Working with JVC Everio MOD & TOD files
In 2005 JVC came up with a brilliant idea of a tapeless camcorder that records onto a small built-in hard disk drive (HDD) instead of recording to magnetic tape. Turned out, JVC hit the goldmine, the concept proved viable and became popular among consumers. Next year Panasonic and Sony rolled out with their own tapeless camcorders, Canon followed the suit in 2007. First tapeless camcorders were recording standard definition (SD) video, later high definition (HD) models were added.
JVC HDD-based camcorder lineup is called "Everio". Standard definition models are identified with suffix "MG" in their model name, like Everio GZ-MG130, Everio GZ-MG255, or Everio GZ-MG555. High definition models are identified with suffix "HD", like Everio GZ-HD7 or Everio GZ-HD3. Some camcorders are able to record onto a secure digital memory card (SDHC) in addition to recording onto a built-in HDD.
This article discusses both standard definition and high definition JVC camcorders. You will learn about video format employed, how video is stored, how video files can be loaded onto a computer and used in different video editing tools.
Everio camcorders record video using the same encoding scheme, MPEG-2, but store it differently depending on whether it is recorded in high or standard definition. SD video is stored in MPEG-2 program stream files. Usually these files are given MPG or MPEG extensions, but JVC chose to assign them MOD extension. HD video is stored in extended MPEG-2 transport stream files, commonly known as M2TS, but JVC again chose a different extension, TOD.
SD video conforms to DVD-video standard, the same format is used for commercial DVD movies. The DVD-video standard specifies maximum allowable data rate, 10 Mb/s. Everio camcorders record at a slightly lower rate of about 8.5 Mb/s at highest quality setting to ensure compatibility with existing DVD players. It is possible to record with lower data rate as well, with considerable loss in quality. HD video conforms to MPEG-2 high profile, and is compatible with HD-DVD and Blu-Ray players. The maximum data rate in the highest quality mode reaches 30 Mb/s.
SD video can be recorded in traditional 4:3 ("fullscreen") aspect ratio as well as in 16:9 ("widescreen") aspect ratio. HD video can be recorded in widescreen format only. Widescreen SD video became the norm for TV programs in Europe and Australia a decade ago, but is rarely used in North America for anything but DVD movies. By shooting in widescreen mode you can "future-proof" your video, because all modern TV sets are widescreen.
You can think of a tapeless camcorder as of an external computer disk drive eqipped with a lens. Video is stored on camera's disk as computer files. When connected to a computer via USB port, the camera is mounted as an external disk drive. If the camera has both HDD and memory card recording capability, then the memory card will be mapped as a separate drive. You may need to format the memory card before usage. After the camera has been recognized and its disk has been mounted, you can navigate through the directory structure and copy video files onto the main computer drive.
Directory structure on both hard drive and memory card is identical. The root directory contains SD_VIDEO folder, which contains one or more program folders. Program folders have names like PRGXXX, where XXX is a number, like 001, 002, etc. Program folders contain, among other files, video clips, named MOVXXX.MOD or MOVXXX.TOD, where XXX again, is a number, given to clips in sequential order. The scheme below is taken from the GZ-HD7 User's Guide, and is modified to accomodate names of standard definition video files.
If you unable to see file extensions in the Windows Explorer, it means that the Explorer hides them from you. To display file extensions open Explorer, select Tools from the top menu, then Folder Options. In the dialog box select View tab, and turn off the option called Hide extensions for known file types.
Everio camcorders use FAT32 file system, which means that a file cannot exceed 4GB size. This corresponds to about 1 hour of SD video or 17 minutes of HD video on the highest quality setting. If you happen to record for longer, the camera will automatically create a new file after it reaches 4GB limit. When the camera splices continuos video into several files, it loses about half a second of audio at each splice point.
Accessing Video Files
There are several ways of loading video files from the camcorder onto a computer. First, you can install the utilities, provided with the camcorder, and use them to transfer and edit video. Second, you can access camcorder as a normal external hard drive, and copy files you need, using Windows Explorer or copy command. And third, you can use third-party tools.
In regards to using tools provided by JVC, I am not keen on it. After all, all the tools you need for file transfer are already provided by the operating system of your computer. Another reason for not using JVC tools is that I already have video editing program, in my case it is Sony Vegas Movie Studio. This program can open MPEG-2 files, edit them, and create video on DVD. Therefore, I don't need JVC tools at all, I haven't even ripped the wrapper off the CDs with the software.
Accessing the hard drive of the camcorder directly is the simplest, cleanest and fastest way to get video from the camera onto a computer. There are, though, couple of issues with this approach. First, to load video files in your editing application you may need to change MOD file extension to MPG, and TOD file extension to M2TS, because some editing programs check file type by its extension. Smarter programs allow loading any file, then analyze file structure, and decide whether the file can be accepted or not. Another reason for using third-party tools is if you shot SD video in widescreen mode, or if your editing tool does not understand M2TS HD video format.
SD video widescreen video bug
It may come as a surprise, but fullscreen and widescreen SD video have the same frame size in pixels, 720x480. Even more disturbing, if you divide 720 by 480, the result will be equal to neither 4:3 nor 16:9. If the math seems strange, it is because you got used to square pixels. Video industry often uses non-square pixels. The level of pixel "sqareness" is called pixel aspect ratio (PAR). Regular 4:3 SD video uses PAR=0.9, while 16:9 SD video uses PAR=1.2. In plain English, widescreen video has wide pixels, "normal" 4:3 video has narrow pixels.
Because both fullscreen and widescreen video have the same frame size in pixels, a special flag in the header of a video file tells the computer or a DVD player to treat video either as fullscreen or as widescreen. Now we got to the problem: the Everio SD camcorders do not set widescreen flag properly when you shoot in widescreen mode. Most Editing tools treat these files as regular 4:3 video, and what you see is horizontally squished picture with unproportionally tall people. This issue is not related to HD video, because HD is always widescreen.
Some editing tools like Sony Vegas, allow manually adjusting PAR for individual video clips, but you will quickly get bored if you have a lot of clips to work with. Other tools do not have such flexibility at all. Therefore you need to have widescreen flag fixed in your video files.
Luckily, there is a cure for widescreen ilness, called SDCopy.exe. This utility copies MOD files from the camera, giving them more conventional MPG extension, and, more importantly, sets "widescreen" flag in the file header.
For source directory specify the appropriate directory on the camera, for target directory specify a location on your computer. Select "set widescreen flag" checkbox, click "Start", and voila! your files are copied from the camera to the computer, and their format is corrected. A word of caution: if you set "widescreen" flag to normal 4:3 files, the image will look stretched horizontally, and people will look fat.
The SDCopy.exe utility is all you need to start working with SD video files, besides MPEG-2 codec (see below).
HD video transport format compatibility
Many editing tools, especially older ones, are unable to open high definition files, even if you renamed them from TOD to M2TS. These tools simply do not know how to read the MPEG-2 transport stream produced by the JVC camcorders. The solution is converting transport stream files to program stream files, that is, to regular MPG files. One of the tools that does such conversion is MPEG StreamClip. All you need to do is to rename TOD files to M2TS files (for some reason StreamClip may not read file header correctly if the extension is not right). Then load the M2TS file into the utility and choose Convert to Mpeg... from the File menu. The conversion is lightning fast, because MPEG StreamClip does not re-encode video, it only repackages it from one container format into another.
Despite minor annoyances, caused by non-standard file extension and usage of transport stream format instead of more common program stream, you are able to edit full HD video with almost any editing application. For example, I had no problems loading 1440x1080 video into Sony Vegas Movie Studio 6, which is not supposed to handle HD at all, but it works without a hitch. You can edit MPEG-2 video with the VirtualDubMod too, if you want. On the other hand, to edit AVCHD video you would need a new editing application that understands the new video format.
Watching and editing MPEG-2 video
To play MPEG-2 video you need an appropriate codec. Recall, that MPEG-2 is the same codec used for making DVD movies. Therefore, if your PC has come with a DVD drive, it most likely includes MPEG-2 codec as part of DVD playing software. If you have no DVD playing software, you may find your PC unable to play DVDs and standalone MPEG-2 video files. To remedy this situation you can either buy commercial DVD playing software, which includes MPEG-2 codec, or you can download a free codec.