When using SDXL ControlNet (e.g., canny control), the output image size is determined by the explicit width and height parameters in your API request:

The input control signal image will be automatically:

  • Resized to fit your specified dimensions
  • Cropped to preserve aspect ratio

Example: To generate a 768x1344 image, explicitly include these parameters in your request:

{
    "width": 768,
    "height": 1344
}

Note: While these parameters may not appear in the web interface examples, they are supported API parameters that can be included in your requests.