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[HELP] Color Range in MXF Metadata (colour_range_Original)
#1
Hey everyone.

I have a problem with broadcast files, created with Adobe Media Encoder (ARD-ZDF certified). So this seems to be a Adobe related problem, but maybe I can get some input here. When I export a file using the ARD-ZDF HDF02a-1.1 Profile preset, the MXF file has (among others) the following meta data (in MediaInfo):
 
Color range : Limited
colour_range_Original : Full

The file itself is encoded in "Legal Range" (like every common YUV encoded stream), but FFmpeg for example seems to interpret these files als "Full Range" (Premiere and Resolve are fine). As a result, all trancodes are "wrong" (lifted blacks/lower highlights). The "_Original" flags are the one from the stream, the tags witout  the "_Original" are the flags of the container as far as I know.
Where does the "_Original" flag come from? In my test the source was a ProRes (444 and 422HQ) file (Legal Range).
Of course I am able to fix this issue during transcoding in FFmpeg, but sometimes I don't have the choice in automated workflows.
 
To sum up: is the "colour_range_Original : Full" correct and necessary on ARD-ZDF HDF02a-1.1 Profile files? The TecSpecs say "Color Range [221W]: 897" (https://www.ard.de/die-ard/ARD-ZDF-HDF02...ks-100.pdf). Dunno what that means...


Attached Files
.pdf   mxf-profile_ard_zdf_hdf02a_-_v1.2.pdf (Size: 1,29 MB / Downloads: 73)
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#2
_Original = tag of the stream (only appears if both stream&container tag are present and differ)
Since you are dealing with tv related content, limited range usually is the right choice.

Cu Selur
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#3
Feedback from Adobe:

The original AVCI 50/100 specification in 2005 had a mistake, requiring the full range flag to be set in the bitstream even though the content is always legal range.  The solution is to make sure the wrapper is marked as limited range, and for applications to interpret the decode range according to the wrapper, not the bitstream.  Professional media applications have been aware of this specification glitch for ages and have handled it correctly. If we were to export AVCI 50/100 with the full range flag set to false, it would not conform to the spec, and many media validation tools would fail the file.
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