Alpha channel support, Sending video and audio from vmix using ndi – vMix Live Production Software Pro User Manual
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See
for more information.
Sending video and audio from vMix using NDI
vMix supports sending a number of different types of output via NDI.
To enable a particular type of output for NDI, it must first be turned on from
Output 1
This is the main Output (or "Program") feed and includes the Master stereo audio mix
Output 2, 3, 4
These are independent outputs that can be configured to show Output, Preview, MultiView or a particular
input.
See
Cameras / Calls / Audio Inputs
Any Camera, Video Call or Audio inputs currently being used in vMix can also be viewed remotely via NDI.
Audio Outputs
Master, Headphones, A and B mixes in vMix can all be independently accessed over the network using NDI.
The A and B mixes can be enabled by assigning them to Enabled in the dropdown list in
and also by checking the Audio Output box in the NDI section under
Changing additional settings such as audio channel on an Output
Output 1,2,3 and 4 each have a cog button that provides access to additional options when using these
outputs with NDI, SRT, MultiCorder or with Instant Replay.
(Note; vMix Call has a separate option to select an audio track for a caller, so in this case, changing the
audio source here will have no effect).
The two options currently available allow sending a particular audio bus, or enabling alpha channel support.
Alpha Channel Support
Alpha Channel Support for NDI Sources
vMix automatically supports alpha channel when it is detected on an NDI source.
If the source provides the video as "pre-multiplied alpha", be sure to turn on the checkbox in the
Colour
Adjust
tab in
Input Settings
Alpha Channel Support for NDI Output
When using the Output options with NDI, these will by default send standard "YUV" video without alpha
channel.
To enable Alpha Channel on output follow the steps below:
1. Open vMix Settings and go to the Outputs / NDI tab
2. Click the cog icon next to the Output you wish to enable Alpha Channel for.
3. Under the Alpha Channel setting, select Straight or Premultiplied depending on the receiving application
requirements.