Container and Codecs
A digital video file usually consists of
two parts. These two parts are called the “Container” and the “Codec”. The container refers to what the
actual file type or extension is, for example: .AVI or .MOV. Now, within each
of these containers there is a codec which is like a set of instructions that
specifies the specific coding and settings of how the video plays on your
player. A few popular codecs you may have seen before are: DV NTSC, DivX, Sony
YUV. There are much fewer video file containers than codecs, and each container
can have hundreds of codecs within them. Most of the popular computer video
software is actually preloaded with several of the most popular and most used codec
and container decoders to properly playback popular file formats. Odd or
proprietary types of codecs may require downloading specialty made codec packs
from external sources in order to play correctly.
A Multitude of Formats
There are literally hundreds of video
codecs of video formats. Because there are so many possibilities,
we may not be able to convert all video files into some of the less popular or
proprietary video formats. There are also some video codecs out there that require
expensive licensing that we currently cannot offer. Just like
.doc indicates a word file, .mov indicates a QuickTime move file; .wmv stands
for windows media video and so forth. Here are the most common video file
formats, in alphabetical order:
3GP File Extension (.3gp)
The 3gp format is both an audio and video
format that was designed as a multimedia format for transmitting audio and
video files between 3G cell phones and the internet. It is most commonly used
to capture video from your cell phone and place it online. This format supports
both Mac and windows applications and can be commonly played in the following:
•
Apple QuickTime Player
•
RealNetworks RealPlayer
•
VideoLAN VLC media player
•
MPlayer
•
MIKSOFT Mobile 3GP Converter
(Windows)
Advances Streaming Format (.asf)
ASF is a subset of the wmv format and was
developed by Microsoft. It is intended for streaming and is used to support
playback from digital media and HTTP servers, and to support storage devices
such as hard disks. It can be compressed using a variety of video codecs. The
most common files types that are contained within an ASF file are Windows Media
Audio, and Windows Media video.
AVCHD (Advanced Video Codec High Definition)
AVCHD (.mts) is a high end, high-definition
(HD) format which was originally developed by Sony and Panasonic for high
definition home theaters. It’s not really suitable for sharing due to the excessive file sizes,
but the format is becoming more and more popular due to HD camcorders using
this format. Video in this format would be best suited as the master copy of
your video project and serves as a great piece to edit with. AVCHD is still in
its early life as a video format and since it’s still fairly new, compatibility
with certain video editing programs may be an issue. Some video editing
software applications have begun to support this format but many of can not
fully handle it quite yet. Additionally, playback of AVCHD files requires
speedy CPUs and a sufficient amount of RAM. That alone makes this format more
difficult to work with but, on the other hand, it maintains high quality. As
time goes by, it will no doubt become easier to use and be more integrated with
editing applications.
.AVI (Audio Video Interlaced)
AVI format is a long-time standard
developed by Microsoft and has been around as long as digital video has. AVI
files (particularly when uncompressed) tend to be HUGE, way too big for the
internet or uploading to someone. AVI is more for the beginning of a video project
using it as something to edit off of, not the end. In that sense, it is not
really a sharing format. They’ll slide into just about any video editing
program and the quality is still high enough to be a master clip. AVI is windows-based and is virtually
universal. The problem is, not all AVIs are created equally and you can still
run into compatibility issues due to different codecs on the videos. The
important thing to know is that whatever streams inside the container (AVI) is
not necessarily the same from one AVI video to the next because the codecs used
for compression can vary from file to file. This is because AVI is what’s known as a “container
format”, which basically means it contains multiple streams of different
type data, including a control track and separate video and audio streams.
.FLV (Flash Video Format)
Flash video (FLV) is the single most common
sharing format on the web today. You’ll see the .FLV file extension on videos
encoded by Adobe Flash software to play within the Adobe Flash Player. Virtually
everyone (99%) has the adobe player installed in their browser and so this has
fast become the most common online video viewing platform. Almost all the video
sharing sites stream video in flash. You can upload formats other than flash,
and those sites will convert it into flash for streaming to the end user.
Notable users of the Flash Video format include YouTube, Yahoo! Video, MySpace,
and many others. Many television news operations are also now using Flash Video
on their websites as a way to keep viewers up to date at all times. Most of
those sites accept uploads in a handful of formats like QuickTime, mpeg4, or
wmv, and then they convert it to flash or MP4 before actually putting it out on
the net for viewing. In addition to the nearly universal flash video player,
FLV is popular because it gives one of the smallest file sizes after
compression yet it retains fairly good quality. This means that the videos load
quickly on the internet, and won’t spend a lot of time using up your bandwidth. If you self-host your
own videos, you should convert them to flash for greatest compatibility with
the highest percentage of Internet viewers. Although FLV’s are the
most common format found on the web today, the standard is moving towards the
use of using MP4 H.264 files within flash players as it is compatible with both
online and mobile (iPhone), not to mention some HTML5 browser support (Safari, Chrome).
.MPEG (Motion Picture Experts Group)
MPEGwas developed by the Motion Picture
Experts Group. This international group was established in 1988 to develop
standards for digital audio and video formats. However, they’re just one
of many groups looking to standardize and develop new technologies for digital
video.
MPEG-4 (.MP4)
MPEG-4 is another great sharing format for
the internet. It’s a small file size, but looks fairly clean in comparison with other
video codecs of the same file size. It’s the video format employed by a growing number of camcorders and
cameras and it is highly recommended this day and age. In fact, YouTube actually recommends that
users upload using MP4 format. YouTube accepts multiple formats, and then
converts them all to .flv or .mp4 in their back-end for distribution. As
mentioned earlier, more and more online video publishers are moving to MP4
(with H.264 as the video compression codec) as the standard internet sharing
format with use within both Flash players as well as HTML5 and most mobile
devices. This is the format that we recommend for online delivery of your
media.
.WMV (Windows Media Video)
A .WMV file indicates a windows media video
file. Windows Media Video is used for both streaming and downloading content
via the Internet. Microsoft’s Windows Media Player, an application bundled with Windows
operating systems, is built for WMV files. WMV files are of a pretty small file
size, actually one of the smallest. As a result of the low file sizes, the
videos are compressed so much they start to lose their quality in a hurry. In
fact, I’d say the resolution is pretty crummy in comparison to modern
codecs. But a tiny file size can be a real advantage in some situations. If you
get an email with an actual video attached instead of just a link to a video,
it is probably a wmv file. They are the only ones small enough to attach to an
email.
.MOV
.MOV is the file extension used to identify
an Apple Quick Time Movie. .MOV is an extremely common sharing format,
especially among Mac users. It is considered one of the best looking file formats.
While MOV files do look great, the files sizes are extremely big. Due to the
fact that QuickTime has not been a Mac-only program for quite some time,
QuickTime versions and players exist on almost all PCs. The vast majority of
the videos we personally upload to the web are QuickTime format, followed by
MPEG4. If you see a video file on your computer labeled MSWMM, be aware that
this is a windows movie maker project file and not a video or movie file
designed for sharing. MSWMM will only play within Movie Maker. When you want to
save your movie to share it, use Movie Maker to convert it into a sharing
format, such as .mpeg4 or .wmv. The difference between sharing formats and
project file formats confuses many people. No matter what video editing
software you use, a project file is designed for working on within the editing program.
You must convert the project file to watch it on any other player. Now, what
streams inside the container is not necessarily the same from one avi video to
the next as the codecs used for compression can vary. At DVD Your Memories,
when you opt for a video to hard drive transfer, we give you your video tapes
as video files in AVI format.
Real Media Format (.rm)
RealMedia is a format which was created my
RealNetworks. It contains both audio and video data and typically used for
streaming media files over the internet. Realmedia can play on a wide variety
of media players for both Mac and Windows platforms. The real player is the
most compatible.
Flash Movie Format (.swf)
The Flash movie format was developed my
Macromedia. This format can include text, graphics and animation. In order to
play in Web Browsers, they must have the Flash Plug-In Installed. The flash
plug in comes preinstalled in the latest version of many popular Web Browsers.
