Digital recording devices
are becoming popular in the digital world and are increasingly being
accessible to the home consumer. Some digital recording features can
already be found in digital cameras while the advanced recording
features are prominent in HD digital camcorders. However, higher
qualities and lengths of digital videos mean greater file sizes and
when it comes to sharing videos online
, file sizes should be reduced to avoid long delays in sending and receiving the entire clip.
Video
compression has gone a long way and their main objective still strives
to have the smallest file size possible while still preserving good
video and audio quality. MPEG4, H.264, and MJPEG are three DVR CODECs
that aim to compress the videos for transferring purposes. Each of
these formats have their own strengths and weaknesses.
First
came MPEG-1 followed by MPEG-2 and now MPEG-4 comes into the picture.
MPEG-4 is a massive upgrade to the MPEG-2 format that focuses more on
compression. It is a standard that can effectively compress both audio
and visual data for streaming purposes or to fit lengthy data on
optical media. Because it incorporates the existing technologies
of MPEG-1 and MPEG-2, MPEG-4 is also good for video conversations and
television broadcasts. It can shrink even the largest video files into
small pieces for faster transfers through the internet
or over a wireless network. Other data may be incorporated to the
MPEG-4 as well like images or video. MPEG-4 also sports some
interactive elements as long as they have the supported player to allow
some layers of the video to be manipulated.
H.264 otherwise
known as MPEG-4 Part 10 or AVC (Advanced Video Coding) takes the MPEG-4
format to another level and is advantageous over the older formats as
it contains inter-picture prediction features allowing up to 32 picture
references. It focuses on lossless methods and aims for flexibility on
a variety of different systems. Their lossless methods can also reduce
their file sizes even further than MPEG-4 formats making them ideal for
HD video. Still many mobile devices use the more popular MPEG-4 format.
MJPEG
is another format that may not be familiar by everyone. MJPEG basically
comes from the JPEG format, which is highly standardized for
compressing images. The MJPEG follows that same process and adds other
stuff in streaming each image or frame together. The end result leads
to lower CPU usages compared to the other formats, but higher file
sizes leading to increased bandwidth needed for streaming.
Your
choice of DVR compression depends on the specifications of your system
and your intended use of distribution. This is why there is currently
no format that rules over all. If you plan to distribute video clips
for slower computers, MJPEG could be the choice. For better
compatibility with mobile devices and standard computers, MPEG-4 could
be a safe choice. If quality must be preserved while keeping the file
size small (preferably on high definition videos), H.264 is the best
choice. You can even try compressing the video in all 3 formats,
compare them all, and see what looks best for you.