Formats and responsive art direction
WebP and AVIF are supported by every current major browser and usually produce much smaller files than JPEG at similar quality. Serve them through a picture element or an image service that negotiates the format, with a fallback where older clients matter. Resolution switching, through srcset and sizes, sends each device an appropriately sized file. Art direction goes further: a picture element with media queries can send a different crop to a phone, so a wide hero with the product on the right becomes a tight vertical composition on mobile. Generation makes that second composition cheap, and it is usually better than any crop of the desktop image.
Core Web Vitals and the hero image
Google's Core Web Vitals set good thresholds at the 75th percentile of page loads: Largest Contentful Paint within 2.5 seconds, Interaction to Next Paint within 200 milliseconds, and Cumulative Layout Shift of 0.1 or less. INP replaced First Input Delay in March 2024. The hero image is often the largest contentful element, so never lazy-load it, give it a high fetch priority, size it for its slot and set width and height so the layout does not jump. Generated images arrive as large PNGs by default. Convert and compress them on the way into the CMS, or one new banner can undo a performance programme.
Alt text, accessibility and structured data
WCAG 2.2 success criterion 1.1.1, at Level A, requires a text alternative for every meaningful image, and decorative images should carry empty alt text so screen readers skip them. The European Accessibility Act, Directive (EU) 2019/882, has applied since 28 June 2025 to many consumer e-commerce services. Generated alt text needs review: it tends to list what is visible instead of why the image is there, and misses product names. Structured data helps search engines read the page: Product markup with images and offers, and for articles Google asks for images in 16:9, 4:3 and 1:1. Keep IPTC and C2PA provenance metadata on generated images.
CMS workflows that keep control
A CMS that receives generated content at volume needs a content model that enforces the basics: alt text as a required field, focal points for automatic crops, locale fields for each market, and approval states before anything publishes. Images should come from the DAM as the source of truth rather than from downloads on someone's laptop. Synthetic White connects to DAM, CMS and PIM systems, so approved images and copy move into the site without manual downloads, while the studio keeps the approval trail and a record of which model made each asset. Google's spam policies target scaled content abuse, however it is produced, so every generated page still needs an editor's judgement.
Updated 25 September 2026