Tips & Tricks

Auctions Live now supports transparent WebM overlays as part of the Scenes Expansion Pack. This guide explains how to create an AI generated green screen video and convert it into a transparent WebM overlay ready to use within your Mult-Lot or In-Room Presentation.

You will learn how to prompt VEO 3 to produce a clean chroma key background and how to use Adobe Premiere Pro with a WebM plugin to remove the green background and export a video file that supports transparency.

This workflow allows subscribers using the Auctions Live Scenes Expansion Pack to design custom animated overlays that appear on top of their Mult-Lot or In-Room auction presentations, providing more control over the visual style of each auction.

Please note that WebM overlays will only function when the Mult-Lot or In-Room Presentation is launched using the latest version of Google Chrome.

This is a general guide only. Software tools, plugins and artificial intelligence platforms evolve quickly and the steps outlined may change over time.

Tools and Software Required

The following tools are required before starting:

• VEO 3 AI Video Generator or similar such as Adobe Firefly
• Adobe Premiere Pro for editing and removing the green background
• Adobe Media Encoder which installs with Premiere Pro
• Fnord WebM Plugin for exporting WebM files with transparency
• Shutter Encoder OpenGL for compressing WebM files

Generating a Green Screen Video in VEO 3

Step 1. Log in to VEO 3 and open the video generation interface.

Step 2. Set the required output resolution and clip length for the overlay.

Step 3. Write a detailed prompt describing the animation. Specify a solid, uniform background using chroma key green colour code #00FF00.

Step 4. Add instructions stating that the subject must not contain green and that no green reflections should appear in the scene.

Step 5. Specify that there must be no shadows, drop shadows, gradients, dark corners or vignette effects.

Step 6. Generate the video and review the result to confirm the background is a perfectly uniform chroma key green.

Step 7. Download the video file as an MP4 once you are satisfied with the result.

Installing the WebM Plugin for Adobe Premiere Pro

Step 1. Open the Adobe Creative Cloud Desktop application.

Step 2. Select Stock and Marketplace and search for WebM.

Step 3. Install the Fnord WebM Plugin so Premiere Pro and Media Encoder can export WebM files with transparency.

Step 4. Restart Premiere Pro to activate the plugin.

Removing the Green Background in Premiere Pro

Step 1. Create a new project and import your VEO 3 video.

Step 2. Drag the clip into a new sequence.

Step 3. In the Effects panel search for Ultra Key and apply it to the clip.

Step 4. In Effect Controls use the eyedropper tool to select the green background.

Step 5. Adjust the key settings to remove all green while keeping the subject intact.

Step 6. Enable the transparency grid in the Program Monitor to confirm that the background has been removed.

To enable the transparency grid in Premiere Pro open the Program Monitor settings using the wrench icon in the bottom right corner. Select Transparency Grid to display the checkerboard pattern which indicates transparent areas.

Exporting a Transparent WebM Overlay

Step 1. Open the Export Settings window by selecting File, Export, then Media.

Step 2. Set the format to WebM.

Step 3. Under Image Settings choose the VP9 codec and enable the option to include the Alpha Channel.

Step 4. Confirm that the resolution and frame rate match the original clip.

Step 5. Choose an output location and select Export or Queue to send the job to Adobe Media Encoder.

Step 6. Test the final WebM file in OBS Studio or a supported browser to confirm transparency works correctly.

Compressing WebM Files

Auctions Live limits the size of assets uploaded within the Scenes Expansion Pack, so you may need to compress the WebM file.

We recommend using Shutter Encoder OpenGL.

Step 1. Download and install the program.

Step 2. Open the application and drag the WebM file into the interface.

Step 3. In the Function field select VP9 from the dropdown menu.

Step 4. On the right side under File Size enter 30MB.

Step 5. In Advanced Features ensure Enable Alpha Channel is selected.

Step 6. Choose the output destination.

Step 7. Click Start Function to compress the file.

Sample VEO 3 Prompt

Subject
Use the provided reference image of the company mascot as the subject. Place the lion in front of a solid, uniform background of chroma key green colour code #00FF00. No other part of the scene may contain green and no green reflections should appear on the lion or surrounding elements.

Lighting
Ensure the background is evenly lit with no shadows, drop shadows, gradients, dark corners or vignette effects. The lion must retain its original appearance, proportions and colours.

Motion
Animate the lion beginning in the distance then running toward the camera. The clip should end with the lion in the foreground delivering a powerful roar directly toward the viewer.

Style
The scene should appear clean, bright and evenly lit with sharp edges. Motion blur should only appear if necessary. The background must remain completely solid green with no variation.