Motion interpolation

Motion interpolation is a form of video processing in which intermediate animation frames are generated between existing ones, in an attempt to make animation more fluid.

Applications

HDTV

Motion interpolation is used in various display devices such as HDTVs and video players, aimed at alleviating the video artifacts introduced by framerate conversions in fixed-framerate displays such as LCD TVs. Films are recorded at a frame rate of 24 frames per second (frame/s) and television is typically filmed at 25, 50, 30 or 60 frames per second (the first two being PAL, the other two from NTSC). Normally, when a fixed framerate display such as an LCD screen is used to display a video source whose framerate is less than that of the screen, frames are often simply duplicated as necessary until the timing of the video is matched to that of the screen, which introduces a visual artifact known as judder, perceived as "jumpiness" in the picture. Motion interpolation intends to remedy this by generating intermediate frames that make animation more fluid.

While common, not all 120 Hz HDTVs include a motion interpolation feature. Also, anti judder technology is not the same as motion blur reducing technology, but is frequently lumped together with it.^[1]

The commercial name given to motion interpolation technology varies across manufacturers, as does its implementation.

• Hitachi - Reel120^[2]
• Insignia - DCM Plus, for Digital Clear Motion 120 Hz
• Kogan Technologies - MotionMax 100Hz^[3], 200 Hz
• LG - TruMotion 120 Hz, 240 Hz, 480 Hz
• AOC - Motion Boost 120 Hz
• Mitsubishi - Smooth 120 Hz
• Panasonic - Intelligent Frame Creation (IFC)
• Philips - HD Digital Natural Motion^[4]
• Samsung - Auto Motion Plus 120 Hz^[5], 240 Hz
• Sharp - Fine Motion Enhanced^[6], AquoMotion 240Hz^[7]
• Sony - MotionFlow 100 Hz, 100 Hz PRO (XBR series, Australia), 120 Hz, 200 Hz, 240 Hz, 400 Hz.^[8][9]
• Toshiba - ClearScan 120 Hz, 240 Hz
• Vizio - MEMC (Motion Estimation, Motion Compensation)^[10]
• Sceptre - MEMC (Motion Estimation/Motion Compensation)

Side effects

A few side effects can be introduced by the use of the technology.

Visual Artifacts

Motion interpolation on certain brands of HDTVs is sometimes accompanied by visual anomalies in the picture, described by CNET's David Carnoy as a 'little tear or glitch' in the picture, appearing for a fraction of a second. He adds the effect is most noticeable when the technology suddenly kicks in during a fast camera pan.^[1]

Soap Opera Effect

The "video" look is a byproduct of the perceived increase in framerate due to the interpolation and is commonly referred to as the "Soap Opera Effect" after the way those shows looked, having been shot on cheaper 60 Hz video instead of regular broadcast equipment or film.^[11] Not everyone likes the effect and some complain that it ruins the cinematic look of home movies. ^[10] For this reason, almost all manufactuers have built in an option to turn the feature off. The soap opera effect can also be known as 'Jutter adjustment' or 'Jutter Removal' ^[12] This "video look" is created deliberately by the VidFIRE technique to restore archive television programs that only survive as film telerecordings.^[13]

PC video players

WinDVD uses Philips' TrimensionDNM for frame interpolation.^[14]

CrystalPlayer uses Motion Morphing MultiSampling for frame interpolation.^[15]

PowerDVD uses TrueTheater Motion for interpolation of DVD and video files to up to 72 frame/s.^[16]

Splash PRO uses Mirillis Motion² technology for up to Full HD video interpolation.^[17]

See also

• HDTV blur
• Unsharp mask
• Television standards conversion
• VidFIRE
• Motion compensation

References

1. ^ ^{a b} Carnoy, David (October 25, 2007). "Six things you need to know about 120 Hz LCD TVs". CNET.com. http://reviews.cnet.com/4520-6449_7-6792632-1.html. Retrieved 2008-02-02. 
2. ^ Hitachi to Unveil New Line of Ultra Thin LCDs at CES
3. ^ Kogan MotionMax 100Hz TVs
4. ^ Trimension
5. ^ Samsung LN40C650 40" 1080p LCD TV- NEW
6. ^ Sharp intros slate of new AQUOS LCD HDTVs
7. ^ [1]
8. ^ SONY UNVEILS FIRST BRAVIA FLAT-PANEL LCD HDTVs WITH INTERNET VIDEO LINK COMPATIBILITY
9. ^ Sony's site for explaining Motionflow 200Hz using the world's largest zoetrope and Kaká
10. ^ ^{a b} Moskovciak, Matthew (January 8, 2008). "Vizio adds 120 Hz LCDs to its lineup". CNET.com. http://ces.cnet.com/8301-13855_1-9845306-67.html. Retrieved 2008-02-01. 
11. ^ Biggs, John (August 12, 2009). "Help Key: Why 120Hz looks “weird”". crunchgear.com. http://www.crunchgear.com/2009/08/12/help-key-why-hd-video-looks-weird. Retrieved 2009-11-13. 
12. ^ "What is the Soap Opera Effect?". Techtarget.com. http://whatis.techtarget.com/definition/soap-opera-effect.html. Retrieved 2011-04-20. 
13. ^ "VIDFIRE - The Doctor Who Restoration Team". restoration-team.co.uk/. http://www.purpleville.pwp.blueyonder.co.uk/rtwebsite/vidfire.htm. Retrieved 2011-05-19. 
14. ^ Intervideo WinDVD 8 Platinum
15. ^ Crystal Reality - ultimate video and multimedia solutions for PC, Symbian and PocketPC platforms
16. ^ "Video Enhancement - TrueTheater Technology". CyberLink. http://www.cyberlink.com/stat/technology/enu/true-theater-solution.jsp. Retrieved 2009-08-24. 
17. ^ Mirillis Motion² technology