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http://www.pantarheon.org/AviSynth3DToolbox/

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.

AviSynth hasn’t changed in ages.  However there is a Multi-Threaded version, which responds appropriately to the MT() filter.

• URL: http://avisynth.org/mediawiki/MT
• [MT_07.zip]
  • Includes MT(), a Multi-Threading “Meta-Filter”
  • Also includes associated MT-oriented version of AviSynth, v2.5.7.5.

From [ http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=761070 ] referring to [ http://forum.doom9.org/showthread.php?t=140233&page=3 ].  Does low-pass filter “automatically” during resizing to reduce twitter/shimmer/aliasing etc.

• source=AviSource(”d:\fs.avi”).ColorYUV(levels=”TV->PC”).AssumeTFF  #Expands levels if frameserved in YUY2
• IResize(source,720,480)
• function IResize(clip Clip, int NewWidth, int NewHeight) {
  •   Clip
  •   SeparateFields()
  •   Shift=(GetParity() ? -0.25 : 0.25) * (Height()/Float(NewHeight/2)-1.0)
  •   E  = SelectEven().Spline36resize(NewWidth, NewHeight/2, 0,    Shift)
  •   O  = SelectOdd( ).Spline36resize(NewWidth, NewHeight/2, 0,   -Shift)
  •   Ec = SelectEven().Spline36Resize(NewWidth, NewHeight/2, 0,  2*Shift)
  •   Oc = SelectOdd( ).Spline36Resize(NewWidth, NewHeight/2, 0, -2*shift)
  •   Interleave(E, O)
  •   IsYV12() ? MergeChroma(Interleave(Ec, Oc)) : Last
  •   Weave()
• }

Spline36Resize can be replaced by another resizer if you wish.

http://wn.com/Avisynth__Slow_motion

Performance results for deinterlacing by TDeint plugin within AviSynth (2.5.8 32bit single-thread).  Other versions of AviSynth exist, including 64bit multithread, though not all plugins are compatible with these.

• SD 720×576 50i  → 720×576 25p, duration 14.5 minutes.
  • MBP (2010): 9 minutes.

They all work fine.  Initially there were some teething problems, due to a bad installation of AviSynth, though that cause was not immediately apparent (meaning I spent hours experimenting and Googling before the moment of that realisation…).  Versions installed:

• AviSynth 2.5.8 rev. 2
• AvsP 2.0.2
• Avs2Avi (Created 6 July 2004, size on disk 84 KB)

The main symptom of the teething problems: An AviSynth [.avs] script ran OK inside AvsP, to save to an AVI file, but before the dialog could ask me what codec, it failed with error message saying it could not open the source (.avs) file. (more…)

• http://www.turtlewar.org/avfs/avfs_1.0.0.5-readme.txt
• http://www.turtlewar.org/avfs/

It is possible to use the open-source ffmpeg to transcode XDCAM-EX files to other formats, such as DNxHD.Information from http://www.dvinfo.net/forum/sony-xdcam-ex-cinealta/112018-mfx-details-compatibility-what-about-ffmpeg.html as of 2010-12-23:

•  ffmpeg -i input.mp4 -vcodec dnxhd -b 60Mb -acodec copy output.mov
  • 60Mbit is a 720p bitrate.
• This is a good ffmpeg for pro users help site:
  • http://www.itbroadcastanddigitalcinema.com/ffmpeg_howto.html
• This is the command line I got from Baptiste who is developing the DNxHD stuff in ffmpeg.
  • Progressive:
    • fmpeg -i inputfile.mp4 -vcodec dnxhd -b 185Mb -acodec pcm_s16le outputfile.mov
  • Interlaced: (The difference is the -flags +ildct)
    • ffmpeg -i inputfile.mp4 -vcodec dnxhd -b 185Mb -flags +ildct -acodec pcm_s16le outputfile.mov
• And this is a link to a DNxHD white paper:
  • http://www.avid.com/resources/whitepapers/DNxHD_WP3.pdf
    • Dead link as of 2010-12-23; use http://www.avid.com/static/resources/documents/solutions/DNxHD.pdf instead.
• We are thinking of using 36Mbit DNxHD but all people we talk to say to use 185Mbit or maybe 120Mbit and that 36Mbit is for offline.
• But if you don’t have a problem using allot of GB on disc then go for Max Mbit for the specific resolution and framerate you use:
  • 1080p/25 DNxHD 185 1920 x 1080 8bit 25fps = -b 185Mb
  • 720p/50 DNxHD 175 1280 x 720 8bit 50fps = -b 90Mb
  • 1080i/50 DNxHD 185 1920 x 1080 8bit 25fps = -b 185Mb
• More settings for other framerates:
  • http://www.itbroadcastanddigitalcine…#Encoding_VC-3
    • Has many commandlines and DNxHD settings, though sadly none for 1080p50 (as I require).

Information from http://forum.doom9.org/showthread.php?t=130781

•  FFmpeg is now providing Avid DNxHD (SMPTE VC-3) encoding and decoding features

http://videoeditorskit.sourceforge.net/

•  We provide and maintain PremiereAVSPlugin - a plugin for Adobe Premiere that allows Avisynth scripts to be imported as normal video files