Development
Responsive Picture / srcset Art Direction Builder
Build complete <picture> markup with art-directed crops: per-breakpoint <source media> elements, 1x/2x density candidates or {w}-template width descriptors, optional AVIF/WebP format layers, sizes handling, CLS-safe width/height, plus HTML and JSX flavors with spec-based lint notes.
html· HTML resultOpen tool
Quick start
Call this tool from your code in three languages.
cURL
# 1) Request a presigned URL → returns { uploadUrl, storageKey }
curl -X POST 'https://api.elysiatools.com/api/upload/presign/responsive-picture-srcset-art-direction-builder' \
-H 'Content-Type: application/json' \
-d '{"filename":"variantImages.ext","contentType":"application/octet-stream","size":12345}'
# 2) PUT the file bytes directly to the presigned uploadUrl
curl -X PUT '<presigned uploadUrl>' \
--data-binary @/path/to/file.ext
# 3) Call the tool, passing the returned storageKey for each file field
curl -X POST 'https://api.elysiatools.com/en/api/tools/responsive-picture-srcset-art-direction-builder' \
-F 'sources=768 /img/hero-mid.jpg
1280 /img/hero-wide.jpg' \
-F 'variantImages=uploads/2026/01/01/your-tool-1700000000000-abc123.ext' \
-F 'descriptorMode=density' \
-F 'densities=1x,2x' \
-F 'sizesAttr=(min-width: 1024px) 960px, 100vw' \
-F 'fallbackUrl=/img/hero-mobile.jpg' \
-F 'altText=Fresh sourdough loaves on a marble counter' \
-F 'formatLayer=none' \
-F 'flavor=html' \
-F 'lazyAttrs=true'