Custom Column for Cover Size

[Rellwood]

I have been searching all over to figure this out, even used Open AI, and it keeps giving me the wrong answer.

How do I create a custom column that has the cover size in a format like it's shown in the book details? My send to Kindle covers are not showing up in some devices and I want to make sure I also have the best size for showing on my scribe. I know the plugin for Quality check looks for covers of a specific size, but I just want a column to look over quickly.

Please and thank you for any help

[chaley]

There is no existing built-in way to get the cover size. It can be done in a python template but that requires opening the cover to compute its size, which could be too slow to use. What is "too slow" is up to you.

The template returns the cover size as "width by height". You can play with the formatting.

python:
def evaluate(book, context):
	db = context.db.new_api
	cover = db.cover(book.id, as_image=True)
	width = cover.width()
	height = cover.height()
	if width and height:
		return f'{str(width)} by {str(height)}'
	return '--'

Example output:

[chaley]

Using an actions chain to compute the size on-demand then store it in a text column removes the performance penalty. I imagine that a single-field-edit action with the above template would do the job.

[ownedbycats]

Originally Posted by chaley

Using an actions chain to compute the size on-demand then store it in a text column removes the performance penalty. I imagine that a single-field-edit action with the above template would do the job.

Instructions to install.

[ownedbycats]

It's not a huge issue as I'll probably be leaving the column hidden in tag browser, but is there a workaround the non-numerical sorting?

[chaley]

Originally Posted by ownedbycats

It's not a huge issue as I'll probably be leaving the column hidden in tag browser, but is there a workaround the non-numerical sorting?

Attachment 212520

There are two numbers. How do you expect it to sort?

Some thoughts:

• Turn on Preferences / Behavior / Recognize numbers insize text when sorting. This seems to sort on the first number, but it might take the second into consideration when the first are the same.
• Prefix the output with a "size" string such as "small, medium, large" or "Size 0" through "Size 9".
• Zero-pad the numbers to enough places, probably 4.

EDIT: Using this in the template zero-fills:

	if width and height:
		return f'{width:04d} by {height:04d}'

EDIT 2: The option doesn't seem to affect the tag browser.

[ownedbycats]

I mostly expected it to sort by the first number - I have the inline numbers option enabled. Could the lack of spaces in '123x123' be mucking it up?

[chaley]

Originally Posted by ownedbycats

I mostly expected it to sort by the first number - I have the inline numbers option enabled. Could the lack of spaces in '123x123' be mucking it up?

No. As I said in the above edit, that option doesn't seem to affect the tag browser. I'll look at that.

Zero-prefixing works, as would adding a string label that sorts the way you want

[chaley]

I found why "Recognize numbers" isn't working. If the partition method is set to "first letter" then "recognize numbers inside text" is ignored. This is correct behavior because first letter sorting is equivalent to alphabetic.

However, if partitioning is turned off for that field then "recognize numbers inside text" should be honored but isn't. I'm submitting a fix for this.

[ownedbycats]

Yeah, I had partitioning set to first letter but disabled. Thanks for fix.

[chaley]

The fix is now in calibre source.

[ownedbycats]

[Comfy.n]

Originally Posted by ownedbycats

Instructions to install.

When next Calibre version is released, I suggest anyone using this chain to do two things:

1 - add in Tweaks -> Plugin Tweaks:

action_chains_experimental = True

This is documented here: https://www.mobileread.com/forums/sh...postcount=1293

2 - Choose "Run chains in jobs" in the chain setup