Video Production for Streaming

Producing Video
for the Web

Jan Ozer
Doceo Publishing
jozer@doceo.com
276-238-9135

Agenda
The streaming environment
Production
Setting the scene (background and clothing)
Lighting
Camera positioning, framing and motion
Optimizing camera controls
Editing/Preprocessing
Choosing your targets
Producing to your targets
Encoding
Copyright © 2007 Jan Ozer, All Rights Reserved

1

The Streaming Environment
Concepts
Bandwidth
Delivery modes
Resolution
Data rate
How streaming is different from analog


Why Do I Care About Bandwidth?
What is bandwidth?
Viewer’s connection speed
Why is it important?
Controls your viewer’s ability to retrieve and play
video smoothly
Higher delivery bandwidths mean higher data
rates, which means better quality


2

What are My Delivery Options?
Streaming
Viewer clicks, video quickly starts to play
Plays without interruption until finished
Progressive download
Viewer clicks, video quickly starts to play
Video may stop during playback, but stored locally
Once completely downloaded, plays smoothly
Download and play
File downloaded completely before playing


Why is Delivery Mode Relevant?
To stream effectively:
Must compress to bandwidth available to viewer
Since compression degrades quality, streaming is the most
challenging delivery mechanism
Must distribute efficiently from the host (which often means
a streaming server)
Don’t have to compress to effective bandwidth, which may
mean higher quality
But, user may have to wait (e.g. QuickTime movie trailers)


3

Why is Resolution Important?
Most video starts life at 720x480 or higher
Most video is scaled down for streaming
320x240 is the general minimum
Ranges up to 640x480 and higher
Resolution is key quality factor
At a set bit rate, increasing resolution degrades
quality because you must compress more pixels
Can’t say that 300 kbps is “adequate” without
knowing resolution

Why is Data Rate Important?
Largely determines video quality
At static resolution and frame rate, increasing bit
rate increases quality
Because we have to pay for it


4

How is Streaming Different?
When truly streaming (not progressive
download or download and play)
Typically have to compress video significantly
to:
Meet end user bandwidth requirements
Meet bandwidth costs
Streaming is “lossy” - the more you compress, the
more you lose quality-wise


When to Customize Production for
Streaming
Similarity to
Analog and DVD

No difference

320x240

640x480

Must produce
Exclusively for
streaming

Delivery 1.5 mbps 1 mbps 500 kbps 300 kbps 100 kbps
Bandwidth


5

What’s this Mean?
At 1-1.5 mbps (640x480), most video looks fine
without special care
As data rates decrease, have to:
Limit motion in video (camera and subject)
Choose compressible backgrounds and clothing
Generally use compression friendly techniques
The lower the bit rate, the more you care


Streaming Environment -
Conclusion
Questions?


6

Producing for Max Streaming
Quality
Production
Setting the scene
Choosing a background
Clothing
Lighting
Camera positioning, framing and motion
Optimizing camera controls


Which Backgrounds Work Best?
Backgrounds
What’s different between streaming and analog
production?
High level goals for choosing a background
Best practices
Choosing a background:
For my in-house studio
While on location
Conclusion and checklist


7

Background - What's Different?
Contrast issues:
Very similar between analog and streaming -
need to separate subject from background
Other issues:
Backgrounds with motion can severely degrade
compressed video quality
Poorly chosen backgrounds (well lit, reflective
blank walls) can quot;createquot; noise


What do I Care About When
Choosing a Background?
Provide contrast with talent
Obviously relates to clothing worn by talent
Avoid color and contrast extremes
Choose one that compresses well
No motion
Low detail
No wide open spaces (embrace clutter)
No highly saturated colors


8

Contrast
Good contrast Bad contrast
Deloitte - dark grey suit, P&G - blue/blue
light blue back Price - black/black
Cranky Geeks - brown NIST - black/black
suit, black background Real - blue/blue
HP - grey shirt, dark
background
HP - blue shirt, brown
background
Amex - light blue shirt,
grey background


Contrast
Good contrast Bad contrast
Deloitte - dark grey suit, P&G - blue/blue
light blue back Price - black/black
Cranky Geeks - brown NIST - black/black
suit,black background Real - blue/blue
HP - grey shirt, dark
background
HP - blue shirt, brown
background
Amex - light blue shirt,
grey background


9

Avoid Color/Contrast Extremes

Brightness extremes hard for
camera/codecs to preserve
Color extremes make it tough to
maintain contrast


Avoid Color/Contrast Extremes


10

Avoid Motion
Akamai
NAB


Avoid Wide Open Spaces
DON'T - Use flat, well-lit, light
color backgrounds without
some quot;clutter.
DO
Add quot;clutterquot; to the background
to contain artifacts
Darken background to
Reduce detail
Reduce reflection


11

Avoid Highly Saturated Colors

DON'T use highly
saturated colors – Which
tend to create motion in
the background
DO - Use more muted
colors


Avoid Fine Patterns

DON'T - use backgrounds
with fine patterns and/or
decorative lighting.
DO - use a simple
background with little visible
detail


12

Creating the Perfect In-House
Background
Simple is better
Flat black works well
MS got fancy and
lost contrast
Be Flexible
Curtain system with
multiple simple
backgrounds


Building the Perfect
Background - Office
1 stand (~ $100 US)
2-3 backgrounds
(~$130 US)
Flat black
Dark grey
Light blue
Under $250, you’re set


13

Background - On Location
Need “on location” feel
Curtains and portable backdrops out
How to create compressible set?


Background - On Location
Avoid contrast
extremes
Avoid complex
textures and shapes
Limit detail with
lighting (darken the
background)
Or by blurring the
background with
camera settings
Avoid backlighting


14

Background Checklist
Does the background provide contrast with subject's face,
clothing and hair?
Are there extremes in contrast and/or color
Is there extraneous detail in lighting or pattern?
Is it moving?
Are the colors highly saturated (rich reds and blues)?
Are there well lit, wide open spaces?
Are there any light sources like lights or windows?
Have you tried compressing the footage and viewing the
results?


What Should Talent Wear?
What’s different between streaming and
analog production?
Feng Shui in clothing and backgrounds
Avoid contrast extremes
Other issues
Clothing checklist


15

Clothing - What's Different?
Must be more sensitive to detail that can
produce compression artifacts (jewelry,
glasses, hair)
Similar in other aspects, though compression
exacerbates issues
Contrast (no black and white)
Details (no stripes, herringbones)


Clothing Checklist
Clothing
Solid colors - dark blues, grays or browns.
Avoid white and light blue (which looks like white on camera)
Advise in advance to match background, and perhaps bring
alternatives (or lighter shirt/darker coat)
Hair
Pulled back (Loose ends disappear once compressed)
Jewelry
Some OK, large bling is additional detail and reflective
Glasses may require special lighting (generally from
the side) to avoid glare


16

Clothing Checklist
Clothing
Solid colors - dark blues, grays or browns
Avoid white and light blue (which looks like white on camera)
Advise in advance to match background, and to bring
alternatives (or lighter shirt/darker coat)
Hair
Pulled back (Loose ends get messy after compression)
Jewelry
Some OK, large bling is additional detail and reflective
Glasses may require special lighting (generally from
the side) to avoid glare


How do I Light for Max Quality?
analog production
Overview
Decision time - flat lighting or shadows
Producing three-point lighting (bonus)
Producing flat lighting (bonus)


17

Lighting - What's Different?
Overall, analog and streaming are similar,
except that:
Compression decreases overall contrast ratio, so
lighting extremes are not well tolerated
Shadows present additional quot;detailquot; that must be
preserved, which steals bandwidth from important
detail -- like subject’s faces -- and can degrade
quality


Overview
Lighting is the single most important
determinant of video quality
Low lighting causes gain (noise) in the video,
complicating compression
Hierarchy of considerations
Ensure lighting is adequate to produce clear,
easily compressible image
Then worry about style and mood


18

Know Your Lighting Styles

Three-point Flat
Useful for setting mood Visually neutral (e.g. boring)
Hard to set up Easy to set up
Heavy shadows tough to Easy to compress
compress


Which Lighting Style Should I Use?

Category Flat 3-Point

Traditional broadcast 14 0

Internet-only broadcast 9 5
Corporate informational 4 5
Corporate case study 4 5

Clearly can go either way
Origins of lighting
Set (or not set) mood
Model the face


19

3-Point Lighting Continuum
From subtle modeling
To “classy” look
To “artistic”
To “dramatic”
To going to far


3-Point Rules
Match lighting to
mood
Subtle modeling to
dramatic
Match lighting to
environment
Otherwise, lighting
may look contrived


20

The Net/Net on Lighting
No one ever got fired for using flat lighting
Easier to setup and compress, but can be boring
3-Point Variations
Subtle - to create modeling
Dramatic - to create mood
Good for case studies and interviews
Questionable for fact oriented business video
Best when lighting matches environment
Watch contrast ratio issues


Camera Positioning, Framing and
Settings

analog production
Framing for streaming
Safe zone
Framing on the ‘Net
Rule of thirds
Managing camera motion
Producing a soft background (bonus topic)
Progressive vs. interlaced

21

Camera Skills - What's
Different?
No safe zone
Positioning for a smaller window
Minimize camera motion
Shooting in progressive mode


How do I Frame for Streaming?
Title safe zone
Analog video has safe
zone
Outer 10-15% eliminated
as overscan
All pixels show in
streaming
So:
Can zoom in a bit tighter
b/c more room for other
content
OK for streaming, wouldn't be visible
on a TV set Copyright © 2007 Jan Ozer, All Rights Reserved

22

Framing for the Internet
Most streaming video produced at 320x240 -
480x360
Smaller viewing window, and no safe zone, so
you should frame more tightly
But, viewed from much closer to screen
But - don’t deviate from classic positioning*
Classic framing is what people expect
Don’t make what should be a medium shot
a close up just because it’s streaming

* How Low Can You Go, The Effect of low Resolutions on Shot Types in Mobile TV, Knoche, et al.


Framing on the Net

Extreme close-up, Edgy -
Medium Shot - Waist up -
“listen to me!”
Good for high res videos

Medium close-up, arm-pits
Up - Good all around shot


23

What’s the Rule of Thirds?

When facing the interviewer When facing the camera
Talking to someone else Talking to the viewer
Position in back third of the
frame, eyes at or near the top Position in the middle
1/3 Eyes at or near top 1/3
With quot;Look roomquot; in direction
they are facing


Managing Camera Motion
Camera - shooting techniques
Use a tripod
Avoid panning and zooming whenever possible. Cuts
are better
If possible, soften background (bonus topic)
Limit on-screen motion
Talent – consider sitting, and advise against excessive
motion


24

Should I Shoot Progressive?
What’s progressive (and why do I care?)
The short answer
Detailed findings (bonus)


Progressive vs. Interlaced
Most SD cameras capture interlaced video
60 fields per second, not 30 frames
Fields are captured 1/60th of a second apart
All streaming class codecs are frame based
Converting from fields to frames can cause a stair step
or Venetian blind artifacts which deinterlacing can
resolve
Progressive cameras shoot 30 fps and divide into fields
Fields match up perfectly for streaming production


25

Can’t Editors Deinterlace?
Yes, but artifacts linger


Should I Shoot Progressive?
Does progressive source produce better
streaming video than interlaced?
Ran serious of tests described in bonus materials
Short answer is yes - in all but the most controlled
environments


26

Conclusion - Real World

Better retention of fine detail
Eliminate/minimize the jaggies


Conclusions
Progressive delivers noticeably better quality
in all but the most controlled shoots
So:
If you're buying a camera for streaming, buy
progressive
If you have progressive, use it
If your camcorder doesn't have progressive, and
you shoot lots for streaming, consider new unit

Article here: http://www.nxtbook.com/nxtbooks/streamingmedia/0607/index.php

27

Production - Conclusion
Any Questions?


Editing/Pre-processing
Choosing your targets
Producing the correct output resolution and
aspect ratio
Deinterlacing
Noise reduction filtering
Workflow


28

What Output Parameters
Should I Use?
Codec
Resolution
Frame rate
Audio bit rate


About the Survey
Targets
Informal survey of 50+ web sites
Two categories, broadcast and corporate
Files chosen
Broadcast - most popular shows on the channel
Corporate - searched for “Flash Video,” “Windows
Media” and QuickTime to find video files
Chose newest, highest resolution streaming file


29

About the Survey
Broadcast (partial)
ABC, CBS, Fox, CNN, ESPN, The Golf Channel,
CNET, BusinessWeek, Forbes, Fortune, WSJ, NY
Times, SI, DL.TV
Corporate (partial)
Accenture, AMEX, Visa, IBM, E&Y, Chevron,
Cisco, EDS, Microsoft, HP, GE


Codec Selection, 4/’07 & 11/’07
11/07 11/07 11/07 4/07 4/07
Flash WMV Other Flash WMV
Broadcast
Broadcast – conservative 2 0 0 1 2
Broadcast – midrange 10 3 0 5 5

Broadcast – aggressive 4 0 0 2 1
Corporate
Corporate – conservative 5 6 0 4 5
Corporate - aggressive 4 3 0 1 4

What question does this slide answer?

30

Analysis
Broadcast channels almost all Flash
Notable WMV defectors (Weather Channel, Fox,
MSNBC (????) and CNN)
Windows Media still popular in corporate
For streaming:
Saw Real once (EDS, newer videos were Flash)
Saw QuickTime for streaming once (Accenture,
later videos all Windows Media)
iPod videos (of course) all QuickTime

What Resolution/Data Rate
Should I Use? (11/07 data)
Video Audio Bits/
Average Total Data Rate Data pixel/
Resolution Pixels (Kbps) Rate sec
Broadcast
Broadcast – conservative (2) 292x219 64,536 394 96 6.05
Broadcast – midrange (13) 446x322 141,191 432 62 3.08
Broadcast – aggressive (4) 604x349 211,641 519 104 2.46

Corporate
6.78/
Corporate – conservative (11) 322x238 76,800 502/313* 63 3.99 *
Corporate - aggressive (7) 477x319 155,765 424 55 2.92

* Corrected for two sites with off the charts data rates


31

What Resolution/Data Rate
Should I Use? (4/07 data)
Video Audio Bits/
Average Total Data Rate Data pixel/
Resolution Pixels (Kbps) Rate sec
Broadcast
Broadcast – conservative (3) 320x240 76,800 288 66 3.75
Broadcast – midrange (10) 443x307 136,552 396 52 2.94
Broadcast – aggressive (3) 597x408 244,736 455 56 1.87

Corporate
Corporate – conservative (9) 320x240 76,800 304 52 3.96
Corporate - aggressive (5) 432x324 141,120 331 32 2.36


Changes from April to
November

Total Video Data Bits/ pixel/
Pixels Rate (Kbps) sec

Broadcast +3% +15% +12%
Corporate +8% +15%* +4%*

* adjusted for AMEX and Visa


32

What Frame Rate?

Average Data Rate (Kbps) 15 fps 30 fps Difference

Broadcast - midrange (4/9) 376 457 21%
Corporate - conservative (3/4) 379 465 23%

Some (perceived) efficiency gained by encoding at 15 fps
Cost is smoothness, most evident in fast moving clips
Try 15 fps to save bandwidth, but assess quality and smoothness


How Much Audio?

Audio Bit Rate Flash Other Difference

Broadcast - midrange (10/3) 68 Kbps 39 Kbps -43%
Case study - conservative (5/6) 83 Kbps 47 Kbps -44%
Case study - aggressive (4/3) 68 Kbps 37 Kbps -45%

Key points:
39 kbps for midrange broadcast - is your WMA audio data
rate too high?
Allocate roughly twice as much to audio with Flash b/c MP3
is comparatively poor encoder


33

Switching to Flash
WMA MP3 Additional
Audio Bit Rate bitrate Bitrate Bitrate

Weather Channel 48 kbps 96 kbps 100%
MSNBC 32 kbps 96 kbps 100%
CNN 32 kbps 96 kbps 100%
GE 48 kbps 80 kbps 67%
Price Waterhouse 48 kbps 96 kbps 100%
Chevron 48 Kbps 96 kbps 100%

What question does this slide answer?


What Audio Configuration?
Research (based on 4/7 data)
Windows Media - only format that provides details
Used Windows Media Player and Sliq Media
Technologies WMSnoop
Two groups
Broadcast
High volume, both cost and quality conscious
Corporate
Lower volume, more quality conscious than cost


34

What Audio Configuration?
Bit Rate Samples Mono/ CBR/VBR
(kbps) kHz Stereo
Entertainment
BusinessWeek 20 44 kHz Mono CBR
CBS 48 44 kHz Stereo CBR
CNN 32 44 kHz Mono CBR
Sports Illustrated 32 44 kHz Mono CBR

Today Show 32 44 kHz Mono CBR
Weather Channel 48 44 kHz Stereo CBR
35 kbps 4M/2S All CBR
Corporate
Deloitte case study 64 44 kHz Stereo VBR
Accenture 96 48 kHz Stereo CBR
Microsoft 48 44 kHz Stereo VBR
HP 64 44 kHz Stereo CBR
68 kbps 4S 2/2


Audio Configuration - Analysis
Entertainment sites balance bandwidth costs
and quality
Consistently use mono/relatively low bitrates
Lower stream count corporate sites worry
primarily about quality
Consistently use stereo and higher bitrates
Stereo adds no value to speech or most
music, so mono is preferred
Some audio codecs (WMA) default to stereo


35

Conclusions?
Use mono for content that’s primarily speech
Use 16-bit in all cases
Consider 22 kHz for speech
CBR is OK for audio


How Do I Produce the Right
Aspect Ratio?
What's wrong with this picture?
Producing aspect ratio correct video (the
short answer)
Explanation (bonus)


36




Anderson Cooper
Digital Photo
Frame grab
from streaming file
(cnn.com)

37

Why Is This So Hard?
Different video formats have different “aspect
ratios” so are “stretched” for television display
4:3 DV - .9
16:9 DV - 1.2
HDV - 1.33
Computer display is all square pixel (1:1)


How Do I Get it Right?
Always output Square Pixel (1:1)
Irrespective of input PAR
When square not available, “distort”
You want to change aspect ratio from analog to square
Never choose “maintain aspect ratio” unless encoding
from square pixel source
Easiest (but not essential) when output
resolution matches display aspect ratio
4:3 - 640x480, 480x360, 400x300, 320x240
16:9 - 640x360, 480x270, 320x180


38

Getting it Right (4:3 DV Input)
Squeeze
Compressor

Flix Pro

Adobe Media Encoder Episode


Why “Distort?”

To change aspect ratio from this To this

39

How Do I Optimize
Deinterlacing Quality?
About deinterlacing
Why it's important
Rules of the game


What is Deinterlacing (Take 2)?
Most SD cameras capture interlaced video
60 fields per second, not 30 frames
Fields are captured 1/60th of a second apart
All streaming codecs are frame based
Converting from fields to frames can cause a
stair step or Venetian blind artifacts which
deinterlacing can resolve


40

Deinterlacing – Why it's Important


Deinterlacing - Rules of the Game
Always deinterlace
when producing with
interlaced input
Editors have different
controls, but you may
need to :
Select deinterlacing
(and technique), AND
Output a progressive Apple Compressor

file


41

Deinterlacing - Rules of the Game

Deinterlacing artifacts are easy to
spot; once seen and recognized,
you can resolve
Not all programs deinterlace equally
well


Maximizing Deinterlacing Quality
The best AlgoSuite (www.algolith.com), plug-in for
After Effects, Digital Fusion and Shake

Very, very Episode
good Compressor (Best setting)
Very good Premiere Pro/After Effects/Flash Video
Encoder 9
Compressor (Better setting)
On the bubble Squeeze, Flix Pro
Scale before Windows Media Encoder, QuickTime Pro,
encoding Flash 8 Encoder


42

Rating the Players


Conclusion
Plan workflow to maximize deinterlacing
quality
If encoding in tool that de-interlaces poorly, scale
and deinterlace in your editor
With trophy footage, pre-process after editing and
before compression


43

Does Noise Reduction Work?
Many encoders offer
noise reduction
features
Generally low quality
tools that blur entire
frame, potentially
losing detail
Good for witness
protection videos


Does Noise Reduction Work?
Best tools are usually third party (and
expensive)
Use adaptive techniques that distinguish between
noise and true motion
This reduces noise without blurring or other
artifacts
Generally worth a try when image is noisy
from chroma gain or poor quality source


44

AlgoSuite from Algolith
Concert shot with poor lighting
Some noise obvious from back camera
Trophy video, so worth the effort
Again - may have to modify workflow to apply best noise
reduction filter

Flash
1:45


Editing/Preprocessing -
Conclusion
Any questions?


45

Encoding
Terms and techniques
Working with MPEG-4/H.264/AVC
Landscape
iPod delivery
Working with Flash
Landscape
Encoding tools
Working with Windows Media Video
Landscape
Encoding tools


Terms and Techniques
Constant and variable bit rate encoding
Streaming vs. progressive download
Working with key frames


46

Constant vs Variable Bit Rate
800 kbps VBR

500 kbps CBR

300 kbps

Low Motion Moderate Motion Low Moderate High
Motion Motion Motion


Constant vs Variable Bit Rate
Constant Bit Rate (CBR)
One bit rate applied to entire video,
irrespective of content
Pros: Easy and fast
Cons: Doesn’t optimize quality
Variable Bit Rate (VBR)
Dynamic bit rate matches motion in video
Pros: Best quality
Cons: Slow, can produce erratic stream

47

When Should I Use VBR/CBR?
Consider VBR when:
Clips are longer than 60 seconds
Varied motion in clip (some action, some talking head)
Producing for progressive download
Not time constrained
Consider CBR when:
In a hurry (or live encoding)
Producing for streaming
Consistent motion (especially talking head)


How do I Produce the Best
Quality CBR?

Use 2-pass CBR
Scans file (like VBR), but packs data into a
consistent stream
Best of both worlds when available
1-pass of live or draft work

48

How Do I Produce the Optimal
VBR File?
2 passes or more
Use “Constrained”
Constrains to data rate
Set Target and Max/Min
Overall target
Max/Peak bit rate-
Rule of thumb is 1.5 - 2X
Minimum bit rate (not shown)
Useful when low motion video
suffers in quality
Rule of thumb is .5X unless lots
of very low motion


VBR, CBR and Delivery Mode - Streaming vs.
Progressive Download (Review)

Streaming
Distributed by quot;streaming serverquot;
Stream monitored and dished out as needed
Starts playing before fully downloaded
Stream pushed out as quickly as possible


49

VBR, CBR and Delivery Mode - Streaming vs.
Progressive Download (Review)

When producing for streaming
Determine if any unique requirements for server
Determine if any unique streaming related
features (multi-bit rate files)
Typically, use CBR for steady stream
When producing for progressive download
Determine if any unique features (fast-start)
Encode using VBR for best quality


Key Frames
Defined
Relevant controls
A note of caution
Key frame controls vary by codec and encoder
Controls in your program probably won't look like
those shown here
General principles should work similarly


50

What are I, B and P Frames?
I-Frame - encoded
without reference to
other frames (also
called Key Frames)

P - looks backward to I and P frames (predicted)
B - looks forward and backward to previous I and P
frames (Bi-directional interpolated)
No frames refer to B-Frame


What do I Need to Know About
Key Frames?
Key frames are needed for
interactivity
All playback starts on a key frame
When seeking to a random frame,
must start playback at key frame
Key frames help quot;resetquot; quality:
Useful at scene changes (quot;Naturalquot;
key frames)
Recommended:
Make sure quot;naturalquot; or equivalent is
enabled
Go with default duration (5-10
seconds)


51

What do I Need to Know About
B Frames?
Typically the most “efficient” frame
Hardest to decode with greatest
buffer requirements
Usually the key difference between
“simple” and “advanced” profiles in
MPEG and Windows Media codecs
In general:
Use B-Frames when producing for
computer playback
Don’t use when producing for device
playback (iPod, iPhone, etc.)
Interval is number of B frames
between I and P-Frames.
1-2 is recommended setting


Codec Specific Controls
H.264
Flash
Windows Media


52

What Do I Need to Know About
MPEG-4/H.264?
How is MPEG-4 different from H.264?
When should I use each?
Anything special about producing MPEG-
4/H.264?
How do I encode MPEG-4?
How do I encode H.264?
Which is the best H.264 Encoder?


How is MPEG-4 different from
AVC/H.264?

AVC is the MPEG-4
standard’s most
advanced codec
(MPEG-4 part 10)
AVC/H.264 are the
same
Highest current
evolution of MPEG-4
encoding
First standard adapted
by ISO and ITU
Supposedly about 50%
Streamcrest Associates more efficient than
http://www.streamcrest.com/SDF%20Final1.pdf MPEG-4

53

Should I use MPEG or H.264?
H.264 produces better
quality
Virtually all computers can
decode H.264 at this point
Use H.264 for computers
and devices that support
H.264 (note Apple presets)
Use MPEG-4 for other
devices or very old
computers


Anything Special About
Producing MPEG-4/H.264?
Quality varies by implementation
Apple is the best I’ve seen
Quality variance is less with other codecs
All Windows Media encoding performed via MS
code modules (DLLs)
All Flash VP6 encoding performed via On2 DLLs
So: Choose encoding tool wisely


54

What Else Do I Need to Know
about Producing H.264?
Customize for delivery
mode
Hinted streaming for
streaming server
Fast Start - Compressed
Header
Otherwise, must fully
download before playing
Not all encoding tools
support Fast Start
Adobe Media Encoder
most notable


What is an MP4 file (and how is
it different from MOV)?
H.264 file extensions
MPEG “wrapper” is QuickTime
based, so formats generally
interchangeable
QuickTime Player will play
.MP4 files as well as .MOV
Common extensions are .m4v
and .m4a, and .3GP
Extension Defaults
Most streaming files use MOV
Most files produced for devices
use .MP4 or derivative
Follow the preset and don’t
change unless you’re having
problems

55

How Do I Produce MPEG-4?

Know Your Profile
Simple Profile for low bit rate and low resolution applications
Advanced Simple Profile for best quality
Conclusion - use Advanced Simple for streaming (called
MPEG-4 Improved in QT Pro)
Unfortunately, presentation varies by application


How Do I Produce H.264/AVC?

Know Your Profile
Baseline Profile - For videoconferencing and mobile app
(No B-Frames);
Main Profile/Extended: Extended is preferred, use Main
when not available (both have B-frames)
High Profile: For broadcast, HD DVD and Blu-ray
All have multiple levels


56

H264 Comparisons


Which H.264 Encoder is Best?
Encoder Rating Comments
Compressor Very Good • The standard by which all others are judged

Adobe Media Lacks • No Fast Start option; No data rate control
Encoder features, for audio on streaming file; No CBR
quality fair streaming file or 2-pass CBR
• Very good low motion quality, blocky with
high motion
Episode Pro Fair to • Good in low motion
Poor • Falls apart in high motion
• Some fading

Squeeze Good •Soft appearance in low motion, some
fading, very crisp in high motion
ProCoder Good •Image got soft and blocky with motion


57

Flash?
Which codec should I use?
What do I need to know about producing
VP6?
What’s the best Flash Encoder?
What’s happening with H.264?


Which Codec Should I Use?
Codecs - Current
Sorenson Spark - only used now for compatibility with older
players
VP6 - introduced with Flash 8; two quality levels
One pass - good, but not best quality, especially for
challenging (high motion/low data rate) clips
Two pass - best for challenging footage
Audio - MP3
Flash Player 9
H.264/AAC playback support
MOV format support


58

Choosing a Flash Encoder
For maximum quality and flexibility you need:
Encoder with VP6
Encoder with 2-pass VBR
Encoder with quality scaling and deinterlacing
Other desirable features
Batch
Multiple format support


Survey of Flash Encoders

Tool Batch De-int VP6 2 Pass Price
Flash 8/9 Video Encoder Yes (F only) No/ Yes No free
Yes
CS3 Video Encoder Yes (F only) Yes Yes No free
Premiere Pro/After Effects No Yes Yes No free
Sorenson Squeeze Yes Yes Yes Yes $249
On2 Flix Pro Yes (F only) Yes Yes Yes $249
Episode Pro Yes Yes Yes Yes $995
Flix Exporter (apps below) Yes Yes Yes Yes $199
Rhozet Carbon Coder Yes Yes Yes Yes $4,995
Discreet Media Cleaner, Canopus Pro Coder (VP6 for Flash video only), QuickTime Pro, Adobe After Effects,
Apple Final Cut, and Apple Compressor


59

Which Flash Encoder is Best?
Compressor Very good • Need Flix Exporter,
• Quality identical to Flix Pro output

Adobe Media Fair •1-Pass CBR only, OK for draft and low
Encoder motion files
Episode Pro Very Good • Almost identical to Flix Pro
Squeeze Good • Noisy backgrounds
ProCoder Very Good • Needs On2 Flix Exporter, Quality very good
Flix Pro The Best • The standard by which all others are judged


Adobe Flash Announcement
Why H.264? Infrastructure/Ecosystem
Native graphics card support
Hardware based H.264 encode
Standard is widely adapted
AAC audio better quality than MP3
Will not support Alpha channel
When will it matter?
Flash has traditionally fast adoption cycle
Start considering now


60

Windows Media?
How do I get the latest codecs?
What’s VC-1 and how does it relate to WMV9?
What are the relevant Windows Media profiles (and
do I care)?
Which is the best WMV encoder?
How can I “tweak” Windows Media video files for
maximum quality?
What are Multiple Bitrate Files (and do I care)?
What’s Silverlight (and do I care)?


How Do I Get the Latest Codecs
Microsoft (quietly) released updated codecs
installed with either:
Media Player 11
The Windows Media Format SDK 11
(http://msdn2.microsoft.com/en-us/library/aa387410.aspx)
Does it matter?
Yes - codec quality has noticeably (if not
significantly) improved


61

What’s VC1 and How Does it Relate to
WMV9?
From the mouth of Ben Waggoner, MSFT
“VC-1 is SMPTE’s version of WMV 9. Windows Media
Video 9 is Microsoft's brand for our VC-1 implementation.”
“Basically, just think of “WMV 9” and “VC-1” in a WMV file
as synonymous.”

After installing WMF SDK 11
Windows Media Encoder still calls the codecs WMV 9

Silverlight Expression Encoder calls the same codecs VC-1

Both create WMV files


What are the Windows Media Profiles?

Now two profiles
Main - backwards compatible, no codec update required
Advanced Profile
Supports interlaced video (for VC1)
Not backwards compatible, codec update (not player
update) required
Problem for locked down corporate environments
Problem for off-line viewing
When should I consider Advanced Profile? (hold that
thought)


62

Windows Media Comparisons


Which WMV Encoder is Best?
Compressor Very good • Need Telestream Plug-in, quality very good

Adobe Media Very Good • Very close to Windows Media Encoder
Encoder
Episode Pro Poor • Fair quality low motion, drops lots of frames
in high motion and poor quality
Squeeze Very Good • Slightly better than Windows Media Encoder
ProCoder


63

How Can I Tweak WMV Files
for Maximum Quality?
Both profiles have advanced encoding
parameters that you can access:
Via command line
Manual registry changes
Registry changes via the “PowerToy” tool
Does tweaking improve quality?
Yes, in some well defined cases, but tough to find
a “one-size fits all video” tweak
Most effective when repeatedly producing similar
videos

What’s the PowerToy?


64

More on Tweaking
If you don’t tweak, the Main and Advanced
Profiles produce equivalent quality
Some critical tweaks are only supported in
the Advanced Profile, so if you’re going to
tweak, use the Advanced Profile


Tweaking Resources
Articles
My review of PowerToy and SDK 11
http://www.streamingmedia.com/r/printerfriendly.asp?id=9659
Ben Waggoner’s article on tweaking
http://www.streamingmedia.com/r/printerfriendly.asp?id=9456
Downloads
PowerToy - http://www.citizeninsomniac.com/WMV/
Windows Media Format SDK 11 http://msdn2.microsoft.com/en-
us/library/aa387410.aspx
Waggoner SME Presentation (page 24-42)
www.streamingmedia.com/east/SMEast2007-Waggoner-
Webcasting.pdf


65

Should I Produce Multiple Bitrate
Files?

What are they? Single video file with multiple
streams optimized for different connection speeds
Streaming server required
Server sends optimal stream for connection speed
Server monitors connection and adjusts stream if
packets are lost or frames dropped


Should I use MBR?
Mixed use in Broadcast sites (limited sample)

Yes No

CBS BusinessWeek
Weather Channel CNN
Sports Illustrated
Today Show


66

Usage Details from CBS

Stream 1 Stream 2 Stream 3
Video
Resolution 480x360 480x360 480x360
Frame rate 30 15 12
Data rate 570 kbps 281 kbps 127 kbps
Audio
Bitrate 32 kbps 20 kbps 16 kbps


Multiple Bitrate Analysis
Value of feature seems to have waned with
prevalence of broadband
No one cares about 56 kbps anymore
The success of Flash, which doesn’t offer MBR,
seems to indicate that it’s not a USP for WMV
Still, if you have the infrastructure, it’s a nice
convenience feature


67

What is Silverlight (and Do I
Care?)
What is Silverlight?
What are Silverlight’s limitations?
Should I consider using Silverlight?


What is Silverlight?
It’s a player
Cool, customizable player
Plays on Windows and Mac with relatively small
download
Same WMV 9 codecs at similar quality
It’s a platform
Richer design environment with vector-based
graphics, media, text, animation, and overlays
Flexible programming model that supports AJAX,
Microsoft Visual Basic .NET, C#, Python, and Ruby
and integrates with existing Web applications

• http://www.microsoft.com/silverlight/faq.aspx Copyright © 2007 Jan Ozer, All Rights Reserved

68

Silverlight Player

Chapter marks

Customizable
Skins

Player Controls
(hidden)

Captions

What are Silverlight’s Key
Limitations?
No Digital Rights Management
No multi-cast
No server side playlists
Limited support for multiple bitrate files


69

Should I consider Silverlight?
As a player? - Yes
Especially for casual producers of Windows
Media files, if you can live with the limitations
As a platform? Beyond the scope
As an encoding tool for Windows Media
Video files?
Expression Encoder can’t produce MBR files, but
very nice visual tool with excellent live features


How do I Try Silverlight?
Download Expression Encoder
Download Expression Blend 2 to customize
the player
Both at :
http://www.microsoft.com/expression/products/do
wnload.aspx?key=encoder


70

Questions?


Bonus Topics (time permitting)
Producing a soft background
Setting up 3-point and Flat lighting
Assessing exposure on the set
Interlaced vs. progressive details


71

Producing a Soft Background
Why?
Classy filmic look
Heightens attention
on subject
Makes video easier
to compress


Preliminaries
The larger the CCD, the easier
this is to do
Not all camcorders can do this
in all situations
Need largest aperture setting
possible (lowest f-stop)
Control exposure manually
Control lighting with ND filters,
higher shutter speed or by
moving light further from the
subject


72

Procedure
1. Subject max distance from
background
2. Camera max distance from
subject
3. Use zoom for framing
4. Open aperture to max
setting (lowest f-stop)


Setting up 3-Point Lighting
Key-major light source
Strongest light
45oangle from camera, pointing
down at 45o
Fill-moderates shadows
50% power of key light
45o angle from camera, pointing
down at 45o
Back light (or rim) creates
contrast with background
quot;hardquot; light
Shining down from back on
head and shoulders


73

Perfecting the Key Light
Positioning
Lateral - nose caret shouldn’t extend
beyond nose/mouth crease
Vertically - shouldn’t extend into lips
Watch shadows beneath chin
Lower lights to minimize or use
reflector
Watch for hot spots on face
Watch for shadow behind
subject
If not facing camera, place key
light opposite camera


Perfecting the Fill Light

Karma
Shouldn’t appear as separate light, but should
minimize key light
Laterally - start 90 degrees opposite key, then adjust to
taste
Toggle on/off to ensure no hotspots


74

Perfecting the Back Light

All about contrast
Make sure stand/cords not in frame
Turn off key/fill to make sure back light isn’t creating
hot spots on the face
Check whether it shines on the background (OK if
that’s what you want)


Producing Flat Lighting

Two approaches
Dual Key
Single Key
Both use back light


75

Flat Lighting - Dual Key

Two keys and a back light Setup issues:
Typically, 2 soft lights No shadows on face
45o angle from camera, Minimize chin/nose shadows
pointing down at 45o
Watch location of back shadows
Back light-create contrast
Typical back light issues
Shining down from back on
head and shoulders

Flat Lighting - Single Key

Single key above the camera Key setup issues:
Typically, a soft light
No hotspots on face
As low as talent can stand it (to
minimize chin/nose shadows) Watch chin and nose
Back light-create contrast shadows
Shining down from back on Watch back shadows
head and shoulders Typical back light issues


76

Assessing Exposure at the Shoot
Rule #1: Some sets (with too much contrast) are
challenging to light for DV - get the set right first
Rule #2: It's better to be under exposed than over
exposed
Rule #3: Zebra stripes are your best friend
Rule #4: Scopes are your other best friend
Rule #5: When in doubt, check auto


Better to be Under than Over
If overexposed, detail is lost forever
If underexposed, can boost brightness in post and
improve the result
Key point: make sure quot;gainquot; is disabled in the
camera
Gain creates quot;noisequot; that becomes exaggerated when
video is brightened
If underexposed and gain is enabled, quality suffers
noticeably


77

Waveform and IRE Levels
100 IRE

7.5 IRE

Brightness measured on Waveforms shows levels of
IRE scale sections of frame
0 or 7.5 - black White shirt - 100
100 - white Her face - 75-80
This is broadcast quot;legalquot;


Zebras are Your Friend
F1.7 F2.4 F2.8

Zebra stripes show areas that exceed 100 IRE
Above that, detail is lost
Adjust iris (f-stop) until zebra stripes are almost all gone
What about the face?


78

More on Zebras
Generally configurable
Either 70/100 (VX2000)
Totally configurable
Common settings
100 - pure white
95 - white with a safe zone
70-80 - Caucasian face


3 Ways for On-Site YC Waveform

External Waveform Monitor ($1,000 - $4,000)
Adobe On Location on a notebook or desktop (shown)
Your video editor on a notebook or desktop
Capture video and apply monitor
Image from previous page from Premiere Pro


79

When in Doubt, Check Auto
Shoot using manual controls over gain,
shutter speed and iris for reasons discussed
Once you've reached optimal settings
Switch into automatic mode
Investigate significant differences
Caution
Auto lights the entire frame, you care primarily
about the face


Interlaced vs. Progressive
Testing


80

Progressive vs. Interlaced
Overview
The big questions
Test description
Scenarios
Conclusion


Overview - Theory
Traditional camcorders are
interlaced (shoot in fields, 1/60
of a second apart)
Streaming media is FRAME
based
To produce streaming video
from interlaced source requires
that you combine two fields


81

Overview - Theory
Shooting in progressive
mode eliminates that
problem and is vastly
superior to interlaced
But!
Most editors/compression
programs have
deinterlacing filters that
take you frame here:
To here.


The Big Questions
Does a progressive camcorder deliver better quality than
interlaced?
If so, how much?
If so, when does it matter most?
Implications:
If you're buying new, should you buy a progressive unit?
If your camcorder is interlaced, should you buy a new one for
streaming?
If your camcorder has progressive and interlaced, which mode
should you use?


82

Test Description
Shoot same scenes with two cameras
simultaneously
One progressive - Canon XH A1
One interlaced - Sony HDR-FX1
Scenes
High speed sports
Low contrast talking head
Real world (uncontrolled) shoot


Conclusions - Sports
Even at
relatively slow
shutter speeds
(like 60)
If you have
sharp edges,
you have a
problem


83

Conclusion - Talking Head

In those instances where:
Minimum sharp detail
Relatively slow shutter (like 60)
Not much distinguishable difference


Conclusion - Talking Head

Even when there's moderation motion


84

Conclusion - Real World

If you can't control the detail in the scene, go
progressive


Conclusions
Progressive delivers noticeably better quality in all
but the most controlled shoots
Especially with
Sharp edges, high motion and fast shutter speed
So:
If you're buying for streaming, buy progressive
If you have progressive, use it
If your camcorder doesn't have progressive, and you shoot
lots of streaming, consider new unit


85

Video Production for Streaming

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