View Bug Details

IDProjectCategoryView StatusLast Update
0002086DCP-o-maticBugspublic2021-09-20 12:53
Reporteroverlookmotel Assigned Tocarl  
PriorityimmediateSeverityminorReproducibilityalways
Status resolvedResolutionfixed 
PlatformMacOSOS XOS Version10.14
Target Version2.16.0 
Summary0002086: Custom scaling in DOM 2.15.160 has no effect if aspect ratio not changed
Description

In some cases, you may need to scale down the frame in a DCP to have the original image floating in middle of screen with a black box all around.

An example is where end credits have text dangerously close to edge of frame, and you want to reduce the size of the credits, so they have black margin on all sides.

DOM 2.15.x has a "custom scale" option where you can set size desired exactly in pixels.

So in this case:

  • Source is a scope 4K DCP (4096x1716)
  • Set scale on the content as "custom"
  • Select "Set size"
  • Enter scale to size 3686 x 1544 (4096 x 90% / 1716 * 90%)

In the preview, this does exactly as intended - image appears floating in centre of screen with black on all sides.

However, when the new DCP is made, the the scale setting has been ignored and the image fills whole screen, as in original.

Variants:

  • Setting "Re-encode JPEG2000 data from input" -> same problem
  • Changing one of the scale-to dimensions so resulting aspect is other than 2.39 (the original aspect) -> fixes problem
  • Cropping 1 pixel off left -> fixes problem

Therefore, I suspect what is going on is that DOM is assessing if each frame needs to be re-encoded or not. If aspect is not changing, it incorrectly thinks "I don't need to do any scaling here" and passes the frame through unchanged.

Steps To Reproduce

Carl, I'll send you a repro.

TagsNo tags attached.
Branch
Estimated weeks required
Estimated work requiredUndecided

Relationships

related to 0002081 closedcarl "to fit DCP"/"custom" controls don't update things properly 

Activities

carl

2021-09-19 22:01

administrator   ~0004538

Thank you - nasty! Should be fixed by c162f9d8b127f56b8da46b83908000611033e6a5 in v2.15.162.

overlookmotel

2021-09-20 12:45

reporter   ~0004542

Brilliant! Thank you for very swift fix.

Is 2.15.162 released yet? Can't see it at present at https://dcpomatic.com/test-download

If it's still in the works, no problem - will use the "crop left = 1" workaround in meantime. Just checking I'm not missing something.

carl

2021-09-20 12:46

administrator   ~0004543

Not yet - I'll make a build at some point in the next 12 hours, all being well!

overlookmotel

2021-09-20 12:53

reporter   ~0004544

Thanks for swift reply.

OK cool. No rush on my account, then. I need to remake some DCPs in next couple of hours which hit this bug, so I'll use the crop workaround. Will upgrade to 2.15.162 later on when it's released.

Bug History

Date Modified Username Field Change
2021-09-19 13:55 overlookmotel New Bug
2021-09-19 20:47 carl Relationship added related to 0002081
2021-09-19 20:47 carl Priority high => immediate
2021-09-19 20:47 carl Target Version => 2.16.0
2021-09-19 20:47 carl Estimated work required => Undecided
2021-09-19 21:55 carl Assigned To => carl
2021-09-19 21:55 carl Status new => confirmed
2021-09-19 22:01 carl Status confirmed => resolved
2021-09-19 22:01 carl Resolution open => fixed
2021-09-19 22:01 carl Note Added: 0004538
2021-09-20 12:45 overlookmotel Note Added: 0004542
2021-09-20 12:46 carl Note Added: 0004543
2021-09-20 12:53 overlookmotel Note Added: 0004544