为何含结构化数据的AMP页面需1200px宽图片而非AMP仅需696px？

Great question—this is a common point of confusion for folks working with AMP and standard web pages. Let’s break down the key reasons behind this difference:

• High-Density Mobile Screens Are the Norm
  Most modern mobile devices have high-resolution (Retina or similar) displays, where each "pixel" on the screen is made up of 2-4 physical pixels. A 1200px-wide image will scale down cleanly to 600px (for 2x density) or 400px (for 3x), ensuring sharp, crisp visuals without pixelation. A 696px image, by contrast, would only scale to 348px on 2x screens—too small for the prominent display slots AMP often occupies in mobile search.

• AMP’s Prominent Search Result Placement
  AMP pages frequently appear in premium mobile search positions like the Top Stories carousel, large featured cards, or image-rich snippets. These slots use larger image displays to grab user attention, and a 1200px minimum ensures the image fills the space without stretching or looking blurry. Non-AMP pages typically show up in standard list entries with smaller thumbnail spaces, so 696px is sufficient for those contexts.

• Consistent Cross-Device Experience
  AMP’s core goal is to deliver a uniform, high-performance experience across all mobile devices. By requiring a large source image, AMP’s automatic image optimization system can generate perfectly sized versions for every device—from small phones to large tablets—without you having to manually create multiple image variants. This eliminates the risk of serving undersized images to larger screens.

• AMP’s Built-in Image Optimization Does the Heavy Lifting
  Don’t worry about users loading a full 1200px image on their phones! AMP automatically serves appropriately compressed, resized versions of your image based on the user’s device. The 1200px minimum just gives AMP’s optimization pipeline enough raw material to create these tailored versions, ensuring quality no matter the screen size.

内容的提问来源于stack exchange，提问作者jnth132