ScreenFlow User Guide
Media Capabilities — Images/Opacity

Images/Opacity

ScreenFlow supports all QuickTime still image formats: TIFF, GIF, JPEG, PNG, etc. Some of these formats (TIFF, GIF, PNG, etc) offer some form of Opacity or Transparency. This is often called an “Alpha” channel and is the preferred method for implementing graphics with semi-transparency, such as logos.

GIF and Transparency

However, in GIF files pixels can only be either fully transparent or fully opaque, they cannot be translucent. Edges can therefore not be smoothly blended with the background, which may cause artefacts in the output video. The solution to this is to obtain the original image (for example, the original Photoshop file), and re-save the image as either TIFF or PNG. Both of these formats support partial transparency.