Ideogram 4.5 edit images: 5 sources, first is edited, vs Sume

Ideogram 4.5 edits through the same generate endpoint: you upload up to 5 source images as images (max 25 MB each; JPEG, PNG or WEBP), and the first one is edited while the others are extra references. It is multipart/form-data only. Sume takes references as public HTTPS URLs in input_references, so there is no multipart upload step in the request.

Ideogram facts are from its Ideogram 4.5 reference; Sume facts from the Image API and catalog code, read 2026-10-01.

What are Ideogram 4.5's source image rules?

How does Sume take images?

Reference URLs must be public HTTPS; localhost, private-network and non-HTTPS URLs are rejected before submission. Each entry in input_references is an object with type: "image_url" and image_url.url. How many references a model takes comes from its catalog entry: in the code, edit-capable models default to a max_images of 4 unless an entry overrides it, and the ideogram-v3 entry does not. Models whose input_references descriptor is {"min": 0, "max": 0} are text-to-image only.

Which image is the edit target on Sume?

The Image API docs I read do not define an ordering rule like Ideogram's first-is-edited, and Sume's Ideogram entry is Ideogram V3, not 4.5. So say it in the prompt: name which reference is the picture to change and which are style or content guides.

Order is the only portability habit that carries over: a client that always puts the picture to change first behaves the same under Ideogram's rule and under your own prompt wording on Sume.

What do I change when moving a request?

Replace the multipart upload with hosted URLs: put each file somewhere public over HTTPS, then list them under input_references. Drop any field the Sume model does not list, because it returns 400 unsupported_parameter. Check GET /v1/images/models for the reference count before sending more than one or two images. The upload limits on Ideogram's other endpoints are in Ideogram multipart upload limits.