Image transformation

The following image transformations can be applied:

Aspect ratio

To change the aspect ratio of the image use the menus under Image ‣ Image format.

Some devices use non-rectangular pixels and don’t fill the corresponding pixel aspect ratio value in the file metadata. In these case it might be necessary to force the aspect ratio to a known value.

The following options are available:

  • Auto detection

  • Force 4:3

  • Force 16:9

Rotation

To change the orientation of the image use the menus under Image ‣ Image rotation.

The following options are available:

  • No rotation

  • 90° clockwise

  • 90° counter-clockwise

  • 180°

Videos filmed in portrait mode on a smartphone typically already have a flag embedded in the video file and don’t need to be manually rotated.

Mirroring

To flip the image horizontally use the menu Image ‣ Mirror.

Deinterlacing

To deinterlace the video use the menu Image ‣ Deinterlace.

Some capture devices store video using an interlaced format. Interlaced videos store half images at twice the frame rate, alternating odd and even rows. This causes a combing artifact when the filmed motion is fast as objects or subjects move during the half frame interval.

The deinterlacing algorithm reconstructs full images by combining rows from adjacent frames.

../_images/deinterlacing.png

Demosaicing

Videos saved in Bayer mode contain the raw sensor data before color reconstruction. The color can be rebuilt using the menu under Image ‣ Demosaicing.

../_images/debayering.png

The following options are available:

  • RGGB

  • BGGR

  • GRBG

  • GBRG

The appropriate option to select depends on the device and mode used during recording.

Stabilization

To stabilize the image by a previously tracked object, use the menu Image ‣ Stabilization and select a track.

The tracked object will be kept at the same position in the image, stabilizing the video around it.

This is a simple 2D stabilization suitable for small camera shake or to “lock in” on an object or body part. If the camera is undergoing a rotation or zoom, consider using the Camera motion estimation function.

Zoom & magnification

To zoom into the image use CTRL + mouse wheel or CTRL + Minus and CTRL + Plus.

CTRL + Numpad0 resets the zoom level.

The magnifier tool can also be used to create a picture in picture magnified area.

../_images/magnifier1.png