Choosing the appropriate image format in DITA is essential to ensure optimal quality, compatibility, and rendering in various output formats. Consider factors like content, purpose, and target media to determine whether to use common formats like PNG, JPEG, or SVG.

Selecting the Right Image Format

Selecting the right image format in DITA involves accounting for content and quality, compression, transparency, and resolution.

Content and Quality

Choose formats like PNG for graphics with sharp lines and text, JPEG for photographs or images with gradients, and SVG for vector graphics. PNG and JPEG are raster formats, while SVG is scalable and ideal for content that must adapt to different screen sizes.

Compression

Consider image compression. JPEG uses lossy compression, reducing file size but potentially lowering quality. PNG and SVG offer lossless compression, preserving image quality but resulting in larger file sizes.

Transparency

If an image needs transparency, opt for PNG, which supports alpha channels. JPEG does not offer transparency, and SVG can include transparent elements.

Resolution

Match image resolution to the intended output. Higher resolutions are suitable for print, while web content may require lower resolutions to optimize loading times.

Example

An organization is creating documentation for a piece of software with a variety of visual elements. They want to include screenshots of the user interface. In this case, they would choose to use PNG for its crisp lines and clear text, ensuring the software’s interface is accurately represented. For product photos or images of hardware, JPEG might be more suitable to manage file size while preserving reasonable quality. If they need to include an interactive chart that should appear sharp at any screen size, SVG is the ideal choice due to its scalability. Each format aligns with the content type, purpose, and target output, ensuring that the DITA documentation is visually effective.