Critique

Windows Picture and Fax Viewer

Overview

Image viewer built in Windows XP that is capable to view basic picture formats.

Key weakness

The Image viewer is known to have difficulty rendering PNG (Portable Network Graphics) images correctly.

Root cause

Even though PNG images are acceptably displayed, it sometimes causes entire lines to not be rendered at a high zoom level, making it confusing when examining critical image data. This is most likely due to a poor implementation of the PNG compression algorithm.

Suggested improvements

1. Review the quality requirement in order to fix the file rendering problem
2. Re-implement the decompression algorithm with a quality and efficiency driven objectives (rather than poor and dashed off implementation)
3. Test the feature before finalizing it