Using Sketches and Reference Images

This guide covers how to use a sketch to influence your generation at various levels of strength and how to use a reference image to influence style of the output image.

Using a Sketch

1. Upload Your Sketch: Start by uploading the image containing your sketch into the Invoke application. Select a board, drag your image into the app, and find the image in your “Assets” tab. You can use your own sketch or follow along with the image below.
2. Add Control Layer: Add your sketch image as a control layer - You can do this easily by dragging the sketch into the canvas. The Control Layer will guide the generation process.
3. Choose Control Mode: Select the 'Contour Detection (Scribble)' mode then filter your image. This will convert the sketch into a format usable by the Control Layer.
4. Clean Up the Sketch: You can modify the sketch, erasing or adding content to refine the sketch, removing any errant lines or imperfections. Focus on the outlines and contours of the shapes or structures you want to generate.
5. Generate the Image: Click the 'Invoke' button to create your image based on the sketch. The Weight & End Step will have a significant impact on how much freedom the AI will have to add additional details and change the image. The below images show a few settings with the above sketch:

Example output:

High Precision Control

Weight: 1

End Step - 100%

Moderate Precision Control

Weight: .75

End Step - 75%

Basic Compositional Control

Weight: .5

End Step - 50%

Using a Reference Image

If we want to better control our generation, we can use a Reference Image to help inspire the color and style of the image.

1. Global Reference Image:
   • A Global Reference Image applies to the entire image. You can add your reference image to apply its style to the entire generation. This option influences the overall look of the generated image.
   • Drag a reference image into the canvas from your Gallery/Assets - You can use this image if you’d like to follow along    
   • For this example, you might only want to loosely guide some of the core colors/aesthetics, so you can set the settings to one of the “Standard Reference” options, with the Method “Style”, and a Weight of .5Example output:
2. Regional Reference Image:
   • In the above example, you might like some aspects of this (the armor) but don’t love that it directly influenced the background of the image and his skin. You can change your mind here by adding a Regional Reference Image layer.
   • You can drag the image from the Global Reference Image into this new layer using the same settings.
   • Then delete the old Global Reference Image layer.
   • Using the brush tool, with the Regional Reference Image layer selected, you will select the areas of the generation that this image should apply to.
   • To help control the influence of the background, you are going to add a Regional Guidance layer, with the prompt “White Background”, to help control.