virtual L_INT LBitmapBase::SetAlpha(LBitmapAlpha)
Replaces the class object's existing alpha channel data or creates new alpha channel data in the class object's bitmap using the specified class object's bitmap.
A bitmap object that has an allocated bitmap to be set as the alpha channel for the calling objects bitmap.
Value | Meaning |
---|---|
SUCCESS | The function was successful. |
< 1 | An error occurred. Refer to Return Codes. |
Typically, an alpha channel contains a mask that is used for transparency. This function, together with the LEADTOOLS region processing functions, lets you use the alpha channel to implement transparency.
Only 16- and 32-bit images can have an alpha channel. If pBitmap references a bitmap of any other color resolution, this function converts the pBitmap bitmap to 32-bit before it replaces the alpha channel. (If you want 16-bit, you should change it using LBitmapBase::ColorRes, if necessary, before calling this function.)
The pAlpha bitmap does not have to be grayscale. This function converts the data from the pAlpha bitmap to the necessary grayscale or 1-bit format as it replaces the alpha channel in pBitmap. (The pAlpha bitmap, itself, remains unchanged.)
Note: The LBitmapAlpha parameter is passed by reference, and is a required parameter.
This function does not support signed data images, unless they are DICOM images. It returns the error code ERROR_SIGNED_DATA_NOT_SUPPORTED if a signed data image that is not a DICOM image is passed to this function.
Win32, x64.
L_INT LBitmapBase__SetAlphaExample()
{
L_INT nRet;
LBitmapBase MyBitmap,Bitmap2;
MyBitmap.SetFileName(MAKE_IMAGE_PATH(TEXT("image1.cmp")));
nRet =MyBitmap.Load(32);
if(nRet !=SUCCESS)//load at 32 bit per pixel
return nRet;
nRet =Bitmap2.CreateAlphaBitmap(MyBitmap);
if(nRet !=SUCCESS)
return nRet;
nRet =MyBitmap.Load(MAKE_IMAGE_PATH(TEXT("image2.cmp")),32);
if(nRet !=SUCCESS)
return nRet;//load at 32 bit per pixel
nRet =MyBitmap.SetAlpha(Bitmap2);
if(nRet !=SUCCESS)
return nRet;
return SUCCESS;
}
Help Collections
Raster .NET | C API | C++ Class Library | HTML5 JavaScript
Document .NET | C API | C++ Class Library | HTML5 JavaScript
Medical .NET | C API | C++ Class Library | HTML5 JavaScript
Medical Web Viewer .NET
Multimedia
Direct Show .NET | C API | Filters
Media Foundation .NET | C API | Transforms
Supported Platforms
.NET, Java, Android, and iOS/macOS Assemblies
Imaging, Medical, and Document
C API/C++ Class Libraries
Imaging, Medical, and Document
HTML5 JavaScript Libraries
Imaging, Medical, and Document
Your email has been sent to support! Someone should be in touch! If your matter is urgent please come back into chat.
Chat Hours:
Monday - Friday, 8:30am to 6pm ET
Thank you for your feedback!
Please fill out the form again to start a new chat.
All agents are currently offline.
Chat Hours:
Monday - Friday
8:30AM - 6PM EST
To contact us please fill out this form and we will contact you via email.