OpenEXR multilayer image truncated on save
Closed, ResolvedPublic

Description

System Information
NixOS 16.09, Linux kernel 4.4.47, NVIDIA GTX 970

Blender Version
Broken: 2.78a, 2.78b (built against OpenEXR 2.2.0)

Short description of error

When saving a 1280x720 render result as an OpenEXR multilayer image, with DWAB compression, the resulting OpenEXR image is truncated: only the bottom quarter or so of the image is saved, the rest is black or transparent.

This does not occur with DWAA or no compression. Changing the resolution to 1920x1080 also fixed it, but other resolutions make even more of the image disappear. Disabling some render passes also made the problem go away.

The render result:

The resulting OpenEXR image opened in Blender:

Blend file:

Broken OpenEXR file:

Exact steps for others to reproduce the error

  • Open attached blend file
  • Render (the blend file has Combined/Z/Mist/Normal/UV passes enabled).
  • Hit F3, save as OpenEXR Multilayer, DWAB compression, RGBA, Float (Full).
  • Load the resulting image into Blender.
Aaron Carlisle (Blendify) triaged this task as Confirmed priority.

This seems to be a bug in OpenEXR itself, which was fixed by [1]. Unfortunately, this commit is in none of the branches except from development one (it is not in the 2.2fixes branch).

[1] https://github.com/openexr/openexr/commit/c9a2e193ce243c66177ddec6be43bc6f655ff78a

From quick around seems we can not solve it from our side, just need to wait for the new OpenEXR to be released.

For until then will remove the broken compression setting from the interface.