# Adjust the video aspect ratio

Aim

To correct for image distortion that sometimes occurs when recording video from analog cameras.

Prerequisites

▪You track from pre-recorded video files.

▪You know that the aspect ratio in the video file differs from that of the original camera image.See Check the video aspect ratio

Procedure

1.Open the Area Settings.

2.Click the Adjust Aspect Ratio button.

3.Choose the option based on the software and hardware you used (see below), then click OK.

Options

If you used Noldus MPEG Recorder 1.1/2.0, or MediaRecorder, and analog cameras

▪When you used MediaRecorder with a Picolo H.264 encoder board, choose Noldus Recorder and select Euresys PICOLO U4 H.264. Make sure you select the TV standard of the camera (NTSC or PAL).

▪When you used an older encoder board (Picolo Diligent or IVC-4300), choose Noldus Recorder and select one of the other options.

If you used MediaRecorder, and digital cameras

▪In most cases you do not need to correct the aspect ratio. However, if you are sure the video image is distorted, select Custom and enter the correct aspect ratio.

If you used video files recorded with EthoVision XT, but in a different experiment

▪Select Noldus Recorder and select Euresys Picolo U4 H.264.

If you used video files recorded with programs other than MediaRecorder:

▪Select Custom and enter the adjusted aspect ratio. See Calculate the correct aspect ratio in a video image