Ideogram API upload limits (10, 25, 50 MB) vs Sume image URLs

Ideogram's limit depends on the endpoint: 10MB to describe an image, 25MB to remove a background, and 50MB for the Topaz Text Refine upscaler, all as multipart uploads only. Sume's image routes take a public HTTPS URL instead of a file, so there is no per-file upload cap in the docs read; the request body itself has an API limit and must be JSON.

Ideogram figures are from the three endpoint pages, read 2026-10-01.

What are Ideogram's caps?

How do Sume inputs differ?

Input image and video URLs must be fetchable public HTTPS URLs. Localhost, private-network URLs, non-HTTPS URLs, signed or private URLs, and mismatched content types are rejected before generation submission (asset library docs). Image reference URLs follow the same rule (image docs). You host the file; Sume fetches it.

Which errors can a bad request return?

From the errors table: 413 payload_too_large when the request body exceeds the configured API limit, and 415 unsupported_media_type when the body was not application/json (the response carries details.received_content_type). If Sume cannot fetch your URL you may see image_not_fetchable or input_media_unreachable: check the URL is public HTTPS, then retry.

What should I do when moving a pipeline over?

Replace the multipart upload step with a host step that yields a public HTTPS URL, then send JSON. Do not post file bytes to a Sume image route; a non-JSON body returns 415. For a related limit post, see Format run 413 payload too large.