/**
* Compresses the stream.
* @param compressionLevel the compression level (0 = best speed, 9 = best compression, -1 is default)
* @since 2.1.3
*/
public void FlateCompress(int compressionLevel)
{
if (!Document.Compress)
return;
// check if the flateCompress-method has allready been
if (compressed) {
return;
}
this.compressionLevel = compressionLevel;
if (inputStream != null) {
compressed = true;
return;
}
// check if a filter allready exists
PdfObject filter = PdfReader.GetPdfObject(Get(PdfName.FILTER));
if (filter != null) {
if (filter.IsName()) {
if (PdfName.FLATEDECODE.Equals(filter))
return;
}
else if (filter.IsArray()) {
if (((PdfArray) filter).Contains(PdfName.FLATEDECODE))
return;
}
else {
throw new PdfException("Stream could not be compressed: filter is not a name or array.");
}
}
// compress
MemoryStream stream = new MemoryStream();
var zip = new ZOutputStream(stream, compressionLevel);
if (streamBytes != null)
streamBytes.WriteTo(zip);
else
zip.Write(bytes, 0, bytes.Length);
//zip.Close();
zip.Finish();
// update the object
streamBytes = stream;
bytes = null;
Put(PdfName.LENGTH, new PdfNumber(streamBytes.Length));
if (filter == null) {
Put(PdfName.FILTER, PdfName.FLATEDECODE);
}
else {
PdfArray filters = new PdfArray(filter);
filters.Add(PdfName.FLATEDECODE);
Put(PdfName.FILTER, filters);
}
compressed = true;
}
private static void EncryptWithCompressionInternal(DocumentHeaders outputDocumentHeaders, Stream inputStream, CryptoStream encryptingStream, ProgressContext progress)
{
using (ZOutputStream deflatingStream = new ZOutputStream(encryptingStream, -1))
{
deflatingStream.FlushMode = JZlib.Z_SYNC_FLUSH;
CopyToWithCount(inputStream, deflatingStream, progress);
deflatingStream.FlushMode = JZlib.Z_FINISH;
deflatingStream.Finish();
outputDocumentHeaders.UncompressedLength = deflatingStream.TotalIn;
outputDocumentHeaders.PlaintextLength = deflatingStream.TotalOut;
}
}