AntiAlias

Synopsis

The anti_alias macro performs full-color antialias filtering and 2:1 size reduction on full colour ARGB byte images.

Input Ports

Name	Type	Description

in	Image_ARGB	original image that should be downsampled.

Output Ports

Name	Type	Description

out_image	Image_ARGB	downsampled and smoothed image.
out_obj	GDobject	Directly renderable output object.

Description

The anti_alias macro downsamples an image using a Gaussian 3x3 convolution filter. This produces an antialiasing effect, reducing jagged edges. It also produces an output image that is half the size of the input image in each dimension. For instance a 512x512 image becomes a 256x256 image after antialiasing. There are no parameters associated with this module, and hence no user interface.

This module is a conversion of the AVS5 "antialias" module. The module implementation is now in C++. The low-level code operates on simple byte arrays rather than fields.

Inputs

Full colour 2D image that is to be filtered by the module. The image should be a 2D uniform grid of type Image_ARGB. The read_image module outputs data of this type.

Outputs

out_image

Full colour 2D image after filtering by the module. The modified image also as a type of Image_ARGB.

out_obj

The GDobject version of the output, suitable for direct connection to the viewer. A 2D viewer is recommended.

Utility Macros

The anti_alias macro makes use of the AntiAliasCore low-level module.

Example

The AntiAlias project provides two example applications. Both of these read and filter the 'mandrill' image. The AntiAliasEg1 application displays the original and filtered images in the same scene so that the effect of the downsampling can be examined. The AntiAliasEg2 application displays the original and filtered images in different scenes so that the effect of the filtering can be examined.

Files

iac_proj/a_alias/ant_mods.v contains the V definition of the AntiAliasCore module.

iac_proj/a_alias/ant_macs.v contains the V definitions of the anti_alias user macro and the AntiAliasEg1 and AntiAliasEg2 example applications.

Other Notes

The low-level AntiAliasMods library containing the module does not specify a process. By default the express process will be used.

Authors

Sabreen Vig, Larry Gelberg, Ian Curington
Advanced Visual Systems, Inc.
Andrew Dodd
International AVS Centre

Contact

International AVS Centre
Manchester Visualization Centre
Manchester Computing
University of Manchester
Oxford Road
Manchester
United Kingdom
M13 9PL