Stability.ai Stable Diffusion 3

The Stable Diffusion 3 models and Stable Image Core model have the following inference parameters and model responses for making inference calls.

Stable Diffusion 3 Large request and response

The request body is passed in the body field of a request to InvokeModel or InvokeModelWithResponseStream.

Model invocation request body field

When you make an InvokeModel call using a Stable Diffusion 3 Large model, fill the body field with a JSON object that looks like the below.

{
    'prompt': 'Create an image of a panda'
}

Model invocation responses body field

When you make an InvokeModel call using a Stable Diffusion 3 Large model, the response looks like the below

{
    'seeds': [2130420379], 
    "finish_reasons": [null], 
    "images": ["..."]
}

A response with a finish reason that is not null, will look like the below:

{
    "finish_reasons": ["Filter reason: prompt"]
}

• seeds – (string) List of seeds used to generate images for the model.

• finish_reasons – Enum indicating whether the request was filtered or not. null will indicate that the request was successful. Current possible values: "Filter reason: prompt", "Filter reason: output image", "Filter reason: input image", "Inference error", null.

• images – A list of generated images in base64 string format.

For more information, see https://platform.stability.ai/docs/api-reference#tag/v1generation.

Text to image

The Stability.ai Stable Diffusion 3 Large model has the following inference parameters for a text-to-image inference call.

• prompt – (string) What you wish to see in the output image. A strong, descriptive prompt that clearly defines elements, colors, and subjects will lead to better results.

  Minimum	Maximum
  0	10,000

Optional fields

• aspect_ratio – (string) Controls the aspect ratio of the generated image. This parameter is only valid for text-to-image requests. Default 1:1. Enum: 16:9, 1:1, 21:9, 2:3, 3:2, 4:5, 5:4, 9:16, 9:21.

• mode – Controls whether this is a text-to-image or image-to-image generation, which affects which parameters are required. Default: text-to-image. Enum: image-to-image, text-to-image.

• output_format – Specifies the format of the output image. Supported formats: JPEG, PNG. Supported dimensions: height 640 to 1,536 px, width 640 to 1,536 px.

• seed – (number) A specific value that is used to guide the 'randomness' of the generation. (Omit this parameter or pass 0 to use a random seed.) Range: 0 to 4294967295.

• negative_prompt – Keywords of what you do not wish to see in the output image. Max: 10.000 characters.

import boto3
import json
import base64
import io
from PIL import Image

bedrock = boto3.client('bedrock-runtime', region_name='us-west-2')
response = bedrock.invoke_model(
    modelId='stability.sd3-large-v1:0',
    body=json.dumps({
        'prompt': 'A car made out of vegetables.'
    })
)
output_body = json.loads(response["body"].read().decode("utf-8"))
base64_output_image = output_body["images"][0]
image_data = base64.b64decode(base64_output_image)
image = Image.open(io.BytesIO(image_data))
image.save("image.png")

Image to image

The Stability.ai Stable Diffusion 3 Large model has the following inference parameters for a image-to-image inference call.

text_prompts (Required) – An array of text prompts to use for generation. Each element is a JSON object that contains a prompt and a weight for the prompt.

• prompt – (string) What you wish to see in the output image. A strong, descriptive prompt that clearly defines elements, colors, and subjects will lead to better results.

  Minimum	Maximum
  0	10,000

• image – String in base64 format. The image to use as the starting point for the generation. Supported formats: JPEG, PNG, WEBP (WEBP not supported in console), Supported dimensions: Width: 640 - 1536 px, Height: 640 - 1536 px.

• strength – Numerical. Sometimes referred to as denoising, this parameter controls how much influence the image parameter has on the generated image. A value of 0 would yield an image that is identical to the input. A value of 1 would be as if you passed in no image at all. Range: [0, 1]

• mode – must be set to image-to-image.

Optional fields

• aspect_ratio – (string) Controls the aspect ratio of the generated image. This parameter is only valid for text-to-image requests. Default 1:1. Enum: 16:9, 1:1, 21:9, 2:3, 3:2, 4:5, 5:4, 9:16, 9:21.

• mode – Controls whether this is a text-to-image or image-to-image generation, which affects which parameters are required. Default: text-to-image. Enum: image-to-image, text-to-image.

• output_format – Specifies the format of the output image. Supported formats: JPEG, PNG. Supported dimensions: height 640 to 1,536 px, width 640 to 1,536 px.

• seed – (number) A specific value that is used to guide the 'randomness' of the generation. (Omit this parameter or pass 0 to use a random seed.) Range: 0 to 4294967295.

• negative_prompt – Keywords of what you do not wish to see in the output image. Max: 10.000 characters.

import boto3
import json
import base64
import io
from PIL import Image

bedrock = boto3.client('bedrock-runtime', region_name='us-west-2')
file_path = 'input_image.png'
image_bytes = open(file_path, "rb").read()
base64_image = base64.b64encode(image_bytes).decode("utf-8")
response = bedrock.invoke_model(
    modelId='stability.sd3-large-v1:0',
    body=json.dumps({
        'prompt': 'A car made out of fruits',
        'image': base64_image,
        'strength': 0.75,
        'mode': 'image-to-image'
    })
)
output_body = json.loads(response["body"].read().decode("utf-8"))
base64_output_image = output_body["images"][0]
image_data = base64.b64decode(base64_output_image)
image = Image.open(io.BytesIO(image_data))
image.save("output_image.png")