Review: Rhozet Carbon Coder 3

Back to the performance table, the next two lines illustrate performance efficiencies when producing files in multiple formats. As you can see, when producing one file to Windows Media, H.264, and Flash VP6 using the On2 software development kit (SDK), Squeeze was actually faster than Carbon Coder, primarily because Carbon Coder is less efficient than Squeeze when producing single Flash files using the On2 Flash SDK.

Probably for this reason, Rhozet switched to the Adobe SDK, which is multithreaded, allowing multiple cores to help produce the same file, and it supports only one-pass encoding. I discuss the qualitative aspects of this switch in what follows, but it’s obviously a winner when it comes to reducing encoding time.

Expanded Watch Folder Functionality
Most Carbon Coder systems are utilized by workgroups via watch folders, and this version of Carbon Coder features a significant upgrade to watch-folder functionality. For example, you can now add leading and trailing clips to each encoded file and apply audio and video filters to your source files, neither of which you could do in previous versions.

Now, you can also retrieve files from folders or FTP sites for encoding rather than simply encoding files placed in local folders—an awesome feature for service bureaus and others encoding files from remote locations. You can also set email notifiers for starting, completion, and/or errors and execute a command line to run a script after encoding, which is useful for integrating encoding with other applications.

In addition, you can add multiple targets to a watch folder, each with their own filters, notifiers, and delivery options, which include file delivery to remote locations on the network or FTP. You can even tag jobs to assign certain files to different encoding stations in your server farm, which is useful when only one station has licensed a particular codec or has a compression accelerator card such as the Tarari Windows Media co-processor.

Finally, you can now create and edit presets in Carbon Administrator; in previous versions, you had to do this in Carbon Coder. Overall, the watch folder is a key interface for many Carbon Coder users, and now, it’s much more functional.

Output Quality
All of this is nice, but to borrow from the high school Latin course that I did not take, the sine qua non of encoding tools is output quality. In other words, the sizzle is impressive, but how is the steak? Turns out it’s quite satisfying, actually, but with one or two spots of gristle. Let’s start with a look at deinterlacing quality.

You apply deinterlacing as a filter with several algorithms to choose from. While previewing these, I was reminded that Carbon Coder (and ProCoder) could use some work on the preview function, which shows letterboxes atop and below the video window, leading me to worry about whether they will appear in the final video (fortunately, they don’t).

I tried all available deinterlacing methods and found adaptive to be the best. The result was very good, though uninspired. That is, Rhozet avoided any artifacts that mar Sorenson Squeeze’s deinterlacing quality, but programs such as Telestream Episode and Apple Compressor (in the glacial "best" deinterlacing mode) produce slightly smoother diagonal lines. This is nothing average viewers would notice, however, unless they saw side-by-side comparisons and shared my admittedly hyperanalytic focus on deinterlacing quality.

In the meantime, compressing my standard test file to Flash, Windows Media, and H.264 formats yielded generally good results. As mentioned, Carbon Coder now uses the Adobe Flash SDK, which offers a simpler interface and lets you open multiple instances of the encoder, which you couldn’t do with the On2 SDK.