Producing Video
              for the Web

                                       Jan Ozer
                               ...
The Streaming Environment
 Concepts
   Bandwidth
   Delivery modes
   Resolution
   Data rate
 How streaming is different ...
What are My Delivery Options?
 Streaming
   Viewer clicks, video quickly starts to play
   Plays without interruption unti...
Why is Resolution Important?
 Most video starts life at 720x480 or higher
 Most video is scaled down for streaming
   320x...
How is Streaming Different?
     When truly streaming (not progressive
     download or download and play)
     Typically ...
What’s this Mean?
 At 1-1.5 mbps (640x480), most video looks fine
 without special care
 As data rates decrease, have to:
...
Producing for Max Streaming
Quality
 Production
  Setting the scene
    Choosing a background
    Clothing
  Lighting
  Ca...
Background - What's Different?
 Contrast issues:
   Very similar between analog and streaming -
   need to separate subjec...
Contrast
 Good contrast                  Bad contrast
   Deloitte - dark grey suit,     P&G - blue/blue
   light blue back...
Avoid Color/Contrast Extremes

 Brightness extremes hard for
 camera/codecs to preserve
 Color extremes make it tough to
 ...
Avoid Motion
 Akamai
 NAB




                                     Copyright © 2007 Jan Ozer, All Rights Reserved




Avoi...
Avoid Highly Saturated Colors

 DON'T use highly
 saturated colors – Which
 tend to create motion in
 the background
 DO -...
Creating the Perfect In-House
Background
 Simple is better
   Flat black works well
   MS got fancy and
   lost contrast
 ...
Building the Perfect
Background - On Location
 Need “on location” feel
   Curtains and portable backdrops out
 How to crea...
Background Checklist
 Does the background provide contrast with subject's face,
 clothing and hair?
 Are there extremes in...
Clothing - What's Different?
 Must be more sensitive to detail that can
 produce compression artifacts (jewelry,
 glasses,...
Clothing Checklist
 Clothing
   Solid colors - dark blues, grays or browns
   Avoid white and light blue (which looks like...
Lighting - What's Different?
 Overall, analog and streaming are similar,
 except that:
   Compression decreases overall co...
Know Your Lighting Styles




 Three-point                 Flat
   Useful for setting mood      Visually neutral (e.g. bor...
3-Point Lighting Continuum
 From subtle modeling
 To “classy” look
 To “artistic”
 To “dramatic”
 To going to far




    ...
The Net/Net on Lighting
 No one ever got fired for using flat lighting
   Easier to setup and compress, but can be boring
...
Camera Skills - What's
Different?
 No safe zone
 Positioning for a smaller window
 Minimize camera motion
 Shooting in pro...
Framing for the Internet
     Most streaming video produced at 320x240 -
     480x360
       Smaller viewing window, and n...
What’s the Rule of Thirds?




When facing the interviewer         When facing the camera
   Talking to someone else      ...
Should I Shoot Progressive?
 What’s progressive (and why do I care?)
 The short answer
 Detailed findings (bonus)




    ...
Can’t Editors Deinterlace?
 Yes, but artifacts linger




                                      Copyright © 2007 Jan Ozer,...
Conclusion - Real World




    Better retention of fine detail
    Eliminate/minimize the jaggies


                     ...
Production - Conclusion
 Any Questions?




                                Copyright © 2007 Jan Ozer, All Rights Reserved...
What Output Parameters
Should I Use?
 Codec
 Resolution
 Frame rate
 Audio bit rate




                                  ...
About the Survey
   Broadcast (partial)
       ABC, CBS, Fox, CNN, ESPN, The Golf Channel,
       CNET, BusinessWeek, Forb...
Analysis
    Broadcast channels almost all Flash
        Notable WMV defectors (Weather Channel, Fox,
        MSNBC (????)...
What Resolution/Data Rate
Should I Use? (4/07 data)
                                                          Video       ...
What Frame Rate?

Average Data Rate (Kbps)                   15 fps     30 fps       Difference


Broadcast - midrange (4/...
Switching to Flash
                              WMA         MP3            Additional
   Audio Bit Rate             bitra...
What Audio Configuration?
                           Bit Rate   Samples   Mono/    CBR/VBR
                           (kbp...
Conclusions?
 Use mono for content that’s primarily speech
 Use 16-bit in all cases
 Consider 22 kHz for speech
 CBR is OK...
What's wrong with this picture?




                               Copyright © 2007 Jan Ozer, All Rights Reserved




What...
Why Is This So Hard?
 Different video formats have different “aspect
 ratios” so are “stretched” for television display
  ...
Getting it Right (4:3 DV Input)
                                        Squeeze
    Compressor




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




                 ...
Deinterlacing – Why it's Important




                              Copyright © 2007 Jan Ozer, All Rights Reserved




De...
Deinterlacing - Rules of the Game

 Deinterlacing artifacts are easy to
 spot; once seen and recognized,
 you can resolve
...
Rating the Players




                                      Copyright © 2007 Jan Ozer, All Rights Reserved




Conclusion...
Does Noise Reduction Work?
 Many encoders offer
 noise reduction
 features
   Generally low quality
   tools that blur ent...
AlgoSuite from Algolith
 Concert shot with poor lighting
   Some noise obvious from back camera
   Trophy video, so worth ...
Encoding
 Terms and techniques
 Working with MPEG-4/H.264/AVC
   Landscape
   iPod delivery
 Working with Flash
   Landsca...
Constant vs Variable Bit Rate
800 kbps                                                                                    ...
When Should I Use VBR/CBR?
 Consider VBR when:
   Clips are longer than 60 seconds
   Varied motion in clip (some action, ...
How Do I Produce the Optimal
VBR File?
  2 passes or more
  Use “Constrained”
    Constrains to data rate
  Set Target and...
VBR, CBR and Delivery Mode - Streaming vs.
Progressive Download (Review)

  When producing for streaming
    Determine if ...
What are I, B and P Frames?
I-Frame - encoded
without reference to
other frames (also
called Key Frames)



P - looks back...
What do I Need to Know About
B Frames?
 Typically the most “efficient” frame
 Hardest to decode with greatest
 buffer requ...
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 spe...
Should I use MPEG or H.264?
 H.264 produces better
 quality
 Virtually all computers can
 decode H.264 at this point
 Use ...
What Else Do I Need to Know
about Producing H.264?
 Customize for delivery
 mode
   Hinted streaming for
   streaming serv...
How Do I Produce MPEG-4?




 Know Your Profile
   Simple Profile for low bit rate and low resolution applications
   Adva...
H264 Comparisons




                                                      Copyright © 2007 Jan Ozer, All Rights Reserved
...
What Do I Need to Know About
Flash?
 Which codec should I use?
 What do I need to know about producing
 VP6?
 What’s the b...
Choosing a Flash Encoder
    For maximum quality and flexibility you need:
         Encoder with VP6
         Encoder with...
Which Flash Encoder is Best?
Encoder        Rating                         Comments
Compressor    Very good   • Need Flix ...
What Do I Need to Know About
Windows Media?
 How do I get the latest codecs?
 What’s VC-1 and how does it relate to WMV9?
...
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. Win...
Windows Media Comparisons




                                                  Copyright © 2007 Jan Ozer, All Rights Rese...
How Can I Tweak WMV Files
for Maximum Quality?
 Both profiles have advanced encoding
 parameters that you can access:
   V...
More on Tweaking
 If you don’t tweak, the Main and Advanced
 Profiles produce equivalent quality
 Some critical tweaks are...
Should I Produce Multiple Bitrate
Files?




 What are they? Single video file with multiple
 streams optimized for differ...
Usage Details from CBS

                Stream 1    Stream 2             Stream 3
     Video
 Resolution     480x360     4...
What is Silverlight (and Do I
Care?)
    What is Silverlight?
    What are Silverlight’s limitations?
    Should I conside...
Silverlight Player


Chapter marks


                                                         Customizable
               ...
Should I consider Silverlight?
 As a player? - Yes
   Especially for casual producers of Windows
   Media files, if you ca...
Questions?




                                 Copyright © 2007 Jan Ozer, All Rights Reserved




Bonus Topics (time perm...
Producing a Soft Background
 Why?
    Classy filmic look
    Heightens attention
    on subject
    Makes video easier
   ...
Producing a Soft Background
Procedure
  1.    Subject max distance from
        background
  2.    Camera max distance fro...
Perfecting the Key Light
 Positioning
   Lateral - nose caret shouldn’t extend
   beyond nose/mouth crease
   Vertically -...
Perfecting the Back Light




    All about contrast
    Make sure stand/cords not in frame
    Turn off key/fill to make ...
Flat Lighting - Dual Key




   Two keys and a back light               Setup issues:
       Typically, 2 soft lights     ...
Assessing Exposure at the Shoot
 Rule #1: Some sets (with too much contrast) are
 challenging to light for DV - get the se...
Waveform and IRE Levels
100 IRE




7.5 IRE




          Brightness measured on              Waveforms shows levels of
  ...
More on Zebras
 Generally configurable
   Either 70/100 (VX2000)
   Totally configurable
 Common settings
   100 - pure wh...
When in Doubt, Check Auto
 Shoot using manual controls over gain,
 shutter speed and iris for reasons discussed
 Once you'...
Progressive vs. Interlaced
 Overview
 The big questions
 Test description
 Scenarios
 Conclusion




                     ...
Overview - Theory
 Shooting in progressive
 mode eliminates that
 problem and is vastly
 superior to interlaced
 But!
    ...
Test Description
 Shoot same scenes with two cameras
 simultaneously
   One progressive - Canon XH A1
   One interlaced - ...
Conclusion - Talking Head




 In those instances where:
   Minimum sharp detail
   Relatively slow shutter (like 60)
 Not...
Conclusion - Real World




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


                             ...
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Video Production for Streaming

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Video Production for Streaming

  1. 1. 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
  2. 2. The Streaming Environment Concepts Bandwidth Delivery modes Resolution Data rate How streaming is different from analog Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 2
  3. 3. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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) Progressive download Don’t have to compress to effective bandwidth, which may mean higher quality But, user may have to wait (e.g. QuickTime movie trailers) Copyright © 2007 Jan Ozer, All Rights Reserved 3
  4. 4. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 4
  5. 5. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 5
  6. 6. 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 Copyright © 2007 Jan Ozer, All Rights Reserved Streaming Environment - Conclusion Questions? Copyright © 2007 Jan Ozer, All Rights Reserved 6
  7. 7. Producing for Max Streaming Quality Production Setting the scene Choosing a background Clothing Lighting Camera positioning, framing and motion Optimizing camera controls Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 7
  8. 8. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 8
  9. 9. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 9
  10. 10. Avoid Color/Contrast Extremes Brightness extremes hard for camera/codecs to preserve Color extremes make it tough to maintain contrast Copyright © 2007 Jan Ozer, All Rights Reserved Avoid Color/Contrast Extremes Copyright © 2007 Jan Ozer, All Rights Reserved 10
  11. 11. Avoid Motion Akamai NAB Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 11
  12. 12. Avoid Highly Saturated Colors DON'T use highly saturated colors – Which tend to create motion in the background DO - Use more muted colors Copyright © 2007 Jan Ozer, All Rights Reserved Avoid Fine Patterns DON'T - use backgrounds with fine patterns and/or decorative lighting. DO - use a simple background with little visible detail Copyright © 2007 Jan Ozer, All Rights Reserved 12
  13. 13. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 13
  14. 14. Building the Perfect Background - On Location Need “on location” feel Curtains and portable backdrops out How to create compressible set? Copyright © 2007 Jan Ozer, All Rights Reserved Building the Perfect 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 Copyright © 2007 Jan Ozer, All Rights Reserved 14
  15. 15. 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? Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 15
  16. 16. 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) Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 16
  17. 17. 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 Copyright © 2007 Jan Ozer, All Rights Reserved How do I Light for Max Quality? What’s different between streaming and analog production Overview Decision time - flat lighting or shadows Producing three-point lighting (bonus) Producing flat lighting (bonus) Copyright © 2007 Jan Ozer, All Rights Reserved 17
  18. 18. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 18
  19. 19. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 19
  20. 20. 3-Point Lighting Continuum From subtle modeling To “classy” look To “artistic” To “dramatic” To going to far Copyright © 2007 Jan Ozer, All Rights Reserved 3-Point Rules Match lighting to mood Subtle modeling to dramatic Match lighting to environment Otherwise, lighting may look contrived Copyright © 2007 Jan Ozer, All Rights Reserved 20
  21. 21. 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 Copyright © 2007 Jan Ozer, All Rights Reserved Camera Positioning, Framing and Settings What’s different between streaming and 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 Copyright © 2007 Jan Ozer, All Rights Reserved 21
  22. 22. Camera Skills - What's Different? No safe zone Positioning for a smaller window Minimize camera motion Shooting in progressive mode Copyright © 2007 Jan Ozer, All Rights Reserved 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
  23. 23. 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. Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 23
  24. 24. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 24
  25. 25. Should I Shoot Progressive? What’s progressive (and why do I care?) The short answer Detailed findings (bonus) Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 25
  26. 26. Can’t Editors Deinterlace? Yes, but artifacts linger Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 26
  27. 27. Conclusion - Real World Better retention of fine detail Eliminate/minimize the jaggies Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 27
  28. 28. Production - Conclusion Any Questions? Copyright © 2007 Jan Ozer, All Rights Reserved Editing/Pre-processing Choosing your targets Producing the correct output resolution and aspect ratio Deinterlacing Noise reduction filtering Workflow Copyright © 2007 Jan Ozer, All Rights Reserved 28
  29. 29. What Output Parameters Should I Use? Codec Resolution Frame rate Audio bit rate Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 29
  30. 30. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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? Copyright © 2007 Jan Ozer, All Rights Reserved 30
  31. 31. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 31
  32. 32. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 32
  33. 33. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 33
  34. 34. 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? Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 34
  35. 35. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 35
  36. 36. 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 Copyright © 2007 Jan Ozer, All Rights Reserved How Do I Produce the Right Aspect Ratio? What's wrong with this picture? Producing aspect ratio correct video (the short answer) Explanation (bonus) Copyright © 2007 Jan Ozer, All Rights Reserved 36
  37. 37. What's wrong with this picture? Copyright © 2007 Jan Ozer, All Rights Reserved What's wrong with this picture? Anderson Cooper Digital Photo Frame grab from streaming file (cnn.com) Copyright © 2007 Jan Ozer, All Rights Reserved 37
  38. 38. 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) Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 38
  39. 39. Getting it Right (4:3 DV Input) Squeeze Compressor Flix Pro Adobe Media Encoder Episode Copyright © 2007 Jan Ozer, All Rights Reserved Why “Distort?” To change aspect ratio from this To this Copyright © 2007 Jan Ozer, All Rights Reserved 39
  40. 40. How Do I Optimize Deinterlacing Quality? About deinterlacing Why it's important Rules of the game Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 40
  41. 41. Deinterlacing – Why it's Important Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 41
  42. 42. Deinterlacing - Rules of the Game Deinterlacing artifacts are easy to spot; once seen and recognized, you can resolve Not all programs deinterlace equally well Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 42
  43. 43. Rating the Players Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 43
  44. 44. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 44
  45. 45. 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 Copyright © 2007 Jan Ozer, All Rights Reserved Editing/Preprocessing - Conclusion Any questions? Copyright © 2007 Jan Ozer, All Rights Reserved 45
  46. 46. 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 Copyright © 2007 Jan Ozer, All Rights Reserved Terms and Techniques Constant and variable bit rate encoding Streaming vs. progressive download Working with key frames Copyright © 2007 Jan Ozer, All Rights Reserved 46
  47. 47. Constant vs Variable Bit Rate 800 kbps VBR 500 kbps CBR 300 kbps Low Motion Moderate Motion Low Moderate High Motion Motion Motion Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 47
  48. 48. 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) Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 48
  49. 49. 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 Copyright © 2007 Jan Ozer, All Rights Reserved VBR, CBR and Delivery Mode - Streaming vs. Progressive Download (Review) Streaming Distributed by quot;streaming serverquot; Stream monitored and dished out as needed Progressive download Starts playing before fully downloaded Stream pushed out as quickly as possible Copyright © 2007 Jan Ozer, All Rights Reserved 49
  50. 50. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 50
  51. 51. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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) Copyright © 2007 Jan Ozer, All Rights Reserved 51
  52. 52. 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 Copyright © 2007 Jan Ozer, All Rights Reserved Codec Specific Controls H.264 Flash Windows Media Copyright © 2007 Jan Ozer, All Rights Reserved 52
  53. 53. 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? Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 53
  54. 54. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 54
  55. 55. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 55
  56. 56. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 56
  57. 57. H264 Comparisons Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 57
  58. 58. What Do I Need to Know About 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? Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 58
  59. 59. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 59
  60. 60. Which Flash Encoder is Best? Encoder Rating Comments 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 60
  61. 61. What Do I Need to Know About 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)? Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 61
  62. 62. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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) Copyright © 2007 Jan Ozer, All Rights Reserved 62
  63. 63. Windows Media Comparisons Copyright © 2007 Jan Ozer, All Rights Reserved Which WMV Encoder is Best? Encoder Rating Comments 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 Copyright © 2007 Jan Ozer, All Rights Reserved 63
  64. 64. 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 Copyright © 2007 Jan Ozer, All Rights Reserved What’s the PowerToy? Copyright © 2007 Jan Ozer, All Rights Reserved 64
  65. 65. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 65
  66. 66. 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 Copyright © 2007 Jan Ozer, All Rights Reserved Should I use MBR? Mixed use in Broadcast sites (limited sample) Yes No CBS BusinessWeek Weather Channel CNN Sports Illustrated Today Show Copyright © 2007 Jan Ozer, All Rights Reserved 66
  67. 67. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 67
  68. 68. What is Silverlight (and Do I Care?) What is Silverlight? What are Silverlight’s limitations? Should I consider using Silverlight? Copyright © 2007 Jan Ozer, All Rights Reserved 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
  69. 69. Silverlight Player Chapter marks Customizable Skins Player Controls (hidden) Captions Copyright © 2007 Jan Ozer, All Rights Reserved What are Silverlight’s Key Limitations? No Digital Rights Management No multi-cast No server side playlists Limited support for multiple bitrate files Copyright © 2007 Jan Ozer, All Rights Reserved 69
  70. 70. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 70
  71. 71. Questions? Copyright © 2007 Jan Ozer, All Rights Reserved Bonus Topics (time permitting) Producing a soft background Setting up 3-point and Flat lighting Assessing exposure on the set Interlaced vs. progressive details Copyright © 2007 Jan Ozer, All Rights Reserved 71
  72. 72. Producing a Soft Background Why? Classy filmic look Heightens attention on subject Makes video easier to compress Copyright © 2007 Jan Ozer, All Rights Reserved Producing a Soft Background 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 Copyright © 2007 Jan Ozer, All Rights Reserved 72
  73. 73. Producing a Soft Background 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) Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 73
  74. 74. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 74
  75. 75. 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) Copyright © 2007 Jan Ozer, All Rights Reserved Producing Flat Lighting Two approaches Dual Key Single Key Both use back light Copyright © 2007 Jan Ozer, All Rights Reserved 75
  76. 76. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 76
  77. 77. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 77
  78. 78. 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; Copyright © 2007 Jan Ozer, All Rights Reserved 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? Copyright © 2007 Jan Ozer, All Rights Reserved 78
  79. 79. 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 Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 79
  80. 80. 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 Copyright © 2007 Jan Ozer, All Rights Reserved Interlaced vs. Progressive Testing Copyright © 2007 Jan Ozer, All Rights Reserved 80
  81. 81. Progressive vs. Interlaced Overview The big questions Test description Scenarios Conclusion Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 81
  82. 82. 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. Copyright © 2007 Jan Ozer, All Rights Reserved 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? Copyright © 2007 Jan Ozer, All Rights Reserved 82
  83. 83. 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 Copyright © 2007 Jan Ozer, All Rights Reserved Conclusions - Sports Even at relatively slow shutter speeds (like 60) If you have sharp edges, you have a problem Copyright © 2007 Jan Ozer, All Rights Reserved 83
  84. 84. Conclusion - Talking Head In those instances where: Minimum sharp detail Relatively slow shutter (like 60) Not much distinguishable difference Copyright © 2007 Jan Ozer, All Rights Reserved Conclusion - Talking Head Even when there's moderation motion Copyright © 2007 Jan Ozer, All Rights Reserved 84
  85. 85. Conclusion - Real World If you can't control the detail in the scene, go progressive Copyright © 2007 Jan Ozer, All Rights Reserved 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 Copyright © 2007 Jan Ozer, All Rights Reserved 85

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