Video input synchronisation

Preamble

The rendering service of Smode runs into a different thread than the devices. For each input devices, a new thread is created. A main point to know is that the phase of calculation of both threads might differs, for better or worse. Let's visualize each thread as a sinusoidal as follows:
In a perfect theoretical world, both thread should look like this: But 2 problems are regularly encountered when capturing a signal:
Drift : signal offset in time. It looks like a badly set clock, for example to a hundredth of a second. After several months, this clock will indicate the wrong time. The same applies to a signal. After a few hours, the required frame will not be transmitted, creating frame drops.
Jitters : The transmission phase Oscillates. In other words, the frequency is not constant from one frame to the next.
By default, a Genlocked signal seeks to produce a signal without Drift, but do not provide anything against the Jitters issue.
In Smode, to avoid jitters issues, the phase of the video input thread is on purpose delayed by 1/2 frames. So a Genlocked and smooth signal should look like this:

Automatic synchronisation

By default, SMODE is automatically able calculate the delay to apply to the video input threads in order to get the frame correctly at the new rendering cycle. You can have a idea by going on the Auto syncher The synchronization settings for Video Input Device Read More /Syncher/Delay option of each Video Input Device Video Input Devices are used to capture video streams in Smode Read More