TOD
TOD is a recording format for use in digital tapeless camcorders. The format is comparable to XDCAM EX, HDV and AVCHD and it is used for high definition files. It is a file-based format that is stored on a random-access media.
TOD is an informal name of tapeless video format used by JVC in some models of digital camcorders. JVC, who pioneered the format, didn't explained meaning of the file extension, and the format was never given an official name. Some think that TOD stands for "Transport stream on disk".
In January 2007 JVC announced its first high definition tapeless consumer camcorder, the Everio GZ-HD7, which recorded 1080i MPEG-2 video to either a built-in hard disk drive or an SD memory card. Data rates, frame sizes and frame rate were comparable to 1080-line XDCAM and HDV video.
High definition video is stored in MPEG transport stream container files with TOD extension; in most other systems these files have M2T extension. Transport stream files can be converted into program stream files without recompressing the video itself. For example, FFmpeg, a free program, performs the conversion on Windows and Linux systems with the following command: ffmpeg -i myclip.TOD -acodec copy -vcodec copy myclip.mpg. Software, included with TOD camcorders, performs this conversion as part of capture process.
Despite the file structure being unique to this video recording format, the location for still images follows the standard agreed upon by many still camera manufacturers.
Specifications
| Name of format | TOD |
|---|---|
| Media | Hard disk drive, solid-state memory cards |
| Video | |
| Video signal | 1080/60i, 1080/50i |
| Frame size in pixels | 1440 x 1080, 1920 x 1080 |
| Frame aspect ratio | 16:9 |
| Video Compression | MPEG2 Video (profile & level: MP@HL) |
| Chroma sampling format | 4:2:0 |
| Compressed video bitstream rate | ~17 - 30 Mbit/s depending on quality mode |
| Audio | |
| Compression | MPEG-1 Audio Layer II |
| System | |
| Stream type | Transport stream |
| Media file extension | TOD (on camcorder), M2T (on computer) |
Playing and editing
TOD format is comparable with AVCHD, but cannot be directly played on consumer video equipment. Media files must be packaged into distribution formats like HD DVD or Blu-ray Disc, using authoring software. One of TOD recording modes, "1440CBR", has the same frame size, aspect ratio and frame rate as 1080i HDV, and can be loosely called "HDV on disk".
Future of TOD format
JVC was the only supporter of TOD format. In 2008 JVC released several hybrid TOD/AVCHD consumer models, and some AVCHD only models. Consumer high definition camcorders offered by JVC from 2009 onwards record only in AVCHD format. Professional JVC tapeless camcorders introduced in 2009 use XDCAM EX format, licensed from Sony. Like TOD, XDCAM EX employs MPEG-2 HD video encoding scheme. Unlike TOD, XDCAM EX uses MP4 container.
TOD format does not allow recording progressive-scan video, neither at "film" rates (24, 25, 30 frames/s) nor at "reality" rates (50, 50 frames/s). This limitation makes TOD format suboptimal for online video viewing, because most video hosting websites stream progressive-scan video. On another hand, AVCHD allows recording progressive-scan high-definition video at both "film" and "reality" rates.
