From Tracker Software PDF SDK
This method loads an image from the selected file.
HRESULT Load([in] LPWSTR sImagePath, [in, defaultvalue(0)] ULONG nFlags);
- [in] Value of LPWSTR is the null-terminated file name string.
- [in, defaultvalue(0)] The following flag can be used to specify how the image will be loaded.
Returns S_OK if the operation was successful, and will return an error code if it fails.
By default Load opens the image file, acquires information about all pages, decodes all of them, and closes the file. This is a good approach for single page files, but when dealing with large multi-paged files, this may cause unnecessary memory usage and performance degradation. To avoid this situation, Load should be called with the ImageLoad_Deferred flag. In this case, the image file will be analyzed, information about its pages will be acquired, but actual page data will not be decoded immediately.