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Problem:

• In Windows I export from Sony Vegas to AVI (CineForm).  In OS X I read the file into FCP and apply the SmoothCam effect, then export to ProRes.  In Windows, Sony Vegas, I replace the original file with the smoothed one.  The levels/gamma are wrong.

Solution (Search):

• Sony Vegas forum http://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=4&MessageID=718371
  • Use DNxHD
    •  Couple of tips re DNxHD:  709 color level assumes 16-235, and RGB assumes 0-255.
  • Force it back again: www.kenstone.net/fcp_homepage/gamma_mac_pc.html
    • But this presumably implies getting re-quantized twice (the roundtrip issue and the forcing), which for 8-bit footage I imagine could reduce the quality (banding).
• Uncertainties
  • Where and how does this gamma get applied?  In FCP I didn’t (knowingly) alter the levels (eg until it looked right), I just applied the SmoothCam filter.  So I guess it would look wrong on the (pre-SnowLeopard) Mac but I wouldn’t care.  Wouldn’t FCP then export back whatever it got but smoothed?  This one is really confusing.    Experiments needed (when I get time…) I guess.

How easy is it to use ProRes in Avid MC4 these days?  Obviously relevant to using FCP-generated media in AVid but also for establishing the practicality of using the Aja KiPro recording device - a hot topic for lots of people.

I am an extreme newbie on Avid, though experienced in some other NLEs, and I am not yet au fait with the basic Avid quirks and ways.  I read that it is possible to import ProRes but that there can be issues with level shifts (gamma & 709 etc.).  Is this true and is there a workaround for it?  If levels issue was solved then would there be any further issues?

I did try searching via Google and in the Avid forum but precise intelligence on this subject was thin on the ground.  Most people seem to just convert ProRes to DNxHD; what I’d like to know is whether it’s practical to avoid that and just use ProRes-encoded media directly.   Maybe that’s a very naive perspective, as my experience below hints at…

I did a quick experiment to Import some ProRes to an Avid project (on Mac).  The ProRes I had available just happened to be SD (35 sec clip, 180MB).  The project was HD (I just accepted this as default).  Importing it caused it to do “Creating video from QT”.  [Avid:(bin)>Clip>Reveal] showed that this “creation” had produced (in a generic Avid scatch area) a set of three MXF files, two of 3.5MB (the stereo audio channels maybe?) and one of 500MB, which I assume is the upscaled version of the original media.  It was not playable by QuickTime or recognized by VideoSpec.  Meanwhile, the bin I imported to listed a QT (.mov) file of the same name as the original ProRes file but its datestamp (in the bin) indicated it had been created just now and it was listed as being of type DNxHD 120 (not the original datestamp or codec i.e. ProRes).  I wonder if it is a Reference file, just pointing to the content in the MXF files, and in that case whether the original ProRes file could (in principle) now be deleted, if that original file is not being used by the project.  I wonder where the reference file (if that’s what it is) is located.

Next I tried a more sensible experiment: Import SD ProRes (PAL DV 50i LFF, 27MB) into a matching project.  Again got the “Creating video from QT” message but it completed more quickly (presumably because it didn’t need to upscale and involved less data).  The resulting (created) MXF files were two of 772KB and one of 19MB.  The bin listed the imported file under its original name (.MOV) but being of type DV 25 411.  The “411″ is news to me - PAL DV uses “420″ colour sampling whereas “411″ is for NTSC.  Makes me want to call “911″…    I guess (and hope!) this message is just the result of a “lazy” bit of coding in Avid, i.e. that it hasn’t really re-sampled my media’s colours into colors…  Even if it hasn’t done that, DV is a lossy format (hence I suppose the slightly smaller file size than the original ProRes) and I would have preferred some kind of “visually lossless” format (can DNxHD also handle SD resolution?) here.  Maybe I need to attain some Avid-Wrangling skills. On a hopeful hunch I briefly tried Avid’s AMA but it didn’t recognize the folder containing my ProRes files as an AMA-compatible volume.  On a previous occasion I had used AMA successfully with a folder of XDCAM-EX footage and that had worked fine, so I just hoped … but my hopes were dashed.

It looks on the face of it like there’s no choice: Avid generates its own equivalent files in its preferred format (MXF-Avid) automatically, not just re-wrapping the “rival/alien” ProRes stuff but transcoding it into DNxHD (for an HD project) or DV (for a DV project).

But it’s early days in my Avid experience and I will find out more…

Someone switching from Vegas to Avid, seeking advice:

•  http://community.avid.com/forums/t/78524.aspx?PageIndex=1

Example advice from that thread:

• (Implicitly, from the following) Try AMA as a first port of call.
• “Import” is used for file types that can’t be accessed via AMA (Avid Media Access). There are two types of Importing: fast and I guess what I’d call slow.
  • Fast Import rewraps the file in an MXF container, but it does not transcode, so it takes very little time and there is absolutely no quality hit. 
  • Slow Import is necessary when the codec is not natively supported inside MC or one of the import settings dictates a transcode, e.g. going from 601 to RGB color levels (hard remapping all colors so 16 becomes 0 and 235 becomes 255).  Slow importing can take time
• Avid will most certainly accept (content in) a MOV container, but will always generate new MXF mediafiles when you import these MOVs into the system.
  • Indeed that’s what happened when I imported a MOV file containing ProRes content.  The MXF was about the same size as the MOV.
  • I guess this would have been an example of Slow Import
    
• Avid works mostly with its own codec, and with some other codecs. Not with ProRes.

The comment about ProRes conflicts with advice I have read elsewhere (and repeated elsewhere on this blog).  Possibly it is context-dependent (e.g. PC/Mac, Avid version, QT version, workflow) ???  I will reserve judgement until I have tried it.

Eugenia recommended ([http://eugenia.gnomefiles.org/2008/09/15/prores-for-windows/] as of September 2008) DNxHD and ProRes, among other codecs, for transfer between PC and Mac.   She also advises Lagarith for transfer to/from linux, though it sounds slightly tricky.According to BobRusso (Applications Specialist at Avid) [http://community.avid.com/forums/p/62217/407573.aspx#407573]:<<< 

You can install the ProRes decoder on a system without FCP:

• http://support.apple.com/downloads/Apple_ProRes_QuickTime_Decoder_1_0_for_Mac

• If you have FCP, even on another system, you can in principle just drop the codecs into your Library>Quicktime folder.

Make sure you have the latest version of the Avid codecs. They can be downloaded here:

• http://www.avid.com/red/AvidCodecsLE_DMG_1.10.zip

I suggest using MPEG Streamclip to convert the files: http://www.squared5.com

>>> 

The Aja KiPro captures HD (& SD?) from analog or SDI to 10-bit 422 to QT-ProRes (ordinaire and HQ).   In comparison the Convergent Design products currently capture to 8-bit 422 (hi-bitrate Mpeg2).  ProRes is particularly suited to (aimed at) Final Cut.  But since ProRes decoder is freely available, including on Windows, the KiPro could be used with other NLEs.Presumably (haven’t yet tried) once the ProRes is  copied to the editing system’s media drive, it can be simply dropped into an Avid project (bin/timeline).  Some seem to find it OK e.g. “I import ProRes straight into MC all day, no problems. You’ll need FCP 7 to have access to the new 4444 codec though..” [http://community.avid.com/forums/p/76196/426097.aspx#426097].  But some people are cagey about this (on principle?) “…if I were you I would reencode the quicktimes to an Avid codec” [http://forums.creativecow.net/thread/45/866733#866733].  One re-encoding option [http://community.avid.com/forums/p/62217/407573.aspx#407573] is Mpeg StreamClip [http://www.squared5.com].  Not sure what the advantage is (or whether it is real) but some people complain of problems with levels [http://community.avid.com/forums/p/62217/407573.aspx#407573] and metadata.  I would hope that Avid’s “New Thinking” would render any such problems historical, but experience will tell.One slight nuisance - Avid doesn’t work directly with the Aja KiPro.  That is, the KiPro is not a device type recognized by Avid’s Advanced Media Architecture AMA [ http://community.avid.com/forums/t/71260.aspx?PageIndex=1 ].  Not a show-stopper, but definitely a tilting force (from Avid to FCS/FCP).The KiPro is bulkier than the Convergent Design products.  It can record from more kinds of input to more kinds of storage medium. I haven’t looked at power consumption or robustness yet. Links: 

• http://dv411.com/kipro.html 
• http://provideocoalition.com/index.php/atepper/story/ajas_kipro_records_prores422_directly_without_a_computer

Gleaned from Philip Bloom’s presentation on using a 30p native cam to produce to other standards (e.g. 24p):

• Edit native, convert the edit result, not the source (rushes). Saves render time (& space)
• Don’t edit H264 - current machines are not fast enough to avoid jerkiness.
  • Before edit, convert to ProRes (standard is sufficient, no need for HQ).  If disk space at a premium then could instead use XDCAM EX format but that is not compatible with Cinema Tools.
    • Conversion to ProRes is done twice as fast by Mpeg StreamClip (free) than by Compressor.
      • Mpeg StreamClip:
        • [File > Open Files, File> Export to QuickTime, choose format ProRes 422, change top-slider to Full 100% Quality (default is less)
        • Can also use it to batch-convert, result can be either separate files or all concatenated in sequence.
• (DO THE EDIT)
• FrameRate Conversion:
  • Simplest: speed change - change the timebase (the rate at which the existing frames are presented).  OK when speed change does not matter (e.g. static scene).
    • Can be done e.g. via Cinema Tools.
      • Stages: Analysis then select desired new framerate then Conform.
      • (or [Cinema Tools: File > Batch Conform],  select a folder containing set of files, select any example file in it, Open, change speed, go: all the files are done)
  • Speed-preserving frameRate conversion can be done by Compressor or by JES Deinterlacer (free)
    • Compressor
      • Open Compressor
      • Drag file to job-strip
      • Create a Setting if needed
      • Geometry (5th icon along) - set Frame Size to “100% of source” (to ensure Compressor setting doesn’t re-scale)
      • Frame Controls: Unlock
      • (ignore settings that don’t apply e.g. resize method)
      • Rate Conversion: choose the fastest you can get away with
      • It is not compulsory to set a Destination.
        • (what happens if not? same directory as source?  what filename gets generated)
          • If no destination specified then file goes to same directory, auto-named as the original filename plus the name of the export format Setting.  Example: From TRV 12-39 AvidGrade.mov it generated TRV 12-39 AvidGrade-QT ProRes Interlaced.mov, where QT ProRes Interlaced was a compression setting (previously defined by myself).  Incidentally the QT-DV was 35MB, the generated QT-ProRes was 47MB.
    • JES Deinterlacer
      • Choose >  (input your file)
      • Output > Compressor > Export
        • (nothing to do with Apple’s Compressor, at least I assume…)