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Images and Bitmaps

Images.htmlImages are representation of pictures, from wee icons to screen-filling murals. HTK's images are what in Tk is called a photo. An image is created with the function

Once created, an image can be attached (via the photo configuration, class HasPhoto) to labels, buttons, and canvas items. The configuration gives the image's data, either via the filename configuration, where a file is specified which contains the image data, or via the imgData configuration, which passes the data directly as Base64 encoded string. (You can use e.g. the mimencode(1) utility to produce such a string.) As can be seen from the Format datatype, HTK supports GIF, PPM and PGM formats. The latter method of giving the image data is preferable, since it makes the compiled executable independent of image data files; if you pass a filename, you need to make sure that the image file is to be found at that path during the runtime of the program!

BitMap.htmlBitmaps have a foreground and a background. The difference between images and bitmaps is that bitmaps are more versatile, e.g. you can change the foreground and background, but only have two colours. There is also a number of predefined bitmaps (Hourglass, Questhead, etc.) Apart from that, bitmaps are rather boring.

Christoph Lueth
Wed May 29 13:20:38 MEST 2002