Allow review/transcoding of more channels, like "Z", "Y", "XYZ", "AR", "AG" "AB"

[BigRoy]

Changelog Description

Allow review/transcoding of more channels, like "Z", "Y", "XYZ", "AR", "AG" "AB"

Additional info

Do not error if review or transcoding happens on EXRs that only contain e.g. "Z" channel or "Y" channels.
Allow more channel names to pass through.

Fix #989

Testing notes:

1. Regular EXR publishes, that contain RGB or RGBA channels (even with named layers) should continue to work as they did.
2. EXR with only Z-channel should be transcoded fine.
3. EXRs with non RGBA channels or the other esoteric ones should not raise the error.

---

1. Maya publish render with transcode should still come through fine.
2. Houdini publish render with transcode should still come through fine.
3. Throw esoteric EXRs into Tray Publisher, transcoding should work fine (if ExtractOIIOTranscode settings are configured to actually transcode the files of course.)

[Copilot]

Pull Request Overview

This pull request adds support for transcoding and reviewing additional channel names (e.g. "Z", "Y", "XYZ", "AR", "AG", "AB") in EXR files.

• Updated allowed channel names for detecting reviewable channels.
• Replaced the previous per-layer RGBA extraction with a more flexible channels-by-layer approach and implemented new prioritization/sorting for layer names supporting varied channel configurations.
• Modified error messaging to include the channel names present if no suitable channels are found.

[Copilot]

Pull Request Overview

This PR enhances EXR transcoding to support additional channel types beyond RGBA (e.g., Z, Y, XYZ groups, AR/AG/AB) by extending channel-detection logic and adding error handling for missing channels.

• Introduces MissingRGBAChannelsError and updates convert_colorspace calls to catch and skip on missing reviewable channels.
• Extends get_review_info_by_layer_name to detect XYZ, colored mattes (AR/AG/AB), luminance (Y), and depth (Z) channel sets, and adds a sort priority for layers.
• Updates the extract/transcode plugin to use the new exception and avoid errors when uncommon channel combinations are encountered.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
client/ayon_core/plugins/publish/extract_color_transcode.py	Added exception handling around convert_colorspace to skip representations with missing channels.
client/ayon_core/lib/transcoding.py	Defined new MissingRGBAChannelsError, enhanced get_review_info_by_layer_name for extra channel types, and raised the new exception in get_oiio_input_and_channel_args.

Comments suppressed due to low confidence (2)

client/ayon_core/plugins/publish/extract_color_transcode.py:169

• [nitpick] The variable name unknown_rgba_channels could be clearer—consider renaming to missing_rgba_channels to match the MissingRGBAChannelsError exception.

                unknown_rgba_channels = False

client/ayon_core/lib/transcoding.py:418

• New branching logic handles AR/AG/AB, Y, and Z channel sets; consider adding unit tests to cover these cases and ensure correct behavior.

        elif all(channel in channel_info for channel in ("AR", "AG", "AB")):

[philippe-ynput]

not tested but LGTM

[iLLiCiTiT]

You removed "red", "green", "blue" and "alpha".

[BigRoy]

That's correct - but if you check the old code.. it'd have never been used. Because at line 389-391 it would only ever have used R, G, B. And since we stored them as .upper() it should've then also checked RED, GREEN, BLUE keys, right?

So I'm just removing it because it was never used... and I couldn't find any example files that actually had those channel names

[iLLiCiTiT]

It is was using first character to store it for mapping, but this condition is to skip the channel if does not match the items in set -> 2 different things. Put it back please. Because you've changed the logic you broke it, so also resolve that plase...

(e.g. Beauty.red would be skipped)

[Copilot]

Pull Request Overview

This PR expands the transcoding review functionality to support additional channel types (e.g., "Z", "Y", "XYZ", "AR", "AG", "AB") and refines error handling when suitable channels are not detected. Key changes include:

• Addition of tests verifying behavior for new channel types.
• Introduction of the MissingRGBAChannelsError custom exception for signaling missing reviewable channels.
• Modifications to get_review_info_by_layer_name to support extended channel detection and prioritization.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
tests/client/ayon_core/lib/test_transcoding.py	Added tests covering new channel scenarios and ensuring RGB priority over Z channels.
client/ayon_core/plugins/publish/extract_color_transcode.py	Updated file conversion logic and error handling with MissingRGBAChannelsError.
client/ayon_core/lib/transcoding.py	Extended channel detection in get_review_info_by_layer_name and added a custom exception.

Comments suppressed due to low confidence (2)

client/ayon_core/lib/transcoding.py:392

• Using only the first character of 'last_part' loses information for composite channel names (e.g., 'XYZ', 'AR'). Consider using last_part.upper() to preserve the full channel identifier.

channel = last_part[0].upper()

tests/client/ayon_core/lib/test_transcoding.py:90

• Consider adding tests for composite channel names (e.g., 'XYZ', 'AR') to verify that the updated channel detection logic handles them correctly.

def test_rgba_priority(self):

[BigRoy]

Added unittest with some "example channel names". Note that it does not actually go through testing EXR files, only by some channel names.

[Copilot]

Pull Request Overview

This PR extends the EXR transcoding functionality to support additional channel names such as "Z", "Y", "XYZ", "AR", "AG", and "AB". Key changes include:

• Updated tests in tests/client/ayon_core/lib/test_transcoding.py to validate handling of esoteric channels.
• Enhanced channel detection and prioritization logic in get_review_info_by_layer_name within transcoding.py.
• Integrated error handling for missing RGBA channels in extract_color_transcode.py by catching a new custom MissingRGBAChannelsError.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
tests/client/ayon_core/lib/test_transcoding.py	Added tests for handling multiple channel configurations.
client/ayon_core/plugins/publish/extract_color_transcode.py	Updated file processing logic and error handling with the new error type.
client/ayon_core/lib/transcoding.py	Introduced MissingRGBAChannelsError and revised channel mapping and prioritization logic.

Comments suppressed due to low confidence (1)

client/ayon_core/plugins/publish/extract_color_transcode.py:193

• [nitpick] Consider consolidating the two consecutive error log statements into a single log statement to improve log clarity and reduce redundancy.

self.log.error("Skipping OIIO Transcode. Unknown RGBA channels"