WaveSpeedAI APIFlux Dev LoRA Ultra Fast

Flux Dev Lora Ultra Fast

Rapid, high-quality image generation with FLUX.1 [dev] and LoRA support for personalized styles and brand-specific outputs, ultra fast !

Features

The Flux-Dev-LoRA-Ultra-Fast model is a collection of fine-tuned models , specifically designed for text-to-image generation. LoRA, which stands for Low-Rank Adaptation, is a technique used to fine-tune pre-trained models efficiently. The Flux-Dev-Lora-ultra-fast model is based on the FLUX.1-dev model by Black Forest Labs.This model combines the personalization capabilities of wavespeed-ai with ultra-fast image generation, delivering high-quality outputs in under 2 seconds.

Key Features

  • Ultra-Fast Generation: Delivers high-quality images from text prompts in under 2 seconds.
  • LoRA Fine-Tuning Support: Enables personalized styles and brand-specific outputs through LoRA fine-tuning.
  • Specialized Style LoRAs: Includes various specialized LoRAs for different styles and themes, such as:
    • Total Drama Character LoRA: Generates images of cartoon geometric simplified portraits in the style of the Total Drama series.
    • Yarn Art LoRA: Generates images in a yarn art style.
  • Open Weights: Provides open access to model weights, facilitating scientific research and creative development.
  • Versatile Usage: Suitable for personal, scientific, and commercial applications, offering flexibility across various use cases.

ComfyUI

flux-dev-lora-ultra-fast is also available on ComfyUI, providing local inference capabilities through a node-based workflow, ensuring flexible and efficient image generation on your system.

Limitations

  • Creative Focus: Designed primarily for creative image synthesis; not intended for generating factually accurate content.
  • Inherent Biases: Outputs may reflect biases present in the training data.
  • Input Sensitivity: The quality and consistency of generated images depend significantly on the quality of the input text; subtle variations may lead to output variability.​
  • Prompt Dependency: The model's performance is closely tied to the clarity and structure of the prompts; careful crafting may be necessary for optimal results.

Out-of-Scope Use

The model and its derivatives may not be used in any way that violates applicable national, federal, state, local, or international law or regulation, including but not limited to:

  • Exploiting, harming, or attempting to exploit or harm minors, including solicitation, creation, acquisition, or dissemination of child exploitative content.
  • Generating or disseminating verifiably false information with the intent to harm others.
  • Creating or distributing personal identifiable information that could be used to harm an individual.
  • Harassing, abusing, threatening, stalking, or bullying individuals or groups.
  • Producing non-consensual nudity or illegal pornographic content.
  • Making fully automated decisions that adversely affect an individual’s legal rights or create binding obligations.
  • Facilitating large-scale disinformation campaigns.

Accelerated Inference

Our accelerated inference approach leverages advanced optimization technology from WavespeedAI. This innovative fusion technique significantly reduces computational overhead and latency, enabling rapid image generation without compromising quality. The entire system is designed to efficiently handle large-scale inference tasks while ensuring that real-time applications achieve an optimal balance between speed and accuracy. For further details, please refer to the blog post.

Authentication

For authentication details, please refer to the Authentication Guide.

API Endpoints

Submit Task & Query Result


# Submit the task
curl --location --request POST "https://api.wavespeed.ai/api/v2/wavespeed-ai/flux-dev-lora-ultra-fast" \
--header "Content-Type: application/json" \
--header "Authorization: Bearer ${WAVESPEED_API_KEY}" \
--data-raw '{
    "prompt": "geometric tall character design, in the style of TTLDRMCHR. Donald Trump and a mexican skeleton, vibrant color background",
    "image": "",
    "strength": 0.8,
    "loras": [
        {
            "path": "linoyts/yarn_art_Flux_LoRA",
            "scale": 1
        }
    ],
    "size": "1024*1024",
    "num_inference_steps": 28,
    "guidance_scale": 3.5,
    "num_images": 1,
    "seed": -1,
    "enable_base64_output": true,
    "enable_safety_checker": true
}'

# Get the result
curl --location --request GET "https://api.wavespeed.ai/api/v2/predictions/${requestId}/result" \
--header "Authorization: Bearer ${WAVESPEED_API_KEY}"

Parameters

Task Submission Parameters

Request Parameters

ParameterTypeRequiredDefaultRangeDescription
promptstringYesgeometric tall character design, in the style of TTLDRMCHR. Donald Trump and a mexican skeleton, vibrant color background-Input prompt for image generation
imagestringNo--
mask_imagestringNo--The mask image tells the model where to generate new pixels (white) and where to preserve the original image (black). It acts as a stencil or guide for targeted image editing.
strengthnumberNo0.80.01 ~ 1.00Strength indicates extent to transform the reference image
lorasarrayNo[]max 5 itemsList of LoRAs to apply (max 5)
loras[].pathstringYes-Path to the LoRA model
loras[].scalefloatYes-0.0 ~ 4.0Scale of the LoRA model
sizestringNo1024*1024512 ~ 1536 per dimensionOutput image size
num_inference_stepsintegerNo281 ~ 50Number of inference steps
guidance_scalenumberNo3.50.0 ~ 10.0Guidance scale for generation
num_imagesintegerNo11 ~ 4Number of images to generate
seedintegerNo-1-1 ~ 9999999999Random seed (-1 for random)
enable_base64_outputbooleanNotrue-If enabled, the output will be encoded into a BASE64 string instead of a URL.
enable_safety_checkerbooleanNotrue-Enable safety checker

Response Parameters

ParameterTypeDescription
codeintegerHTTP status code (e.g., 200 for success)
messagestringStatus message (e.g., “success”)
data.idstringUnique identifier for the prediction, Task Id
data.modelstringModel ID used for the prediction
data.outputsarrayArray of URLs to the generated content (empty when status is not completed)
data.urlsobjectObject containing related API endpoints
data.urls.getstringURL to retrieve the prediction result
data.has_nsfw_contentsarrayArray of boolean values indicating NSFW detection for each output
data.statusstringStatus of the task: created, processing, completed, or failed
data.created_atstringISO timestamp of when the request was created (e.g., “2023-04-01T12:34:56.789Z”)
data.errorstringError message (empty if no error occurred)
data.timingsobjectObject containing timing details
data.timings.inferenceintegerInference time in milliseconds

Result Query Parameters

Result Request Parameters

ParameterTypeRequiredDefaultDescription
idstringYes-Task ID

Result Response Parameters

ParameterTypeDescription
codeintegerHTTP status code (e.g., 200 for success)
messagestringStatus message (e.g., “success”)
dataobjectThe prediction data object containing all details
data.idstringUnique identifier for the prediction
data.modelstringModel ID used for the prediction
data.outputsarrayArray of URLs to the generated content (empty when status is not completed)
data.urlsobjectObject containing related API endpoints
data.urls.getstringURL to retrieve the prediction result
data.has_nsfw_contentsarrayArray of boolean values indicating NSFW detection for each output
data.statusstringStatus of the task: created, processing, completed, or failed
data.created_atstringISO timestamp of when the request was created (e.g., “2023-04-01T12:34:56.789Z”)
data.errorstringError message (empty if no error occurred)
data.timingsobjectObject containing timing details
data.timings.inferenceintegerInference time in milliseconds
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