djcodecd.h

转化为DIB位图再显示出来的dicom文件C++代码

/*
 *
 *  Copyright (C) 1997-2005, OFFIS
 *
 *  This software and supporting documentation were developed by
 *
 *    Kuratorium OFFIS e.V.
 *    Healthcare Information and Communication Systems
 *    Escherweg 2
 *    D-26121 Oldenburg, Germany
 *
 *  THIS SOFTWARE IS MADE AVAILABLE,  AS IS,  AND OFFIS MAKES NO  WARRANTY
 *  REGARDING  THE  SOFTWARE,  ITS  PERFORMANCE,  ITS  MERCHANTABILITY  OR
 *  FITNESS FOR ANY PARTICULAR USE, FREEDOM FROM ANY COMPUTER DISEASES  OR
 *  ITS CONFORMITY TO ANY SPECIFICATION. THE ENTIRE RISK AS TO QUALITY AND
 *  PERFORMANCE OF THE SOFTWARE IS WITH THE USER.
 *
 *  Module:  dcmjpeg
 *
 *  Author:  Marco Eichelberg, Norbert Olges
 *
 *  Purpose: abstract codec class for JPEG decoders.
 *
 *  Last Update:      $Author: meichel $
 *  Update Date:      $Date: 2005/12/08 16:59:11 $
 *  Source File:      $Source: /share/dicom/cvs-depot/dcmtk/dcmjpeg/include/dcmtk/dcmjpeg/djcodecd.h,v $
 *  CVS/RCS Revision: $Revision: 1.5 $
 *  Status:           $State: Exp $
 *
 *  CVS/RCS Log at end of file
 *
 */

#ifndef DJCODECD_H
#define DJCODECD_H

#include "dcmtk/config/osconfig.h"
#include "dcmtk/ofstd/oftypes.h"
#include "dcmtk/dcmdata/dccodec.h"    /* for class DcmCodec */
#include "dcmtk/dcmjpeg/djutils.h"    /* for enums */
#include "dcmtk/ofstd/ofstring.h"   /* for class OFString */


class DataInterface;
class DJEncoder;
class DcmDataset;
class DcmItem;
class DJCodecParameter;
class DJDecoder;

/** abstract codec class for JPEG decoders.
 *  This abstract class contains most of the application logic
 *  needed for a dcmdata codec object that implements a JPEG decoder 
 *  using the DJDecoder interface to the underlying JPEG implementation.
 *  This class only supports decompression, it neither implements
 *  encoding nor transcoding.
 */
class DJCodecDecoder : public DcmCodec
{
public:  
 
  /// default constructor
  DJCodecDecoder();

  /// destructor
  virtual ~DJCodecDecoder();

  /** decompresses the given pixel sequence and
   *  stores the result in the given uncompressedPixelData element.
   *  @param fromRepParam current representation parameter of compressed data, may be NULL
   *  @param pixSeq compressed pixel sequence
   *  @param uncompressedPixelData uncompressed pixel data stored in this element
   *  @param cp codec parameters for this codec
   *  @param objStack stack pointing to the location of the pixel data
   *    element in the current dataset.
   *  @return EC_Normal if successful, an error code otherwise.
   */
  virtual OFCondition decode(
    const DcmRepresentationParameter * fromRepParam,
    DcmPixelSequence * pixSeq,
    DcmPolymorphOBOW& uncompressedPixelData,
    const DcmCodecParameter * cp,
    const DcmStack& objStack) const;

  /** compresses the given uncompressed DICOM image and stores
   *  the result in the given pixSeq element.
   *  @param pixelData pointer to the uncompressed image data in OW format
   *    and local byte order
   *  @param length of the pixel data field in bytes
   *  @param toRepParam representation parameter describing the desired
   *    compressed representation (e.g. JPEG quality)
   *  @param pixSeq compressed pixel sequence (pointer to new DcmPixelSequence object
   *    allocated on heap) returned in this parameter upon success.   
   *  @param cp codec parameters for this codec
   *  @param objStack stack pointing to the location of the pixel data
   *    element in the current dataset.
   *  @return EC_Normal if successful, an error code otherwise.
   */
  virtual OFCondition encode(
    const Uint16 * pixelData,
    const Uint32 length,
    const DcmRepresentationParameter * toRepParam,
    DcmPixelSequence * & pixSeq,
    const DcmCodecParameter *cp,
    DcmStack & objStack) const;

  /** transcodes (re-compresses) the given compressed DICOM image and stores
   *  the result in the given toPixSeq element.
   *  @param fromRepType current transfer syntax of the compressed image
   *  @param fromRepParam current representation parameter of compressed data, may be NULL
   *  @param fromPixSeq compressed pixel sequence
   *  @param toRepParam representation parameter describing the desired
   *    new compressed representation (e.g. JPEG quality)
   *  @param toPixSeq compressed pixel sequence (pointer to new DcmPixelSequence object
   *    allocated on heap) returned in this parameter upon success.   
   *  @param cp codec parameters for this codec
   *  @param objStack stack pointing to the location of the pixel data
   *    element in the current dataset.
   *  @return EC_Normal if successful, an error code otherwise.
   */
  virtual OFCondition encode(
    const E_TransferSyntax fromRepType,
    const DcmRepresentationParameter * fromRepParam,
    DcmPixelSequence * fromPixSeq,
    const DcmRepresentationParameter * toRepParam,
    DcmPixelSequence * & toPixSeq,
    const DcmCodecParameter * cp,
    DcmStack & objStack) const;

  /** checks if this codec is able to convert from the
   *  given current transfer syntax to the given new
   *  transfer syntax
   *  @param oldRepType current transfer syntax
   *  @param newRepType desired new transfer syntax
   *  @return true if transformation is supported by this codec, false otherwise.
   */
  virtual OFBool canChangeCoding(
    const E_TransferSyntax oldRepType,
    const E_TransferSyntax newRepType) const;

  /** returns the transfer syntax that this particular codec
   *  is able to decode.
   *  @return supported transfer syntax
   */
  virtual E_TransferSyntax supportedTransferSyntax() const = 0;

private: 

  /** creates an instance of the compression library to be used for decoding.
   *  @param toRepParam representation parameter passed to decode()
   *  @param cp codec parameter passed to decode()
   *  @param bitsPerSample bits per sample for the image data
   *  @param isYBR flag indicating whether DICOM photometric interpretation is YCbCr
   *  @return pointer to newly allocated decoder object
   */
  virtual DJDecoder *createDecoderInstance(
    const DcmRepresentationParameter * toRepParam,
    const DJCodecParameter *cp,
    Uint8 bitsPerSample,
    OFBool isYBR) const = 0;

  // static private helper methods

  /** scans the given block of JPEG data for a Start of Frame marker
   *  and returns the number of bits per pixel stored in the
   *  Start of Frame block.
   *  @param data pointer to array, must not be NULL
   *  @param fragmentLength size of array
   *  @return bit depth of JPEG data, 0 if no SOF marker found or parse error
   */
  static Uint8 scanJpegDataForBitDepth(
    const Uint8 *data,
    const Uint32 fragmentLength);

  /** reads two bytes from the given array
   *  of little endian 16-bit values and returns
   *  the value as Uint16 in local byte order.
   *  @param data pointer to array, must not be NULL, must at least 2 bytes large
   *  @return Uint16 read from array
   */
  static Uint16 readUint16(const Uint8 *data);

  /** converts an RGB or YBR frame with 8 bits/sample from
   *  color-by-pixel to color-by-plane planar configuration.
   *  @param imageFrame pointer to image frame, must contain
   *    at least 3*columns*rows bytes of pixel data.
   *  @param columns columns
   *  @param rows rows
   *  @return EC_Normal if successful, an error code otherwise
   */
  static OFCondition createPlanarConfigurationByte(
    Uint8 *imageFrame,
    Uint16 columns,
    Uint16 rows);

  /** converts an RGB or YBR frame with 16 bits/sample from
   *  color-by-pixel to color-by-plane planar configuration.
   *  @param imageFrame pointer to image frame, must contain
   *    at least 3*columns*rows words of pixel data.
   *  @param columns columns
   *  @param rows rows
   *  @return EC_Normal if successful, an error code otherwise
   */
  static OFCondition createPlanarConfigurationWord(
    Uint16 *imageFrame,
    Uint16 columns,
    Uint16 rows);

  /** examines if a given image requires color-by-plane planar configuration
   *  depending on SOP Class UID (DICOM IOD) and photometric interpretation.
   *  All SOP classes defined in the 2003 edition of the DICOM standard or earlier
   *  are handled correctly.
   *  @param sopClassUID SOP Class UID
   *  @param photometricInterpretation decompressed photometric interpretation
   *  @return true if color-by-plane is required, false otherwise.
   */
  static OFBool requiresPlanarConfiguration(
    const char *sopClassUID,
    EP_Interpretation photometricInterpretation);

};

#endif

/*
 * CVS/RCS Log
 * $Log: djcodecd.h,v $
 * Revision 1.5  2005/12/08 16:59:11  meichel
 * Changed include path schema for all DCMTK header files
 *
 * Revision 1.4  2004/08/24 14:57:08  meichel
 * Updated compression helper methods. Image type is not set to SECONDARY
 *   any more, support for the purpose of reference code sequence added.
 *
 * Revision 1.3  2003/07/04 13:26:22  meichel
 * Replaced forward declarations for OFString with explicit includes,
 *   needed when compiling with HAVE_STD_STRING
 *
 * Revision 1.2  2002/05/24 14:58:03  meichel
 * Moved helper methods that are useful for different compression techniques
 *   from module dcmjpeg to module dcmdata
 *
 * Revision 1.1  2001/11/13 15:56:16  meichel
 * Initial release of module dcmjpeg
 *
 *
 */