#include "Ltdic.h"
L_LTDIC_API L_UINT16 L_DicomGetImageList(hDS, pElement, hList, nIndex, nCount, nBitsPerPixel, uFlags)
Loads the image list with frames from a Pixel Data element.
A DICOM handle.
Pointer to a DICOMELEMENT structure within the Data Set.
Handle to the list of images.
Position of the first frame to get. Use zero-based indexing. For example, if there are 10 images in a list, the index of the last one is 9. To get the last image in the Pixel Data element, use ELEMENT_INDEX_MAX.
Number of frames to load into the image list.
Resulting image pixel depth. Possible values are:
Value | Meaning |
---|---|
0 | Keep the original file's pixel depth (Do not convert). |
1 to 8 | The specified bits per pixel in the resulting image. |
12 | 12 bits per pixel in the resulting image. |
16 | 16 bits per pixel in the resulting image. |
24 | 24 bits per pixel in the resulting image. |
32 | 32 bits per pixel in the resulting image. |
Flags which control the behavior of this function. Possible values are:
Value | Meaning |
---|---|
DICOM_GETIMAGE_AUTO_LOAD_OVERLAYS | [0x0001] If set, the function will automatically extract the overlays included in the dataset and add them to the loaded image. |
DICOM_GETIMAGE_AUTO_APPLY_MODALITY_LUT | [0x0002] If set, the function will automatically apply the "Modality LUT" when loading the image. |
DICOM_GETIMAGE_AUTO_APPLY_VOI_LUT | [0x0004] If set, the function will automatically apply the "VOI LUT" when loading the image. |
DICOM_GETIMAGE_ALLOW_RANGE_EXPANSION | [0x0008] (Deprecated, do not use) If set, the function will adjust the high bit and/or low bit (if possible) inside the image handle in order to hold the range of pixel values after applying the modality LUT. |
DICOM_GETIMAGE_AUTO_SCALE_MODALITY_LUT | [0x0010] If set, the function will scale the resulting pixel data to fit within the range of 0 to 2^BitsPerPixel-1 if any of the values would exceed that range. |
DICOM_GETIMAGE_AUTO_SCALE_VOI_LUT | [0x0020] Only used in conjunction with DICOM_GETIMAGE_AUTO_SCALE_MODALITY_LUT. If set, the function will rescale the VOI LUT to match the rescale that was performed by DICOM_GETIMAGE_AUTO_SCALE_MODALITY_LUT. |
DICOM_GETIMAGE_AUTODETECT_INVALID_RLE_COMPRESSION | [0x0040] For RLE compressed, automatically detects if the MSB and LSB segments are written in the incorrect order. |
DICOM_GETIMAGE_RLE_SWAP_SEGMENTS | [0x0080] Swaps the MSB and LSB segments when loading RLE compressed data. This flag can be used to load RLE compressed data that is stored incorrectly in this manner. Use this flag only in instances where it is known that the RLE compressed data is stored incorrectly. To automatically detect/correct incorrectly stored RLE compressed data, pass the DICOM_GETIMAGE_AUTODETECT_INVALID_RLE_COMPRESSION flag instead. |
DICOM_GETIMAGE_VOI_LUT_PAINT_ONLY | [0x0200] Automatically applies the "VOI LUT" when loading the image, but only for display purposes |
DICOM_GETIMAGE_USE_DISK | [0x0400] Allocates the memory for loading the image using hard disk space (if possible). |
DICOM_GETIMAGE_FROM_FLTLOAD | [0x8000] Internal Use Only. |
DICOM_GETIMAGE_KEEP_COLOR_PALETTE | [0x10000] When Photometric Interpretation is 'PALETTE COLOR', returns a grayscale image with a color palette. Without this flag, 'PALETTE COLOR' images are converted to 24-RGB |
DICOM_GETIMAGE_RESERVED1 | [0x20000] Internal Use Only. |
Value | Meaning |
---|---|
DICOM_SUCCESS | The function was successful. |
>0 | An error occurred. Refer to Return Codes. |
If you need to use a callback function, use the L_DicomGetImageListEx function.
As an example, if you wish to load 50 images starting with the 50th frame in the Pixel Data, call this function with nIndex set to 49 (the 50th frame in a zero-based index) and nCount set to 50.
If pElement is NULL, you can retrieve a image list of all images within the Data Set. To do this you must call L_DicomGetCountImage with pElement set to NULL to determine the number of images in the Data Set and set the nCount parameter in L_DicomGetImageList to this value.
If DICOM_GETIMAGE_ALLOW_RANGE_EXPANSION is set in uFlags, consider the following example:
If the dataset has the following attributes:
Attribute | Value |
---|---|
Bits allocated | 16 |
Bits stored | 12 |
Pixel Range | 0 - +4095 |
Pixel Representation | Unsigned (0) |
Photometric Interpretation | MONOCHROME2 |
Rescale Slope | 1 |
Rescale Intercept | -1024 |
After applying the rescale slope and the intercept:
The new pixel value range (1024 to 3071) cant be represented with the current bits stored (12 bits), which can represent values in the range (2048 to 2048). In this case the function will change the high bit inside the image handle to be 12 instead of 11 (bits stored becomes 13), which can represent values in the range (8192 to 8191).
Please note that the function wont be able to update the high bit and/or low bit if the number of bits stored was already equal to the number of bits allocated.
If the DICOM dataset has a Multi-frame Functional Groups module, some VOI LUT information will be read from the correspondingFrame VOI LUT Sequence, and some Modality LUT information will be read from the corresponding Pixel Value Transformation Sequence.
The specific elements that are read is shown below:
Tag | Name |
---|---|
(0028,9132) Frame VOI LUT Sequence Child Elements: | |
(0028,1050) | Window Center |
(0028,1051) | Window Width |
(0028,1055) | Window Center & Width Explanation |
(0028,9145) Pixel Value Transformation Sequence child elements: | |
(0028,1052) | Rescale Intercept |
(0028,1053) | Rescale Slope |
(0028,1054) | Rescale Type |
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.
Required DLLs and Libraries
Win32, x64, Linux.
This example fills a bitmap list with all images from the Data Set
L_INT DicomGetImageListExample(L_VOID)
{
HDICOMDS hDS;
HBITMAPLIST hList;
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;
}
nRet = (L_UINT16) L_CreateBitmapList(&hList);
if (nRet != SUCCESS)
{
L_DicomFreeDS(hDS);
return nRet;
}
nRet = L_DicomGetImageList(hDS, NULL, hList, 0, ELEMENT_INDEX_MAX, 0, 0);
if (nRet != DICOM_SUCCESS)
{
L_DicomFreeDS(hDS);
return nRet;
}
nRet = (L_UINT16) L_DestroyBitmapList(hList);
if (nRet != SUCCESS)
{
L_DicomFreeDS(hDS);
return nRet;
}
L_DicomFreeDS(hDS);
return DICOM_SUCCESS;
}