Fix wrong do_classifier_free_guidance threshold in ZImagePipeline#13183
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kirillsst wants to merge 1 commit intohuggingface:mainfrom
Open
Fix wrong do_classifier_free_guidance threshold in ZImagePipeline#13183kirillsst wants to merge 1 commit intohuggingface:mainfrom
do_classifier_free_guidance threshold in ZImagePipeline#13183kirillsst wants to merge 1 commit intohuggingface:mainfrom
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Z-Image uses CFG formula `pred = pos + scale * (pos - neg)` where `guidance_scale = 0` means no guidance. The threshold should be `> 0` instead of `> 1` to match this formula.
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Summary
pred = pos + guidance_scale * (pos - neg), whereguidance_scale = 0corresponds to no guidancedo_classifier_free_guidanceproperty was checking> 1(standard diffusers convention), but for this formula it should be> 0guidance_scalevalues between 0 and 1 (e.g. 0.5) to be silently ignoredFixes #12905