To better control resolution and aspect ratio of output videos, we recommend that
you use the values CopyC#
MaxWidth
CopyC#
MaxHeight
CopyC#
SizingPolicy
CopyC#
PaddingPolicy
CopyC#
DisplayAspectRatio
CopyC#
Resolution
CopyC#
AspectRatio
The display aspect ratio of the video in the output file. Valid values include:
CopyC#
auto
CopyC#
1:1
CopyC#
4:3
CopyC#
3:2
CopyC#
16:9
If you specify CopyC#
auto
If you specify an aspect ratio for the output file that differs from aspect ratio of the input file, Elastic Transcoder adds pillarboxing (black bars on the sides) or letterboxing (black bars on the top and bottom) to maintain the aspect ratio of the active region of the video.

C# |
public string AspectRatio { get; set; }