Files
2026-06-07 20:43:31 -07:00

1.9 KiB

OmniGen2

OmniGen2 is a multimodal generation model with dual decoding pathways for text and image, built on the Qwen-VL-2.5 foundation by VectorSpaceLab.

Model Variants

OmniGen2

  • 3B vision-language encoder (Qwen-VL-2.5) + 4B image decoder
  • Dual decoding with unshared parameters for text and image
  • Decoupled image tokenizer
  • Apache 2.0 license

OmniGen v1

  • Earlier single-pathway architecture
  • Fewer capabilities than OmniGen2
  • Superseded by OmniGen2

Key Features

  • Text-to-image generation with high fidelity and aesthetics
  • Instruction-guided image editing (state-of-the-art among open-source models)
  • In-context generation combining multiple reference inputs (humans, objects, scenes)
  • Visual understanding inherited from Qwen-VL-2.5
  • CPU offload support reduces VRAM usage by nearly 50%
  • Sequential CPU offload available for under 3GB VRAM (slower inference)
  • Supports negative prompts and configurable guidance scales

Hardware Requirements

  • Minimum: NVIDIA RTX 3090 or equivalent (~17GB VRAM)
  • With CPU offload: ~9GB VRAM
  • With sequential CPU offload: under 3GB VRAM (significantly slower)
  • Flash Attention optional but recommended for best performance
  • CUDA 12.4+ recommended
  • Default output resolution: 1024x1024

Common Use Cases

  • Text-to-image generation
  • Instruction-based photo editing
  • Subject-driven image generation from reference photos
  • Multi-image composition and in-context editing

Key Parameters

  • text_guidance_scale: Controls adherence to text prompt (CFG)
  • image_guidance_scale: Controls similarity to reference image (1.2-2.0 for editing, 2.5-3.0 for in-context)
  • num_inference_step: Diffusion steps (default 50)
  • max_pixels: Maximum total pixel count for input images (default 1024x1024)
  • negative_prompt: Text describing undesired qualities (e.g., "blurry, low quality, watermark")
  • scheduler: ODE solver choice (euler or dpmsolver++)