Monday, August 27, 2007

bringing the digital audio workstation back to life

After about six months in a disabled state, I spent most of yesterday resurrecting my digital audio workstation. It is a 1.8Ghz Pentium IV running Win2K and a host of audio apps, mainly Cubase SX and Reason 2. My main SCSI hard drive, a Western Digital 18300 connected via an Adaptec 29160N PCI card, was a bit flakey and gave me errors on bootup. I resolved them by going into the Adaptec BIOS configuration menu (CTRL-A on boot) and checking the drive for errors. Thankfully, this procedure resolved the errors and I was able to boot successfully into the system.

The next task was to reinstall my M-Audio Delta 66 card. I couldn't find my driver disk, so I downloaded the latest off of their site (http://www.m-audio.com). M-Audio's site is very easy to navigate and I was able to find and install the drivers within a few minutes. The drivers required two reboots, which was somewhat of a pain.

I am going to do a favor for a friend by capturing some old video from VCR, so I installed my old ATI All-in-Wonder Radeon 8500DV. This will allow me to grab video via a composite source, my old VCR. Normally, I'd try this task in Fedora, but I really need to get the capture completed quickly and Win2K seems the quickest route. However, when I put the card in, the box booted, but just gave me a blinking prompt without any BIOS information appearing. Uh boy. I went through the laborious task of yanking all the other cards out of the machine, reconnecting all the IDE cables and trying a different card just to get the BIOS screen to appear. Once this was done, I put the Radeon 8500DV back in, checked the seating of the card and booted up. Thankfully, the machine booted properly this time. But these steps wasted about 45 minutes.

Once the machine booted into Windows, it seemed that I already had the Catalyst drivers installed (http://ati.amd.com/products/catalyst.html ), so the card was recognized right off the bat. This was a nicety after the other problems I've had so far.

With the audio and video hardware finally installed and working, I tried running a basic test of audio input via the Delta 66. When I did this, I found that Cubase SX selected the onboard audio drivers of my ASUS P4S333 motherboard (http://usa.asus.com/products1.aspx?l1=3&l2=0&l3=0&modelmenu=0&share=txt/60), the C-Media CMI8738. Cubase seems to get the primary audio card information from Windows, so I needed to go into the Sound settings in Control Panel to select the Delta 66 as the main audio interface. Once this is done, Cubase then recognizes the card and assigns it to the project. I was very happy to hear noise out of the card and see audio levels flickering in the M-Audio software Monitor-Mixer!

Next step is to get MIDI running with my M-Audio MIDISport 2x2 MIDI interface, with input from the electronic drums and Handsonic and keyboard. I'll try this one tonight. If I have anything interesting to say about this task, I'll let you know, but I'm hoping it will be uneventful.

cheers,
the mule

Tuesday, August 21, 2007

Hello from On Holiday!

Sunday, August 05, 2007

screen capture using Cinelerra

Unfortunately, capturing video live into Cinelerra CVS is broken, as of 1/21/2009. However! I tested it out and Cinelerra CAN capture screen activity directly to the timeline! This is a really nice feature.

The basic steps are:
1) go into Preferences -> Recording
2) select the destination File Format and whether you want to capture audio, video or both
3) set Audio In prefs (TwosComplement and keep your sample rate low!)
4) set Video In prefs (MPEG4 worked for me)
5) set Record Driver to Screencapture (set size of captured frame here and FPS)
6) apply your changes
7) press "r" for record and you'll see the Cinelerra Video In box popup with the active display
8) click the record button, which is the red, round button next to Transport: and you'll start recording as noted by the Position
9) click the stop button, which is the white square button next to Transport:
10) select your insertion strategy (I left mine at "Paste at insertion point"
11) click the green checkmark or just hit enter to accept and paste your captured video

If you click the "Monitor Video" radio button, you'll see the part of the screen to be captured.  If you have dual monitors, note that you can pan the area of the desktop that you can record by click-dragging the desktop area within the "Monitor Video" window.  I stumbled upon that undocumented feature.

The resolution of captured video is proportionate to the speed of your system overall. Thus, faster CPU, high-speed memory and striped hard drives help get you screen captures that are larger in resolution and smoother in playback. But there are other things than hardware upgrades that you can change in Cinelerra in order to increase the relative smoothness of your video capture. By "relative smoothness", I mean decreasing video frame drops and clipped audio samples.

For better performance, do the following:
- record using a lower audio sample rate (22Khz or below)
- record to an uncompressed video format. RGB/RGBA works well for me. I do this because compressed video formats like MPEG4 tend to hog CPU power and thus contribute to video frame drops. Your final output will most likely be a compressed format, so the uncompressed format will only be an intermediary that you will discard. Be careful with uncompressed formats, though! Five minutes of video sucked up about a gigabyte of disk! :)
- limit your mouse movements while recording. Try to use keyboard shortcuts to open, close and move windows

Here's a video of the process: