[FFmpeg-trac] #9598(ffprobe:new): Wrong Chroma Location (Type 2, top left) for XDCAM Files (Type 0, left) in FFProbe

[FFmpeg]

#9598: Wrong Chroma Location (Type 2, top left) for XDCAM Files (Type 0, left) in
FFProbe
-------------------------------------+-------------------------------------
             Reporter:  FranceBB     |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  ffprobe      |                  Version:  git-
             Keywords:               |  master
  ChromaLocation                     |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:

 Whenever FFProbe tries to detect the chroma location of an XDCAM-50 file,
 it reports top left, namely 4:2:2 Type 2.
 Not only top left is invalid for 4:2:2 files, but it has been standardized
 "recently" (2013) for UHD HDR PQ BD in H.265 which are indeed 4:2:0 Type2
 (top left). The old MPEG-2 chroma placement is Type 0, namely "left" and
 it's the one being used in XDCAM-50 as it's an MPEG-2 standard defined in
 early 2003-2006 when Type 2 wasn't a thing and didn't even exist.

 This affects FFProbe and, as result, Avisynth indexers like
 LWLibavVideoSource and FFVideoSource which populate the frameserver with
 the wrong frame property.

 How to reproduce:
 {{{
 % ffmpeg -show_format -show_streams -i "input.mxf"


 ffprobe version git-45dc668aea
 built on 2021-11-07-git-45dc668aea
 }}}


 [STREAM]
 index=0
 codec_name=mpeg2video
 codec_long_name=MPEG-2 video
 profile=4:2:2
 codec_type=video
 codec_tag_string=[0][0][0][0]
 codec_tag=0x0000
 width=1920
 height=1080
 coded_width=0
 coded_height=0
 closed_captions=0
 film_grain=0
 has_b_frames=1
 sample_aspect_ratio=1:1
 display_aspect_ratio=16:9
 pix_fmt=yuv422p
 level=2
 color_range=tv
 color_space=bt709
 color_transfer=bt709
 color_primaries=bt709
 '''chroma_location=topleft'''

 This is yet a different XDCAM file I received from A&E:

 index=0
 codec_name=mpeg2video
 codec_long_name=MPEG-2 video
 profile=4:2:2
 codec_type=video
 codec_tag_string=[0][0][0][0]
 codec_tag=0x0000
 width=1920
 height=1080
 coded_width=0
 coded_height=0
 closed_captions=0
 film_grain=0
 has_b_frames=1
 sample_aspect_ratio=1:1
 display_aspect_ratio=16:9
 pix_fmt=yuv422p
 level=2
 color_range=tv
 color_space=unknown
 color_transfer=bt709
 color_primaries=unknown
 '''chroma_location=topleft'''

 and this is a movie I've got from Notorious Pictures and it says top left
 too:

 [STREAM]
 index=0
 codec_name=mpeg2video
 codec_long_name=MPEG-2 video
 profile=4:2:2
 codec_type=video
 codec_tag_string=[0][0][0][0]
 codec_tag=0x0000
 width=1920
 height=1080
 coded_width=0
 coded_height=0
 closed_captions=0
 film_grain=0
 has_b_frames=1
 sample_aspect_ratio=1:1
 display_aspect_ratio=16:9
 pix_fmt=yuv422p
 level=2
 color_range=tv
 color_space=unknown
 color_transfer=bt709
 color_primaries=unknown
 '''chroma_location=topleft'''


 Sample (valid for 7 days): https://we.tl/t-MhjJWTj0lQ

 This is reflected on Avisynth Indexers: https://i.imgur.com/f736Nld.png -
 https://i.imgur.com/igT1odL.png
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/9598>
FFmpeg <https://ffmpeg.org>
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