Building a simple database is the best way to see how QPix fits in your projects. Reading this manual further will give you more information which you can convert to inspiration and build great image databases. The material in this chapter is coarsely based on the demo database that is included, non compiled, in the QPix distribution package.
A basic image database needs a handful of image-related functions. These include the identification of image files, reading of image properties, creation and compression of thumbnails, storage of thumbnails and textual information in the datafile, display of thumbnails, and access to the original media.
We will now see how these can be accomplished with 4D and QPix. For storing image information in the database we will use the [Images] table that has the following structure:
xThumbnail_ |
Picture | The image's thumbnail, compressed with QuickTime |
FullPath |
Text | The full pathname to the original image on disk |
Width |
Longint | The image's width |
Height |
Longint | The image's height |
Depth |
Longint | The image's color depth in bits |
HorzRes |
Longint | The image's horizontal resolution |
VertRes |
Longint | The image's vertical resolution |
We are now ready to write the code. The steps are the following: