deinterlaced output is not deinterlaced

Euisung...

Yes, "shutter effect" is interlaced lines.

Toast has the ability to burn AVCHD (and apparently QT and other formats) to standard and DL DVD disks. You can play them back on a Blu-ray player which is what I do. These disks cannot be played on a standard DVD player. The nice thing is that you do not need a Blu-ray burner or expensive BD disks.

I watched the video on my plasma which is a 1080i display. They will not play back on the computer directly from the burned DVD. I should add that to double-check, playback of the original QT content (which came from iMovie '09) results in the interlaced lines.

Hope that makes sense. Happy to answer any other questions. But now you have me wondering if playing back at full HD (1080p plasma) would yield different results...

--D

David, you are correct that if you but the "Blu-Ray" standard DVD in your Mac you will not be able to play it.

However, if you place it in your Mac and open iMovie 08, it will be recognized as a camera and you can import the movie as if were off a camera.

I haven't tried this yet in iMovie 09, but it should work.

Thanks for clarification.

My guess is that you don't see the interlaced lines because you are watching it on an 1080i TV. You only see those lines when you playback interlaced source on a progressive display (computer monitors), and 1080i display will show each field at different time (odd fields - even fields - odd - even... at 60 or 50 Hz) so you never see odd and even at the same time. If you can somehow play your BD format DVD on a computer you'll probably see the lines again, unless deinterlaced.

My wife will soon be back from India with her Sony that has a BD burner and I'll try this on my new FullHD tv. If it works -- then the problem is down to exporting 720p.

HOWEVER, I still don't understand why we are getting what looks like 2 interlaced fields EACH of which has combing.

Seems to me the combing built into each field is going to become visible as soon the the hdtv displays all 1080-lines. Moreover, hdtv's are progressive -- they are not interlaced.

So it seems that DEPENDING on the type of deinterlacer you will or won't see combing. Bob you won't. Weave you will. Adaptive, you may not.

Which means the problem isn't really gone -- it's still there. I'll bet your 720p hdtv is using bob.

In short, I don't think this problem with interlace goes away. Something is very different in 09 than 08. I don't know if it is intentional in 09 -- for example a side effect of adding stabilization, etc -- or if it is a bug. And, if a bug -- I don't know if it is consistent (one of the many remaining bugs in QT for example) or is based upon some deep variable in OpenGL or Quartz that is being left in the wrong state.

Right now 09 is only safe for those will to work with progressive. Or, don't care if they lose a qtr of the resolution of FullHD.

Steve Mullen wrote:
HOWEVER, I still don't understand why we are getting what looks like 2 interlaced fields EACH of which has combing.

Seems to me the combing built into each field is going to become visible as soon the the hdtv displays all 1080-lines. Moreover, hdtv's are progressive -- they are not interlaced.

So it seems that DEPENDING on the type of deinterlacer you will or won't see combing.

If combing was built into each fields, then wouldn't it be visible all the time? No deinterlacer nor single field off can hide combing if it was somehow mixup between fields. Resizing of interlaced frame due to stabilization and cropping causes this, which makes them unusable for 1080i footage.

But if you can hide combing with deinterlacing it means they are not damaged. I think David's test confirms that clean 1080i in and out of iMovie09 is still possible as long as you don't use those resizing operations.

Even 1080p HDTVs won't display interlaced fields because they are temporally apart by 1/60th sec not meant to be shown simultaneously. Good HDTVs will be smart enough to show the full 1080 res for static element and only separate fields on motion, average ones will simply separate 1080i into two 540p and line-double or interpolate it back to 1080 height, but in any case they will show the combing of a normal interlaced video.

"If combing was built into each fields, then wouldn't it be visible all the time?"

What saw with 09 when there was motion on 1080i was very clear TO ME.

1) there were two overlaid (left-right) "images" when I paused the QT Player viewing 1080i60 FROM iM09 exported using UPPER.

2) One image (field) had a zipper look with the zipper teeth on alternate lines.

3) The other image (field) had a zipper look with the zipper teeth on alternate lines.


This is not how the source looked -- nor how the output from 08 looks.


ORIGINAL FRAME (note within Frame combing):

A1
...B2
A3
...B4
A5
...B6
A7
...B8


If this frame (which is HOW iM works) was REINTERLACED incorrectly when exporting 1080I:

NEW ODD (note within Field combing):

A1
...B2
A5
...B6

NEW EVEN (note within Field combing):

A3
...B4
A7
...B8


WHICH WOULD CREATE NEW INTERLACED FRAME:

A1
A3
...B2
...B4
A5
A7
...B6
...B8

NOTE HOW THE COMBING IS TWO-PIXELS HIGH!

WHICH WHEN PAUSED WOULD LOOK LIKE THIS -- WHICH IS WHAT I SAW:

A1
___A3
...B2
___...B4
A5
___A7
...B6
___...B8


WHAT WOULD CAUSE THE RE-INTERLACE TO PULL A PAIR OF LINES FROM THE ODD FIELD FOLLOWED BY A PAIR OF LINES FROM THE EVEN FIELD?

1) You have suggested a lack of an Interlace Flag. First, I don't think iM08 or IM09 uses an Interlace Flag. Anyway, I don't see why the line counter would increment in the way it does were the field treated as progressive.

2) A program bug in IM09 would do this nicely. But, it could also be in QT.

WHEN YOU TRY TO EXPORT 720P.

FIRST THE DE-INTERLACE:


A1
,
...B2
,
A5
,
...B6
,

EVEN BEFORE THE DOWNSCALE -- THE "PROGRESSIVE" FRAME HAS COMBING.

WHEN YOU EXPORT 540P -- IT WORKS BECAUSE IT SKIPS THE RE-INTERLACE AND SIMPLY GRABS THE ODD FIELD.

That sounds quite strange. No resizing would cause that kind of field rearrangement, at least none I can think of, and I haven't seen the same problem. (Can you post a screen grab?) What if you reinstall iM09?

So far, to me iMovie09 behaves not too different from iMovie 08. 720p output is broken because iM09 doesn't apply single field processing by default, and lower 1080 output has a bug. But beside that iMovie 09 requires users to be as cautious as they would with iM08 when dealing with 1080i - "Say No on resizing 1080i"
Difference is that iM08 was more prone to applying single field process, so any potential field damage was hidden easily. What I would want from iM09 is smarter way of handling 1080 video - only deinterlace when necessary.

"That sounds quite strange. No resizing would cause that kind of field rearrangement, at least none .."

AS I REMEMBER, that was 1080i exported -- not resized -- from the Upper 1080i setting. This is why 1080i output looks so bad -- excluding, of course, any re-sizing done by your use of PIP and Stabilization. I saw it when working with 09 at the Apple store.

The only difference between Upper and Lower in 09 is the use of Classic and Clean on the export. As far as I've read, they both are unacceptable.

08 in both capture and operation works just like 09. Single-field processing isn't used except for DV. 1080i is always WEAVE de-interlaced into 1080p --> two fields combined into one 1080-line frame. This is why if folks plan to use PIP and Stabilization -- they should not use 1080i. There was no need to be careful with 1080i in 08 unless they re-sized to a smaller frame-size -- which I doubt anyone did.

You claim 720p output is broken because it doesn't use "single-field" processing. I don't think that is true as QT de-interlacing is NEVER done by using only a single field. That would drop temporal sampling by 50% which would cause video to strobe as does 1080p30 and 720p30. That's not what happens with QT -- so that can't be what's wrong.

De-interlacing is done by running a 3-line Kernel though both fields to create a 3-line blend within a frame.

So I think 09 does de-interlace and then re-size (which is the correct order), but because something is "wrong" with way the 1080-line frame is treated during the de-interlace, it looks really bad.

This happens because after iM uses the QT API to obtain export parameters from you -- it checks them and can alter them. For example, no matter the frame-rate you set it always ignores it and uses the Project frame-rate. I assume that when it notices LINES = 540 it resets the parameters to grab the upper field from a 1080-line frame. I assume that when it finds LINES = 480 it resets the parameters to use only 240-lines and scale them to 480 before encoding.

I assume it's here that iM09 screws-up the parameters it sends to QT that causes the line indexing problem. After working with the parameter list, I assume it gives the list to the QT to execute.

PS: If you want to use PIP and Stabilization you either need to shoot 1080p30 -- not 24p -- or de-interlace 1080i60 to 1080p30 using MPEGStreamclip. Apple is not going to "fix" 09 so PIP and Stabilization can be used with 1080i. (Although they could adaptive de-interlace 1080i to 1080p during capture -- if they cared to support BD.)

Steve,
Thanks for the detailed post, but there seems to be some discrepancies between our experiences with iM09/1080i.

Steve Mullen wrote:
AS I REMEMBER, that was 1080i exported -- not resized -- from the Upper 1080i setting. This is why 1080i output looks so bad.

By 'bad' I assume that you mean those garbled interlaced lines, not normal ones. For me, as long as I don't do anything that alters size of 1080i in edit, upper 1080i export looks what it should.


Like this. This is how the original 1080i looks, and the upper 1080i output looks. So at least a safe pathway of 1080i in and out is possible.

The only difference between Upper and Lower in 09 is the use of Classic and Clean on the export. As far as I've read, they both are unacceptable.

Lower export out of iM09 is broken. It should only add the aperture flag, but instead it also resizes the original from 1920x1080 to 1888x1062, and back to 1920x1080 + aperture flag. The effect of which is this.


Upper setting again is showing the normal interlaced footage.

08 in both capture and operation works just like 09. Single-field processing isn't used except for DV. 1080i is always WEAVE de-interlaced into 1080p --> two fields combined into one 1080-line frame.

At least for the display in viewport both use single field. I had one occasion with 09 where it showed full frame in viewport, and resizing viewport caused interesting side effect like this one.

When I saw this I was so sure that iM09 was not doing singlefield for 1080i at all, but after a system restart I never see the same phenomenon again.

There was no need to be careful with 1080i in 08 unless they re-sized to a smaller frame-size -- which I doubt anyone did.

Only case would be 'cropping' but I don't think it's used much.

You claim 720p output is broken because it doesn't use "single-field" processing. I don't think that is true as QT de-interlacing is NEVER done by using only a single field. That would drop temporal sampling by 50% which would cause video to strobe as does 1080p30 and 720p30. That's not what happens with QT -- so that can't be what's wrong.

iMovie08's 720p doesn't use QT's deinterlacing, but single field. If deinterlaceing is used, instead of there should be 'ghosting' on moving objects.
When I export 1080i from iM08 in 720p (upper) there is no ghosting, which leads me to think that one field was dropped. Loss of temporal resolution is inevitable when you go from 60i to 30p, but the ghosting from deinterlacing serves sort of like motion blur to smooth out the jerkiness. I don't think that is the case for iM08.

If I export 720p form iM09 with 'deinterlace the source' checked on, it should create the movie with the ghosting but no ugly combs. However that feature is broken and I always get ugly combs.

So I think 09 does de-interlace and then re-size (which is the correct order), but because something is "wrong" with way the 1080-line frame is treated during the de-interlace, it looks really bad.

Again, different from my experience. But iMovie09 seems to act erratically case from case.

I assume that when it notices LINES = 540 it resets the parameters to grab the upper field from a 1080-line frame. I assume that when it finds LINES = 480 it resets the parameters to use only 240-lines and scale them to 480 before encoding.

Right. But I think iM08 grabbed upper field whenever LINES = not 1080, therefore 720p looked fine. iM09 does that only when LINES = 540 or less, and 720p is ruined.

I just exported 640x360 and 1600x900 respectively from iM09's 1080i project. Smaller movie doesn't show any side effect of interlaced footage, and bigger one has that ruined fields all over the place. I did the same test from iMovie08 and neither movies show the hint of interlaced source. No fields, no damaged fields, no ghosting, as if the source was progressive. So I think iM08 uses singlefield whenever the output size is not 1080.

My conclusion is based on my test only so I wouldn't say this is definitive, but so far iM09's behavior has been explainable this way, except for some random buggy ones.

I'm currently happy that I mostly understand where things are going wrong.

I'm not claiming to know why they go wrong but I feel I know what to avoid doing and how to work around these issues.

There appear to be two problems arising here.

Firstly QT has a problem deinterlacing properly. The QT engine itself seems OK since it works just dandy with final cut and other 3rd party applications that use QT. However if you utilise QT through the QT pro interface or through im09 then the problem begins.

It doesn't seem to matter what resolution you export to, if your source is interlaced and you want to output to a progressive QT movie (using movie to QT movie) then you will run into problems using QT or im09. It appears that adding scaling during export doesn't cause this problem but rather exaggerates it.

QT ISN'T exporting interlaced video, but it isn't deinterlacing properly either, it seems to simply be taking the interlaced video as you would see it on a progressive display and making it progressive (or at least that's how it looks visually)

The work around is to export to the same format as your source and use a third party deinterlacer.

I note on some other sites that Apple are aware of this and are working on it, although I'm not sure where this information comes from or whether it is correct. To me this issue is likely a bit like not having a fuse in the plug on your toaster, easily fixed but until it is the problems are quite dramatic. (I don't feel as though the QT engine itself needs ant fixing).

The second issue seems to be with im09 itself, the topic was first raised by Steve and seems to have now been clarified by Euising, in that choosing the lower resolution settings seems to cause scaling rather than simple flags being added to denote the aperture settings.

Of course the solution to this is simply to choose the upper settings when exporting.

Certainly with my set up the problems are inconvenient but always surmountable, although there does seem to be some instances where different people are getting different results. This may actually be the case, but I have to wonder if this doesn't simply arise from slightly different settings or indeed not fully understanding what each of us is trying to explain in our posts.

"QT ISN'T exporting interlaced video, but it isn't deinterlacing properly either, it seems to simply be taking the interlaced video as you would see it on a progressive display and making it progressive (or at least that's how it looks visually) The work around is to export to the same format as your source and use a third party deinterlacer."

1) It seems you both agree that using UPPER one can get good 1080i in and out -- as long as no resizing inside. My concern is that a week ago when there were were multiple postings about iM 09 -- it seemed that folks couldn't do this. There were postings that said when it came to 1080i -- there was a big difference between 08 and 09.

2) Maybe my memory of what I saw at the Apple store is faulty in that I was looking at a 720p not a 1080i export. If so, then the odd pattern I described is the broken interlace-to-progressive function.

3) Or, maybe there is a random system aspect to all this which means we shouldn't be surprised to find our experiences don't always match. Certainly, even those using FCP also find strange export problems.

4) It's possible the version of QT makes a difference. 7.6 is not yet approved for Avid's Media Composer and according to an Avid Poster, 7.6 is auto-loaded when you install ilife 09 even though you think you have only installed 7.5.5. It's interesting there have already been fixes for iphoto etc, but none yet for imovie. Perhaps that's because the QT group needs to do something and they aren't ready yet.

5) Assuming the de-interlace problem gets fixed -- there is still the problem that the internal use of WEAVE de-interlacing by iM08/09 puts two fields into one 1080-line frame. This means re-size (PIP and Stabilization) and those FX that "should" be applied field-by-field (Green-screen) aren't going to work work well with 1080i. This eliminates much of the value of 09 -- particularly since the Share-to-iDVD didn't fix the quality issue.

Steve Mullen wrote:

1) It seems you both agree that using UPPER one can get good 1080i in and out -- as long as no resizing inside. My concern is that a week ago when there were were multiple postings about iM 09 -- it seemed that folks couldn't do this. There were postings that said when it came to 1080i -- there was a big difference between 08 and 09.

To be honest here I feel quite guilty that I have previously posted misleading information. I believe what happened was that by my 504th test export, im09/QT had become messed up in some way and results simply couldn't be relied upon.

I did see bad 1080i exports, but this doesn't seem to be the case any longer. I hadn't noticed the subtle problems of exporting to the lower settings through im09, but right now I'm happy that I can fulfil my own requirements, which are basically to archive my im09 edits to AIC, should the tv ever support a better format than 960 x 540.

3) Or, maybe there is a random system aspect to all this which means we shouldn't be surprised to find our experiences don't always match. Certainly, even those using FCP also find strange export problems.

I think this could well be the case too.

4) It's possible the version of QT makes a difference. 7.6 is not yet approved for Avid's Media Composer and according to an Avid Poster, 7.6 is auto-loaded when you install ilife 09 even though you think you have only installed 7.5.5. It's interesting there have already been fixes for iphoto etc, but none yet for imovie. Perhaps that's because the QT group needs to do something and they aren't ready yet.

I have to wonder when QT will be fixed, I'm guessin' all the QT guys are busy with QTX at the moment and maybe fixes with the current QT software aren't getting everyone's full attention.

5) Assuming the de-interlace problem gets fixed -- there is still the problem that the internal use of WEAVE de-interlacing by iM08/09 puts two fields into one 1080-line frame. This means re-size (PIP and Stabilization) and those FX that "should" be applied field-by-field (Green-screen) aren't going to work work well with 1080i. This eliminates much of the value of 09 -- particularly since the Share-to-iDVD didn't fix the quality issue.

I'll have to do some tests, problems with PIP will likely be difficult to notice since the window is so small ordinarily, but window size is controllable so maybe it's worth a shot. Green screen requires me to paint my living room wall so that's a non starter for me. The most likely candidate for testing is stabilisation, which I haven't even gotten around to trying yet. Lord knows as I advance in years this may be a major feature for me, although I suspect any problems will be quite subtle.

"To be honest here I feel quite guilty that I have previously posted misleading information."

I wasn't talking about you -- there were posts that had 2-pixel high combing and some with having uneven patterns. Maybe these were 720p exports. I honestly can't remember what posts they were in.

I'm going to go back to the store and try another 1080i and 720p export.

Steve Mullen wrote:
5) Assuming the de-interlace problem gets fixed -- there is still the problem that the internal use of WEAVE de-interlacing by iM08/09 puts two fields into one 1080-line frame. This means re-size (PIP and Stabilization) and those FX that "should" be applied field-by-field (Green-screen) aren't going to work work well with 1080i. This eliminates much of the value of 09 -- particularly since the Share-to-iDVD didn't fix the quality issue.

iMovie09 does apply single field process if your output size is 960x540 or smaller. It is done to the source, so those resizing operation won't cause any interlace anomalies and all looks fine, as long as you don't mind reduced temporal resolution 🙂
Share to iDVD internally sends 960x540 version of your cut to iDVD project so you can at least get nice 30p DVD movie, although not 60i to 60i HD-SD conversion.

Green screen doesn't necessarily require field level application, although it's always safer that way. Unless you want to do high-end visual effects compositing in iMovie, greenscreen should be usable for 1080i source.

I am seeing the same issue. I have found ways to get around the issue through the source video. These problems did NOT happen in iMovie08.

Here are the results of my testing with the following:

Export settings through quicktime:
- MP4, H.264, 5000kbit/s data rate, Optimized for Download, 1280x720, framerate current, key frame every 24, Restrict profiles to Main, encode mode best quality
- Streaming enabled, Max Packet 1450, Max Packet duration 100ms


Camera: Canon HF100 (AVHCD)

All video was input as the full 1920x1080 option.

1920x1080 24p input video: Lots of the weird interlacing.
1920x1080 30p input video: No interlacing!
1920x1080 60i input video: Lots of weird interlacing.

So it looks like the fix (at least for me) is to keep all my video in 30p until this gets fixed. This is quite frustrating because everything was fine in iMovie08. I even took an existing project from 08 and ran the export in 08. I changed absolutely nothing. The output video of 08 is perfect while 09 has tons of the interlacing.