MOAMaster
commented
2 years ago I think I see what is missing. I went into the Steinburg spec. Here is what I found:
tresult PLUGIN_API PlugProcessor::process (Vst::ProcessData& data) { // first they read any parameter changes used for processing the audio, then --
if (data.numInputs == 0 || data.numSamples == 0) return kResultOk; }
So, the host is sending these two fields to allow you to skip processing if no real data is passed.
Your wrapper called AudioIOPort needs to forward these two key values to the plugin so we can avoid any real processing.
Looking at the length of the input buffers does not work. I checked. An empty buffer is being sent, in my case with 980 or so items.
I think that having these kind of guards is critical to reliable performance. My algorithm is blowing up because it's trying to execute on empty arrays.
I'll try coding in an exception handler, that might solve the problem. But would really like to follow the spec.
Thanks.
Bruce
It looks like the host is sending these two fields in
mikeoliphant
I am a bit confused about how the host and the plugin interact.
How can a plug-in detect that real data is coming through because the operator has pushed the start button?
From what I can tell using message boxes, when the operator loads the plug in into the host, a series of function calls are made to the plugin which include Initialize, InitializeProcessing, and Start. Then, regular calls to Process are made -- even though the user has not clicked on play in the host.
I have an algorithm that I only want to run in the presence of actual data. If this algorithm runs without real data, then the algorithm crashes the application.
I tried checking if the inputSamples.Length is > 0. Well, that value is greater than zero although there is no real data to process.
So, how do I detect that there is real data in the input buffer? I thought that Start or InitializeProcessing would be called just after the operator clicked on Play or that no Process calls would be made if the operator had not clicked on Play. But, apparently, all of those are invoked at the time the plugin is loaded.
So, How can a plug-in detect that real data is coming through because the operator has pushed the start button? Any ideas?
You can't check for all zeros in the input buffer because that would also indicate silence.
Thanks.
Bruce