The Video Sequencer preview is used to display the rendering result from the Video Sequencer’s timeline. This can be further configured to display the output from a certain channel, overlay, or image analyzer (scope).
You can adjust the view by zooming in with NumpadPlus and zoom out with NumpadMinus. Pressing Home at anytime resets the zoom to maximize the size of the preview within the editor’s area.
The Preview contains two regions (see figure 1), the Header is shown in a yellow outline with the Preview (red outline) underneath. This Preview has no fixed dimensions; you can zoom in or move indefinitely. However, in figure 1 you see a checkered area (green outline). This preview has the aspect ratio of the Project Dimensions; e.g. 1920 x 1080 pixels in figure 1. But, because the source strip could be scaled or a different resolution, the yellow outline shows the area that the source strip occupies. As you can see, the source video has a different resolution than the project and letterboxes are added at the top and bottom of the image.
In contrast to the Sequencer View example, both the Toolbar and Sidebar are expanded in figure 1. The gizmos however are unique for the Preview.
You can use gizmos to move and scale the image in the Video Sequencer preview region.
See Gizmos to manage the visibility of gizmos.