BYTEDANCE

Bytedance Seedream 4.5 is an AI-powered image editor that integrates image generation and sophisticated image editing into a unified architecture. The model is designed to transform existing images and compositions using natural language instructions, removing the need for manual masking or layer-based workflows. Seedream 4.5 accepts both images and text as input, enabling users to reference up to 10 images concurrently for complex, context-aware multi-source editing tasks. Example use cases include creating multi-image product composites, prototyping design layouts with text overlays, and maintaining brand consistency across varied visual content.

One of the core strengths of Seedream 4.5 is its ability to execute multi-source compositions by selectively copying, repositioning, or modifying elements from one image to another based on spatial instructions provided in plain language. For instance, a prompt might specify to "replace the product in Figure 1 with that in Figure 2" or "copy the title text from Figure 3 to the top of the screen with clear contrast," allowing the model to interpret and perform the requested edits with spatial awareness and without explicit layer selection or masking.

The model ensures that transformations such as object replacement or text overlay maintain contextual integrity, such as preserving lighting, depth, and perspective across different sourced elements. This unified approach is particularly suited for users in e-commerce, design, or marketing who require fast and consistent integration of products, text, or brand elements across diverse images without tedious manual editing.

Technically, Seedream 4.5 processes up to 10 reference image inputs per edit. If more than 10 images are provided, only the last 10 will be used. The model supports PNG image output, delivered via URL or data URI. Outputs are configurable up to 4 megapixels (2048x2048 maximum resolution) with dimension flexibility between 1920 and 4096 pixels on each axis, permitting large and high-fidelity results to match diverse production needs. The input text prompt guides editing or generation actions, and batch control parameters allow users to generate between 1 and 6 images per request, with optional multi-image variations for each generation cycle. The total number of images (inputs plus outputs) in a single request must not exceed 15.

On performance, Seedream 4.5 typically processes each edit in approximately 60 seconds when running on the fal infrastructure. The supported input format is image URLs for images and plain text for instructions. Through its API, users can further specify options such as enabling a safety checker, adjusting random seed for generation stochasticity, and managing output size preset or explicit width/height values.

Compared to previous Bytedance models, Seedream 4.5 expands the number of multi-image references from the earlier v4 architecture while maintaining the same direct, language-driven editing experience. Unlike Seededit v3, which focused solely on image-to-image transformation without generative capabilities, Seedream 4.5 consolidates both image editing and creation into one workflow. In contrast with specialized single-image tools like NAFNet-deblur, Seedream 4.5 is expressly built for more semantically-driven tasks requiring composite assembly and integration of multiple sources based on complex instructions.

Limitations and considerations include the maximum number of reference images (10 per request), output resolution (up to 4 megapixels or 2048x2048), and the total images per batch (no more than 15 across both inputs and outputs). The model maintains spatial and relational consistency in source element integration but is oriented toward visual composition and layout, not general-purpose restoration or enhancement. Best practices recommend leveraging natural language descriptions to achieve precise edibility and referencing needed images in your prompt for optimal results. Seedream 4.5 is licensed for commercial use as part of the fal Partner agreement and is particularly designed to scale efficiently for workflows involving multiple, complex edits in professional environments.