In OnTheAir Video 3 and OnTheAir Video Express 3, there is a ""Log" window. You can open this window by going to the menu "Window > Show Log Window", or it will popup automatically if any important issue is happening to your playout.
At the top of the window are 6 different gauges that can help you understand how your computer is performing.
What does it mean when the gauge is empty or when it is full/red
The first 4 gauges (Reading, Decompression, Rendering, Output) work the same way:
1. The gauge is full = It took more than the duration of one frame to process the operation => there will be some drop frames on the output.
2. The gauge is red but not full = it took more than 85% of the duration of one frame to process the operation => there will not be any drop frames, but you are getting very close to the limit.
3. The gauge is orange = it took more than 70% of the duration of one frame to process the operation => there will not be any drop frames, but you should monitor that.
4. The gauge is green = it took less than 70% of the duration of one frame to process the operation.
The last 2 gauges are not related to a time it takes to process an operation but rather to how full the system memory and the buffers are.
But anyway, if you have to remember one thing, remember that the emptier the gauge is, the better !
Note that for all gauges, there is a peak so you can know what was the maximum value that was reached. You can reset the peak by clicking on the gauge. The duration of the frame is calculated using the output fps, not the file fps.
What do each gauge mean?
Each Gauge has a specific meaning and they follow one another in a given order. You read your frames from the disk before you decompress, then you render them, and then you output them. This means that a drop of performance in one of the earlier gauge can impact the others.
- Reading = shows the read performances from the disk. If the gauge is red and full, it means that we can not read at sufficient speed from your disk as it takes more than the duration of one frame to read from the disk.
- Decom. = the decompression of the file. This is done on the processor of your computer and will depend on 3 things: your CPU, the codec and format of the file that you decompress. The better your CPU, the better these performances. Also decompressing frames in H264 is much more intensive than decompressing ProRes frames.
- Rendering = this is the time it takes to render the frames. This task is mainly done in the GPU so the better the graphic card, the better these performances. Also note that the graphic card is much more used when the "Smart Resize and Graphics" option of OnTheAir Video is enabled, and thus if you experience some performance issues there, you may want to disable this option. Also you can try to quit any other application that could use the Graphic card.
- Output = this is how long it takes to transfer the rendered frame to the card.
- Sys. memory = this gauge is not related at all to the time it takes to process anything, but only shows the percentage of memory used by the computer (not for the application only, it's the global memory usage)
- Buffers = how full the buffers are. If this fill up it means that there is an issue in at least one of the operation that takes too long.