/**
* decodes the bytes currently captured in the streamBytes and replaces it with an image representation of the bytes
* (this will either be a png or a tiff, depending on the color depth of the image)
* @throws IOException
*/
private void DecodeImageBytes() {
if (streamContentType != null)
throw new ArgumentException(MessageLocalization.GetComposedMessage("Decoding.can't.happen.on.this.type.of.stream.(.1.)", streamContentType.FileExtension));
pngColorType = -1;
PdfArray decode = dictionary.GetAsArray(PdfName.DECODE);
width = dictionary.GetAsNumber(PdfName.WIDTH).IntValue;
height = dictionary.GetAsNumber(PdfName.HEIGHT).IntValue;
bpc = dictionary.GetAsNumber(PdfName.BITSPERCOMPONENT).IntValue;
pngBitDepth = bpc;
PdfObject colorspace = dictionary.GetDirectObject(PdfName.COLORSPACE);
if (colorspace is PdfName && colorSpaceDic != null){
PdfObject csLookup = colorSpaceDic.GetDirectObject((PdfName)colorspace);
if (csLookup != null)
colorspace = csLookup;
}
palette = null;
icc = null;
stride = 0;
FindColorspace(colorspace, true);
MemoryStream ms = new MemoryStream();
if (pngColorType < 0) {
if (bpc != 8)
throw new UnsupportedPdfException(MessageLocalization.GetComposedMessage("the.color.depth.1.is.not.supported", bpc));
if (PdfName.DEVICECMYK.Equals(colorspace)) {
}
else if (colorspace is PdfArray) {
PdfArray ca = (PdfArray)colorspace;
PdfObject tyca = ca.GetDirectObject(0);
if (!PdfName.ICCBASED.Equals(tyca))
throw new UnsupportedPdfException(MessageLocalization.GetComposedMessage("the.color.space.1.is.not.supported", colorspace));
PRStream pr = (PRStream)ca.GetDirectObject(1);
int n = pr.GetAsNumber(PdfName.N).IntValue;
if (n != 4) {
throw new UnsupportedPdfException(MessageLocalization.GetComposedMessage("N.value.1.is.not.supported", n));
}
icc = PdfReader.GetStreamBytes(pr);
}
else
throw new UnsupportedPdfException(MessageLocalization.GetComposedMessage("the.color.space.1.is.not.supported", colorspace));
stride = 4 * width;
TiffWriter wr = new TiffWriter();
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_SAMPLESPERPIXEL, 4));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_BITSPERSAMPLE, new int[]{8,8,8,8}));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_PHOTOMETRIC, TIFFConstants.PHOTOMETRIC_SEPARATED));
wr.AddField(new TiffWriter.FieldLong(TIFFConstants.TIFFTAG_IMAGEWIDTH, width));
wr.AddField(new TiffWriter.FieldLong(TIFFConstants.TIFFTAG_IMAGELENGTH, height));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_COMPRESSION, TIFFConstants.COMPRESSION_LZW));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_PREDICTOR, TIFFConstants.PREDICTOR_HORIZONTAL_DIFFERENCING));
wr.AddField(new TiffWriter.FieldLong(TIFFConstants.TIFFTAG_ROWSPERSTRIP, height));
wr.AddField(new TiffWriter.FieldRational(TIFFConstants.TIFFTAG_XRESOLUTION, new int[]{300,1}));
wr.AddField(new TiffWriter.FieldRational(TIFFConstants.TIFFTAG_YRESOLUTION, new int[]{300,1}));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_RESOLUTIONUNIT, TIFFConstants.RESUNIT_INCH));
wr.AddField(new TiffWriter.FieldAscii(TIFFConstants.TIFFTAG_SOFTWARE, Version.GetInstance().GetVersion));
MemoryStream comp = new MemoryStream();
TiffWriter.CompressLZW(comp, 2, imageBytes, height, 4, stride);
byte[] buf = comp.ToArray();
wr.AddField(new TiffWriter.FieldImage(buf));
wr.AddField(new TiffWriter.FieldLong(TIFFConstants.TIFFTAG_STRIPBYTECOUNTS, buf.Length));
if (icc != null)
wr.AddField(new TiffWriter.FieldUndefined(TIFFConstants.TIFFTAG_ICCPROFILE, icc));
wr.WriteFile(ms);
streamContentType = ImageBytesType.CCITT;
imageBytes = ms.ToArray();
return;
}
else {
PngWriter png = new PngWriter(ms);
if (decode != null){
if (pngBitDepth == 1){
// if the decode array is 1,0, then we need to invert the image
if (decode.GetAsNumber(0).IntValue == 1 && decode.GetAsNumber(1).IntValue == 0){
int len = imageBytes.Length;
for (int t = 0; t < len; ++t) {
imageBytes[t] ^= 0xff;
}
} else {
// if the decode array is 0,1, do nothing. It's possible that the array could be 0,0 or 1,1 - but that would be silly, so we'll just ignore that case
}
} else {
// todo: add decode transformation for other depths
}
}
png.WriteHeader(width, height, pngBitDepth, pngColorType);
if (icc != null)
png.WriteIccProfile(icc);
if (palette != null)
png.WritePalette(palette);
png.WriteData(imageBytes, stride);
png.WriteEnd();
streamContentType = ImageBytesType.PNG;
imageBytes = ms.ToArray();
}
}
public byte[] GetImageAsBytes() {
if (streamBytes == null)
return null;
if (!decoded) {
// if the stream hasn't been decoded, check to see if it is a single stage JPG or JPX encoded stream. If it is,
// then we can just use stream as-is
PdfName filter = dictionary.GetAsName(PdfName.FILTER);
if (filter == null){
PdfArray filterArray = dictionary.GetAsArray(PdfName.FILTER);
if (filterArray.Size == 1){
filter = filterArray.GetAsName(0);
} else {
throw new UnsupportedPdfException("Multi-stage filters not supported here (" + filterArray + ")");
}
}
if (PdfName.DCTDECODE.Equals(filter)) {
fileType = TYPE_JPG;
return streamBytes;
}
else if (PdfName.JPXDECODE.Equals(filter)) {
fileType = TYPE_JP2;
return streamBytes;
}
throw new UnsupportedPdfException("Unsupported stream filter " + filter);
}
pngColorType = -1;
width = dictionary.GetAsNumber(PdfName.WIDTH).IntValue;
height = dictionary.GetAsNumber(PdfName.HEIGHT).IntValue;
bpc = dictionary.GetAsNumber(PdfName.BITSPERCOMPONENT).IntValue;
pngBitDepth = bpc;
PdfObject colorspace = dictionary.GetDirectObject(PdfName.COLORSPACE);
palette = null;
icc = null;
stride = 0;
FindColorspace(colorspace, true);
MemoryStream ms = new MemoryStream();
if (pngColorType < 0) {
if (bpc != 8)
return null;
if (PdfName.DEVICECMYK.Equals(colorspace)) {
}
else if (colorspace is PdfArray) {
PdfArray ca = (PdfArray)colorspace;
PdfObject tyca = ca.GetDirectObject(0);
if (!PdfName.ICCBASED.Equals(tyca))
return null;
PRStream pr = (PRStream)ca.GetDirectObject(1);
int n = pr.GetAsNumber(PdfName.N).IntValue;
if (n != 4) {
return null;
}
icc = PdfReader.GetStreamBytes(pr);
}
else
return null;
stride = 4 * width;
TiffWriter wr = new TiffWriter();
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_SAMPLESPERPIXEL, 4));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_BITSPERSAMPLE, new int[]{8,8,8,8}));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_PHOTOMETRIC, TIFFConstants.PHOTOMETRIC_SEPARATED));
wr.AddField(new TiffWriter.FieldLong(TIFFConstants.TIFFTAG_IMAGEWIDTH, width));
wr.AddField(new TiffWriter.FieldLong(TIFFConstants.TIFFTAG_IMAGELENGTH, height));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_COMPRESSION, TIFFConstants.COMPRESSION_LZW));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_PREDICTOR, TIFFConstants.PREDICTOR_HORIZONTAL_DIFFERENCING));
wr.AddField(new TiffWriter.FieldLong(TIFFConstants.TIFFTAG_ROWSPERSTRIP, height));
wr.AddField(new TiffWriter.FieldRational(TIFFConstants.TIFFTAG_XRESOLUTION, new int[]{300,1}));
wr.AddField(new TiffWriter.FieldRational(TIFFConstants.TIFFTAG_YRESOLUTION, new int[]{300,1}));
wr.AddField(new TiffWriter.FieldShort(TIFFConstants.TIFFTAG_RESOLUTIONUNIT, TIFFConstants.RESUNIT_INCH));
wr.AddField(new TiffWriter.FieldAscii(TIFFConstants.TIFFTAG_SOFTWARE, Document.Version));
MemoryStream comp = new MemoryStream();
TiffWriter.CompressLZW(comp, 2, streamBytes, height, 4, stride);
byte[] buf = comp.ToArray();
wr.AddField(new TiffWriter.FieldImage(buf));
wr.AddField(new TiffWriter.FieldLong(TIFFConstants.TIFFTAG_STRIPBYTECOUNTS, buf.Length));
if (icc != null)
wr.AddField(new TiffWriter.FieldUndefined(TIFFConstants.TIFFTAG_ICCPROFILE, icc));
wr.WriteFile(ms);
fileType = TYPE_TIF;
return ms.ToArray();
}
PngWriter png = new PngWriter(ms);
png.WriteHeader(width, height, pngBitDepth, pngColorType);
if (icc != null)
png.WriteIccProfile(icc);
if (palette != null)
png.WritePalette(palette);
png.WriteData(streamBytes, stride);
png.WriteEnd();
fileType = TYPE_PNG;
return ms.ToArray();
}
