Review: Rhozet Carbon Coder

Carbon Coder offers a good range of output presets that you can modify, or you can create your own. You can also create "profiles" that contain multiple target codecs. These work well in the watch folder environment because you can assign a profile to each watch folder and encode different source files to completely different parameters based on the folder to which you copy them.

After finalizing your preset, you click the Convert tab, which brings you into a third screen with a convenient preview window and a Convert button. But even though this seemed like the logical starting point for first five-target batch encoding, because our batch file contained a QuickTime target using Apple’s popular H.264 codec and VBR encoding, batch operation didn't work; only that file got encoded.

A quick call to tech support revealed a simple workaround; clicking the Queue button and choosing the One Job for each Target click box in the Job Queuing window. We also had to call tech support to figure out how to encode to Flash format; turns out you either need the Macromedia Flash 8 Video Encoder installed on the system, in which case you only get CBR encoding, or Flix Exporter ($199) for VBR and CBR encoding.

If Carbon Coder was a $400 retail product, this lack of documentation would be a significant flaw. The reality is that it’s a high-touch product with a long sales cycle that likely will be set up and administrated by technical users, with training from Rhozet an optional but highly desirable option. Don’t sweat over the interface, since the feature set, performance, and quality are definitely worth it.

Moving on to watch folder functionality, you can create multiple watch folders via the Carbon Coder Watch Folder Manager (see Figure 2). Again, since you can assign a different profile with multiple presets to each watch folder, you can easily automate the conversion of multiple type projects into multiple targets, something Squeeze can’t do, because Squeeze limits you to one watch folder with one target profile. On the other hand, the $500 version of Squeeze can FTP files to a designated location, while for most formats, you’ll need Carbon Server (or a third-party automated FTP solution) to achieve the same result with Carbon Coder, though Rhozet plans to add complete FTP functionality to Carbon Coder in the first half of 2007.

Figure 2 (below). You can create multiple watch folders with Carbon Coder, each with its own set of encoding targets and parameters.

Testing The Beast
I focused my testing in two areas, quality and speed. To test quality, I encoded files into Windows Media, QuickTime, Flash, and RealVideo formats, and then compared the files to best-in-class results produced by other encoders that I’ve tested. I encoded all test files to 500kbps, at 640x480 resolution at 30fps, with 468Kbps allocated to video and 32Kbps of audio. Though not widely used for streaming production, this full-frame size configuration tests a program’s deinterlacing capabilities while presenting a challenging data rate that reveals a program’s strengths and weaknesses.

I last evaluated batch compression programs while performing trials for the StreamingMedia.com research report, Proprietary Codecs 2006. In those tests, when producing Windows Media files, ProCoder placed last behind Sorenson Squeeze, AutoDesk Cleaner, and the Windows Media Encoder, in that order. Rhozet has obviously done a lot of good work since then, because quality was at least as good as Squeeze throughout, and in some clips, noticeably better, though most viewers probably wouldn't notice without side-by-side comparisons.