Image Converter Overview

Provides a simple interface for common image-related operations. Specifically it provides support for:

• simple bitmap rotation in 90 degree increments

• arbitrary re-scaling of a bitmap

• conversion of an image to/from a bitmap where the image may be file-based or descriptor-based.

The media server supports the following image formats as standard:— jfif (jpg), mbm, bmp (1, 4, 8 or 24 bpp), Wbmp, Ota, Png, Wmf, Wmf Apm, Wmf Clp, TIFF/F (both byte orders), gif (87a and 89a), Ico.

The rotation, re-scaling and conversion operations are handled by the media server.

Clients using this API must have an active scheduler running in their thread because the implementation of the API uses active objects and callbacks.

The API has 3 key concepts: Rotation, re-scaling and format conversion.

The API supports simple clockwise rotation operations on a bitmap in 90 degree increments. The bitmap is resized, if necessary.

The API supports arbitrary re-scaling of a bitmap. The scaling factor is determined by the relative sizes of the source and target bitmap. The aspect ratio can be maintained, if required.

Format conversion operations are provided. Conversions can be done:

• from a file-based image to a bitmap

• from a bitmap to a file-based image

• from a descriptor-based image to a bitmap

• from a bitmap to a descriptor-based image

• from one bitmap to another bitmap

Operations to or from a bitmap include size and colour depth conversions. Conversions to a bitmap may also include a down scaling operation.