Removing the font size info from EPUB

[Buhaj47]

I have a number of EPUB books, each of them happens to have a different font size encoded. How to unify it so that the reader decides on which font size to use?

[theducks]

Originally Posted by buhaj47

I have a number of EPUB books, each of them happens to have a different font size encoded. How to unify it so that the reader decides on which font size to use?

You could use the conversion Filter Style Properties section.

A bit of a sledge hammer approach as it will get All font-size usage

Personally, I use the editor and decide as I go as to which get tweaked

[Buhaj47]

Originally Posted by theducks

You could use the conversion Filter Style Properties section.

Do you mean the "Filter Style Information" section when I choose the Convert option? I pick the "Fonts" box but that does not work.

[theducks]

Originally Posted by buhaj47

Do you mean the "Filter Style Information" section when I choose the Convert option? I pick the "Fonts" box but that does not work.

No
That box remove FONTS (hover for the Tool tip)
Use the Filter Style Properties box to enter what you want removed.
Use CARE.
Keep a backup copy

[BetterRed]

Originally Posted by buhaj47

Do you mean the "Filter Style Information" section when I choose the Convert option? I pick the "Fonts" box but that does not work.

@buhaj47 - did you try entering 'font-size' in Filter Style Information->Other CSS properties?

[Buhaj47]

Will it just unify the main body font-size of the books or rather make all the text (e.g. chapter titles) the same?

[BetterRed]

Originally Posted by buhaj47

Will it just unify the main body font-size of the books or rather make all the text (e.g. chapter titles) the same?

I have no idea, that's why I wrote - 'did you try'.

Before trying things always make sure you have a way to undo?

BR

[GeoffR]

Originally Posted by buhaj47

I have a number of EPUB books, each of them happens to have a different font size encoded. How to unify it so that the reader decides on which font size to use?

Since you have a Kobo device, you should get good results if you:

1. Make sure all the font-size parameters are specified in resizable units, i.e. em, %, small/medium/large, rather than absolute units such as px, pt, etc.

2. Avoid use of the font shorthand property; e.g. replace "font: 12pt Times" with individual properties "font-size: 1em; font-family: Times;"

I haven't looked in to how to do this automatically though, the number of books I have found with these sorts of problems is quite small so I just edit the stylesheet manually.

[JSWolf]

Originally Posted by buhaj47

I have a number of EPUB books, each of them happens to have a different font size encoded. How to unify it so that the reader decides on which font size to use?

I suggest you use the Edit Book feature of Calibre to have a look at the CSS and then you can make proper decisions as to which font sizes to remove. Sometimes there is a font size for chapter titles, title pages, copyright page, drop caps, small caps, first letter, and other things that you do want to keep the font size.

So manually deleting font-size directives is the best way to go about it. If you delete them all, then you could end up with things the wrong size.

[Buhaj47]

Thanks guys - however, I think I'm gonna give it a break and just focus on reading the books. I've opened some EPUB and KEPUB books in the editor, and can't find the information relating to the font size. The thing is all the EPUB's (I use for novels) I have have similar font size, the KEPUB's (historical books with footnotes and pictures) are much smaller. Think I could add the values GeoffR mentioned, but never really studied HTML code.

@GeoffR - unless could you show me a sample of how you add specific info on the font size the books should use, e.g. small/medium size for main body? If that's an issue though, don't bother, thanks anyway.

EDIT: I have opened an EPUB in the editor once more, and, correct me if I'm wrong, the main font used in the novel is defined by the parameters in calibre1 which are here. Does it mean it will suffice to add the information on the font size here, e.g. font-size: small? If I use zero value, will the reader apply its default settings (if such exist)?

[JSWolf]

For the main body font, you don't need to add a font size to it. No font size means it will be the default font size and you can then easily change the font size using the font size slider.

[Buhaj47]

I see, but what the font size shown on the screen depend on then, i.e. there must be a reason the books are rendered differently? Is this because they are in different formats, i.e. EPUB and KEPUB?

[JSWolf]

Sometimes a font size is specified in the CSS for the body font. Usually a small font size is used. So that does make a difference. I strip font sizes in the body text out as I don't need or want them.

[GeoffR]

Originally Posted by buhaj47

I see, but what the font size shown on the screen depend on then, i.e. there must be a reason the books are rendered differently? Is this because they are in different formats, i.e. EPUB and KEPUB?

From your first post I took it that you couldn't change the font size from the device? My suggestions about specifying font sizes in units of em instead of pt etc. and of avoiding the font: shorthand property are just because they can prevent the device from being able to change the font settings for the book.

Kepubs and epubs are read using different software, and so there will be some differences when you change from epub to kepub even if the book itself is identical. I believe the base kepub font size is a bit larger than for epubs, as kepub base margins are larger. I usually have to decrease the font size slider a few notches and reduce the margin slider one notch when I finish reading an epub and open a new kepub, but it also depends on the sizes set in the book.

If the device's font size adjustment slider is working, but you want all books to have the same base font size so you can avoid adjusting the font size on the device, then that can be done by rescaling all the font sizes in the book's stylesheet, but I would say it is a lot more effort than it is worth, Easier just to spend a few seconds adjusting the font size when you first open the book.

[JSWolf]

Originally Posted by GeoffR

From your first post I took it that you couldn't change the font size from the device? My suggestions about specifying font sizes in units of em instead of pt etc. and of avoiding the font: shorthand property are just because they can prevent the device from being able to change the font settings for the book.

Well, not with firmware 3.12.0. When I tried my test ePub using px to specify the font size, the H2O ignored it and rendered the text at whatever the font size was specified via the font size slider. So I don't know what's going on that would prevent the font size from being changed as it seem Kobo is ignoring the fixed size font specifications and rendering the non-fixed sizes.