TIFF IFD concatenations/removals output images that fail JHOVE validation check for value offset word-alignment

[fiendish]

(https://jhove.openpreservation.org/modules/tiff/)

> python -c 'import tifftools;tifftools.tiff_concat(["good1.svs", "good2.svs"], "out.svs", overwrite=True)'
> jhove -m TIFF-hul out.svs

Jhove (Rel. 1.24.1, 2020-03-16)
 Date: 2021-07-15 20:14:30 MDT
 RepresentationInformation: out.svs
  ReportingModule: TIFF-hul, Rel. 1.9.2 (2019-12-10)
  LastModified: 2021-07-15 20:14:20 MDT
  Size: 875685820
  Format: TIFF
  Status: Not well-formed
  SignatureMatches:
   TIFF-hul
  ErrorMessage: Value offset not word-aligned: 8842289
   ID: TIFF-HUL-4
   Offset: 8858224
  MIMEtype: image/tiff

https://web.archive.org/web/20160324105748/https://partners.adobe.com/public/developer/en/tiff/TIFF6.pdf on page 15 (about IFD entries) says:

Bytes 8-11 The Value Offset, the file offset (in bytes) of the Value for the field. The Value is expected to begin on a word boundary; the correspond- ing Value Offset will thus be an even number. This file offset may point anywhere in the file, even after the image data.

[manthey]

@fiendish Thank you for reporting this.

[fiendish]

I'm still getting the error after the change.

Test input (1.85 MB): http://openslide.cs.cmu.edu/download/openslide-testdata/Aperio/CMU-1-Small-Region.svs

> python -c 'import tifftools;tifftools.tiff_concat(["CMU-1-Small-Region.svs", "CMU-1-Small-Region.svs"], "out.svs", overwrite=True)'
> jhove -m TIFF-hul out.svs

Jhove (Rel. 1.24.1, 2020-03-16)
 Date: 2021-07-16 11:24:53 MDT
 RepresentationInformation: out.svs
  ReportingModule: TIFF-hul, Rel. 1.9.2 (2019-12-10)
  LastModified: 2021-07-16 11:23:01 MDT
  Size: 3877884
  Format: TIFF
  Status: Not well-formed
  SignatureMatches:
   TIFF-hul
  ErrorMessage: Value offset not word-aligned: 1276569
   ID: TIFF-HUL-4
   Offset: 1278040
  MIMEtype: image/tiff

[manthey]

@fiendish Try again.

[fiendish]

Looks great. Thanks!