how to use zimage and flux2 with negative prompt?

[chaowenguo]

Describe the bug

from pipeline_flux_with_cfg import FluxCFGPipeline

it allows to use negative prompt with flux, is there any similar stuff with zimage and flux2?

I means diffusers.ZImagePipeline with Tongyi-MAI/Z-Image-Turbo and diffusers.flux2kleinpipeline with black-forest-labs/FLUX.2-klein-9B I see there is negative_prompt_embeds: str | list[str] | None = None, in the call() function but how to convert negative_prompt to negative_prompt_embeds?

Reproduction

N/A

Logs

System Info

ubuntu22.04-cuda12.4.0-py311-torch2.8.0

Who can help?

@yiyixuxu @DN6

[akshan-main]

For Z-Image, negative_prompt is already supported natively:

pipe("photo of apollo 11", negative_prompt="blurry, low quality", guidance_scale=5.0)

For Flux2 Klein, the call doesn't accept a negative_prompt string directly, but you can pass pre-encoded embeddings via negative_prompt_embeds. To encode a negative prompt:

negative_prompt_embeds, _ = pipe.encode_prompt("blurry, low quality")
image = pipe("photo of apollo11", negative_prompt_embeds=negative_prompt_embeds, guidance_scale=5.0).images[0]