MPEG-4 Video, a test with QuickTime 6 Preview
Recently I tested out the MPEG-4 Video codec in Apple's QuickTime 6 Public Preview.
MPEG-4 video is a lot like MPEG-2 video, except it's more efficient (smaller file sizes, but
it typically requires a bit more CPU power, depending on many circumstances).
MPEG-4 comes from a line of popular formats developed by the
Moving Picture Experts Group. Here are the popular
MPEG developed formats:
- Used for Video CDs (they could fit around 60 minutes of 'okay' quality video onto a regular CD.)
This format was popular in places outside of the United States (particularly in parts of Asia) but
was not really more popular than VHS which could store 120+ minutes of high-quality video on an
inexpensive cassette. (Some current DVD players will play these VCDs, but many do not.)
- Mainly used for DVD video, satellite TV and digital cable TV. The quality is excellent, and this
format allowed cable providers to move away from wasteful analog television transmissions, allowing
cable to carry more channels in the same bandwidth of wire. Two hours of the highest quality
MPEG-2 can take upwards of 9GB of space. (Conventional consumer DVD writers only write one layer
on a disc called a DVD-R, which can hold 4.7GB, or about one hour of video at highest quality.
Professional distribution allows for dual layered discs, and double-sided discs. This is how some
DVDs have widescreen on one side, and pan and scan on the other side, even when the movie is nearly
two hours long.)
- Was proposed for HDTV, but not needed because MPEG-2 covered what this was supposed to be covering.
People commonly confuse MPEG-3 with MPEG-1 layer 3 audio, which is the file format commonly ending
- Designed for internet streaming and digital media. Provides near MPEG-2 quality at a much lower
bit-rate, making storage and transfer of this media format much less expensive than prior formats.