A product cutout can look clean on white and still show a halo as soon as you put it on a dark background.
On November 9, ByteDance Seed introduced Seedream 5.5, an image model that can generate and edit images with transparency. It also showed the model carrying details through sequences of up to 100 editing rounds. Those examples come from ByteDance; they don’t show how every image will hold up.
What native transparency changes
The model page describes RGBA output, which adds a channel for opacity alongside red, green, and blue. That lets a pixel be partly transparent. Hair, frosted glass, or a soft shadow can keep their edges when placed on a different background. Whether those edges look good still depends on the output and the format you export.
Start with a subject that has a soft edge and a hard edge in the same frame. Export it in a format that preserves alpha, such as PNG. Place it over white, charcoal, and a saturated color. Inspect the edges at full size before deciding whether it can replace manual masking.
Look for drift in the areas you did not edit
Save the original and each result. Ask for five or ten changes to one part of the image, such as swapping a bottle label. After each edit, inspect a fixed area elsewhere, such as the bottle cap or a logo. If the files share dimensions and alignment, compare the same crop from each lossless export. Otherwise, use a visual comparison and record any crop or shift.
The release shows two features worth testing separately. A clean alpha edge tells you little about whether the image will keep its details after another ten revisions.
Abdessalam Alaoui
I'm Abdessalam Alaoui, founder of Musthave.AI. I write practical guides to AI models, tools, generative media.
