ProRes horizontal bar artifacts from near 0 value pixels

[jphowey]

Summary of the bug:
horizontal bars on output when input pixels are between 0.004 and -0.004. Bars are the color of prior frames with a transform. They are exactly 16 or 32 frames prior (black if before frame 16). If multithreading is turned off the bars are from 1 frame prior. Artifacts happen on specific RGB colors, when artifacts are produced, turning the image black and white or turning one or two channels black makes the artifact not show up.
How to reproduce:
I can provided source EXRs if requested. Render Linear EXRs at higher res than HD. Tested creating the artifacts at UHD. Built a CMSTestPattern in Nuke. Gained down to .06 with -0.03 offset. Flipped the image and merged over it's self with a dither mask. after that I animated an offset going from 0.01 to -0.02. Halfway through the animation the artifact happened.

% ffmpeg" -y -framerate 24 -pattern_type sequence -apply_trc bt709 -start_number 1000 -i "/Volumes/Public/RGS_0180_comp_HVE_v0034.%04d.exr" -vf "format=gbrpf32le" -c:v prores_ks -profile:v 3 -pix_fmt yuv422p10le -timecode 00:00:41:16 "/Volumes/Public/RGS_0180_comp_HVE_v0034_FullRes.mov
ffmpeg version
built on ffmpeg-118468-g19a2d26177 or ffmpeg-7.1 (tested both)

Patches should be submitted to the ffmpeg-devel mailing list and not this bug tracker.

[jphowey]

This is a downres'd version of the artifact. Original output of ffmpeg was UHD.

[MasterQuestionable]

͏    Blind guess:
͏    prores_ks yuv422p10le

͏    ffmpeg -y -framerate 24 -apply_trc bt709 -i "In_%d.exr" -vf "format=gbrpf32le" -c:v prores_ks -profile:v 3 -pix_fmt yuv422p10le -timecode 00:00:41:16 "Out.mov"
͏    [ ^ ͏"-timecode", ͏"-framerate" shall be unnecessary for reproduce. ]

͏    Try other codecs? (lossless in particular)
͏    So to ensure it's the encoder problem.

͏    ----

͏    From the preview of the effects (͏"XArtifactTestC_UHD_Source_v0034.mov"):
͏    Alike Inter-frame artifacts are mostly encoder fault.

͏    "near 0 value pixels"
͏    Assumed RGB #000000? (pitch black)
͏    (it's unlikely you mean yuv( 0, 0, 0 ); mild green)
͏    .
͏    Exact examples?