![]() In the end, the study compared files in three groups: I sent the file to a number of vendors (Apple, Microsoft, Nero, Real, and Sorenson Media) with instructions to produce files in five basic configurations, targeting 56Kbps modems, 3GPP cell phones, LANs (100Kbps and 300Kbps), and broadband (500Kbps).įrom these codec benchmarking efforts, I produced files with the Macromedia Flash 8 Video Encoder, Autodesk Cleaner XL 1.5, Canopus ProCoder, Sorenson Squeeze, and On2 Flix Pro Encoder. This time, I started with a test file with 42 different scenes divided into five categories: business, action, entertainment, animation, and pan and zoom. There were no frame shots and no analysis I sold the CD with a dual-window player program that let you load and play the files side by side and draw your own conclusions. I encoded all the test files on an 80486 computer that took roughly 45 minutes to encode each 20-second clip. Experiments also included on the disc swelled the number of files to about 300. This product analyzed five codecs (Cinepak, Indeo, Video 1, and Xing’s proprietary MPEG and RLE), using four simple test clips ranging from a talking head to high motion, encoded at seven different data rate/resolution/frame rate combinations. Back in 1993, I produced my first codec survey in a product called the Video Compression Sampler. But at the very least, this article should provide some food for thought for your next encoding session.įormalities out of the way, let’s get started. If I provide sufficient incentive to convince you to buy one or more reports, so much the better. You know the drill: this article is designed to describe the studies, providing sufficient relevant information to make it worth your time to read the article while not giving away the vital information contained in the study. As such, I’ve spent the better part of the last four months playing files produced by a number of codec vendors and encoding, playing, and re-encoding test files that I produced myself. In the interest of full disclosure, I’ll acknowledge now that I’m the author of three research reports published by that benchmark codec and encoder quality. And whether your codec is at the top of the heap or the bottom of the barrel, the ability to eke out the last bit of potential quality via shooting techniques, encoder choice, pre-processing, or choosing between techniques like variable and constant bit rate encoding has never been more important. But that doesn’t lessen the importance of understanding how your chosen codec stacks up against the relevant competition after all, the most visceral observations your viewers will make depend precisely on quality. Video quality at a given bit rate, while historically the most important comparative metric between codecs, may now take a back seat to device compatibility, player ubiquity, royalty cost, or DRM scheme. But will the new ones all play on your Windows or Mac machine? After years of playing quality catch-up, MPEG-4 video is starting to shine, especially some of the new implementations of the Advanced Video Coding (AVC). Flash has emerged from a vector-based format for creative Web advertising to a mainstream video technology with a surprisingly powerful compression scheme. The availability of digital rights management (DRM) protection is critical to those selling their content, and royalty costs are becoming a consideration. Playback compatibility requirements have expanded, and you might be willing to trade UNIX playback for compatibility with a 3GPP cell phone. The codec world has gotten more complicated. These well-defined differences made it fairly easy to choose a compression technology based on financial, qualitative, or religious reasons (for QuickTime devotées, of course-and yes, we’re aware that QuickTime is really a "wrapper," not a codec in itself, but most of us use "QuickTime" as a convenient shorthand). ![]() QuickTime’s quality trailed the big two considerably at any data rate south of the gargantuan files used to transmit Star Wars, Episode One: The Phantom Menace via progressive download. Real charged for the server but was still cost-effective for many content distributors Windows Media was free but offered limited server and playback support. ![]() This article first appeared in the 2006 Streaming Media Industry Sourcebook, which was available free to all subscribers to Streaming Media magazine. ![]()
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