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I have a Sony XDCAM-EX clip at 1280×720p25 to be transcoded to ProRes, so it can be used as source for iMovie (for another user on another machine).

In principle it should be very simple: go on Mac, use Compressor to transcode the XDCAM footage to ProRes.  But as usual, things are pernickety…

Sequence:

• First tried dragging the XDCAM [.mp4] file into compressor.
  • Not recognised.
  • Likewise the BPAV folder.
• Next, I transcoded the XDCAM footage to “MXF for NLEs” format, using the Mac version of Sony Clip Browser
  • Not recognised.
•  Next, opened the XDCAM Transfer app.
  • In this app, open the XDCAM’s BPAV folder.
  • The footage displays OK but how do I export it to a QuickTime [MOV] file?
  • Looks like I can’t.  It only offers to export to an [MP4] file.
  • Instead, I guess I’ll have to open it from FCP.
• FCP
  • I opened a random existing FCP project.
  • The footage is 720p but the project/sequence settings are arbitrary (unknown to me)
  • FCP: File > Import > Sony XDCAM…
  • It imported to somewhere … but where?
  • FCP Browser: file > RightClick > Reveal in Finder
  • It was at [/Volumes/GRm HFS+/_Media/_Projects/2010-05-30 (Esp) Alison Doggies/020 Source/Sony XDCAM Transfer/SxS_01]
• File System:
  • In other words, at whatever destination was last used by some app - presumably XDCAM Transfer or possibly FCP
  • The destination path was in fact specified in XDCAM Transfer, under its Menu: [XDCAM Transfer > Preferences > Import]
  • Moved the file instead to [/Volumes/GRm HFS+/_Media/_Projects/2009-11-22 (JRM) Lady of the Silver Wheel]
• Compressor:
  • Open it in Compressor
    • Drag it to the “job-strip” (my term) in Compresor.
  • Compressor displays data about that clip (e.g. 1280×720, 25 fps)
  • Select jobstrip settings:
    • Select Setting
      • Settings: Apple > Formats > QuickTime > Apple Pro
        • Name: Apple ProRes 422
        • Description: Apple ProRes 422 with audio pass-through. Settings based off the source resolution and frame rate
    • Apply (Drag) Setting to Jobstrip
  • Destination
    • Leave destination unspecified.  Then it will be the same folder as Source.
  • Processing (transcoding) of this footage (1280×720p25) took about 3 minutes (on MacBook Pro 2009).
  • Result was not that much bigger than the original:
    • Originally recorded [.MP4] file: 1.19 GB
    • Rewrapped [.MOV] from XDCAM Transfer: 1.14 GB
    • ProRes [.MOV] from Compressor: 1.97 GB

MyFrench friend wanted to know how to continue receiving French Satellite TV after November 2011, when existing channels on the satellites at 5W will be switched off.  Basically they are going to an MPEG4-related broadcast format, requiring a new generation of digital receiver.

The “least headache” solution we went for was a package and receiver called Fransat, which is available at Darty stores in France.  Ironic name, given the main channel we want to watch is Arte.

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I attended, working on one of the camera units.  Had a great time, learnt lots, at all sorts of levels.  Even how to make good use of the Movie Slate application on my iPhone!  Link: http://www.fstopacademy.com/

Explained in http://x264.nl/x264/10bit_01-ateme_pierre_larbier_422_10-bit.pdf and further documents at http://x264.nl/.  Would like to know what applications recognize this format though, and how would it be incorporated in a workflow involving standard NLEs (e.g. Avid MC or Sony Vegas).  Would it have to be transcoded to e.g. DNxHD first, and if so then how (what app etc.)?

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.

BBC R&D have determined the resolution levels people can typically perceive at the most common viewing distance, just under 9 feet.

• http://www.reghardware.com/2011/05/19/tv_sizes_deconstructed/page2.html
• http://downloads.bbc.co.uk/rd/pubs/whp/whp-pdf-files/WHP092.pdf

Some examples I draw from this:

•  For my 24 inch (diagonal) editing monitor viewed at 2 feet (my typical distance), this is equivalent to a screen of (9/2)*24= 84 inches (diagonal) at the study’s typical viewing distance.   Based on this, their results imply that I can resolve in excess of full HD (1920×1080).
  • Though a typical TV viewer might not sit at this distance, someone watching on a laptop or tablet etc. might well do.
• An elderly person I know sits at “about ten feet” from a 50 inch (diagonal) HD screen (a Panasonic 3D TV).  They notice little difference between SD and HD.  BBC results suggest they should be able to perceive up to 1280×720.
  • In addition to the possible ageing issue (deteriorating vision), I wonder if their TV incorporates any clever scaling algorithm to produce an image that is HD-smooth if not HD-detailed.  In principle algorithms can infer greater resolution from consideration of sets of frames, so detail-enhancement is not beyond the realms of possibility.

What if one wants to encode a non-supported format in DNxHD?  For example double-framerate HD at 1080p 50 fps?  I typically produce such material by double-framerate deinterlacing from HD footage.  Some cameras are also starting to appear that record directly at 1080p 60 fps.  DNxHD config panel doesn’t give options for this - but there appears to be a workaround:

• http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=745821

• <<Because there was not a 59.94 fps Progressive option in the DNxHD config, I thought it was not allowed. I chose the 1080p 25fps option in the DNxHD config & 59.94 fps in the “Quicktime 7″ panel - and it worked like a champ! All the way thru a HandBrake Render @ 59.94 fps.>

• I have not yet confirmed this by experiment.

• H264 Encoder Tips:
  • Some recommend the use of Handbrake (free encoder) over that in Sony Vegas 9 and earlier.
  • Sony Vegas 10 uses an updated version of the MainConcept encoder (for H264 etc.) than Vegas 9 etc.
    • I don’t know how this compares to Handbrake.
• Levels: Studio/Broadcast, 0-235.
  • Any levels outside this range will be preserved by the encode/decode but will get clipped at 16=black and 235=white.
  • Levels within the range will play back in Vimeo at 0-255 RGB on computer display.
• But what of gamma/colorspace?  601 or 709 or what?
• Framerate:
  • 30fps (as in USA) or 25fps (as in Europe etc.).
    • For nicer motion, might be worth mo-comp retiming 25 fps to 30 fps?
• Resolution:
  • 640×480 for standard definition
  • 4:3 video, 853×480 for widescreen DV
  • 1280×720 or 1920×1080 for high definition.
• Pixel Aspect:
  • Square, i.e. 1:1″ or “1.00″
• Interlacing:
  • None (Progressive)
• Encoding
  • MP4-(H264+AAC).  Other formats also possible but this one is probably the most popular.
    • H264:
      • Use 2000 kbits/sec for standard definition 4:3 video, 3000 kbits/sec for widescreen DV, or 5000 kbits/sec for high definition footage.
      • Profile = Main ?
      • Reference frames = 2 (default)
        • Each macroblock (or part of it?) can be predicted from a different reference frame.  Result can be higher quality but increased encoding time - since each Ref. Frame implies its own motion estimation.  A default of 2 or 3 is about right.  Higher values tend only to be helpful for animations.  Values above 5 rarely help.
      • Deblocking filter = Yes ?
    • AAC: 320 kbps / 44.1 kHz
  • http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=745821
    •  If you give them non-streaming source, the upload servers must do an extra preliminary pass to find the metadata, taking up more time and resources than is necessary. This has a cumulative effect on overall server response.

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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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How convert a [.flv] file to a [.mp4] file?

• http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=743501&Replies=7  (as of 2010-12-27)
  • Super by Erightsoft will open both types of FLV and convert them to something Vegas will understand. MPEG-2 is pretty universal. Experiment.
  • Very simple with Handbrake (which is free)
    • http://handbrake.fr/downloads.php
    • Just drag the .flv onto the handbrake gui, let it analyze the .flv file & when it’s ready click ’start’.
    • Handbrake creates a converted .mp4 which Vegas will recognize.