A S t r e a m i n g M e d i a P r i m e r :
H O W D O I M A K E ( G O O D ) S T R E A M I N G M E D I A ?
Pre processing your video
Pre processing sometimes called optimizing removes non essential information from your video
and audio information that is diffi cult to encode and/or does not substantively add to the quality
of the streamed media. So pre processing prior to encoding reduces the burden on the compressor,
potentially saving time and CPU capacity. It also allows you to make some of the decisions about what
information will be included in the encoded media, rather than relying solely on your compression
software to make all the determinations.
S O M E T Y P I C A L P R E P R O C E S S I N G TA S K S F O R S T R E A M I N G M E D I A
GETTING THE PROPER
Normal or Accurate scaling. Unless you're
ADJUSTING COLOR AND
under time constraints, use the Accurate
function to anti alias and to reduce
Cropping your video
Brightness, contrast, hue, saturation
from the frame edges is a good starting
These are often subjective settings. Any
point to get rid of edge artifacts you might
Traditional video systems
adjustments needed depend on the source
not even be able to see without zooming
paint images on the screen in alternating
material and how it was captured. Experi
in very tightly, such as tearing or black
lines, in a process called interlacing. Com
mentation is the key to fi nding the right
bands around any of the frame edges.
puter monitors do not use interlacing to
settings for each project.
These anomalies can occur during capture
display video and it should be removed
Applies a non lin
and create unnecessary pixels that would
from video clips that will ultimately be
ear function to the amplitude values of the
waste precious bandwidth.
viewed on the computer. You can deinter
pixels, helping to create more whites with
lace in Adobe Premiere by selecting a clip
Pay attention to the aspect ratio when you
out brightening the entire range or more
in the Timeline, pulling down the Clip
crop, either maintaining the original and/or
darks without affecting the bright areas.
menu and choosing Video Options, then
keeping the dimensions to multiples of
Field Options, and checking the Always
Black and white restore
This is an
four. Compression algorithms often divide
Deinterlace box. Or you can deinterlace
option in Cleaner 5 that lets you adjust
images into blocks of 4x4 or 16x16 pixels.
a project globally by choosing the
only the very white or very black portions
Keeping the dimensions to multiples of
Deinterlace option in the Special Processing
of images, forcing values to pure black or
four assures that your aspect ratio won't
area of the Export Movie Settings.
pure white. The Amount slider determines
be reconfi gured during encoding to fi t
what values will be affected by the oper
the inherent constraints of the compression
When fi lm (shot at 24
ation, while the Smoothness slider adjusts
software. If you need to scale the image to
fps) is converted to video (at 25 fps for
values near the transition points. A typical
a particular window frame, make sure
PAL; 29.97 fps for NTSC), additional frames
use of Black and White restore is reducing
you maintain that aspect ratio 4:3, for
are added, in a process called telecine. You
noise in fl at areas such as black back
example, for a 160x120 window.
can use inverse telecine to discard those
grounds behind titles.
To crop your footage in Adobe Premiere,
extra frames that would just burden your
drag and drop the Crop fi lter from the
encoder. You'll fi nd information on how to
AUDIO PRE PROCESSING:
Video Effects palette to the Timeline.
do this with Adobe Premiere, in the Support
Extraneous noise makes
Then, in the Effect Controls palette, adjust
Knowledgebase at www.adobe.com.
the audio signal more diffi cult to encode
the crop setup to reduce the picture by 5%
Two dimensional fi ltering
and uses up precious bits. When encoded
on each side, or to whatever amount you
bandpass, and high pass fi lters use math
for streaming, the effects of noise are
choose. You can also crop your movie
ematical functions to adjust the pixels of
usually amplifi ed, and can result in an
globally by using the Special Processing
which images are comprised, in order to
functions in the Export Movie Settings
alter image qualities. By using these fi lters
when you output.
to selectively or uniformly blur images or
Enhancing the signal
how well your audio was recorded, you may
Video is typically captured
sharpen edges, you can effect the differenc
need to uniformly or selectively boost or
at a larger frame size than you are likely
es, from frame to frame, that the com
cut the signal to arrive at the best level to
to output for streaming. If your audience
pression software will have to deal with.
encode for the Web. You can also enhance
is comprised only of broadband users and
Cleaner 5 offers three such fi ltering options:
the signal using a variety of effects, or
want large frames, you can compress your
Blur, Unsharp Mask and Adaptive Noise
fi lters, that alter different qualities of the
video at capture size. But, if you are stream
Reduction, each with a variety of different
audio, such as reverb or echo.
ing to users with slower connection speeds
settings for a wide range of fl exibility.
namic Medianamic Media
and/or you want to improve image quality
Adobe Premiere 6.0 includes a sound studio
and/or achieve higher frame rates, you may
style Audio Mixer and 20 audio fi lters that
want to scale your video to a smaller size.
make it easy for you to pre process your
The Cleaner 5 module of Adobe Premiere
audio. The Media Cleaner EZ 5 module built
offers convenient scaling options. The pull
into Adobe Premiere 6.0 also provides tools
obe Dobe D
down the Scaling Quality option in Media
for optimizing your audio.
Cleaner EZ 5 allows you to choose Fast,