Shooting the Video
April 19, 1999
Creating RealVideo is as much an art as a science. If you have
the resources and are creating video specifically for the web
then there are a number of tricks you can use to get your video
to compress better. Let's start with the source video.
The better the video source the better the final result. You
should always record to the best medium available. The best
mediums in order of descending quality are:
- Beta or Betacam SP. This is the most common format for
professional production.
- DV or Digital Video. This newly emerging standard captures
the video in digital format so there is no tape degradation as
it is encoded from analog to digital.
- S-VHS or HI-8mm. These two formats are common for home
recording devices.
- VHS. The same as in your VCR. These tapes can have a lot
of noise both in the audio and video tracks that cause problems
with encoding.
If you have control over how the video is shot you can also film
it in such a way that compression is easier. Lots of fast cuts,
motion, and music are hard to encode to RealVideo. Talking head
shots of people are the easiest to encode. To help the final
quality, avoid camera pans and wipe transitions between shots.
Having lots of stationary objects in the background helps also.
Always use a mounted camera instead of a hand held one. Hand
held ones produce movement that causes objects to move around,
making it more bandwidth intensive to encode. If you use rapid
movement make sure that the important information doesn't occur
until a few seconds after the movement. This will give the new
object time to "resolve" before it becomes central to the scene.
The lighting should also be kept constant and uniform colors
should be used. Complex patterns in the background are hard to
encode.
Digitizing the Video
Once you've recorded the video to tape it needs to be digitized
to your hard drive. The video doesn't need to be captured at
full screen and 30fps because the final result is probably going
to be 15 fps at best for RealVideo. Capturing the video at 15
fps and 320x240 size is a good compromise. This will be a good
quality capture without taking up all the room on your hard drive.
Always be sure to capture the video at 24 bit or full color.
Lower color resolutions produce poor video quality with
noticeably blotchy color.
Video capture should always be done on a fast machine with a
fast hard drive. SCSI drives are preferable to IDE hard drives,
but the newer IDE drives are up to the task. Compressing video
is a very CPU intensive task and having a machine with lots of
memory and a fast CPU is important. I'd recommend a Pentium II
though a fast Pentium or Pentium Pro should work.
There are many capture cards on the market that will capture at
320x240 and 15 fps. The
Intel
Smart Video Recorder III is a
good low cost choice. It should be around $199.
There are also a number of programs that can capture video that
enters through the video-encoding card. The best desktop
solution is still Adobe Premiere. It works well with the
Intel Smart Recorder III. In Premiere you will be able to
select the format to save the video. I've always had a
preference for Quicktime, which is now in Version 3 on both
Windows and Macintosh. Quicktime has had a history of better
synchronization between video and audio. On Windows you might
also wish to record to AVI. Make sure to encode the video as
uncompressed so that you have the best possible digital source
file to encode to RealVideo. If you would like to output
RealVideo directly from Premiere there are plug-ins available
that allow you to do this. However, I usually take the digital
uncompressed file from Premiere and import it into RealProducer
for encoding.
RealVideo - Waiting on Broadband
Encoding to RealVideo
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