VidCap - Stop All / Start This

[SoundRehabAustria]

Hi Eric

Would you be so kind to explain why "Stop All / Start This" of the VidCap module is only meant for debugging and not accessible via MIDI control? Would it be possible to make these 2 buttons controlable via MIDI events in future releases?

The reason I ask: I got 2 webcams running fine if plugged into different USB controlles. Any additional webcam shows up in the Vid Cap module, but only 2 at a time seem to work. Using "Stop All / Start This" functionality I could change between video feeds and 2 feeds at a time would be OK if could stop and start cameras automated in the performane.

Alternatively, using some sort of external batch command to stop / start cams would also do. Maybe you could expose the windows functionality you are calling and let me know if there is a way call the same functions e.g. via cmd scripts, python, etc.

Many thanks in advance.

Robert

Stop All:
Stop all capture devices that are running. For debugging only; not for live use.

Start This:
Start this capture device, if not already running. For debugging only; not for live use.

[Magic]

Well, capture devices can take a long time to start up and shut down -- sometimes several seconds. And, as you realized, the number of simultaneous devices that can be used on any given computer is highly dependent on the hardware configuration (motherboard, USB controllers, etc.). You often have to stop all running devices before you can start a new one, which is why the first button is called "Stop All" rather than "Stop This".

Because it's all so finicky, it's hard to know exactly what will work at any given moment. That's why I didn't add MIDI control -- it would be hard to automate the MIDI in a way that would allow everything to function reliably.

I'm happy to have another look at this, but my question for you is, in the performance you are designing, wouldn't it look strange if you had 5- or 10-second gaps where no capture devices were running? Or would it be tolerable for your situation?

[SoundRehabAustria]

Thanks for your reply, Eric.

I understand that everything in the VidCap module is strongly dependent on hardware and hence difficult to support in professional software because as soon as things don't work as envisioned, the software will be blamed and not the hardware ...

In my current (test) case I have 2 webcams running at a time, but several plugged into the win7 PC. I need to stop all and then start individual webcams I want to use. In terms of performance this is surprisingly quick and apart from the brief flicker OK i.e. to stop and start by mouse click takes less than 1-2 seconds (which I could potentially hide using scene transitions).

It's really cool that the Vid Cap module keeps a still of the last picture, unfortunately it flickers to black and back to the picture ... so if "Stop All" would just keep the still image until "Start This" brings the new video feed it would be perfect ... and if I could start/stop by MIDI (even better: if I could also access the device list via MIDI to change cams in the module) I'd be a happy camper

However, if you think all of this is too dangerous to implement for all users, I'll be happy to use any workaround you suggest as long as they remain maintainable. I'm working on a song based show with a flexible playlist/song sequence. Hence, each song is a scene, and throughout the song I use MultiMix to step through a mix of visuals, photos and video feed plus up to 2 (out of 6) webcams which blend stage actions with prepared videos/visuals. So if stopping/starting webcams needs to happen via external scripts, I could find a way to incorporate that into the show setup, but you would need to give me some hints on how to achieve this.

One (limited) workaround that might be to use one Magic file per song and MIDI triggered scripts to open the Magic file at song start. This would allow me to use 2 pre-selected webcams out of the 6, would be maintainable and fit the dynamic playlist setup. Yet it requires MIDI to script triggering i.e. another layer in between programs and does not allow to change cams within a song.

BTW, is there a way to change the name of the webcam in win7 so that webcams of similar brand show up with different names?

[Magic]

Ok, let me think about this. It would be easy for me to let the Stop All / Start This parameters be linkable (which would allow for MIDI control), but having them linkable would also expose them to audio control, which could result in bad/strange things . So I can't make any promises.

Eventually, I do have plans to improve the VidCap module so that it will support more kinds of devices, including IP cameras, which will probably be a better solution for your situation (since it would theoretically allow for an unlimited number of simultaneous streams).

if "Stop All" would just keep the still image until "Start This" brings the new video feed it would be perfect ...

I might be able to improve that. I'll have a look.

So if stopping/starting webcams needs to happen via external scripts, I could find a way to incorporate that into the show setup, but you would need to give me some hints on how to achieve this.

Unfortunately the cameras have to be stopped/started inside Magic. Otherwise Magic wouldn't be able to access them.

One (limited) workaround that might be to use one Magic file per song and MIDI triggered scripts to open the Magic file at song start.

Currently you can't use MIDI to load/close projects, but it's an interesting idea and I will certainly add it to my list.

BTW, is there a way to change the name of the webcam in win7 so that webcams of similar brand show up with different names?

Nope . This is a known and annoying issue with Windows. It's the same for MIDI devices. It's up to the device driver to implement a better naming scheme, but most drivers aren't written with that much thoughtfulness.

[SoundRehabAustria]

One (limited) workaround that might be to use one Magic file per song and MIDI triggered scripts to open the Magic file at song start.

Currently you can't use MIDI to load/close projects, but it's an interesting idea and I will certainly add it to my list.

Thanks again for all your valuable feedback.

Just to add info for anyone else listening in: I realized it is possible to pass a cmd line / batch script instruction to Magic (even while it is open, which is really cool) like e.g. "magic SampleProjects\VidCap_Test_v02.magic" and it'll discard the current project and load the new one. This instruction I can trigger with a 3rd party MIDI translator tool (like e.g. Bome MIDI translator, which is not free but I do own a license and use it for similar batch cmd triggering).

[Magic]

Ah yes, that is a cool idea. Sometimes I forget what my own software can do. I must be getting old.

[SoundRehabAustria]

Making really good progress here. Got 8 webcams attached, can use 2 at a time and currently change between cams by loading different project files via batch cmd now if I could stop, start and change selected device in the VidCap module via MIDI (as discussed aboved) I could go beyond the 2 cam limitation and use more than 2 cam positions within one song

Test period is up in 3 days ... will buy several licenses as this will be a major add-on to our live performance ... and so far I have mostly only looked into how video and live feed could play together and not even used much of the visuals side yet

2 cams is definitely enough for now, but please if you find the time, consider upgrading the VidCap module