RealVisXL V5.0 Lightning — 6-bit split Core ML
Self-contained, compiled SDXL package prepared for on-device use by the LocalMuse iOS app. The repository stays private until the artifact manifest and anonymous downloads are verified.
Provenance
- Source UNet:
SG161222/RealVisXL_V5.0_Lightning
- Pinned source revision:
f4454158cedaab9f0688c199561d6c92525f3a85
- Source fp16 UNet LFS SHA-256:
1143cd2aaf65d24af34b5699d090aed724f6c0978c2ec5a5f56821ccb36260ce
- License: CreativeML Open RAIL++-M (
LICENSE.md), inherited from the source model and SDXL base.
The RealVisXL UNet was converted from the pinned source above. The text encoders, VAE encoder/decoder, tokenizer vocabulary, and merges are standard SDXL components reused byte-for-byte from
LocalMuseAI/coreml-dreamshaper-xl-lightning-6bit revision
736408cecf59b3b81a8b2a900cdd5dbf94c34c2a. Only the UNet contains RealVisXL-specific weights.
Conversion
- Apple converter:
apple/ml-stable-diffusion revision e12202c1f6405b83918b58a5d097cd61e3e1f702
- PyTorch
2.4.0
- coremltools
8.0
- Diffusers
0.30.2
- Transformers
4.44.2
- huggingface_hub
0.24.6
- NumPy
1.23.5
- Resolution: fixed
1024 × 1024 (128 × 128 latent)
- Classifier-free-guidance batch:
2
- Attention implementation:
SPLIT_EINSUM
- UNet storage: mixed Float16 and 6-bit palettized weights
- Minimum Core ML deployment target: iOS 17
- UNet split into two independently compiled chunks below 1 GiB each
The source model's fp16 UNet was loaded directly without downloading unrelated full-precision weights, converted through Apple's Stable Diffusion implementation, palettized before chunking, bisected with coremltools, and compiled with xcrun coremlc.
Runtime settings
The source model card recommends 5 inference steps, CFG 1–2, and a DPM++ SDE Karras scheduler. LocalMuse uses:
- Steps:
5
- CFG:
1.5
- Scheduler: second-order DPM-Solver++ multistep
- Timestep spacing: Karras
- Batch size:
1 image (the UNet internally uses batch 2 for CFG)
- UNet: Neural Engine preferred
- VAE: GPU preferred
- Minimum device memory exposed by the app: 8 GiB
Verification
Both chunks compile successfully with Xcode coremlc. Their named input/output feature sets and tensor shapes match the SDXL split-UNet contract already used by LocalMuse. The model is distributed as direct authenticated files; the app pins every URL to a repository commit and verifies the exact SHA-256 and byte count before installation.
Real-device image quality and thermal behavior should still be validated before shipping a production App Store build.
