EPESP0964 User's Guide

AV.io SDI User Guide Preserve aspect ratio (enabled by default)

The Use Input Signal Resolution option allows you to use a video format that is not included on the EDID

or UVCdescriptors. When Use Input Signal Resolution is selected in the AV.io config tool, the input signal

format is added to the UVCdescriptor, which allows a 1:1 capture from the input video source. If the program

you are using is compatible with the signal, you can capture your source in its original format.

For example, if your video resolution was1680×1200, a resolution which is not on the EDID or UVCdescriptor

list, normally you would have to select the closest possible resolution from the provided output descriptor list

in your capture application, and then AV.io SDI would automatically scale the video up or down to that

format. However, if you select the Use Input Signal Resolution option, your capture application's list will

have 1680×1200 as an option for output format.

There are two scenarios in which this feature will not perform as expected.

1. Not all third-party applications are able to support custom resolutions. AV.io SDI will send the custom

resolution to the application, but if it is unable to use the resolution, the application will override any

AV.io SDI custom capture settings.

2. In a Windows environment, due to restrictions set by Microsoft’s Windows Hardware Quality Labs

certification, most graphics adapters or drivers will not output resolutions not included in the EDID file

of the connected display device. In the scenario where a resolution that is not included in the AV.io SDI

standard resolution is requested, the Graphics adapter and driver will apply the resolution requested

and then upscale it to AV.io SDI’s default resolution. This means the Use input signal resolution

feature will not add a custom resolution to the UVCdescriptor and the capture software will be limited

to the pre-defined resolutions.

Outside of these restrictions, the feature is recommended in any scenario where you wish the resolution of

your captured video to be identical to the original video source.

Preserve aspect ratio (enabled by default)

When enabled, your AV.io SDI preserves the aspect ratio of your input signal by adding black bars to the sides

or top and bottom of the frame (only for cases when the application using the signal requests a frame size

with a different aspect ratio). For example,with this option enabled, a 4:3 input signal gets black bars added

to the sides of the image when viewed in an application that requests a 16:9 aspect ratio. With this option

disabled, the 4:3 image is instead stretched to fit the full 16:9 size.

Audio selector for multichannel inputs (disabled by default)

Your AV.io SDI can capture one of the (up to) 8 audio channel pairs provided over SDI. Use this option to allow

your third party application to choose which audio pair to capture. By default, this is disabled and the first

audio pair is captured.