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I am not the only one wondering, of the various kinds of de-interlacing tools/algorithms available, what are their relative advantages and indeed which one provides the greatest quality (or maybe quality/computation ratio) ?  This subject has been raised repeatedly on the Sony Vegas forum.  Most recently, the following have been of note:

• http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=768368
  • Subject: Perfectionists’ PAL<=>NTSC Conversion, Posted by: Nick Hope, 2011-06-29.
  • Various AviSynth scripts (posted) making use of QTGMC and MVTools.
• http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=773230
  • Comparisons of various methods in context of a home movie.
    • Mike Crash smart deinterlace plug-in for Vegas.
    • Vegas 9 Interpolate
    • Vegas - 9 Blend
    • Yadif plug-in for Vegas
    • Vegas Pro 8.0c to DNxHD to Handbrake.
  • It would be good to see a comparison against Nick Hope’s scripts and also Cineform’s HDLink.
  • John Meyer goes to some lengths to explain the importance of pixel-boundries etc.  Instructive.

Compression formats for Digital Intermediates when using Sony Vegas:

• http://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=4&MessageID=770173
  • Cineform for highest quality (smart-renderable)
    • Cineform (is great for transfer) between After Effects and Vegas.
  • MXF for almost the same quality at a fraction of the size.
    • MXF previews beautifully off small bus-powered USB 2 drives.
  • Quicktime .mov with png compression for anything with a transparent alpha layer.
  • Quicktime .mov with Avid DNxHD codec for Handbrake encoding intermediary and for working with the FCP world.

Details (again from the above link) about use of MXF:

• The big thing with MXF is to make sure that you use it interlaced even (if) you are using progressive footage.  …set it using one of the interlaced templates but set the deinterlace method to none.
  • The reason this is important is that Vegas will only smart-render .mxf footage flagged as interlaced. If you set the MXF render properties to progressive, it won’t smart-render. If you set the properties to interlaced and select either blend fields or interpolate, it will screw up resizes and renders to other formats.
• MXF with a smart-render is very cool. The format looks wonderful and no damage is done as you smart-render sections into a final piece.
  • MXF without a smart-render isn’t really good enough. MXF will not hold up to successive rerenders like Cineform or a lossless codec.

To see the effects of interlacing/combing and compare the results of different deinterlacing methods:

1. Insert a clip (e.g. 1080p50) to the timelineLeave clip’s properties unchanged (eg UFF).
2. Set Project Properties to same as the clip - except make the project Progressive.
3. Set Project Deinterlace method to None.
4. Set Preview to Good/Full.
5. Find a moment on the timeline where there is a good degree of motion (fast but remaining in-frame and not too blurred).

If Preview Scaling is Off then combing should be revealed in principle but may be hard to make out in practice - too fine a detail (1 pixel wide).Easiest workaround:

1. Set Preview Scaling to On then reduce the Preview pane size to not-quite half-size.
2. The “not-quiteness” (difference from exactly half-size) then generates a “Moire pattern” magnification of the combing - much easier to spot.

Now you can experiment with different types of deinterlacing - bearing in mind you are looking at something derived from the combing as opposed to the combing itself.  To clarify the -actual- combing, one can deploy Windows’ Accessibility-Magnifier - more realistic than the above though less convenient - as follows:

1. In Windows 7, do Control Panel > Ease of Access Center > Start Magnifier.
2. Best magnifier view-mode is a (rectangular) “Lens” (only available if Aero is enabled).  Default zoom level is (1:1) i.e no zoom.
3. The easiest way to change zoom level is Cmd+ and Cmd-, where Cmd is the Windows button on a PC or Command/Apple/CurlySquare button on a Mac (accessing Windows e.g. locally via Boot Camp or Virtual Machine).
4. Can change lens size via Ctrl-Alt-R then (with -no- mouse-buttons held) drag it.
5. Exit magnifier by Cmd-Esc.
6. Sadly no way to simply toggle On/Off, but in W7 you can pin it to the task-bar.
7. If magnifier control window gets buried by another window then it is still accessible as a permanently-on-top magnifying-glass icon.

• http://www.videocorp.cl/minisitio/hdv/pdf%20HD/editores/
  • Covers Adobe, Avid, Final Cut, Sony Vegas.
  • But references Sony Clip Browser 2.0, a version which is well-superseded (I currently use 2.6).
• http://pro.sony.com/bbsccms/assets/files/micro/hdtapelessworkflow/brochures/25633_AVID_Media_Composer_R2.pdf
  • References Clip Browser 2.0+

There is a free yadif (superior interpolation-based deinterlacer) plugin for Sony Vegas 10: http://www.yohng.com/software/yadifvegas.html  and  http://forums.creativecow.net/thread/24/923607. As I understand it, yadif is an advanced deinterlacer like in Handbrake, superior to Interpolate and Blend. There’s a beautiful graphical description of how it works at https://trac.handbrake.fr/wiki/yadif.

Summary:

• Cineform copes nicely with non-standard formats but DNxHD does not.

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Summary of my conclusions from my own limited experiments based around Sony Vegas (9.0e 64-bit):

• For HD 1080-50i, in its corresponding mode, DNxHD works as well as or better than Cineform.
• However for non-standard formats (like Vimeo SD-Wide 853×480), DNxHD does not work well while Cineform does.
  • Confirmed by separate experiment, reported separately.
• For my experiments (Sony Vegas 9.0e-64) the following DNxHD settings made no difference:
  • LevelSpace: RGB/709
  • Quality: 50% (default) or 100%

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• http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=760878
  • Choosing interpolate or blend has nothing to do with this particular process, you shouldn’t see any difference, but you do need to select one method or the other. The only point at which is make a difference is when you’re deinterlacing AND not changing the frame size. Then the deinterlace method WILL make a big difference. 99.9% of the time, I will use interpolate as blend will cause “halos” on the edges of moving objects.
  • 99.9% of the time, I will use interpolate as blend will cause “halos” on the edges of moving objects.

Sony Vegas: Guidelines for Fast Preview Speed (from Sony Vegas forum, http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=758370)

• Match project properties exactly to your source footage. Use the “match” feature to do this. Failure to have these settings correct is the biggest reason for slow timeline playback.
• Don’t use higher preview resolution than necessary. Use Auto instead of Full, and use “preview” or “good” instead of “best,” especially when smooth timeline performance is more important than being able to see every last detail.
• Turn off “scale video to fit preview window.” This doesn’t make a huge difference, but it helps.
• Make your preview window smaller.
• Set “Deinterlace Method” in “Project Properties” to “Interpolate” instead of “Blend”.
• Try setting “Thumbnails to show in video events” in “Video” preferences to “None”, especially for multicam projects.

http://wn.com/Avisynth__Slow_motion