Canvas.

Canvas provides a useful rendering model for digital frame composition: create a drawing surface, place image content, add graphic layers, and export a bitmap. The important distinction is between the source rectangle being read and the destination rectangle being drawn. That relationship controls cropping and scaling. Intrinsic image dimensions also differ from the size of a preview shown in a page, so calculations should use the actual source information rather than the appearance of a small editor window.

The reading here uses that model to explain repeatable photo layouts, borders, backgrounds, and clipping. Focus on operation order and the geometry recorded with an output, especially when a person adjusts the crop. The image composition overview connects canvas concepts to broader frame workflows. A practical review should compare the preview with the exported pixels and test transparent content against several backgrounds. Keep source assets and layout parameters separate so a design can be reproduced at another resolution.