AV.io SDI User Guide
Preserve aspect rat io (enabled by def ault )
The Use Input Signal Resolut ion opt ion allows you t o use a video f ormat t hat is not included on t he EDID
or UVC descript ors. When Use Input Signal Resolut ion is select ed in t he AV.io conf ig t ool, t he input signal
f ormat is added t o t he UVC descript or, which allows a 1:1 capt ure f rom t he input video source. If t he program
you are using is compat ible wit h t he signal, you can capt ure your source in it s original f ormat .
For example, if your video resolut ion was 1680×1200, a resolut ion which is not on t he EDID or UVC descript or
list , normally you would have t o select t he closest possible resolut ion f rom t he provided out put descript or list
in your capt ure applicat ion, and t hen AV.io SDI would aut omat ically scale t he video up or down t o t hat
f ormat . However, if you select t he Use Input Signal Resolut ion opt ion, your capt ure applicat ion's list will
have 1680×1200 as an opt ion f or out put f ormat .
There are t wo scenarios in which t his f eat ure will not perf orm as expect ed.
1. Not all t hird-part y applicat ions are able t o support cust om resolut ions. AV.io SDI will send t he cust om
resolut ion t o t he applicat ion, but if it is unable t o use t he resolut ion, t he applicat ion will override any
AV.io SDI cust om capt ure set t ings.
2. In a Windows environment , due t o rest rict ions set by Microsof t ’s Windows Hardware Qualit y Labs
cert if icat ion, most graphics adapt ers or drivers will not out put resolut ions not included in t he EDID f ile
of t he connect ed display device. In t he scenario where a resolut ion t hat is not included in t he AV.io SDI
st andard resolut ion is request ed, t he Graphics adapt er and driver will apply t he resolut ion request ed
and t hen upscale it t o AV.io SDI’s def ault resolut ion. This means t he Use input signal resolut ion
f eat ure will not add a cust om resolut ion t o t he UVC descript or and t he capt ure sof t ware will be limit ed
t o t he pre-def ined resolut ions.
Out side of t hese rest rict ions, t he f eat ure is recommended in any scenario where you wish t he resolut ion of
your capt ured video t o be ident ical t o t he original video source.
Preserve aspect rat io (enabled by default )
When enabled, your AV.io SDI preserves t he aspect rat io of your input signal by adding black bars t o t he sides
or t op and bot t om of t he f rame (only f or cases when t he applicat ion using t he signal request s a f rame size
wit h a dif f erent aspect rat io). For example, wit h t his opt ion enabled, a 4:3 input signal get s black bars added
t o t he sides of t he image when viewed in an applicat ion t hat request s a 16:9 aspect rat io. Wit h t his opt ion
disabled, t he 4:3 image is inst ead st ret ched t o f it t he f ull 16:9 size.
Audio select or for m ult ichannel input s (disabled by default )
Your AV.io SDI can capt ure one of t he (up t o) 8 audio channel pairs provided over SDI. Use t his opt ion t o allow
your t hird part y applicat ion t o choose which audio pair t o capt ure. By def ault , t his is disabled and t he f irst
audio pair is capt ured.
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