L_DicomSetImage

#include "Ltdic.h"

L_LTDIC_API L_UINT16 L_DicomSetImage(hDS, pElement, pBitmap, nCompression, nPhotometric, nBitsPerPixel, nQFactor, uFlags, pfnCallback, pUserData)

Replaces the image(s) in a Pixel Data element.

Parameters

HDICOMDS hDS

A DICOM handle.

pDICOMELEMENT pElement

Pointer to a DICOMELEMENT structure within the Data Set.

pBITMAPHANDLE pBitmap

Pointer to the bitmap handle that references the image to set.

L_INT32 nCompression

Value that indicates the type of compression to use, which are affect the way the image is compressed when call the function. Possible values are:

L_INT32 nPhotometric

Photometric constant. Possible values are:

L_INT32 nBitsPerPixel

Resulting bitmap pixel depth. Possible values are:

L_INT32 nQFactor

The quality factor (Q factor) is a number that determines the degree of loss in the compression process. You can set a value from 2 to 255, where 2 is the highest quality and 255 is the most compression.

L_UINT uFlags

Flags which control the behaviour of this function. Possible values are:

FILESAVECALLBACK pfnCallback

Optional callback function for additional processing. If you do not provide a callback function, use NULL as the value of this parameter. If you do provide a callback function, use the function pointer as the value of this parameter.

The callback function must adhere to the function prototype described in FILESAVECALLBACK Function.

L_VOID *pUserData

Void pointer that you can use to pass one or more additional parameters that the callback function needs.

To use this feature, assign a value to a variable or create a structure that contains as many fields as you need. Then, in this parameter, pass the address of the variable or structure, casting it to L_VOID. The callback function, which receives the address in its own pUserData parameter, can cast it to a pointer of the appropriate data type to access your variable or structure. If the additional parameters are not needed, you can pass NULL in this parameter.

Returns

Comments

This function replaces all the images in the Pixel Data Element with the image referenced by pBitmap.

Most DICOM files will only have one Data Element of type TAG_PIXEL_DATA. Therefore, in most instances you can set pElement to NULL, since the function will automatically replace the images of the only Pixel Data Element in the file. If pElement is not NULL, it must point to the Pixel Data Element itself.

If the DICOM file is CLASS_BASIC_DIRECTORY, the file may contain more than one Pixel Data Element. In this case you must specify in pElement the Pixel Data Element in which the images will be replaced.

If you wish to replace only one image within the Pixel Data Element, you must use L_DicomDeleteImage and L_DicomInsertImage.

For a table of possible Compression, Photometric, BitsPerPixel, and Quality Factor combinations, refer to Compression Table.

For more options when using the JPEG 2000 compression, refer to L_DicomSetJ2KOptions.

This function will either insert, delete or update one or more of the following elements:

If the Shared Functional Groups Sequence element or the Per-frame Functional Groups Sequence element is added, an item child element may be added that contains either the (0028,9132) Frame VOI LUT Sequence element or the (0028,9145) Pixel Value Transformation Sequence element.

(0028,9132) Frame VOI LUT Sequence Child Elements

(0028,9145) Pixel Value Transformation Sequence child elements

This function is indifferent to the pixel data restrictions imposed by the various DICOM IOD classes, for example this function will allow the user to insert a colored image into a "Digital X-Ray Image Storage" dataset.

This function will always insert a "Number of Frames" (0028, 0008) element and set its value.

The Multi-frame Functional Groups module may have a Shared Functional Groups Sequence item, and/or a Per-frame Functional Groups Sequence item. Either of these items may have a Pixel Value Transformation Sequence (0028,9145) item, or a Frame VOI LUT Sequence (0028,9132) item.

When calling the methods L_DicomSetImage or L_DicomSetImageList, the five DICOM_SETIMAGE_MFG replace existing information in the Pixel Value Transformation Sequence or the Frame VOI LUT Sequence.

and  any existing Shared Functional Groups Sequence items, and Per-frame Functional Groups Sequence items will be removed.

• DICOM_SETIMAGE_MFG_VOI_LUT_PER_FRAME
• DICOM_SETIMAGE_MFG_VOI_LUT_SHARED
• DICOM_SETIMAGE_MFG_MODALITY_LUT_PER_FRAME
• DICOM_SETIMAGE_MFG_MODALITY_LUT_SHARED
• DICOM_SETIMAGE_MFG_VOI_LUT_PER_FRAME
• DICOM_SETIMAGE_MFG_VOI_LUT_SHARED
• DICOM_SETIMAGE_MFG_MODALITY_LUT_PER_FRAME
• DICOM_SETIMAGE_MFG_MODALITY_LUT_SHARED

Any new sequences are placed in the sequence indicated by the flag (Per-frame Functional Groups Sequence or Shared Functional Groups Sequence).

For a detailed discussion on Multi-frame Functional Groups and how the DICOM_SET_IMAGE_MFG flags are used, see the topic Multi-frame Functional Groups.

Notes:

• DICOM_SETIMAGE_MFG_VOI_LUT_PER_FRAME cannot be combined with DICOM_SETIMAGE_MFG_VOI_LUT_SHARED.

• DICOM_SETIMAGE_MFG_MODALITY_LUT_PER_FRAME cannot be combined with DICOM_SETIMAGE_MFG_MODALITY_LUT_SHARED.

• Only valid values are for nPhotometric are:

  • IMAGE_PHOTOMETRIC_MONOCHROME2 (gray)
  • IMAGE_PHOTOMETRIC_PALETTE_COLOR (palletized)
  • IMAGE_PHOTOMETRIC_RGB (Color)

  All other values are ignored.

The nPhotometric  parameter is used as an indicator as how the data image data will be saved: gray, color, or palletized. The nPhotometric parameter is NOT necessarily going to be the final value of the Photometric Interpretation that is stored in the resulting DICOM dataset.  The resulting Photometric Interpretation in the DICOM dataset is set automatically, based on the compression type, flags, and QFactor.  The table below gives examples of the resulting DICOM dataset Photometric Interpretation, based on various input parameters:

Notes:

• There is no high level function to embed MPEG2 into a DICOM dataset. The Multimedia toolkit (DICOM writer) can create DICOM files with MPEG2 compression.

• This function cannot be used to encode DICOM transfer syntaxes (e.g. video compression support) that are not part of the main medical SDK and it is supported only via the LEADTOOLS Medical Module.

Required DLLs and Libraries

• LTDIC
• For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application

Platforms

Win32, x64, Linux.

L_INT DicomSetImageExample(pBITMAPHANDLE pBitmap) 
{ 
   HDICOMDS      hDS; 
   pDICOMELEMENT pElement; 
   L_UINT16 nRet; 
 
   hDS = L_DicomCreateDS(NULL); 
 
   nRet = L_DicomLoadDS(hDS, MAKE_IMAGE_PATH(TEXT("Image1.dcm")), 0); 
   if (nRet != DICOM_SUCCESS) 
   { 
      L_DicomFreeDS(hDS); 
      return nRet; 
   } 
 
   pElement = L_DicomFindFirstElement(hDS, NULL, TAG_PIXEL_DATA, FALSE); 
   if (pElement != NULL) 
   { 
      nRet = L_DicomSetImage(hDS, pElement, pBitmap, IMAGE_COMPRESSION_NONE, 
                      IMAGE_PHOTOMETRIC_MONOCHROME1, 0, 0, DICOM_SETIMAGE_AUTO_SET_VOI_LUT, NULL, NULL); 
      if (nRet != DICOM_SUCCESS) 
      { 
         L_DicomFreeDS(hDS); 
         return nRet; 
      } 
   } 
 
   L_DicomFreeDS(hDS); 
   return DICOM_SUCCESS; 
}