L_TwainSetImageUnit
#include "lttwn.h"
L_LTTWN_API L_INT L_TwainSetImageUnit(hSession, nUnit)
HTWAINSESSION hSession; |
/* handle to an existing TWAIN session */ |
L_INT nUnit; |
/* image unit */ |
Sets the image unit value used to transfer images from the current TWAIN source.
Parameter |
Description |
hSession |
Handle to an existing TWAIN session. This handle is obtained by calling the L_TwainInitSession function. |
nUnit |
Specifies the unit value to set. For more information on possible values, refer to www.twain.org/download.htm and click on TWAIN Specification (Version 1.9). |
Returns
SUCCESS |
The function was successful. |
< 1 |
An error occurred. Refer to Return Codes. |
Comments
This function internally sets the image unit capability ICAP_UNITS. For more information on this capability, refer to www.twain.org/download.htm and click on TWAIN Specification (Version 1.9).
To obtain the current image unit value, call the L_TwainGetImageUnit function
This function should be called after calling the L_TwainStartCapsNeg function and before calling the L_TwainEndCapsNeg function.
Required DLLs and Libraries
LTTWN For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application. |
See Also
Example
L_INT TwainSetImageUnitExample(HTWAINSESSION hSession) { L_INT nRet = SUCCESS; nRet = L_TwainStartCapsNeg (hSession); if(nRet != SUCCESS) return nRet; L_INT nUnit; nRet = L_TwainGetImageUnit (hSession, &nUnit); if (nRet == SUCCESS) { if (nUnit != TWUN_INCHES) { nRet = L_TwainSetImageUnit(hSession, TWUN_INCHES); if(nRet != SUCCESS) return nRet; } } else return nRet; L_INT nBPP; nRet = L_TwainGetImageBitsPerPixel (hSession, &nBPP); if (nRet == SUCCESS) { if (nBPP != 24) { nRet = L_TwainSetImageBitsPerPixel (hSession, 24); if(nRet != SUCCESS) return nRet; } } else return nRet; nRet = L_TwainEndCapsNeg (hSession); if(nRet != SUCCESS) return nRet; return SUCCESS; }