This issue is somewhat similar to others I’ve brought up before involving ExifTool and DOpus, but pretty sure I haven’t aired this particular set of specifics before. I’ve also brought this up in the ExifTool forum, in case anything useful comes of it, though no such luck there so far.
As stated in previous posts, I utilize both DOpus and ExifTool extensively in dealing with image metadata, mostly deal with images in PNG format, and a significant portion of my relevant work is spent on scanned pages from physical publications such as books and magazines, paper documents, and/or extracted/converted page images from PDFs. Adding unique and useful metadata to fields such as DESCRIPTION, SUBJECT, TITLE, COMMENT and TAGS (aka KEYWORDS) has always been a challenge, and my use of ExifTool has been instrumental in streamlining the process, but I also want the commonly-displayed metadata fields (mainly COMMENT and DATE TAKEN, for my purposes) to be displayable by DOpus, and previously found that it’s necessary to add those fields using DOpus prior to any subsequent manipulations by ExifTool, because the two tools don’t create new metadata in the same location within PNG files, and DOpus won’t display it when created by ExifTool, but ExifTool is reportedly capable of updating metadata in PNGs whereever it is found.
For page images derived from a 13-page PDF document, my filenames might look like this:
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 01.png”
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 02.png”
[…]
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 13.png”
I use DOpus (via SetAttr META
in custom command) to write the same value to what it calls DESCRIPTION, SUBJECT, TITLE and COMMENT in all 13 files, such as: General Company invoice 1234567890, account ABCDEFGHI-00001, 15 Dec 2020, total due $0.01, due date 5 Jan 2021, p 1/13; File as downloaded: “General_bill_December_15_2020.pdf” (296,175) [13 pp, 4347 w, 20097/23854 ch, 590 l]; Source: <https://www.general.com/gw/bill/docs/getpdf/gndoc?docName=General-Bill-12.15.2020&docId=YNAhNz8sXlzYk3n3dHidUX8hWkmiYZ5R9SbXOkGvcDcfsKLKtI22MkilMpEIdbItYozvYAGlzR0nmgg3Tdu6ZsAL1hxvnosmFcGx1sOSSd3fivVEkSQh2xQOPlDhouAU9yDpaJkhXGvV3vgjKBZWcB6rGbsAo6s6Uo72YGK2tDS8FbwP0PCQaYuknwWo0>
Then DOpus again to add TAGS (aka KEYWORDS), example: General; Company; PDF; Document; Screenshot; 2020-12-15; 2020; December; Bill; Invoice; $0.01; Due_2021-01-05; Due_2021; Due_January; Account_ABCDEFGHI-00001; Invoice_1234567890; Page_1
I ultimately want each page image to have metadata accurately reflecting its own unique page number, so I’m using a fairly complicated ExifTool command, created with much help from the guys in that forum last summer, that gets the page number from the filename (digits following “-
” at the end in this example, though could be followed by more text in some cases) and uses it to adjust p 1/13
to the resepectively appropriate number in DESCRIPTION, SUBJECT, TITLE and COMMENT in all files, and likewise bump Page_1
in TAGS/KEYWORDS.
The problem is, in some but not all cases, after I’ve run the ExifTool command to adjust the page numbers, DOpus won’t display the updated COMMENT, neither via mouse-hover tooltip nor via Set Metadata dialog / Metadata pane. The length of the data string appears to be a factor — the threshold in my tests seems to be 512/513 characters. ExifTool confirms that the metadata is, in fact, there in the COMMENT, and that it’s identical to the strings in DESCRIPTION/SUBJECT/TITLE for each file, and at most only one character off from the original (and correctly displayed) string written before the ExifTool manipulation. Furthermore, I can manually copy the updated string from any of the latter fields, paste it to COMMENT, and then it shows up as expected. But the copied/pasted/displayed string is exactly the same as the MIA one, as far as any method I can use to examine it goes.
In case anything can be gleaned from my test files, please see the attached 7-zip. Apart from ideally solving the mystery and/or finding a fix for it, assuming there’s any chance of either happening, it would be nice if I could use DOpus to programmatically copy from, say, DESCRIPTION to COMMENT in all selected files, but I’m not seeing any way to do that (unless it’s maybe another scripting-only solution).
Attached: “2021-03-29 17;18;54 - MAZE - MIA Comment Test.7z” (13,218)
Contents:
“2021-03-29 17;18;54 - MAZE - MIA Comment Test\”
“0 No Meta\”
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 07.png” (197) [1 x 1 x 1]
“1 DOpus\”
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 07 (512 ch).png” (8,152) [1 x 1 x 1]
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 07 (512 ch).png.json” (6,644)
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 07 (513 ch).png” (8,168) [1 x 1 x 1]
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 07 (513 ch).png.json” (6,652)
“2 DOpus+ExifTool\”
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 07 (512 ch).png” (11,380) [1 x 1 x 1]
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 07 (512 ch).png.json” (7,733)
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 07 (513 ch).png” (11,687) [1 x 1 x 1]
“2020-12-15 23;59;59 - General - xFGHI-00001 Invoice 1234567890 - 07 (513 ch).png.json” (7,743)