Video Compression Rate
In order to export a large amount of high quality video footage onto DVD, the material must first be converted from the native DV stream to a format that all DVD players will recognize. There are so many codec's to choose from that for the beginner, it can be extremely confusing. Modern programs that now include export codecs into their authoring software will clearly attract those who really don't want the bother of figuring all of this out for them selves.
Before you are able to deliver video on a DVD, you need to prepare your clips and export them to a compatible format, which is MPEG-2. Window users have access to software such as Adobe Encore and Premiere pro, in addition to Sonic Solutions DVD it, Ulead DVD Workshop, Easy CD Creator, and Nero which offer an encoder with several advanced features and customizable parameters, however, if working on a Mac, your options are iDVD, DVD Studio Pro, Compressor, QuickTime Pro and Roxio Toast.
All DVD disc contains a recording that will remain digital at all stages of the process, which leads to improved technical quality. In addition to MPEG-2 video compression, many commercial DVD disc contain 5.1 channel Surround sound audio that has been encode into the Dolby AC3 format. Where shorter durations are involved, it's possible to use standard 650 or 700MB CD discs instead of a regular DVD disc.
Almost all applications will include a feature that allows you to set upper and lower limits to the encoding bit rates. You will probably find that, for an average 60-minute DVD recording, you'll need an encoding bit rate in the range of 6500 Kbps to 7500Kbps. The minimum bit rate for MPEG-2 is 150Kbps. The only way to be sure of what's best for you is to experiment and find out the advantages and disadvantages of the different codecs and different settings.
Not only is compression directly affected by the quality of the video material you're expecting to compress, but shaky camerawork with heavy use or the zoom will prove more difficult to compress than well shot, tripod mounted camera work. As you become a more experienced user, you'll want to take more control over the many aspect of compression. If your video clips are to be viewed over the Internet, you need to compress it even more than you do when saving to DVD disc.
The common frame size for streaming video is 320 x 240, running at 15 frames per second (fps). If you'd like your viewers to see every frame of your video at a larger size and frame rate, you might want to prepare the file for downloading rather than streaming. You compress the video using a codec that makes it smaller and more easily transmitted, while your viewers decompress the file, using that same codec, so they can watch it. These movies are watched using Windows Media Player, QuickTime Player, and Real Player.
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