To set video aspect ratios
You can import non-square pixel video, and subsequently preserve the pixel aspect ratio when you encode the video. The Source Dimensions column in the Media Content panel displays the pixel aspect ratio of the source file. If the ratio is 16x9, by choosing the matching aspect ratio in the Video Profile category (Encode panel), you can make sure that your video encodes and displays correctly. Preserving the pixel aspect ratio of the original file ensures a higher-quality encoded video, with a lower transmission bandwidth.
If you want to make sure that the video aspect ratio is appropriate, you can choose Profile Adaptive from the Mode menu. Expression Encoder will automatically set the correct pixel aspect ratio based on the source video aspect ratio.
Non-square pixel content will play back in Microsoft Silverlight but may appear distorted.
To set the video aspect ratio
In the Media Content panel, select the video that you want to adjust.
If you cannot see the Video Profile category on the right side of the application window, on the Window menu, click Encode to open the Encode panel. If Encode is already selected, but the Video Profile category is still not visible, on the right side of the application window, click the Encode tab.
In the Video Profile category, if you do not see the advanced properties underneath the Resize Mode menu, click the Show/Hide advanced properties button .
In the Video Aspect menu, click the video aspect ratio that you want for your encoded video. To change the numeric values, click the number and either type a new value, or drag the value up or right to increase it, or down or left to decrease it. Note the Pixel Aspect value, which changes as you adjust the video aspect. Click Square Pixels to encode each pixel with the same width and height so that the aspect ratio of the output video matches the aspect ratio of the width and height that you specify. This is the default value. Click 4:3 or 16:9 to encode your video in one of those dimensions. Click Source to use the video aspect dimensions of the source file. Click Custom to enter your own video aspect dimensions, located underneath the menu.
If you want the resized video to retain its original aspect ratio, select Maintain Aspect Ratio.