Video Capture on a Shoestring
Capturing video to your PC for streaming encoding can be done in a variety of ways. If grainy, low-resolution images satisfy your needs, you can go the webcam route, a la Jennicam. But if quality and versatility are paramount, you'll need a good video capture card. Add-on capture boards let you grab video from a variety of sources, including camcorders, VCRs and DVD players.
Such capabilities won't necessarily break your budget, either. We compared low-cost offerings from two of the most prominent vendors of streaming capture boards, Winnov and ViewCast. ViewCast's Osprey 100 and Winnov's Videum AV are cheap enough for streaming enthusiasts, but also include functions suitable for some professional-level projects. The Osprey 100 lists for $159, but can be purchased via ViewCast's resellers, online, for prices ranging from $149 to $199. The Videum AV, with a suggested U.S. retail price of $199, can be found online for prices ranging from $169 to $199.
I/O Options
Right out of the box, we noticed major differences between these two PCI boards. The tiny Osprey 100 -- barely longer than the PCI slot it plugs into -- would be much better suited for standard desktop systems than the 8.5-inch-long, Videum, which needs a good-sized tower case to stretch out in. The Osprey also features three different composite video inputs, allowing you to hook up a variety of sources at once -- although only one of those devices can be used at a time (the Videum has only one composite input). Both cards provide S-video input as well.
In terms of overall input flexibility though, the Videum takes the prize; it offers another video input for an MXC camera (such as the Color Camera sold separately by Winnov for $199), as well as a full-duplex audio input. Here's where the biggest difference between the cards comes in: while the Osprey 100 captures video only, the Videum supports both video and audio capture. With both on the same board, synchronization of the two media is more stable -- especially when capturing prolonged streaming clips -- than when inputting audio through a separate sound card. (ViewCast also offers an AV card, the Osprey-200). This convenience doesn't come trouble-free, however: The Videum conflicted with our current sound card. To solve the configuration problem, we simply disabled our existing sound card; a suitable option since the Videum also functions as an audio-out card. However, if you're partial to your existing sound card, this could be an inconvenience.
Ports on both boards could use better labeling -- the three composites on the Osprey 100 weren't numbered, and the S-video and MXC ports on the Videum appeared similar at a glance.
Both cards offer very basic capture software. Overall, the software interfaces for both boards were easy to manipulate, but this is due partly to their lack of complex features. Winnov includes a helpful feature that lets you drag and drop video clips into MS Word documents, e-mails, and so on. But in order to stream, you'll need a solid video editing package, such as Adobe Premiere, and streaming software like Real Producer Plus, to refine and process the video before broadcasting from a site.
The Videum ships with a physical manual, written in straightforward language that newbies to video capturing will appreciate. The Osprey manual, while also well written and thorough, comes in PDF on the installation CD. Call us old-fashioned, but we like being able to hold our documentation in hand while we work.
Performance DiscrepancyBoth boards support video capture at a resolution of up to 640x480 at 30 frames per second, but they exhibit best performance at lower resolutions. Using an Athlon 750MHz system with 192MB of RAM, at 320 by 240 -- a good resolution for Web streaming -- neither board dropped any frames during video capture, even up to 30fps.
But when we upped the stakes, capturing 1,000 frames at 640x480, at 30fps and in 24-bit color, we noticed some major differences in performance. The Videum board would only drop around 50 frames. But the Osprey 100 dumped anywhere from 200 to 500 of the frames during our tests. That's a marked discrepancy, although, to be fair, most captures won't be made at such high levels.
Lower-resolution clips translated into streamable media with few transition problems: 320x240 clips captured at 15fps were converted to 28.8Kbps Real Media files (meaning they were tightly compressed) at roughly 14fps with Real Producer Plus. But when we converted the higher-resolution, higher frame-rate clips into 28.8Kbps-ready SureStream media using Real Producer Plus, the Videum-captured video exhibited higher frame rates -- around 12fps, compared to 7fps for the Osprey clips.
For basic video capture needs, especially at lower resolutions and frame rates, the Osprey 100 is a good choice. It also allows the simultaneous connection of more composite sources than the Videum AV. But for a little more (depending on where you purchase), the Videum AV delivers better high-end capture performance and tosses audio capabilities into the mix.