Camcorder Video Formats Explained
You've shot your video, hooked your camcorder to your TV, and watched your creation in vivid, big-screen HD. Now you’re inspired to do more with it. You may want to jazz it up in video-editing software, view it on your PC or smartphone, publish it on Facebook or YouTube, or back it up to a hard drive, DVD, or Blu-ray disc.
To make such jobs easier, your camcorder saves footage in a particular digital video format, such as MPEG-4, AVCHD (Advanced Video Coding High Definition), HDV, or MPEG-2. At the core of each video format is a chunk of software called a codec (a term derived from coder/decoder). HD video file sizes are already beefy; but without a codec, the files would be even more cumbersome chunks of data.
Each codec squeezes down a source video file to make it easier to store and faster to transfer from your camcorder to an external device. On the other end of the transfer, the codec decompresses the file and restores it to the highest quality possible. However, the compression that consumer camcorders use is “lossy,” meaning that after the codec has its way with your file, you’ll never get the same-quality footage as you did before your video was compressed. That said, in many cases the dip in quality after compression/decompression isn’t noticeable to the eye.
The Big Two: MPEG-4 and AVCHD
For most camcorder shoppers right now, the choice of file formats comes down to either MPEG-4, a popular format for pocket camcorders and digital cameras, or AVCHD, a format growing in popularity among those using conventional HD camcorders and some digital cameras. Older, tape-based camcorders use HDV, but camcorder makers have largely abandoned tape for SD flash storage. MPEG-2 endures, but at the margins: Some higher-end HD camcorders and HD-capable digital SLRs use the MPEG-2 format. MPEG-2 is the also the main format in standard-definition camcorders, which have mostly ceded the limelight to their HD successors.
Of the two leading formats, MPEG-4 files are generally smaller and easier to work with, especially in video-editing programs. Both MPEG-4 and AVCHD use the same H.264 codec, but the MPEG-4 format includes much less data, which helps keep files comparatively slim and fast. MPEG-4 has also been around for many years, so it enjoys broad compatibility with applications, Web-based sharing services, and operating systems. That minimizes the time necessary to convert MPEG-4 files into other formats: Since most laptops can easily handle MPEG-4 files, users can quickly move MPEG-4 video onto a PC for editing, and then upload them to the Web.
AVCHD offers more features, but at the expense of larger file sizes, more-processor-intensive editing, and a possible need to convert clips to another format to get them to play nicely with your software or operating system. Each AVCHD file includes the ability to add metadata for each clip, thumbnail images, presentation tools such as navigation menus and subtitles, and a file system that lets you easily save video files to Blu-ray discs. The actual video clips save as MTS files.
AVCHD's rich extras add up to particularly big video files, so you may need to pump up your computer’s hardware to handle them. Your PC should sport at least a 2GHz multicore processor plus 4GB of RAM and a good graphics card for smoother (or at least less painful) AVCHD file editing.
Compatibility remains an issue when it comes to AVCHD. Panasonic and Sony launched AVCHD just a few years ago, and software is still playing catch-up. You may have to upgrade your video-editing programs and poke around for third-party applications to convert between AVCHD and other video formats. Windows 7 is the only PC operating system to offer native support for AVCHD; earlier OSs require you to install additional software even for file playback on your computer.
Also, some websites still require you to convert such files to a compatible format before you can post the video to them, although YouTube handles MTS files natively. All that said, support for AVCHD is steadily growing. Even some affordable editors, such as Vegas Movie Studio HD Platinum ($95) and Pinnacle Studio HD ($39), now support AVCHD. But video editors can vary widely in how much they support AVCHD, and in how well they wrangle these massive video files.
The situation is fast evolving. Check in with us for the latest video hardware and software reviews, and read up on the latest user experiences working with AVCHD files in forums at video-production sites such as CamcorderInfo.com, CreativeCOW.net, and AVForums.com.