Is Frame Interpolation Important?

Evan Powell, January 20, 2009

In the past four months we've seen several new 1080p projectors released with a feature known generically as frame interpolation. The new Epson 7500UB and 6500UB have it, as does the Sanyo Z3000 and the Panasonic AE3000. Epson calls it FineFrame, Sanyo calls it Smooth Motion, and Panasonic calls it Frame Creation. But it is all the same concept: the projector evaluates the differences between individual frames of film or video, and creates interim frames to be inserted between the real frames in the source. The objective is to reduce motion judder and provide a cleaner, more artifact-free viewing of film and video material.

Two complaints have been circulating about frame interpolation technology. One is that it can make a movie look more like digital video, something which people are calling, somewhat derisively, the Soap Opera effect. In essence, the complaint is that it makes a film, which has a slightly surreal and sensual quality, look like a CNN Situation Room HD broadcast, which by comparison is hard, cold, clear, and real (sometimes disturbingly real). When James Bond begins to look like Wolf Blitzer, you know you have a problem.

The second complaint is that, while frame interpolation can reduce or eliminate much of the film judder we see in movies, it sometimes introduces other artifacts which may be just as problematic. For example, instead of the judder, we may see some ghosting as subjects move across the screen, or some unnatural disintegration of the picture during momentary fast pans of the camera.

These complaints are well-founded. Some frame interpolation systems do indeed produce these undesirable side effects. But if it is done well, the picture can be virtually free of artifacts while it retains that mystical film quality. Ideally, what you will see is a clean, stable, but still filmlike image that many will find irresistibly engaging.

Not All Frame Interpolation Systems are Created Equal

We've said this before and we cannot emphasize it enough: Don't make the mistake of seeing a frame interpolation demo on a particular video product and assume you've seen what it will look like on all video systems. Each vendor approaches it differently. They use different algorithms to generate the interim frames. Some products generate more created frames than others. These differences cause the type and frequency of artifacts to vary from product to product.

In addition, the digital video look which people want to avoid in traditional movie viewing, varies greatly from product to product. It tends to be more exaggerated on smaller screens than on larger ones. If you are projecting a 60" diagonal image, the effect will be more obvious than if you use that same projector to throw a 120" image. The digital video effect can sometimes be more obvious and distracting on plasmas and LCD TVs than it is on the projectors we've seen.

Contents: The Technology When to Use It The Importance of Frame Interpolation

Reader Comments(16 comments)

Posted Oct 22, 2012 11:46:41 AM

By Adam

Post a Comment Alert Moderator
If cinephiles want the most authentic, director-intended look, they certainly have that option, and that's respectable. Manufacturers understand that market is never going away. But every viewer has the absolute right to control their picture to taste, especially without being chastised for some perceived treasonous destruction of art.

I think interpolation looks great with certain things like documentaries, animated films, sports, and video games. Though with many films it does seem to reduce the dreamy, filmic look and turn CGI effects into cartoons and environments into back-lot sets. Even the most ardent supporter of the technology admits it's not ideal for every situation. But it's a nice option to have for those who enjoy it. Thanks Evan for the detailed and unbiased article.

Posted Mar 8, 2011 11:05:49 AM

By Charles

Post a Comment Alert Moderator
"There is an assumption amongst film afficionados that the "soap opera effect" is absolutely undesirable. Certainly to THEM it appears to be undesirable. But is there any evidence of this for the general public?"

I don't consider myself a film snob. Just someone with taste and perception. The power of film and visual storytelling comes from the images conveying another living world to the viewer, a world separate from the mundane setting of your own living room. What is the point of watching a movie if it doesn't transport you to another world or if it doesn't tap into that part of the brain that dreams about what's beyond the horizon? Having a technology installed as a default in every new TV that turns our dreams into something as cheap as the latest Youtube clip from The Young Turks is just plain wrong.

I feel sad knowing that there are people out there with no appreciation or understanding of the power of film, escapism and imagination, and only care about whether something looks "smooth" so they can show off their new expensive system to their friends. I feel sad knowing that these people don't understand that the power of visual storytelling comes from images that bespeak of other places, rather than images that sit dead, right there in front of them. I feel infinitely worse knowing that such people make up such a large part of the population that they can apparently dictate the way all visual art, both past and future will be seen the world over.

That is my opinion. I'm not sure I care for what the general public, joe sixpack if you will, wants.

Posted Jan 28, 2010 5:31:26 PM

By pjmit

Post a Comment Alert Moderator
High frame interpolation is necessary for and works well with PC games, and in SOME movies, especially old ones, watch the old Alien movie on regular DVD and play on a projector with FI, its a sight to behold.

Posted Sep 26, 2009 2:49:37 PM

By dtelmo

Post a Comment Alert Moderator
Hello everyone,

Does anybody know if the `frame interpolation` feature is available in any blu-ray player or media player ?

Many thanks! dtelmo

Posted Feb 11, 2009 9:51:53 AM

By rickirick

Post a Comment Alert Moderator
I'm curious to know if people are sensitive to motion judder in a selective fashion similar to how some people are sensitive to DLP rainbows.

For example, I have always found it very difficult to watch any LCD-based device when motion is shown. I've mentioned this for years and most people didn't seem to know what I'm talking about. With FI now a big deal, many people are recognizing this a problem, but many others are saying it has never been a problem for them.

So I'm curious about the science...are some people just more sanative to this than others?

It bothers me to the point that during some scenes (movies or sports or really any type of media) I have to close my eyes and wait for the action to stop. This is true on both LCD TVs and LCD projectors.

It is also a function of distance to the screen, so it would be nice to see some effort to quantify the impact of judder as a function of distance & screen width.

Posted Feb 7, 2009 5:13:12 AM

By Reuben

Post a Comment Alert Moderator
I have seen and own equipment that implements this varying technology, and the only thing you need to understand is that it's inserting frames where the frames were not recorded in the first place.

To me, that's almost like watching a movie in the incorrect aspect ratio...

Posted Feb 6, 2009 9:28:59 AM

By Darryl

Post a Comment Alert Moderator
Great Article! I like how Evan as a professional reviewer, is not stuck in the 'old school', is open to new improvements, and brings a more unbiased view. I am seeing more and more how other reviewers are stuck in the old school thinking, and not open to improvements like FI as important.

I think FI is going to be a big part of the future of home theatre movie viewing, and the key to it is two fold: 1. It may take some time to get used to it because we've been used to judder for so long & came to accept judder as being surreal. 2. I think the bigger the screen you have at home, the better. If you are watching a movie from more than 12 feet back on a 100ft(or less) screen, you may notice the 'soap opera effect' too much. However if you are 12 or less feet back and have a 120+ ft screen, then I think it will be much better & FI becomes a smoothness improvement to enhance the movie experience free of judder, rather than an annoying effect.

If they start using this new technology in theatres then we will definitely get more used to it quickly as the new standard way film should look. For now, my only fear is that once people get used to it at home under the right aspec ratio distance circumstances, going to the theatre will become less appealing because judder will become more noticeable than it used to be (at least until more theatres start adopting the use of this technology).

Posted Feb 1, 2009 3:51:42 AM

By dom

Post a Comment Alert Moderator
ive got this on my sanyo and love it is the best thing since sliced interpolated bread lol best thing i can say is embrace the future or chill in the past if you dont like it fair enough but make sure you get to view it and have a machine where you can turn it n and off to your liking

Posted Jan 23, 2009 11:15:57 AM

By Grant

Post a Comment Alert Moderator
O.K. I'll have to eat a little crow. My comments below were based on my observations with playback from my HTPC with a BD/HD DVD drive. Frame interpolation simply won't work with the HTPC - too bad since this is what I use the most for playback. Out of curiosity I tried both my Samsung BD player and Toshiba HD DVD player. FI works really well (completely strips away the film look) with very few artifacts. Animation looks 3D and spectacular!!! Normal playback with the HTPC is fine so I'll use it for movies and FI for animation and T.V. sports etc. This makes me wonder if some BD players may have problems with Epson's FI since others have been complaining.

Posted Jan 23, 2009 6:58:49 AM

By Grant

Post a Comment Alert Moderator
If you're interested in frame interpolation then stay away from the Epson projectors. I have lived with the 7500 for a few days now and for some content I love the look when FI is on; however, the artifacts introduced by Epson's FI are so bad that it renders FI unusable. It gets rid of film judder and introduces its own! Way too many hiccups and problems. Epson needs to fix this and soon or suffer the consequences! Hard to believe it would put a "broken" product on the market. Did no one at Epson actually take a look to see how well FI worked before it was released into the marketplace?

Posted Jan 21, 2009 3:53:30 PM

By Don

Post a Comment Alert Moderator
I know what Mike is talking about. I haven't seen the frame creation on a projector yet. But I was evaluating my options and looking at televisions at Best Buy, and one really caught my eye. I really wasn't sure at first whether it was showing a documentary about the making of Pirates of the Carribean or the movie. I had to watch it a few minutes just to decide it was really the movie. It was certainly attention grabbing, but I don't think I would want to watch a whole movie like that. A set playing T2 was also using a similar effect, and it made it look like a cheap direct to video show shot for the Sci-Fi channel or something. These were on LCD tv's I believe. I do wonder if the effect would not be so tiring/obvious on a bigger screen.

Posted Jan 21, 2009 3:14:04 PM

By Mike

Post a Comment Alert Moderator
I consider myself more in the "general public" than the "film snob" category, and I previously agreed with Aaron. I wanted the smoothest possible picture and payed no attention to talk of the "soap opera effect". I didn't have any interest in seeing motion judder, and have noticed it in numerous movies both at home on my previous projector and at the cinema. I was salivating at the chance to eliminate all that unwanted and distracting motion. I bought the Panasonic AE3000.

When I watch "Lord of the Rings" on DVD with the frame creation on Mode 2, many of the scenes suddenly look like a documentary of the film being made rather than a film itself. The actors suddenly look less convincing as hobbits. The scenery seems like a set rather than another world. I half expect the soundtrack to include the words "action" and "cut!" It's not that it looks unfinished or low-quality, it just looks so life-like that it's no longer surreal. Instead of being transported to Middle Earth, I am transported to the movie set.

I never thought I would be bothered by the "soap opera effect", but it is so powerful that it can disrupt my ability to lose myself in the movie.

I often leave the frame creation off now. I sometimes turn it on hoping that somehow I will acclimate to it and not notice the effect any more, but so far that hasn't worked. It's nice to know that I can probably turn on for sports and animation - I hadn't considered that before.

Posted Jan 21, 2009 6:34:19 AM

By Don Tujaka

Post a Comment Alert Moderator
Epson provides too much reality ?????? I haven't seen that since the late 60's, and we had a cure for it then. IMHO the most glaring problems with jitter I see is in sports programing so a high degree of correction is good. Like the article said, I can always turn it of when watching Casablanca.

Posted Jan 20, 2009 5:03:40 PM

By Jeremy

Post a Comment Alert Moderator
When characters in a movie become actors on a set, frame interpolation has gone too far. I used to play with frame interpolation (Trimension) on my pc outputting to a 106" projected image, it certainly was a neat effect, but the artifacts, motion cadence inconsistencies and soap opera effect were ultimately deal killers for me.

Posted Jan 20, 2009 4:18:45 PM

By Saied

Post a Comment Alert Moderator
I feel Aaron makes a fair point. I work in a cinema which uses 95% film prints and would say that it is not easy to recreate the film "look" electronically. The light behind the film will come from a xenon lamp and the film 24 fps is synchronised with a revolving shutter mechanism which keeps hidden the black stripe bits between each frame to help the eye's "persistance of vision" effect. A new film print will look excellent, but there is nothing worse than a print of an older title in poor condition - scratches, dust, hairs, frame jumps and bits missing where splices have been made, especially on heavy wear between reels. We occasionally do licensed DVD screenings using some kit you would have in your own home (Oppo 981 and DVDO HD, both SDI modded going into Panasonic 3 chip DLP PT-D7600). Screen is 16ft in 2.35:1 The result is great pictures which do get compliments, where the film "look" can be irrelevent. Before DVD, cinemas would happily show 16mm if necessary, without batting an eyelid, even though that film medium would still be a quality drop for the audience. Mediums change - film itself was originally printed on dangerous nitrate stock, then acetate, and now polyester, each of which has subtley altered the film "look" even within the industry. In my humble opinion, the solution is to accept a certain quality threshold across the different technology mediums.

Posted Jan 20, 2009 3:29:20 PM

By Aaron

Post a Comment Alert Moderator
There is an assumption amongst film afficionados that the "soap opera effect" is absolutely undesirable. Certainly to THEM it appears to be undesirable. But is there any evidence of this for the general public? Personally I do not think I have any interest in the "surreal" effect of 24fps. I am much more interested in the smoothest, highest quality motion possible.

Post a comment

Commenting on this article is easy and does not require any registration. Your email address is necessary for you to activate your comment once it has been submitted. It will not be shown to other site viewers. ProjectorCentral reserves the right to remove any comment at any time for any reason. Foul language is not permitted, nor are personal attacks. All comments should remain on topic.

Name:

Email Address:(used only to confirm your comment)

Your Comment:

(Enter the numbers as they appear to the left)