[
https://issues.apache.org/jira/browse/PDFBOX-6199?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18076801#comment-18076801
]
Tilman Hausherr edited comment on PDFBOX-6199 at 4/28/26 10:54 AM:
-------------------------------------------------------------------
This is how it looks currently:
!image-2026-04-28-12-27-28-955.png!
I asked copilot about this. Besides advice that are not relevant IMHO, it
suggested to move the "grReferenceValue = ..." segment in
decodeTypicalPredictedLineTemplate1() above the line "for (int minorX = 0;
minorX < minorWidth; minorX++)". The explanation: "previously
{{grReferenceValue}} was effectively “drifting” and not being re-anchored to
the current 3-line byte window at each byte boundary."
Doing so brings this:
!image-2026-04-28-12-28-19-575.png!
So the triangles are gone. Moving "context = ..." as well brings this:
!image-2026-04-28-12-29-21-038.png!
I think Copilot has a point with the first change. The second change (by me)
may be wrong because the bottom blot is the "tear" from the "blemish" bitmap
that should be erased by the refinement.
Doing the same change for template0 results in a test failing.
was (Author: tilman):
This is how it looks currently:
!image-2026-04-28-12-27-28-955.png!
I asked copilot about this. Besides advice that are not relevant IMHO, it
suggested to move the "grReferenceValue = ..." segment in
decodeTypicalPredictedLineTemplate1() above the line "for (int minorX = 0;
minorX < minorWidth; minorX++)". The explanation: "previously
{{grReferenceValue}} was effectively “drifting” and not being re-anchored to
the current 3-line byte window at each byte boundary."
Doing so brings this:
!image-2026-04-28-12-28-19-575.png!
So the triangles are gone. Moving "context = ..." as well brings this:
!image-2026-04-28-12-29-21-038.png!
I think Copilot has a point with the first change. The second change (by me)
may be wrong because the bottom blot is the "tear" from the "blemish" bitmap
that should be erased by the refinement.
> Template 1 handling with TPGRON not supported
> ---------------------------------------------
>
> Key: PDFBOX-6199
> URL: https://issues.apache.org/jira/browse/PDFBOX-6199
> Project: PDFBox
> Issue Type: Sub-task
> Components: JBIG2
> Affects Versions: 3.0.4 JBIG2
> Reporter: Maruan Sahyoun
> Priority: Minor
> Attachments: image-2026-04-28-12-27-28-955.png,
> image-2026-04-28-12-28-19-575.png, image-2026-04-28-12-29-21-038.png
>
>
> {{bitmap-refine-template1-tpgron.jbig2}} tests the folling features of JBIG2:
> - Refinement region
> - Template 1
> - TPGRON
> - Reference bitmap reuse
> We currently produce garbled output when decoding
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
