Retexture a product photo with FLUX.2 pro: prompt and call

To retexture a product photo on Sume, send the photo as a single input_references item to black-forest-labs/flux.2-pro, name the material to change, list what must not change, and set aspect_ratio: "auto" so the output matches the source. Black Forest Labs lists retexturing among the strengths of its FLUX.2 line.

Why retexturing is a good edit

The BFL FLUX.2 [max] page lists retexturing of objects and environments, consistent product photos and iterative editing among its use cases. Those claims are about the max tier. Pro is the tier the same page calls affordable and production-grade, so treat the retexturing strength as plausible for pro but verify it on your own product.

The call

The reference must be a public HTTPS URL. Sume rejects localhost, private-network and non-HTTPS addresses. Leave out seed, because v1 does not serve it and returns 400 unsupported_parameter.

curl -X POST "https://api.sume.com/v1/images" \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"black-forest-labs/flux.2-pro","prompt":"Replace the leather body of the bag with natural canvas. Keep the stitching layout, handles, metal hardware, shadow and background identical.","aspect_ratio":"auto","input_references":[{"type":"image_url","image_url":{"url":"https://media.sume.com/uploads/bag.jpg"}}]}'

Checking the result

Put the original and the edit side by side and look at the three places edits usually drift: logo shape, hardware count, and the edge between product and background. If the logo changes, retry with the logo called out by name in the preserve clause. If the edit needs an exact region, FLUX does not take mask_url on Sume; use ChatGPT Image 2.5 for masked edits.

Cost and speed

Read the pricing line from GET /v1/images/models/black-forest-labs/flux.2-pro/endpoints before a batch. If a call exceeds the 30-second wait it returns 202 with a job envelope; poll the status URL, then fetch the result.

Prompt anatomy

A retexture prompt has three parts:

• What changes: one material, named.
• What stays: shape, hardware, logo, shadow, background.
• How to read the result: compare against the original at 100 percent zoom.