-/**
- * \brief Try to deal with RLE 16 Bits.
- * We assume the RLE has already been parsed and loaded in
- * Raw (through \ref ReadAndDecompressJPEGFile ).
- * We here need to make 16 Bits Pixels from Low Byte and
- * High Byte 'Planes'...(for what it may mean)
- * @return Boolean
- */
-bool PixelReadConvert::DecompressRLE16BitsFromRLE8Bits( int NumberOfFrames )
-{
- size_t pixelNumber = XSize * YSize;
- size_t rawSize = XSize * YSize * NumberOfFrames;
-
- // We assumed Raw contains the decoded RLE pixels but as
- // 8 bits per pixel. In order to convert those pixels to 16 bits
- // per pixel we cannot work in place within Raw and hence
- // we copy it in a safe place, say copyRaw.
-
- uint8_t* copyRaw = new uint8_t[ rawSize * 2 ];
- memmove( copyRaw, Raw, rawSize * 2 );
-
- uint8_t* x = Raw;
- uint8_t* a = copyRaw;
- uint8_t* b = a + pixelNumber;
-
- for ( int i = 0; i < NumberOfFrames; i++ )
- {
- for ( unsigned int j = 0; j < pixelNumber; j++ )
- {
- *(x++) = *(b++);
- *(x++) = *(a++);
- }
- }
-
- delete[] copyRaw;
-
- /// \todo check that operator new []didn't fail, and sometimes return false
- return true;
-}
-
-/**
- * \brief Implementation of the RLE decoding algorithm for decompressing
- * a RLE fragment. [refer to PS 3.5-2003, section G.3.2 p 86]
- * @param subRaw Sub region of \ref Raw where the decoded fragment
- * should be placed.
- * @param fragmentSize The length of the binary fragment as found on the disk.
- * @param RawSegmentSize The expected length of the fragment ONCE
- * Raw.
- * @param fp File Pointer: on entry the position should be the one of
- * the fragment to be decoded.
- */
-bool PixelReadConvert::ReadAndDecompressRLEFragment( uint8_t *subRaw,
- long fragmentSize,
- long RawSegmentSize,
- std::ifstream *fp )
-{
- int8_t count;
- long numberOfOutputBytes = 0;
- long numberOfReadBytes = 0;
-
- while( numberOfOutputBytes < RawSegmentSize )
- {
- fp->read( (char*)&count, 1 );
- numberOfReadBytes += 1;
- if ( count >= 0 )
- // Note: count <= 127 comparison is always true due to limited range
- // of data type int8_t [since the maximum of an exact width
- // signed integer of width N is 2^(N-1) - 1, which for int8_t
- // is 127].
- {
- fp->read( (char*)subRaw, count + 1);
- numberOfReadBytes += count + 1;
- subRaw += count + 1;
- numberOfOutputBytes += count + 1;
- }
- else
- {
- if ( ( count <= -1 ) && ( count >= -127 ) )
- {
- int8_t newByte;
- fp->read( (char*)&newByte, 1);
- numberOfReadBytes += 1;
- for( int i = 0; i < -count + 1; i++ )
- {
- subRaw[i] = newByte;
- }
- subRaw += -count + 1;
- numberOfOutputBytes += -count + 1;
- }
- }
- // if count = 128 output nothing
-
- if ( numberOfReadBytes > fragmentSize )
- {
- gdcmVerboseMacro( "Read more bytes than the segment size.");
- return false;
- }
- }
- return true;
-}
-
-/**
- * \brief Reads from disk the Pixel Data of 'Run Length Encoded'
- * Dicom encapsulated file and decompress it.
- * @param fp already open File Pointer
- * at which the pixel data should be copied
- * @return Boolean
- */
-bool PixelReadConvert::ReadAndDecompressRLEFile( std::ifstream *fp )
-{
- uint8_t *subRaw = Raw;
- long RawSegmentSize = XSize * YSize;
-
- // Loop on the frame[s]
- for( RLEFramesInfo::RLEFrameList::iterator
- it = RLEInfo->Frames.begin();
- it != RLEInfo->Frames.end();
- ++it )
- {
- // Loop on the fragments
- for( unsigned int k = 1; k <= (*it)->NumberFragments; k++ )
- {
- fp->seekg( (*it)->Offset[k] , std::ios::beg );
- (void)ReadAndDecompressRLEFragment( subRaw,
- (*it)->Length[k],
- RawSegmentSize,
- fp );
- subRaw += RawSegmentSize;
- }
- }
-
- if ( BitsAllocated == 16 )
- {
- // Try to deal with RLE 16 Bits
- (void)DecompressRLE16BitsFromRLE8Bits( ZSize );
- }
-
- return true;
-}