Video/Audio Sync?

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05-06-2008, 12:34 PM
SourceChild

Quote:

Originally Posted by samsc

using a mac to playback audio from the sound output - is buyer beware.

I am curious at your feedback. I've got three different venues that have been playing Audio off their Catalyst machines for years. Easily over 5000 separate instances of playback with audio and I've never heard of problems. (Granted I had a few bugs with V3.3 and older on the old G5 machines.)

Now I have done things in different cases. Sometimes it was literally the 1/8" mini phone jack connected to a stereo DI. Other times an external USB or Firewire Audio device. Most times using SDI audio.

Where have you seen problems occur most.
05-06-2008, 01:45 PM
samsc

Quote:

Originally Posted by SourceChild

I am curious at your feedback. I've got three different venues that have been playing Audio off their Catalyst machines for years. Easily over 5000 separate instances of playback with audio and I've never heard of problems. (Granted I had a few bugs with V3.3 and older on the old G5 machines.)

Now I have done things in different cases. Sometimes it was literally the 1/8" mini phone jack connected to a stereo DI. Other times an external USB or Firewire Audio device. Most times using SDI audio.

Where have you seen problems occur most.

it works - its used a lot -

but because using audio playmodes - as i have said before - apple makes the movies prioritise audio - not video- so when you do this the video sometimes does not playback as smoothly as without audio. if the computer is doing too much - apple skips video frames.
this is a bigger problem with systems with only sata discs - and people using lots of layers at the same time.
hunting around for audio as well as video - and they are often on different parts of the discs - within the same movies- makes the rotational latency issues more critical.
05-06-2008, 01:49 PM
samsc

Quote:

Originally Posted by SourceChild

I am curious at your feedback. I've got three different venues that have been playing Audio off their Catalyst machines for years. Easily over 5000 separate instances of playback with audio and I've never heard of problems. (Granted I had a few bugs with V3.3 and older on the old G5 machines.)

Now I have done things in different cases. Sometimes it was literally the 1/8" mini phone jack connected to a stereo DI. Other times an external USB or Firewire Audio device. Most times using SDI audio.

Where have you seen problems occur most.

a more general point-
multitasking general purpose computer systems do not prioritise the allocation of any specific system resources to a single task.

a standalone audio playback unit - because it will be designed with only one function - and system resources prioritised to that single function - will likely be more stable. though not always.

---

In the design of general computer systems - it does not matter if a program crashes - or the OS goes and does something else for a few seconds-
In audio visual applications running on general purpose computers - ths behaviour is not appropriate - and there is no means of controlling these things in the operating system.

We have been lucky that it mostly works - almost all the time. and testing on shows over many years has shown adequate performance under long and continuous use. but this is still not exactly how these things are designed.
05-06-2008, 02:46 PM
SourceChild

Actually Richard,

You're exactly right. I wasn't sure though if you had additional considerations I haven't considered.

I guess it's a good thing to point out that I run scripts after each big event that set the state of the computer back to the "out of the box optimized' state. I tend to take for granted that the majority of people don't Re-Image often.

On a thought though... I've tried in the past to play audio files in PLAudio mode on Catalyst. Is there a way to integrate an audio only play mode so Catalyst can play audio as well as video files? ...and is there a way to input/output the timecode of it?
05-06-2008, 08:01 PM
Peter

Quote:

Originally Posted by SourceChild

I guess it's a good thing to point out that I run scripts after each big event that set the state of the computer back to the "out of the box optimized' state. I tend to take for granted that the majority of people don't Re-Image often.

Could you explain a bit more on "out of the box optimized"? And do you want the share the scripts or i can try to write my own if i understand this a bit better.
18-06-2008, 10:08 PM
SourceChild
Quote:

Originally Posted by Peter

Could you explain a bit more on "out of the box optimized"? And do you want the share the scripts or i can try to write my own if i understand this a bit better.

Sorry it's taken me a while to respond, I've been busy.

One thing very important to a Catalyst server is the ability to run without unforeseen issues. Ideally, the best way to make a Catalyst machine is to do the following:
- Use a MacPro not a G5 (preferable a 2nd Generation Intel)
- Buy a new SATA disk (this becomes your installation source)
- Wipe and "Zero" your system hard disk using the Installation Disk Utility
- Install your Capture Card (LFG4 or Decklink or the new Phoenix once released)
- Install your Mtron SSD disk (I suggest 2 64Gb disks in a stripe)
- Assure you have at least (my recommendation) 8Gb of Memory
- Make sure you have an x1900 Video Card (or Geforce 8800 or Quatro FX xx00)
- Clean your fans and heat syncs and connectors
The new disk I talked about becomes your installer disk. First, go to x86 project and lookup instructions for creating a bootable installation disk out of your spare SATA disk. (I say x86 Project because I am a hacker and their forums explain this the best. Granted you won't be creating a "Hackintosh").

One you have the Catalyst machine ready to go and your new disk formated GUID with the proper EFI, copy all the following to your new disk.

(Make sure you have an installation CD for Leopard)
- Leopard Full install DVD
- 10.5.3 Leopard Update Package
- Drivers for your Video card (not the newest, the ones we've posted here that "work")
- Drivers for your video card (ONLY IF APLICABLE and "drivers" only, not software)
- Drivers for your USB card (some of us do the HES thing where we put our dongle inside on a PCI USB card)
- The drivers for the Aladdin USB Software Key
- The newest version of Catalyst (currently m165)
- Read-Only Folder with whatever you decide to be your "Stock Content"
- System initialization scripts which include:
- --Applescripts to wipe the System disk and write Zeros
- --Applescripts to wipe the Mtron disks and write Zeros 3 times
- --Applescripts to build an Mtron disk Stripe Set
- --UNXI Shell-scripts to automate install
- --Applescripts to update to 10.5.3
- --Applescripts to install drivers for video capture
- --Applescripts to install drivers for video card
- --Applescripts to install drivers for PCI USB
- --Applescripts to optimize Quicktime
- --UNIX Shell-scripts to remove Time Machine
- --UNIX Shell-scripts to disable ExposÃ©
- --UNIX Shell-scripts to disable Dashboard
- --UNIX Shell-scripts to halt .mac services
- --Applescripts to create a Catalyst folder system
- --Applescripts to copy Stock Content to the Mtron Disks
- --Applescripts to install Catalyst into directories based on show type
- --Applescripts to install dongle drivers
- --Applescripts to disable Screen Saver and Energy Saver
- --Applescripts to install your different versions of Catalyst into the Dock

Loosely, this is how I do it. I wrote all these scripts based on research I conducted into how to do them. All of the scripts are separate and independent of one another so as to prevent errors. I have a global scripts that executes all of the aforementioned scripts in a progressive order.

Basically, when I get a Catalyst back from a rental where someone other than me has used it, I stick in the Installation Hard Disk and run the first script. Then about 4 hours later, I walk back and have a clean machine.

If anyone is interested in these scripts, I will make them available for sale once I have tested them thoroughly to make sure they are solid. I will offer them at a nominal price and shortly I will be releasing a full application that does all of these tasks. The application will not be ready until mid fall but the Script package will be ready by end of summer.