If You're Looking For More Info About The AVCHD Codec, Read This! (page 2)
Log and Capture Using Tape
With tape media, your computer must first log the video clips that you want to import to your project. Logging in its simplest form defines the in and out points of a video clip, using the timecode on the footage. Logging a clip tells the video editing application that there is a video clip of interest between these two points in time. Then, you must tell the video editing application how to acquire this data. If it's on a videotape, you'll tell the application to capture this data. Capturing happens in real time. The video editing application cues up the tape and acquires the digital video stream of bits from the in point to the out point you defined when you logged the clip.
Log and Transfer Using Random Access
In the Log and Transfer process, the logging is the same in principle. Although, because AVCHD is stored on solid state media, the data can be randomly accessed and/or more easily controlled with virtual fast-forwarding and rewinding. In this way, logging in and out points can be done much more quickly, or the individually recorded video files can be simply flagged for import. Once the in points and out points or individual video files have been logged, the video editing application will transfer the footage to a video format that is much more edit-friendly than the native AVCHD format. This conversion can be time consuming as the computer processor chugs away. In this transfer process, we front-load some of the processing needs by converting your AVCHD footage to a video format that your application prefers to use. The transfer typically happens more quickly than real time, meaning that transferring an hour of footage will take less than an hour. It really depends upon your computer's processing speed.
In the end, you'll end up with file sizes that are generally larger than AVCHD, but they won't demand as much processing power during rendering of effects. Some applications will even allow for realtime effects, meaning that there will be virtually no render time for these files.
It's important to keep in mind that, at this point, you're no longer editing AVCHD. You'll be working with a totally different video format. That means you'll need to keep your AVCHD files archived just in case you need the source files if anything should go wrong.
A benefit of AVCHD is that its relatively small file size simplifies archiving. Depending on your shooting settings, AVCHD files can be much smaller in file size compared to other video formats. In some cases, you store twice as many minutes of footage (at lower quality settings) using the same amount of storage space. This is ideal for consumer shooters who do a lot of shooting but don't want to spend a great deal of money on storage space.
In the end, importing AVCHD footage to your video editing application is still faster than traditional tape-based media. Native support is by far the best in terms of ease of use. Many consumers just have a hard time grasping the Log and Capture or Log and Transfer experience. You also get the benefit of saving time at least at the beginning of the editing session.
What About Professional Editors?
The AVCHD format is now available on a variety of professional camcorders and is being used by professional videographers as a low-cost alternative that produces high-quality results. If you're comfortable working with intermediate codecs, then AVCHD can be an excellent source for your video files. The same file-size advantages are great for prosumers, too. However, most of these projects will be shot at higher-quality settings, in which case you won't save much space compared to the HDV file format. But AVCHD is still a more efficient file size than most professional video formats and can produce high-quality video that is comparable to more expensive formats.
Recommendations for the Editor
The typical consumer shooter that is producing family, travel or other non-professional videos will find AVCHD to be a good fit for them. We recommend using a video editing application that supports AVCHD natively. This will make the import process as easy as a couple of clicks of your mouse. You might have to be more patient, waiting longer for renders, but, for the casual editor this will be the best choice. Consider going easy on the special effects, which is generally a good rule of thumb.
For the professional, the greatest benefit comes from using a cheap recording medium. But professionals can also put native import to use. If you have video projects that require an incredibly short turnaround time, using an editing application that natively supports AVCHD can help make it possible to complete video projects faster than ever before. If your aim is to spend more time with your project, being critical of each pixel, make sure your video application can transfer AVCHD to a different video format (most of them can do this). Then, take a closer look at which application has the additional support you desire. This will be different for each type of editor.
Overall, AVCHD can be a great video format to use. Its compression technology is superior in terms of creating small file sizes while keeping the quality in check. And, just like all video formats, you'll get the most of your video footage if you keep your source video archived and well-organized. Don't let the consumer-friendly recording mediums fool you into letting your good data backup practices slide. No video format will do the hard work of backing up all by itself. Now, that would be something!
Contributing columnist Mark Montgomery is a web content specialist and produces instructional videos for a leading web application developer.
