The central element in ImageGear API is the single-page image handle: HIGEAR. The majority of ImageGear API functions take HIGEAR as a parameter. HIGEAR encapsulates the following data:
- DIB information, such as dimensions, color space, and channel depths. See DIB Information for more details.
- Image pixels (if HIGEAR contains a raster image). Usually, you do not need to access the image pixels directly. You can load, display, process, save images, and do other operations using high-level API that accesses image pixels internally. If you need to access image pixels directly, see Accessing Image Pixels for details.
- Vector data (if HIGEAR contains a vector image). See Working with Vector Images for details.
- Image display attributes. See Displaying Images for details.
- Image orientation. See Image Orientation for details.
- Color profile (optional). See Using Color Profile Manager for details.
- Non-rectangular Area of Interest (optional). See Region of Interest Processing for details.
- Format-specific information (for DICOM and FlashPix).
- Extra channel information (optional). See Spot and Mask Channels for details.
Usually you create a HIGEAR handle by loading an image from a disk file, or from memory. See Loading Images for details. You can also create a new HIGEAR handle using IG_image_create, or import a Windows DIB into HIGEAR using IG_image_DIB_import.
When HIGEAR is no longer used, you must delete it using IG_image_delete.
A HIGEAR can contain raster data or vector data, but not both (except for the case when vector data contains raster entities; however, such raster data is only accessible via the vector API). Vector images are further subdivided into CAD, PDF, and XPS. Use IG_image_is_raster, IG_image_is_vector, IG_image_is_CAD, IG_image_is_PDF, and IG_image_is_XPS to find out the type of image represented by a HIGEAR.