o i@sddlZddlmZddlmZddlmZmZGdddejZ dej de d e d ej fd d Z Gd ddejZ GdddeZd efddZdS)N)override)sigma_to_half_log_snr)ComfyExtensionioc@s0eZdZdZeddZedejfddZdS)EpsilonScalinga Implements the Epsilon Scaling method from 'Elucidating the Exposure Bias in Diffusion Models' (https://arxiv.org/abs/2308.15321v6). This method mitigates exposure bias by scaling the predicted noise during sampling, which can significantly improve sample quality. This implementation uses the "uniform schedule" recommended by the paper for its practicality and effectiveness. c Cs@tjddtjdtjjdddddtjjd d gtjgd S) NzEpsilon Scalingmodel_patches/unetmodelscaling_factorgGz?g?g?MbP?T)defaultminmaxstep display_modeadvanced)node_idcategoryinputsoutputsrSchemaModelInputFloat NumberDisplaynumberOutputclsr4/mnt/c/Users/fbmor/ComfyUI/comfy_extras/nodes_eps.py define_schemas"  zEpsilonScaling.define_schemareturncs4dkrdfdd}|}||t|S)Nrg& .>cs,|d}|d}||}|}||}|S)z This function is applied after the CFG guidance has been calculated. It recalculates the denoised latent by scaling the predicted noise. denoisedinputr)argsr#x noise_predscaled_noise_pred new_denoisedr rr epsilon_scaling_function-s z8EpsilonScaling.execute..epsilon_scaling_functionclone#set_model_sampler_post_cfg_functionr NodeOutput)rrr r+ model_clonerr*r execute's    zEpsilonScaling.executeN) __name__ __module__ __qualname____doc__ classmethodr!rr/r1rrrr rs  rsnrtsr_k tsr_variancer"cCs4t|}||d|||d}t|||S)zCompute the rescaling score ratio in Temporal Score Rescaling. See equation (6) in https://arxiv.org/pdf/2510.01184v1. )torchisposinfwhere)r7r8r9 posinf_maskrescaling_factorrrr compute_tsr_rescaling_factorEs r@c@s,eZdZeddZedejfddZdS)TemporalScoreRescalingcCshtjdddtjdtjjddddd d tjjd d tjjd dddd d tjjd d gtjjddgddS)NrAzTSR - Temporal Score Rescalingrrr8zControls the rescaling strength. Lower k produces more detailed results; higher k produces smoother results in image generation. Setting k = 1 disables rescaling.gffffff?g{Gz?gY@r T)tooltipr r r rrr tsr_sigmazMControls how early rescaling takes effect. Larger values take effect earlier.g? patched_model) display_namez[Post-CFG Function] TSR - Temporal Score Rescaling (2510.01184) Rescaling the model's score or noise to steer the sampling diversity. )rrErrr descriptionrrrrr r!Rs@  z$TemporalScoreRescaling.define_schemar"cs2|dfdd}|}||t|S)Nc s|d}|d}|d}|d}dks|dkr|S|jd}t||}d|}|dkr1|St|}||} t|| ||S) Nr#r$sigmarr:rmodel_samplingrG)current_patcherget_model_objectrexpr@r;lerp) r%r#r&rH curr_modelrI half_log_snrr7 rescaling_ralphar8r9rr temporal_score_rescalings     z@TemporalScoreRescaling.execute..temporal_score_rescalingr,)rrr8rCrSmrrRr r1s   zTemporalScoreRescaling.executeN)r2r3r4r6r!rr/r1rrrr rAQs  .rAc@s(eZdZedeeejfddZdS)EpsilonScalingExtensionr"cs ttgSN)rrA)selfrrr get_node_listsz%EpsilonScalingExtension.get_node_listN) r2r3r4rlisttyper ComfyNoderXrrrr rUsrUcstSrV)rUrrrr comfy_entrypointsr\)r;typing_extensionsrcomfy.k_diffusion.samplingrcomfy_api.latestrrr[rTensorfloatr@rArUr\rrrr s"  =  Q