Local Dream

Android Stable Diffusion with Snapdragon NPU acceleration. Also supports CPU/GPU inference.

Features

• 🎨 txt2img - Generate images from text descriptions
• 🖼? img2img - Transform existing images
• 🎭 inpaint - Redraw selected areas of images
• custom models - Import your own SD1.5 models for CPU (in app) or NPU (follow conversion guide). You can get some pre-converted models from xororz/sd-qnn or Mr-J-369
• lora support - Support adding LoRA weights to custom CPU models when importing.
• prompt weights - Emphasize certain words in prompts. E.g., (masterpiece:1.5). Same format as Automatic1111
• embeddings - Support for custom embeddings like EasyNegative. SafeTensor format is required. Convert pt to safetensors using this
• upscalers - 4x upscaling with realesrgan_x4plus_anime_6b and 4x-UltraSharpV2_Lite

Technical Implementation

NPU Acceleration

• SDK: Qualcomm QNN SDK leveraging Hexagon NPU
• Quantization: W8A16 static quantization for optimal performance
• Resolution: Fixed 512×512 model shape
• Performance: Extremely fast inference speed

CPU/GPU Inference

• Framework: Powered by MNN framework
• Quantization: W8 dynamic quantization
• Resolution: Flexible sizes (128×128, 256×256, 384×384, 512×512)
• Performance: Moderate speed with high compatibility

NPU High Resolution Support

Please note that quantized high-resolution(>768x768) models may produce images with poor layout. We recommend first generating at 512 resolution (optionally you can upscale it), then using the high-resolution model for img2img (which is essentially Highres.fix). The suggested img2img denoise_strength is around 0.8. After that, you can get images with better layout and details.

Device Compatibility

NPU Acceleration Support Compatible with devices featuring:

• Snapdragon 8 Gen 1/8+ Gen 1
• Snapdragon 8 Gen 2
• Snapdragon 8 Gen 3
• Snapdragon 8 Elite
• Snapdragon 8 Elite Gen 5/8 Gen 5
• Non-flagship chips with Hexagon V68 or above (e.g., Snapdragon 7 Gen 1, 8s Gen 3) Note: Other devices cannot download NPU models

CPU/GPU Support

• RAM Requirement: ~2GB available memory
• Compatibility: Most Android devices from recent years

Available Models

The following models are built-in and can be downloaded directly in the app:

Model Type CPU/GPU NPU Clip Skip Source AnythingV5 SD1.5 ? ? 2 CivitAI ChilloutMix SD1.5 ? ? 1 CivitAI Absolute Reality SD1.5 ? ? 2 CivitAI QteaMix SD1.5 ? ? 2 CivitAI CuteYukiMix SD1.5 ? ? 2 CivitAI

🎲 Seed Settings

Custom seed support for reproducible image generation:

• CPU Mode: Seeds guarantee identical results across different devices with same parameters
• GPU Mode: Results may differ from CPU mode and can vary between different devices
• NPU Mode: Seeds ensure consistent results only on devices with identical chipsets