MB86277 'Mint'

Mint is a low end GDC without a geometry engine, but is still capable of rendering 3D graphics. It is available in a QFP package. With a 100MHz internal operation clock, it has sufficient power to draw sophisticated 3D graphics while not wasting excessive power. The video input unit is capable of accepting TV tuner, DVD player or camera signals in PAL or NTSC video formats (ITU656 format). Video pictures of diverse resolution and frame frequency rate, in either progressive or interlaced modes, can be grabbed, scaled down and displayed picture-in-picture.

Using the new Alpha-map, the video picture can be blended smoothly together with rendered graphics. The alpha map can be freely assigned to any of the six layers and allows the assignment of 8 bits per pixel, enabling each pixel to be mixed to control transparency to a much more defined degree. In addition, all layers can be blended at a fixed ratio of 256 levels.

To enhance Bit BLT (Bit Block Transfers) operations, this feature can now be combined with alpha-mapping. With this function, any bitmap can be copied from any source location (CPU- or Video-memory) and can be copied onto a layer with an independent alpha-map. Software routines which make use of this function can greatly improve image quality (for example anti-aliasing over a moving background).