Perpaletteentry

Perpaletteentry is a term encountered in discussions of color palettes and image processing to describe a data organization where information for each palette entry can be stored and manipulated independently, rather than applying changes uniformly to the entire palette. It is not a standardized specification, but a concept that appears in libraries, formats, and documentation that deal with indexed color, palette-based rendering, or per-entry metadata.

In a perpaletteentry approach, a palette consists of an array of entries, each potentially containing color data (such as RGB or RGBA) plus optional per-entry attributes. These attributes might include per-entry alpha, usage flags, priority levels, or custom metadata. The key idea is that operations can target individual entries—such as adjusting contrast for a single color, marking a color as reserved, or associating it with a specific display role—without affecting other entries.

Use cases include traditional indexed-color images (GIF, PNG with a palette), where some formats or tools expose per-entry metadata, as well as advanced quantization or color-management workflows that require per-entry control, and GUI theming systems that map UI elements to specific palette colors. It is often contrasted with models that apply edits uniformly across the entire palette or operate solely on color values without per-entry context.

Implementation considerations include increased data size due to per-entry metadata, potential encoding complexity, and the need for clear interoperability rules to ensure consistent interpretation of per-entry fields across tools and formats.