Fix Qwen3-VL normalization: use 0.5/0.5/0.5 from checkpoint#105
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The qwen3-vl VLMSpec hardcoded OpenAI-CLIP normalization stats, but Qwen3-VL checkpoints specify image_mean=image_std=[0.5, 0.5, 0.5]. This caused a silent ~1.86x overscale on every pixel fed to the vision encoder. Fixes apple#82.
stikves
requested review from
alejandro-isaza,
carinapeng,
kevchengcodes and
tjia1818
July 15, 2026 20:55
tjia1818
approved these changes
Jul 15, 2026
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The qwen3-vl VLMSpec hardcoded OpenAI-CLIP normalization stats, but Qwen3-VL checkpoints specify image_mean=image_std=[0.5, 0.5, 0.5]. This caused a silent ~1.86x overscale on every pixel fed to the vision encoder.
Fixes #82.
Tested locally. Now it identifies background colors more correctly.