Unclean transistions and "twinkels" in image-zooms in HD export of project...

Sorry, yet another FM4 problem from me… but I am using FM4 rather intensively at the moment.
A 20min/210 images project has been updated several times followed by an HD export to AppleTV. That went well for say 4times. In a fifth version of that proces(add of an image +resize of it), the resulting HD .mov file started to show unclean/“twinkeling” transistions; believe it or not but exactly in my best and most colorful Iceland fotos in the climax of my story. Not only in transistions but also during showing/zooming of images. It was so bad that I had to delete it and use a previous version for my show that evening. Later I re-tried the export and it was still there, although with a lower frequency.
It seems as if FM4 is bored with exporting my project again and rejects to do it properly anymore for my best shots! :slight_smile:

Any suggestion on what is going on here? Thx in advance!

Does this problem only affect the one image you added or the complete slideshow? can you post a “before” and “after” movie snippets (5 secs duration or so), so we can see the effect you are talking about?

It does not affect the one image but a significant part of the slideshow, Achim. I tried to attach two 5sec .mov files but it says “uploaded file type is not allowed” . Any suggestion?

Please can you, depending on the file size, upload them to a file exchange service or send them to support(at)boinx.com with reference to this forum post?

I transferred two 5sec(15Mb) .mov files to support@boinx.com using www.wetransfer.com Hope they arrive all right! One .mov shows one flicker(Iceland2 flickering.mov); the other .mov shows it without the flicker (Iceland2 no flicker). Imagine the slideshow not with one but 20-30 and more of those flickers: not good! Hope it brings light into the darkness!? :slight_smile:
PS. it seems you have to download the files using the download link that is in the email support@boinx gets from wetransfer.com. The email maybe not in English but in Flemisch(Dutch). Hope it works!

Thanks for sending in the files. I can see a flickering at the end of the transition. This flickering is coming from the video compression: The video frame is changing dramatically all over the screen at this time and therefor the compression algorithm needs lots of data to describe those changes. Unfortunately there is a typical “kilo bits per second streaming restriction” for the codecs that allows only to put a certain amount of data in one second of video. If this boundary is reached, the codec starts to decrease the quality of the video in order to keep the frame rate rather than the quality of the video and meet this restriction at the same time. The results are compression artifacts that looks like flickering because just two or three frames later the data rate is enough to establish full image quality again.

Maybe you have either changed this bandwidth limit in the compression accidentally or you are working on “on the edge” and for some reasons you sometimes hit the boundary. (Also there are keyframes, which contains the description of a complete image and may be those where at the right place in your first export)

You should be able to control this parameter in the “QuickTime” sharing option:

  • Start your QuickTime-Export
  • Select “Compression: Customize”, you will get a window showing the QuickTime Exporter settings
  • Select “Video Settings…” which gives you another window with the compression settings for the export.
  • The “Data Rate” option at the top right is where you can setup this boundary. Try “Automatic”.
  • close both QuickTime setup windows and continue with your export in FotoMagico.

Note: Those Export Setup Windows are coming from MacOS-X and QuickTime, we don’t have access to them and can’t make them nicer.

Thx Achim for your explanation which of course makes sense.
In the AppleTV sharing there is no option to control the data rate parameter; the estimated file size is 1.2Gb. When I try a Quicktime share with the same data; the data rate is already on “automatic” and the estimated file size is around 4Gb; that is significant more! How comes? Does that guaranty perfect quality of the end result? I used 30 frames/sec rate, does that makes sense or should 25frames/sec suffice?

The estimated file size is really an estimate only. You have to export the show to see if its differs in size (but in the end only the quality is what matters). Of cause the fps is one of the big factors in that term. I would prefer 30 fps because the AppleTV output runs at 60fps and so the AppleTV don’t have to triple some frames to “scale” the 25fps to 60 fps.

Achim, I tried a few alternatives to try to come up with a non-flickering HD .mov.
-Trying to Share/Quicktime for HD(1920x1080) results in a 4Gb .mov file which looks fine when played on my iMac but does not work with my Loewe Connect TV, who doesn’t want to play it for some reason.
-Share/Ipad for my Ipad2 (HD 720p) works fine, no flickering.
-Retrying Share/AppleTV(HD 1080p) results in a 1.2Gb .mov with flickering, not only in transitions but also in plain image display and zooms. It is accepted by the Loewe Connect TV all right, but the quality is not sufficient for me.

So the remaining problem is that I don’t know anymore how to come up with a flicker-free HD 1080p .mov file… knowing that it worked perfectly until a certain point. Starting the project from zero is a serious job and doesn’t garanty a good result.
Do you have any other suggestion?

Sorry for not answering in time! Did you made any progress?

Regarding your sharing with QuickTime: Did you setup the video-codec correctly? You have to setup the video codec in the QuickTime export process with the “Compression Settings…” button in order to get the right video codec in your QuickTime file. Please set this to “H.264” just like the attached screenshot. Please let me know if this helps. (in order to check if this works with your TV I recommend to create a rather short FotoMagico slideshow so that the export process won’t tale too long)

You may change the “Data Rate” setting to some high value if the quality don’t meets your expectations.

No progress anymore. I, sort of, gave up. I don’t believe in your QuickTime export suggestions. It used to work perfect with the AppleTV export. So the question stays: why did it stop working properly?

Please, can you send us a small portion of your slideshow as an FotoMagico document, so we can test the export with your images and settings?