In fact you can hardly see the banding on a TV a lot of the time.Īnother thing I realised is that if you calibrate your Mac display properly then the banding is less noticeable. They only happen on certain types of footage (subtle and/or noisy shadows), and they look a lot worse on a high-res Mac display than they do on a TV (which is where many people will be watching home movies). IMovie ’09/’11’s banding problems won’t bother many people. Even Final Cut ends up with a bit of banding in many of these scenarios. Colour banding is an inevitable result of transcoding highly compressed footage. Now many would say I’m being picky here, and they’d probably be right. So it appears to be a problem with the way iMovie transcodes from the source video to the output, rather than a simple output encoding issue. What’s interesting is that you don’t get the banding when exporting any iMovie-rendered content such as maps and globes. Unfortunately, many photos contain dark, subtle gradients – and, since they aren’t moving around, you notice the problem more.įor more examples see Clay Alchemist’s post, Why iMovie is a FAILURE, as well as this review of iMovie ’11 by HDSLR Review. ![]() Many people on the Apple forums have reported this problem when using still photos within iMovie (see here and here), but the truth is it happens on any image (still or video) that contains dark, subtle gradients. The resulting quality was pretty much identical to iMovie ’06 – i.e. (By the way, I got a friend to run these tests using Final Cut Pro. As you can see, as well as introducing ugly banding, the posterization effect kind of amplifies the noise, making it much more noticeable and annoying: IMovie ’09 (Exported via QuickTime, H.264, Best quality) (click image to enlarge):Ĭheck out the trackpad and surrounding area. IMovie ’06 (Exported via QuickTime, H.264, Best quality) (click image to enlarge): Original iPhone 4 footage (click image to enlarge): However, the effect is noticeable, to a greater or lesser extent, in areas of subtle shadow in most 720p footage. Here I’ve deliberately used some fairly low quality source footage with subtle, noisy shadows to make the effect clear. (I’ll buy iMovie ’11 at some point – if I can bring myself to – just to confirm this.) ![]() Incidentally, although I’m using iMovie ’09, the banding is apparently just as bad in iMovie ’11. It’s usually not so noticeable because the iPhone 4 is higher res, and also much less noisy, than my old DV camera. The posterization is still there in the shadows. Surely iMovie ’09 should produce perfect results with iPhone footage, right? After all, they’re both Apple products! Recently, though, I got an iPhone 4 which shoots 720p HD. Ironic that a program from 2006 gives better results than one from 2009, but there you go. Even if I deinterlace the footage first with MPEG Streamclip (which produces a very nice result BTW), iMovie ’09 still butchers the deinterlaced video, producing the same horrid output.Īnyway, for my DV footage I gave up on iMovie ’09 and reverted back to iMovie ’06, and I’m very happy with the results. ![]() However, I eventually realised that the interlacing is not the problem here. Now if you scour the Apple forums you’ll find many people telling you this is because iMovie ’09 deals poorly with interlaced footage, by dropping every other field from the movie, effectively halving the resolution. iMovie ’09 has absolutely butchered (I don’t think that’s too strong a term) the footage. Take a look at the shadow below his head. ![]() IMovie ’09 (Exported with HD option) (click image to enlarge): IMovie ’06 (Exported with Full Quality option) (click image to enlarge): Original DV footage (click image to enlarge): When I tried the same thing on iMovie ’06 (or “iMovie HD”, to give it its proper name), the result was fine. The output quality was really bad – it contained what I can only describe as severe posterization or banding in the shadows, which also had the effect of amplifying the noise in the movie. My new MacBook Pro came with iMovie ’09, so I decided to edit some 3-year-old DV tapes of my son that I still hadn’t dealt with. (This one has been driving me nuts for weeks…)
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