = (byte)(buffer[x] + getPaeth(currXMinusBpp, prev[x], prevXMinusBpp));
}
break;
}
default:
{
throw new UnsupportedTypeException("Unknown filter type: " + rowFilterType);
}
}
}
private void save() throws IOException
{
// write 8 byte PNG signature
out.write(MAGIC_BYTES);
// write IHDR (image header) chunk
saveIhdrChunk();
// write pHYs chunk (physical resolution) if data is available
savePhysChunk();
// write tEXt chunks if comments are available
saveTextChunks();
// write tIME chunk if modification time was set
saveTimeChunk();
// write PLTE chunk if necessary
savePlteChunk();
// write IDAT chunk
saveImage();
// write IEND chunk
saveIendChunk();
close();
}
private void saveChunk(int chunkType, int chunkSize, byte[] data) throws IOException
{
// set up array with chunk size and type
byte[] intArray = new byte[8];
ArrayConverter.setIntBE(intArray, 0, chunkSize);
ArrayConverter.setIntBE(intArray, 4, chunkType);
// write chunk size, type and data
out.write(intArray, 0, 8);
out.write(data, 0, chunkSize);
// create checksum on type and data
CRC32 checksum = new CRC32();
checksum.reset();
checksum.update(intArray, 4, 4);
checksum.update(data, 0, chunkSize);
// put checksum into byte array
ArrayConverter.setIntBE(intArray, 0, (int)checksum.getValue());
// and write it to output
out.write(intArray, 0, 4);
}
private void saveIendChunk() throws IOException
{
out.writeInt(0);
out.writeInt(CHUNK_TYPE_IEND);
out.writeInt(CHUNK_CRC32_IEND);
}
private void saveIhdrChunk() throws IOException
{
byte[] buffer = new byte[CHUNK_SIZE_IHDR];
width = getBoundsWidth();
ArrayConverter.setIntBE(buffer, 0, width);
height = getBoundsHeight();
ArrayConverter.setIntBE(buffer, 4, height);
PixelImage image = getImage();
alpha = false;
numChannels = 1;
if (image instanceof BilevelImage)
{
precision = 1;
colorType = COLOR_TYPE_GRAY;
}
else
if (image instanceof Gray16Image)
{
precision = 16;
colorType = COLOR_TYPE_GRAY;
}
else
if (image instanceof Gray8Image)
{
precision = 8;
colorType = COLOR_TYPE_GRAY;
}
else
if (image instanceof Paletted8Image)
{
precision = 8;
colorType = COLOR_TYPE_INDEXED;
}
else
if (image instanceof RGB24Image)
{
numChannels = 3;
precision = 8;
colorType = COLOR_TYPE_RGB;
}
else
if (image instanceof RGB48Image)
{
numChannels = 3;
precision = 16;
colorType = COLOR_TYPE_RGB;
}
buffer[8] = (byte)precision;
buffer[9] = (byte)colorType;
compressionType = COMPRESSION_DEFLATE;
buffer[10] = (byte)compressionType;
filterType = FILTERING_ADAPTIVE;
buffer[11] = (byte)filterType;
interlaceType = INTERLACING_NONE;
buffer[12] = (byte)interlaceType;
saveChunk(CHUNK_TYPE_IHDR, CHUNK_SIZE_IHDR, buffer);
}
private void saveImage() throws IOException
{
switch(interlaceType)
{
case(INTERLACING_NONE):
{
saveImageNonInterlaced();
break;
}
}
}
private void saveImageNonInterlaced() throws IOException
{
int bytesPerRow = computeBytesPerRow(getBoundsWidth());
byte[] rowBuffer = new byte[bytesPerRow + 1];
byte[] outBuffer = new byte[Math.max(encodingMinIdatSize, bytesPerRow + 1)];
int outOffset = 0;
int numDeflated;
Deflater defl = new Deflater(deflateLevel);
defl.setStrategy(deflateStrategy);
for (int y = getBoundsY1(); y <= getBoundsY2(); y++)
{
// fill row buffer
rowBuffer[0] = (byte)FILTER_TYPE_NONE;
fillRowBuffer(y, rowBuffer, 1);
// give it to compressor
defl.setInput(rowBuffer);
// store compressed data in outBuffer
do
{
numDeflated = defl.deflate(outBuffer, outOffset, outBuffer.length - outOffset);
outOffset += numDeflated;
if (outOffset == outBuffer.length)
{
saveChunk(CHUNK_TYPE_IDAT, outOffset, outBuffer);
outOffset = 0;
}
}
while (numDeflated > 0);
setProgress(y - getBoundsY1(), getBoundsHeight());
}
// tell Deflater that it got all the input
defl.finish();
// retrieve remaining compressed data from defl to outBuffer
do
{
numDeflated = defl.deflate(outBuffer, outOffset, outBuffer.length - outOffset);
outOffset += numDeflated;
if (outOffset == outBuffer.length)
{
saveChunk(CHUNK_TYPE_IDAT, outOffset, outBuffer);
outOffset = 0;
}
}
while (numDeflated > 0);
// write final IDAT chunk if necessary
if (outOffset > 0)
{
saveChunk(CHUNK_TYPE_IDAT, outOffset, outBuffer);
}
}
private void savePhysChunk() throws IOException
{
int dpiX = getDpiX();
int dpiY = getDpiY();
if (dpiX < 1 || dpiY < 1)
{
return;
}
byte[] data = new byte[9];
int ppuX = (int)(dpiX * (100 / 2.54));
int ppuY = (int)(dpiY * (100 / 2.54));
ArrayConverter.setIntBE(data, 0, ppuX);
ArrayConverter.setIntBE(data, 4, ppuY);
data[8] = 1; // unit is the meter
saveChunk(CHUNK_TYPE_PHYS, data.length, data);
}
private void savePlteChunk() throws IOException
{
if (colorType != COLOR_TYPE_INDEXED)
{
return;
}
Paletted8Image image = (Paletted8Image)getImage();
Palette pal = image.getPalette();
int numEntries = pal.getNumEntries();
byte[] data = new byte[numEntries * 3];
for (int i = 0, j = 0; i < numEntries; i++, j += 3)
{
data[j] = (byte)pal.getSample(RGBIndex.INDEX_RED, i);
data[j + 1] = (byte)pal.getSample(RGBIndex.INDEX_GREEN, i);
data[j + 2] = (byte)pal.getSample(RGBIndex.INDEX_BLUE, i);
}
saveChunk(CHUNK_TYPE_PLTE, data.length, data);
}
private void saveTextChunks() throws IOException
{
int index = 0;
while (index < getNumComments())
{
String comment = getComment(index++);
comment = "Comment\000" + comment;
byte[] data = comment.getBytes("ISO-8859-1");
saveChunk(CHUNK_TYPE_TEXT, data.length, data);
}
}
private void saveTimeChunk() throws IOException
{
if (modification == null)
{
return;
}
byte[] data = new byte[7];
ArrayConverter.setShortBE(data, 0, (short)modification.get(Calendar.YEAR));
data[2] = (byte)(modification.get(Calendar.MONTH) + 1);
data[3] = (byte)modification.get(Calendar.DAY_OF_MONTH);
data[4] = (byte)modification.get(Calendar.HOUR_OF_DAY);
data[5] = (byte)modification.get(Calendar.MINUTE);
data[6] = (byte)modification.get(Calendar.SECOND);
saveChunk(CHUNK_TYPE_TIME, data.length, data);
}
/**
* Sets the compression level to be used with the underlying
* {@link java.util.zip.Deflater} object which does the compression.
* If no value is specified, {@link java.util.zip.Deflater#DEFAULT_COMPRESSION}
* is used.
* @param newLevel compression level, from 0 to 9, 0 being fastest
* and compressing worst and 9 offering highest compression and taking
* the most time
*/
public void setCompressionLevel(int newLevel)
{
if (newLevel >= 0 && newLevel <= 9)
{
deflateLevel = newLevel;
}
else
{
throw new IllegalArgumentException("Compression level must be from 0..9; got " + newLevel);
}
}
/**
* Sets the compression strategy to be used with the underlying
* {@link java.util.zip.Deflater} object which does the compression.
* If no value is specified, {@link java.util.zip.Deflater#DEFAULT_STRATEGY}
* is used.
* @param newStrategy one of Deflater's strategy values:
* {@link java.util.zip.Deflater#DEFAULT_STRATEGY},
* {@link java.util.zip.Deflater#FILTERED},
* {@link java.util.zip.Deflater#HUFFMAN_ONLY}
*/
public void setCompressionStrategy(int newStrategy)
{
if (newStrategy == Deflater.FILTERED ||
newStrategy == Deflater.DEFAULT_STRATEGY ||
newStrategy == Deflater.HUFFMAN_ONLY)
{
deflateStrategy = newStrategy;
}
else
{
throw new IllegalArgumentException("Unknown compression strategy: " + newStrategy);
}
}
/**
* Sets the size of IDAT chunks generated when encoding.
* If this method is never called, a default value of 32768 bytes (32 KB) is used.
* Note that a byte array of the size of the value you specify here is allocated,
* so make sure that you keep the value small enough to stay within a
* system's memory.
* * Compressed image data is spread over several IDAT chunks by this codec. * The length of the compressed data of a complete image is known only after the complete image * has been encoded. * With PNG, that length value has to be stored before the compressed data as a chunk size value. * This codec is supposed to work with {@link java.io.OutputStream} objects, * so seeking back to adjust the chunk size value of an IDAT chunk is not * possible. * That's why all data of a chunk is compressed into a memory buffer. * Whenever the buffer gets full, it is written to output as an IDAT chunk. *
* Note that the last IDAT chunk may be smaller than the size defined here.
* @param newSize size of encoding compressed data buffer
*/
public void setEncodingIdatSize(int newSize)
{
if (newSize < 1)
{
throw new IllegalArgumentException("Minimum IDAT chunk size must be 1 or larger.");
}
encodingMinIdatSize = newSize;
}
public void setFile(String fileName, CodecMode codecMode) throws IOException, UnsupportedCodecModeException
{
if (codecMode == CodecMode.LOAD)
{
setInputStream(new BufferedInputStream(new FileInputStream(fileName)));
}
else
{
super.setFile(fileName, codecMode);
}
}
/**
* Sets date and time of last modification of the image to be stored in a PNG stream
* when saving.
* Make sure the argument object has UTC as time zone
* (as
* demanded by the PNG specs).
* If you want the current time and date, use
* new GregorianCalendar(new SimpleTimeZone(0, "UTC"))
* as parameter for this method.
* @param time time of last modification of the image
*/
public void setModification(Calendar time)
{
modification = time;
}
/**
* Skips a number of bytes in the input stream.
* @param num number of bytes to be skipped
* @throws IOException if there were I/O errors
*/
private void skip(long num) throws IOException
{
while (num > 0)
{
long numSkipped = in.skip(num);
if (numSkipped > 0)
{
num -= numSkipped;
}
}
}
private void storeInterlacedAdam7(int pass, int y, byte[] buffer)
{
switch(colorType)
{
case(COLOR_TYPE_GRAY):
{
storeInterlacedAdam7Gray(pass, y, buffer);
break;
}
case(COLOR_TYPE_RGB):
{
storeInterlacedAdam7Rgb(pass, y, buffer);
break;
}
case(COLOR_TYPE_RGB_ALPHA):
{
storeInterlacedAdam7RgbAlpha(pass, y, buffer);
break;
}
case(COLOR_TYPE_GRAY_ALPHA):
{
storeInterlacedAdam7GrayAlpha(pass, y, buffer);
break;
}
case(COLOR_TYPE_INDEXED):
{
storeInterlacedAdam7Indexed(pass, y, buffer);
break;
}
}
}
private void storeInterlacedAdam7Gray(int pass, int y, byte[] buffer)
{
int x = ADAM7_FIRST_COLUMN[pass];
final int incr = ADAM7_COLUMN_INCREMENT[pass];
final int x1 = getBoundsX1();
final int x2 = getBoundsX2();
int offset = 0;
int numColumns = computeColumnsAdam7(pass);
int numPackedBytes = computeBytesPerRow(numColumns);
byte[] dest = new byte[numColumns + 7];
switch(precision)
{
case(1):
{
BilevelImage bilevelImage = (BilevelImage)image;
ArrayConverter.decodePacked1Bit(buffer, 0, dest, 0, numPackedBytes);
while (x <= x2)
{
if (x >= x1)
{
if (dest[offset] == 0)
{
bilevelImage.putBlack(x - x1, y);
}
else
{
bilevelImage.putWhite(x - x1, y);
}
}
x += incr;
offset++;
}
break;
}
case(2):
{
Gray8Image grayImage = (Gray8Image)image;
ArrayConverter.convertPacked2BitIntensityTo8Bit(buffer, 0, dest, 0, numPackedBytes);
while (x <= x2)
{
if (x >= x1)
{
grayImage.putByteSample(x - x1, y, dest[offset]);
}
x += incr;
offset++;
}
break;
}
case(4):
{
Gray8Image grayImage = (Gray8Image)image;
ArrayConverter.convertPacked4BitIntensityTo8Bit(buffer, 0, dest, 0, numPackedBytes);
while (x <= x2)
{
if (x >= x1)
{
grayImage.putByteSample(x - x1, y, dest[offset]);
}
x += incr;
offset++;
}
break;
}
case(8):
{
Gray8Image grayImage = (Gray8Image)image;
while (x <= x2)
{
if (x >= x1)
{
grayImage.putSample(x - x1, y, buffer[offset]);
}
x += incr;
offset++;
}
break;
}
case(16):
{
Gray16Image grayImage = (Gray16Image)image;
while (x <= x2)
{
if (x >= x1)
{
int sample = (buffer[offset] & 0xff) << 8;
sample |= (buffer[offset + 1] & 0xff);
grayImage.putSample(x, y, sample);
}
x += incr;
offset += 2;
}
break;
}
}
}
private void storeInterlacedAdam7GrayAlpha(int pass, int y, byte[] buffer)
{
int x = ADAM7_FIRST_COLUMN[pass];
final int incr = ADAM7_COLUMN_INCREMENT[pass];
final int x1 = getBoundsX1();
final int x2 = getBoundsX2();
int offset = 0;
switch(precision)
{
case(8):
{
Gray8Image grayImage = (Gray8Image)image;
while (x <= x2)
{
if (x >= x1)
{
grayImage.putSample(x - x1, y, buffer[offset]);
// alpha
}
x += incr;
offset += 2;
}
break;
}
case(16):
{
Gray16Image grayImage = (Gray16Image)image;
while (x <= x2)
{
if (x >= x1)
{
int sample = (buffer[offset] & 0xff) << 8;
sample |= (buffer[offset + 1] & 0xff);
grayImage.putSample(x, y, sample);
// store alpha
}
x += incr;
offset += 4;
}
break;
}
}
}
private void storeInterlacedAdam7Indexed(int pass, int y, byte[] buffer)
{
Paletted8Image palImage = (Paletted8Image)image;
int x = ADAM7_FIRST_COLUMN[pass];
final int incr = ADAM7_COLUMN_INCREMENT[pass];
final int x1 = getBoundsX1();
final int x2 = getBoundsX2();
int offset = 0;
int numColumns = computeColumnsAdam7(pass);
int numPackedBytes = computeBytesPerRow(numColumns);
byte[] dest = new byte[numColumns + 7];
switch(precision)
{
case(1):
{
ArrayConverter.decodePacked1Bit(buffer, 0, dest, 0, numPackedBytes);
while (x <= x2)
{
if (x >= x1)
{
palImage.putByteSample(x - x1, y, dest[offset]);
}
x += incr;
offset++;
}
break;
}
case(2):
{
ArrayConverter.decodePacked2Bit(buffer, 0, dest, 0, numPackedBytes);
while (x <= x2)
{
if (x >= x1)
{
palImage.putByteSample(x - x1, y, dest[offset]);
}
x += incr;
offset++;
}
break;
}
case(4):
{
ArrayConverter.decodePacked4Bit(buffer, 0, dest, 0, numPackedBytes);
while (x <= x2)
{
if (x >= x1)
{
palImage.putByteSample(x - x1, y, dest[offset]);
}
x += incr;
offset++;
}
break;
}
case(8):
{
while (x <= x2)
{
if (x >= x1)
{
palImage.putSample(x - x1, y, buffer[offset]);
}
x += incr;
offset++;
}
break;
}
}
}
private void storeInterlacedAdam7Rgb(int pass, int y, byte[] buffer)
{
int x = ADAM7_FIRST_COLUMN[pass];
final int x1 = getBoundsX1();
final int x2 = getBoundsX2();
final int incr = ADAM7_COLUMN_INCREMENT[pass];
int offset = 0;
if (precision == 8)
{
RGB24Image rgbImage = (RGB24Image)image;
while (x <= x2)
{
if (x >= x1)
{
rgbImage.putSample(RGB24Image.INDEX_RED, x, y, buffer[offset]);
rgbImage.putSample(RGB24Image.INDEX_GREEN, x, y, buffer[offset + 1]);
rgbImage.putSample(RGB24Image.INDEX_BLUE, x, y, buffer[offset + 2]);
}
x += incr;
offset += 3;
}
}
else
if (precision == 16)
{
RGB48Image rgbImage = (RGB48Image)image;
while (x <= x2)
{
if (x >= x1)
{
int red = (buffer[offset] & 0xff) << 8;
red |= buffer[offset + 1] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_RED, x, y, red);
int green = (buffer[offset + 2] & 0xff) << 8;
green |= buffer[offset + 3] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_GREEN, x, y, green);
int blue = (buffer[offset + 4] & 0xff) << 8;
blue |= buffer[offset + 5] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_BLUE, x, y, blue);
}
x += incr;
offset += 6;
}
}
}
private void storeInterlacedAdam7RgbAlpha(int pass, int y, byte[] buffer)
{
int x = ADAM7_FIRST_COLUMN[pass];
final int x1 = getBoundsX1();
final int x2 = getBoundsX2();
final int incr = ADAM7_COLUMN_INCREMENT[pass];
int offset = 0;
if (precision == 8)
{
RGB24Image rgbImage = (RGB24Image)image;
while (x <= x2)
{
if (x >= x1)
{
rgbImage.putSample(RGB24Image.INDEX_RED, x, y, buffer[offset]);
rgbImage.putSample(RGB24Image.INDEX_GREEN, x, y, buffer[offset + 1]);
rgbImage.putSample(RGB24Image.INDEX_BLUE, x, y, buffer[offset + 2]);
// store alpha
}
x += incr;
offset += 4;
}
}
else
if (precision == 16)
{
RGB48Image rgbImage = (RGB48Image)image;
while (x <= x2)
{
if (x >= x1)
{
int red = (buffer[offset] & 0xff) << 8;
red |= buffer[offset + 1] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_RED, x, y, red);
int green = (buffer[offset + 2] & 0xff) << 8;
green |= buffer[offset + 3] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_GREEN, x, y, green);
int blue = (buffer[offset + 4] & 0xff) << 8;
blue |= buffer[offset + 5] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_BLUE, x, y, blue);
// store alpha
}
x += incr;
offset += 8;
}
}
}
private void storeNonInterlaced(int y, byte[] buffer)
{
switch(colorType)
{
case(COLOR_TYPE_GRAY):
{
storeNonInterlacedGray(y, buffer);
break;
}
case(COLOR_TYPE_GRAY_ALPHA):
{
storeNonInterlacedGrayAlpha(y, buffer);
break;
}
case(COLOR_TYPE_INDEXED):
{
storeNonInterlacedIndexed(y, buffer);
break;
}
case(COLOR_TYPE_RGB):
{
storeNonInterlacedRgb(y, buffer);
break;
}
case(COLOR_TYPE_RGB_ALPHA):
{
storeNonInterlacedRgbAlpha(y, buffer);
break;
}
}
}
private void storeNonInterlacedGray(int y, byte[] buffer)
{
switch(precision)
{
case(1):
{
BilevelImage bilevelImage = (BilevelImage)image;
int x1 = getBoundsX1();
bilevelImage.putPackedBytes(0, y, getBoundsWidth(), buffer, x1 / 8, x1 % 8);
break;
}
case(2):
{
Gray8Image grayImage = (Gray8Image)image;
byte[] dest = new byte[width + 3];
ArrayConverter.convertPacked2BitIntensityTo8Bit(buffer, 0, dest, 0, buffer.length);
grayImage.putByteSamples(0, 0, y, getBoundsWidth(), 1, dest, getBoundsX1());
break;
}
case(4):
{
Gray8Image grayImage = (Gray8Image)image;
byte[] dest = new byte[width + 1];
ArrayConverter.convertPacked4BitIntensityTo8Bit(buffer, 0, dest, 0, buffer.length);
grayImage.putByteSamples(0, 0, y, getBoundsWidth(), 1, dest, getBoundsX1());
break;
}
case(8):
{
Gray8Image grayImage = (Gray8Image)image;
int offset = getBoundsX1();
int x = 0;
int k = getBoundsWidth();
while (k > 0)
{
grayImage.putSample(0, x++, y, buffer[offset++]);
k--;
}
break;
}
case(16):
{
Gray16Image grayImage = (Gray16Image)image;
int offset = getBoundsX1();
int x = 0;
int k = getBoundsWidth();
while (k > 0)
{
int sample = (buffer[offset++] & 0xff) << 8;
sample |= (buffer[offset++] & 0xff);
grayImage.putSample(x++, y, sample);
k--;
}
break;
}
}
}
private void storeNonInterlacedGrayAlpha(int y, byte[] buffer)
{
switch(precision)
{
case(8):
{
Gray8Image grayImage = (Gray8Image)image;
int offset = getBoundsX1();
int x = 0;
int k = getBoundsWidth();
while (k > 0)
{
grayImage.putSample(0, x++, y, buffer[offset++]);
offset++; // skip alpha; should be stored in a TransparencyInformation object
k--;
}
break;
}
case(16):
{
Gray16Image grayImage = (Gray16Image)image;
int offset = getBoundsX1();
int x = 0;
int k = getBoundsWidth();
while (k > 0)
{
int sample = (buffer[offset++] & 0xff) << 8;
sample |= (buffer[offset++] & 0xff);
grayImage.putSample(x++, y, sample);
offset += 2; // skip alpha; TODO: store in TransparencyInformation object
k--;
}
break;
}
}
}
private void storeNonInterlacedIndexed(int y, byte[] buffer)
{
Paletted8Image palImage = (Paletted8Image)image;
switch(precision)
{
case(1):
{
byte[] dest = new byte[width + 7];
ArrayConverter.decodePacked1Bit(buffer, 0, dest, 0, buffer.length);
palImage.putByteSamples(0, 0, y, getBoundsWidth(), 1, dest, getBoundsX1());
break;
}
case(2):
{
byte[] dest = new byte[width + 3];
ArrayConverter.decodePacked2Bit(buffer, 0, dest, 0, buffer.length);
palImage.putByteSamples(0, 0, y, getBoundsWidth(), 1, dest, getBoundsX1());
break;
}
case(4):
{
byte[] dest = new byte[width + 1];
ArrayConverter.decodePacked4Bit(buffer, 0, dest, 0, buffer.length);
palImage.putByteSamples(0, 0, y, getBoundsWidth(), 1, dest, getBoundsX1());
break;
}
case(8):
{
int offset = getBoundsX1();
int x = 0;
int k = getBoundsWidth();
while (k > 0)
{
palImage.putSample(0, x++, y, buffer[offset++]);
k--;
}
break;
}
}
}
private void storeNonInterlacedRgb(int y, byte[] buffer)
{
if (precision == 8)
{
RGB24Image rgbImage = (RGB24Image)image;
int offset = getBoundsX1() * 3;
int x = 0;
int k = getBoundsWidth();
while (k > 0)
{
rgbImage.putSample(RGB24Image.INDEX_RED, x, y, buffer[offset++]);
rgbImage.putSample(RGB24Image.INDEX_GREEN, x, y, buffer[offset++]);
rgbImage.putSample(RGB24Image.INDEX_BLUE, x, y, buffer[offset++]);
x++;
k--;
}
}
else
if (precision == 16)
{
RGB48Image rgbImage = (RGB48Image)image;
int offset = getBoundsX1() * 6;
int x = 0;
int k = getBoundsWidth();
while (k > 0)
{
int red = (buffer[offset++] & 0xff) << 8;
red |= buffer[offset++] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_RED, x, y, red);
int green = (buffer[offset++] & 0xff) << 8;
green |= buffer[offset++] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_GREEN, x, y, green);
int blue = (buffer[offset++] & 0xff) << 8;
blue |= buffer[offset++] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_BLUE, x, y, blue);
x++;
k--;
}
}
}
private void storeNonInterlacedRgbAlpha(int y, byte[] buffer)
{
switch(precision)
{
case(8):
{
RGB24Image rgbImage = (RGB24Image)image;
int offset = getBoundsX1() * 3;
int x = 0;
int k = getBoundsWidth();
while (k > 0)
{
rgbImage.putSample(RGB24Image.INDEX_RED, x, y, buffer[offset++]);
rgbImage.putSample(RGB24Image.INDEX_GREEN, x, y, buffer[offset++]);
rgbImage.putSample(RGB24Image.INDEX_BLUE, x, y, buffer[offset++]);
offset++; // skip alpha; TODO: store in TransparencyInformation object
x++;
k--;
}
break;
}
case(16):
{
RGB48Image rgbImage = (RGB48Image)image;
int offset = getBoundsX1() * 8;
int x = 0;
int k = getBoundsWidth();
while (k > 0)
{
int red = (buffer[offset++] & 0xff) << 8;
red |= buffer[offset++] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_RED, x, y, red);
int green = (buffer[offset++] & 0xff) << 8;
green |= buffer[offset++] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_GREEN, x, y, green);
int blue = (buffer[offset++] & 0xff) << 8;
blue |= buffer[offset++] & 0xff;
rgbImage.putSample(RGB24Image.INDEX_BLUE, x, y, blue);
offset += 2; // skip alpha; TODO: store in TransparencyInformation object
x++;
k--;
}
break;
}
}
}
public String suggestFileExtension(PixelImage image)
{
return ".png";
}
}