# What Seedream 4.0 added to image creation

> ByteDance combined image generation and editing, with reference images and higher-resolution output.

Source: https://fullbytedeveloper.com/blog/seedream-four-image-editing-release
Originally posted: 2025-09-21
Published here: 2026-11-06

ByteDance released Seedream 4.0 on 2025-09-09. Its announcement described one architecture for image generation and editing, accepting text, images or combinations of both. Supported tasks included single-image edits, multi-image edits and composition. [1]

## Read the speed claim accurately

ByteDance compared the model's speed with Seedream 3.0 and reported a substantial improvement. That comparison does not establish the social caption's claim that it was the fastest image model across every provider and workload. The release also described output up to 4K. [1]

## Test an edit you can inspect

Use an image you have permission to edit. Ask for one specific change, while naming details that should stay fixed. Check faces, text, object positions and lighting after generation.

For a fair comparison with another image tool, keep the input and requested output consistent. Record usable results and retries as well as generation time. A fast first result has limited value if it needs extensive repair.

## Sources

1. [ByteDance Seedream 4.0 launch](https://seed.bytedance.com/en/blog/seedream-4-0-officially-released-beyond-drawing-into-imagination)

## Original posts

- [Instagram post](https://www.instagram.com/fullbytedeveloper/p/DO3dlb7DDfj/)