ImageGear API is a set of C functions, callback function declarations, structures, enumerations, and macros.
The central element in ImageGear API is the single page image handle: HIGEAR. It can contain raster or vector data for a single image page. The majority of ImageGear API functions take HIGEAR as a parameter. See Single-Page Images for more information.
ImageGear also allows working with multi-page documents. See Multi-Page Documents for more information.
The most common way to obtain a HIGEAR is to load a page from an image file, located on a disk, in a memory buffer, or at an Internet location. You can also create a blank HIGEAR, acquire an image from a scanner, or paste an image from clipboard. See the following sections for details:
Once the image is in memory, you can process it in a variety of ways, for example: save to a disk file, a memory buffer, or an internet location, display, print, apply image processing operations, convert the image to a different pixel format, access image pixels directly, annotate the image, or recognize text in the image. See the following sections for details:
- Saving Images
- Displaying Images
- Processing Images
- Color Management
- Accessing Image Pixels
- Annotating Images
- Optical Character Recognition
ImageGear also provides advanced metadata (non-image data) support, including support for TIFF, EXIF, XMP, IPTC, Photoshop, and other types of metadata. Note, however, that ImageGear does not store metadata with a HIGEAR or HMIGEAR handle, but instead provides callbacks to get or set (add) metadata during image loading and saving. It is the application's responsibility to store the metadata between loading and saving an image. See Non-Image Data Processing for details.
Several image file formats have features that are not used by other file formats. ImageGear provides specialized API for these formats. Please see Advanced Image Formats for details.
See these additional topics for information on other important aspects of ImageGear API: