EXIF:PageNumber Tag Value Spec

[mazeckenrode]

In the course of trying to best utilize existing tags to store specific information for document and publication images, it seems like EXIF:PageNumber would be the logical tag to store a page number. When I attempted to use it to store one page number, I got an error saying that two values are required. The EXIF Tags page indeed defines PageNumber as int16u[2]. But I%u2019ve been unable so far to find any explanation as to why two values are necessary. Forum topic here and other web page here both utilize two values for this tag, but neither explains it. Is the second value the number of pages? Doesn%u2019t seem likely, as both examples above use 0 as one of the values. If I want to record that an image is of page 29 of an edition of a newspaper from 1975, but I don%u2019t know the total number of pages, how would I proceed?

PageNumber is not underlined in the EXIF Tags table, so it%u2019s apparently not in the official EXIF specification, and having searched for it in the linked PDF to make sure, I can confirm that it couldn%u2019t be found there. Explanatory text at the top of the EXIF Tags page states, %u201CAlso listed are TIFF, DNG, HDP and other tags which are not part of the EXIF specification, but may co-exist with EXIF tags in some images.%u201D But there%u2019s no indication which of these non-spec groups PageNumber belongs to, and apparently no page for TIFF tags exists among ExifTool%u2019s various tag pages. I did find reference to PageNumber among explanations of TIFF tags  here, but it doesn%u2019t say anything about multiple values.

[mazeckenrode]

Why does this forum always turn my typographical quotation marks and apostrophes into things like %u2019 when I edit my posts?

[StarGeek]

From page 55 of the Tiff Specification

This field is used to specify page numbers of a multiple page (e.g. facsimile) document. PageNumber[0] is the page number; PageNumber[1] is the total number of pages in the document. If PageNumber[1] is 0, the total number of pages in the document is not available.

[Phil Harvey]

About the %u2019 thing.  That is very odd, but I did find another poster that had this problem earlier this year, so it can't be just you.  What browser are you using?

- Phil

[mazeckenrode]

StarGeek — Thanks much, again. Figures, didn't think to look for that, specifically, and my first guess turned out to be correct after all.

Phil — My primary browser is Pale Moon, a fork of Firefox. The weird thing is, when I first post my messages here, the curly quotes are displayed correctly, but if I edit a post afterwards, they get substituted by strings like that.

[StarGeek]

Testing
" ' ' "
editing
" ' ' "

Strange, I'm using Waterfox and there are no problems here.  I thought Waterfox and Pale Moon were related forks, but I guess I was wrong.

[mazeckenrode]

Waterfox and Pale Moon are both forks of Firefox, but I thought Waterfox (which I haven%u2019t yet tried but keep meaning to) adhered more closely to recent Firefox design and layout than Pale Moon. I%u2019m also aware that there are two variants of recent Waterfox versions, Classic and Current. Which do you use?

My own test, again using Pale Moon%u2026

%u201CThis is a test%u201D %u2018 %u2019

%u201CThis is an edited test%u201D %u2018 %u2019

[mazeckenrode]

Now trying with SRWare Iron (a Chrome fork)...

"This is a test of the curly quote marks" ' '

"This is an edited test of the curly quote marks" ' '

[Alan Clifford]

Waterfox and Pale Moon are both forks of Firefox, but I thought Waterfox (which I haven%u2019t yet tried but keep meaning to) adhered more closely to recent Firefox design and layout than Pale Moon. I%u2019m also aware that there are two variants of recent Waterfox versions, Classic and Current. Which do you use?

My own test, again using Pale Moon%u2026

%u201CThis is a test%u201D %u2018 %u2019

%u201CThis is an edited test%u201D %u2018 %u2019

That shows several percent signs on firefox and on safari.

[mazeckenrode]

That shows several percent signs on firefox and on safari.

Yeah, I imagine they show no matter what browser you use to read it. The issue seems to be what browser I use to save an edit, following the initial post.