Knitwear flat-lay to a moving on-model ad: three colorways for $5.92

A knitwear flat-lay becomes a moving on-model ad in two steps: an image edit that places the garment on a model, then an image-to-video clip that animates that still. For three colorways of one sweater, the cost on Sume is 3 x $0.0835 for the stills plus 3 x $1.89 for 5-second 720p Seedance 2 clips, which is $0.2505 + $5.67 = $5.9205, or $5.92 (prices read 2026-10-05). Knits are a hard case, since stitch pattern and neckline shift when a model moves, so the plan below puts a check between the two steps.

Step one: the on-model still

gpt-image-2.5 accepts up to 16 reference images, per the image docs. Send the flat-lay as a reference and describe the model, the pose and the setting. An edit with one reference at high quality is $0.0835 on Sume; medium is $0.0209 and low is $0.0094, so you can draft cheaply and finish at high. The existing guide to flat-lay to on-model images covers the prompt.

The check between steps

Motion multiplies any error in the still. If the neckline, cuff or pattern is wrong in the image, a clip will carry it for five seconds. Compare the still against the flat-lay at full size before paying $1.89. Reject any still where the garment differs from the product, because a product ad that shows a different sweater is a returns problem.

• Neckline and hem match the flat-lay.
• Stitch pattern and colour are the product's, not a lookalike.
• Hands, cuffs and sleeves look plausible at full size.
• The model's pose leaves room for a slow camera move, not a big turn.

Step two: the clip, and the bill

Pass the approved still as the first_frame on POST /v1/videos with seedance-2, 5 seconds, 720p and 9:16 (videos docs). Ask for one slow move, such as a gentle turn or a dolly in; keep the prompt short.

If you need the garment fitted to a specific body, rather than a model who wears it, compare virtual try-on and virtual fitting; for a wider shop workflow, see one garment photo to five shop assets. Retakes are the budget risk: one retake per colorway nearly doubles the motion line to $11.34 and the total to $11.59.