SimpleTuner/ltxvideo-2.3-convrot-int8

LTX-Video 2.3 distilled — INT8 ConvRot

This repository contains a transformer-only INT8 ConvRot quantization of the official Lightricks/LTX-2.3 distilled checkpoint. It is derived directly from ltx-2.3-22b-distilled.safetensors; no fine-tune, task adapter, or third-party model weights were merged.

Artifact

• File: ltx-2.3-convrot-int8.safetensors
• Size: 19,485,049,192 bytes
• SHA-256: 722e2498f59306aa007f25560d6069f621ae57c90705cdaa0e2de4a1db996d05
• Source SHA-256: 14409a4d1337a8ded02fa87fb895b17a91ab2c6588f7cc3352e624ff18a689bf

The file contains the main audiovisual transformer only. Load the text encoder, connectors, VAE, audio VAE, and vocoder from the official LTX 2.3 Diffusers pipeline. Weights use Comfy-style per-layer int8_tensorwise sidecars and are consumed by an SDNQ Hadamard/ConvRot loader.

Quantization

The checkpoint was quantized on an NVIDIA H200 with Comfy-Org/comfy-model-tools commit 1fe341bb8a4e46f161a978b5faa2412d8c39c768:

python quant_int8_convrot.py   ltx-2.3-22b-distilled.safetensors   ltx-2.3-22b-distilled-int8-convrot.safetensors   --mseclip   --verify-report quantization-report.tsv

The packaging step retained model.diffusion_model.* tensors and omitted the bundled connector copies, since the target Diffusers pipeline supplies its connector components separately.

• ConvRot group size: 256
• Quantized transformer linears: 1,344
• Mean relative weight reconstruction error: 0.859%
• Maximum relative weight reconstruction error: 1.446%
• Worst per-layer cosine similarity: above 0.99990

The full per-layer measurements are in quantization-report.tsv.

Validation

The artifact was loaded with SDNQ 0.2.3 into LTX2VideoTransformer3DModel with all 1,344 quantized parameters wrapped and no remaining meta tensors. A real audiovisual transformer forward at 768×512, 121 frames, and 1,024 text tokens produced finite video and audio outputs. On the calibration H200, three warmed steps averaged 0.5493 seconds with 19.139 GiB peak allocated memory. These are transformer-only measurements, not end-to-end generation timings.

License

This is a derivative of LTX-2.3 and remains subject to the LTX-2 Community License Agreement. Review that agreement, including its commercial-use and acceptable-use restrictions, before using or redistributing the checkpoint.