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MP 7,1 Will it be possible To Boot High Sierra (external ssd usb) Help!
- Thread starter jccmaxon
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Does the software run while High Sierra is hosted in a virtual machine? You would probably has to assign the USB devices (presuming a USB capture dongle) to the Virtual Machine.
P.S. can also boot into Windows if primarily just using the device as video recorder.
Thanks for answering. Avermedia u3 works natively in High Sierra but now I'm going to buy a Mac Pro and it won't work in Catalina. I would like to know what video capturer works in Catalina. My last option is to do it on windows but I prefer to record on Mac.
High Sierra doesn't run 'bare iron" on the the Mac Pro, but it probably does run inside a virtual machine layered on top of Catalina. Some virtual machine (VM) applications (e.g. Fusion ) allow you to assign a USB device (with some implementations ports/controllers ) to a virtual machine. There is some overhead of capture while inside a virtual machine but by and large what this is doing here isn't mach different than a simple drive read/write over USB. The virtualization overhead is likely low enough that the USB overhead large enough to mask out much of it. If attach this to a USB port with a USB controller that is doing nothing else there is a good chance the data rate is still good enough if the virtual machine app can establish a mostly direct link to the device. ( the date will get buffered quickly and present to the software in the VM with not much lag. )
For Fusion specially
"...
You can configure the virtual USB controller to enable USB 3.0 and 2.0 support. You can also configure the virtual USB controller to connect USB devices to the virtual machine when such devices are connected to the Mac while the virtual machine is active. The settings you select can persist across several VMware products, such as Workstation Pro and VMware Horizon 7.
If you have a Mac that supports connecting USB 3.0 devices, guest operating systems can connect to USB 3.0 devices as USB 3.0 and connect to USB 2.0 devices as USB 2.0. ...."
https://docs.vmware.com/en/VMware-F...UID-4819DA9E-3575-4C7F-9912-C2FFBA6CEAD6.html
So if Fusion "grabs" your USB device and hands it directly to the 'guest' High Sierra there is some chance this works. (if the virtualized Catalina storage is clean from the host OS that would be another choke point cleaned away too. ). If there is a relatively raw handoff ( based on USB ID ) then can work (i'm assuming the tag on id is to snag it as a raw device. That would also help keep it isolotated from the host system if no drivers there.). If layered on top of host drivers then yes a problem.
If the video capture is at the bleeding edge of the USB controller then probably not. But 1080p 8-bit color at 60Hz is only 3Gb/s. That can possibly work if the virtualization layer is optimized pretty well. Even 10-bit color is sub 4Gb/s (but that is in zone where a USB 3.0 only controller would typically start choking. ).
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Apple is completely overhauling their kernel driver API at this time. USB is one of the first areas impacted. Catalina can run now 'old' USB kernel extensions (drivers) but they are deprecated. Folks with non generic USB devices need to be developing new drivers ( and could have largely only started in June-July when got the flakey Catalina beta. Catalina has been flakey enough that a pragmatic start time was in October. ). Unless getting answer almost driver from the folks writing product drivers... i don't think there is solid future planning new right now. Even some of the manufacturers probably don't know if they outsource their driver work to 3rd parties.
There is going to a be slower uptick on Catalina USB drivers because if want to do it 'right' then it also means largely doing it over. So there is an unusually large amount of work to be done. And nobody is probably done with quality tested results , except Apple who got a longer head start.