ID 462114 - Pixels are added to the bounding box when using a Mirror or Transform node and exporting an .exr image sequence from Nuke Studio/Hiero

Problem summary
Pixels are added to the bounding box when using a Mirror or Transform node and exporting an .exr image sequence from Nuke Studio/Hiero.

Customer reported version
hiero.12.1v4

Customer reported platform
windows10

Steps to reproduce

1) From Nuke Studio/Hiero, Read in any footage.

2) Place the clip on the timeline, then create a Mirror soft effect, and enable the vertical or horizontal knob.

3) Export the Sequence transcoded as .exr.

4) Import the image sequence into Nuke.

5) View the bounding box of the footage in the Viewer.

Also reproducing in Nuke:

Adding a Mirror downstream of a CheckerBoard and enabling either of the flip or flop knobs

set cut_paste_input [stack 0]version 13.0 v3CheckerBoard2 { inputs 0 format "1920 1080 0 0 1920 1080 1 HD_1080" name CheckerBoard1 selected true xpos 70 ypos -249}Mirror2 { flip true name Mirror2_1 selected true xpos 70 ypos -155}Viewer { frame 1 frame_range 1-100 name Viewer1 selected true xpos 70 ypos -100}

Expected behavior
The footage should have the same bounding box prior to the soft effects being applied.

Actual behavior
An increase of 2-3 pixels is added to the bounding box of the footage when using a Mirror node. The same can occur when using a Transform node when changing the Scale value to anything other than 1 for height or width.

This also occurs in Nuke with just adding the Mirror with horizontal or vertical enabled, or just a Transform node and viewing the results.

Workaround
Exporting other image sequence types (.png, .tif, .dpx, etc) does not have the issue occur.

Reprsoduced by Support in:

Nuketudio 12.2v3 - Windows 10

NukeStudio 12.2v1 - Windows 10

NukeStudio 12.1v1 - Windows 10

NukeStudio 12.0v1 - Windows 10

NukeStudio 11.1v1 - Windows 10

NukeStudio 11.0v4 - Windows 10

Unable to reproduce bug in:
NukeStudio 11.0v1 - Windows 10

Earliest version tested
NukeStudio 11.0v1 - This issue doesn't appear in this version and has regressed