ID 323244 - When using DWAA and DWAB formats for exr compression, only the RGBA channels are compressed and not the other embedded channels

Follow
  1. The Foundry SANDBOX
  2. Bug Tracker
  3. Nuke

Problem summary
When writing out multichannel exr's using DWAA and DWAB compression formats, the additional layers outside of RGBA will not be compressed using the compression algorithm.

Customer reported version
nuke.10.0v5

Customer reported platform
n_a_linux

Steps to reproduce

Open attached script

OR

1) Create a Noise node, alter the x/ysize value to '2'

2) Create a ShuffleCopy node and connect both inputs to the Noise node

3) Create a new 'out' layer as 'noise' using all R,G,B,A channels (see image below)


​
​​
4) View the layers in the viewers channel selector, you should now have a 'noise' channel that is the same as your RGBA channel.

5) Create a Write node with channels set to 'all', as an 'exr' filetype, change the compression format to 'DWAA' or 'DWAB', choose a location and render one frame as render_all.exr

6) Duplicate the Write node and set the channels to 'rgba' and render named render_rgba.exr

7) Open the files in the file browser and compare file sizes.
Result: The RGBA only version should be around 5-10MB, the 'All' version will be around 20-30MB. As there is only an additional layer, the later should only be double the RGBA layer and proves that this additional layer was not compressed.

Workaround
Currently there is no workaround if you are using DWAA or DWAB compression. As this issue does not occur in the default compression of Zip (1,16) or other popular compression formats like RLE. We suggest using these compression formats if they are an option for your pipeline till a solution is created.

Reproduced by support
This problem has been reproduced on:
Nuke 11.0v3 - CentOS 6.9 - MacOSX 10.13 - Windows 7
Nuke 11.0v1 - CentOS 6.9
Nuke 10.5v7 - CentOS 6.9
Nuke 10.5v1 - CentOS 6.9
Nuke 10.0v5 - CentOS 6.9 - MacOSX 10.13 - Windows 7
Nuke 10.0v1 - CentOS 6.9 - MacOSX 10.13 - Windows 7

Earliest version tested
Nuke 10.0v1
- exr compression for DWAA/DWAB formats did not exists before this version

Expected behaviour
DWAA/DWAB compression formats in the exr exporter should compress the all the channels not just the RGBA channels

Actual behaviour
DWAA/DWAB compression formats in the exr exported only compresses the RGBA channel

    We're sorry to hear that

    Please tell us why