Public Member Functions | |
| DcmRLEEncoder (int doPad) | |
| default constructor | |
| ~DcmRLEEncoder () | |
| destructor | |
| void | add (unsigned char ch) |
| this method adds one byte to the byte stream to be compressed with the RLE compressor. | |
| void | add (const unsigned char *buf, size_t bufcount) |
| this method adds a block of bytes to the byte stream to be compressed with the RLE compressor. | |
| void | flush () |
| this method finalizes the compressed RLE stream, i.e. | |
| size_t | size () const |
| returns the size of compressed RLE stream in bytes. | |
| OFBool | fail () const |
| returns true if the RLE compressor has run out of memory. | |
| void | write (void *target) const |
| copies the compressed RLE byte stream into a target array of at least size() bytes. | |
| void | write (DcmEncoderOutputStream &os) const |
| copies the compressed RLE byte stream into an output stream | |
Private Member Functions | |
| DcmRLEEncoder (const DcmRLEEncoder &) | |
| private undefined copy constructor | |
| DcmRLEEncoder & | operator= (const DcmRLEEncoder &) |
| private undefined copy assignment operator | |
| void | move (size_t numberOfBytes) |
| this method moves the given number of bytes from buff_ to currentBlock_ and "flushes" currentBlock_ to blockList_ if necessary. | |
Private Attributes | |
| int | fail_ |
| this flag indicates a failure of the RLE codec. | |
| int | pad_ |
| this flag indicates whether the RLE codec must pad encoded data to an even number of bytes (as required by DICOM). | |
| unsigned char * | currentBlock_ |
| this member points to a block of size DcmRLEEncoder_BLOCKSIZE (unless fail_ is true). | |
| size_t | offset_ |
| contains the number of bytes already written the the memory block pointed to by currentBlock_. | |
| OFList< unsigned char * > | blockList_ |
| this member contains a list of memory blocks of size DcmRLEEncoder_BLOCKSIZE which already have been filled with encoded RLE data. | |
| unsigned char * | RLE_buff_ |
| this member points to a buffer of 132 bytes that is used by the RLE encoding algorithm. | |
| int | RLE_prev_ |
| value of the last byte fed to the RLE compressor. | |
| int | RLE_pcount_ |
| repeat counter, for RLE compressor may temporarily become negative, guaranteed to be >= 0 between method calls. | |
| unsigned int | RLE_bindex_ |
| index of next unused byte in RLE_buff_. | |
The class is loosely based on an implementation by Phil Norman.
Definition at line 64 of file dcrleenc.h.
| DcmRLEEncoder::DcmRLEEncoder | ( | int | doPad | ) | [inline] |
default constructor
| doPad | if true, RLE codec will pad output data to even number of bytes |
Definition at line 71 of file dcrleenc.h.
References currentBlock_, fail_, and RLE_buff_.
| void DcmRLEEncoder::add | ( | unsigned char | ch | ) | [inline] |
this method adds one byte to the byte stream to be compressed with the RLE compressor.
| ch | byte to be added |
Definition at line 104 of file dcrleenc.h.
References fail_, move(), RLE_bindex_, RLE_buff_, RLE_pcount_, and RLE_prev_.
Referenced by add().
| void DcmRLEEncoder::add | ( | const unsigned char * | buf, | |
| size_t | bufcount | |||
| ) | [inline] |
this method adds a block of bytes to the byte stream to be compressed with the RLE compressor.
| buf | buffer to be added | |
| bufcount | number of bytes in buffer |
Definition at line 181 of file dcrleenc.h.
References add().
| void DcmRLEEncoder::flush | ( | ) | [inline] |
this method finalizes the compressed RLE stream, i.e.
flushes all pending literal or repeat runs. This method can be called at any time; however, it must be called before size() or write() can be used. Intermediate calls should be avoided since they possibly decrease the compression ratio.
Definition at line 195 of file dcrleenc.h.
References fail_, move(), RLE_bindex_, RLE_buff_, RLE_pcount_, and RLE_prev_.
| size_t DcmRLEEncoder::size | ( | ) | const [inline] |
returns the size of compressed RLE stream in bytes.
The size is guaranteed to be an even number of bytes (padded with a trailing zero byte as required by DICOM if necessary). This method may only be called after flush() has been executed to finalize the compressed stream.
Definition at line 256 of file dcrleenc.h.
References blockList_, offset_, pad_, and OFList< T >::size().
| OFBool DcmRLEEncoder::fail | ( | ) | const [inline] |
returns true if the RLE compressor has run out of memory.
In this case, no output has been created.
Definition at line 266 of file dcrleenc.h.
References fail_.
| void DcmRLEEncoder::write | ( | void * | target | ) | const [inline] |
copies the compressed RLE byte stream into a target array of at least size() bytes.
| target | pointer to array of at least size() bytes, must not be NULL. |
Definition at line 275 of file dcrleenc.h.
References OFList< T >::begin(), blockList_, currentBlock_, OFList< T >::end(), fail_, offset_, pad_, and OFList< T >::size().
| void DcmRLEEncoder::write | ( | DcmEncoderOutputStream & | os | ) | const [inline] |
copies the compressed RLE byte stream into an output stream
| os | output stream |
Definition at line 308 of file dcrleenc.h.
References OFList< T >::begin(), blockList_, currentBlock_, OFList< T >::end(), fail_, offset_, pad_, OFList< T >::size(), and DcmEncoderOutputStream::write().
| void DcmRLEEncoder::move | ( | size_t | numberOfBytes | ) | [inline, private] |
this method moves the given number of bytes from buff_ to currentBlock_ and "flushes" currentBlock_ to blockList_ if necessary.
| numberOfBytes | number of bytes to copy |
Definition at line 346 of file dcrleenc.h.
References blockList_, currentBlock_, fail_, offset_, OFList< T >::push_back(), and RLE_buff_.
int DcmRLEEncoder::fail_ [private] |
this flag indicates a failure of the RLE codec.
Once a failure is flagged, the codec will consume all input and not produce any more output. A failure status can only be caused by an out-of-memory condition.
Definition at line 373 of file dcrleenc.h.
Referenced by add(), DcmRLEEncoder(), fail(), flush(), move(), and write().
int DcmRLEEncoder::pad_ [private] |
this flag indicates whether the RLE codec must pad encoded data to an even number of bytes (as required by DICOM).
True if padding is required, false otherwise
Definition at line 379 of file dcrleenc.h.
unsigned char* DcmRLEEncoder::currentBlock_ [private] |
this member points to a block of size DcmRLEEncoder_BLOCKSIZE (unless fail_ is true).
This is the current block of data to which the RLE stream is written
Definition at line 385 of file dcrleenc.h.
Referenced by DcmRLEEncoder(), move(), write(), and ~DcmRLEEncoder().
size_t DcmRLEEncoder::offset_ [private] |
contains the number of bytes already written the the memory block pointed to by currentBlock_.
Value is always less than DcmRLEEncoder_BLOCKSIZE.
Definition at line 391 of file dcrleenc.h.
OFList<unsigned char *> DcmRLEEncoder::blockList_ [private] |
this member contains a list of memory blocks of size DcmRLEEncoder_BLOCKSIZE which already have been filled with encoded RLE data.
The current block (pointed to by currentBlock_) is not contained in this list.
Definition at line 397 of file dcrleenc.h.
Referenced by move(), size(), write(), and ~DcmRLEEncoder().
int DcmRLEEncoder::RLE_prev_ [private] |
value of the last byte fed to the RLE compressor.
This byte is not yet stored in the RLE_buff_ buffer. Type is int because this allows an "impossible" -1 as default value
Definition at line 408 of file dcrleenc.h.