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pini · 09-23-2011, 05:59 AM

Alas,

no luck here!
Last week I've been trying to get some comics on my PB903 and using testing Calibre for conversions. Too many options and I'm not satisfied yet. I'll explain what I want and what I tried and what (doesn't) work. (ANd more testing to do!)

Please, prove me wrong!

The input
I have a few Gigs of high-quality (I think, I'm not a connaisseur, something like 2500x1500, full colour) comics series. I used Calibre to convert them to pdf and epub, playing around with settings like colour-depth, b/w settings and resolution, but I'm not satisfied with the results. AND: Calibre is slow in these conversions of ~40MB files (up to minutes for 1 book!)
[I do like Calibre though!]

There isn't a cbr/cbz reader for the pocketbook.
One can copy a CBR/CBZ archive to the PB by tricking calibre or just using a filebrowser. I tried fooling the PB telling it to open CBR/CBZ with CoolReader, but It can't. should I try any other reader (FB, PDF?). The rationale to try this, is that a CBR/CBZ archive is just an archive like EPUB.

I am Lazy,
so I want to do any copying or conversions using Calibre.

Just use the picture-viewer
This is actually a great option!; just unzip or unrar your archive and hard-copy the directory to the PB. No tricks needed to open the files; images are scaled properly automatically and so far the quality is the best I've seen. full colour and colour depth reduction (16 shades of Gray for PB) are no problem. most strips look beautiful and have great contrast. Paging is fast.
Danger
IF the images inside the archive are NOT numbered alphabetically or in such a way the image viewer reads them in the proper order, you're lost
So why not use this option? well, I'm lazy and don't want to do the unzipping and copying manually, though you could probably write a VERY simple plugin for Calibre to do this for you.
HINTHINTHINT !!! Who can do this?!

A good thing (involving even more steps, unless a plugin would take over) is that you can convert the CBZ/CBR to epub, do image resampling (lower resolution, use sharperning, reduce colour depth to reduce file size) and THEN copy the individual image-files in one directory to your PB. would this also save the file-pagenumbering problem??? I feel no need to do this with 8 GB on an SD card, but this way I discovered that these files are fine and that rendering of the epubs by the PB readers actually sucks.

Oh, and your PB can't remember your last page in the image directory. some kind of index file might do the trick, but then we'd be reinventing .CBR or epub I guess.

Calibre is SLOW I've tried quite some conversion options, but must admit I only did this on a handful of comics, so no guarantee it works for other books! But I can guarantee you it is SLOW!
* sharpening
* colour depth 16/256
* keep ratio
* turn comics conversion OFF
* keep colour
More inportantly, I tried some different 'target e-readers' (PB is not there), to get all kinds of resolutions. Irex1000 worked best for me until now as it creates files of around 1150x900.

This is important, because one of the things I am dissatisfied with, is that most epubs didn't use the full screen. This partly has to do with the ratio of the pages of course.
I haven't tried all combi's (too slow), but resolution is important (obviously), the other options seem to matter a lot less, but can reduce files size considerably.

Bigger problem is that the result on screen is UGLY. I tried CoolReader, FBreader. They don't use the page well, don't even center the page. very ugly rendering, lots of moiree etc. Best options seemed to be actually ADOBEreader (on epubs!), but is zoomes-in a bit too far, loosing some of the borders of the actual image. I can NOT zoom like you can with a pdf file. Rendering is best after the picture-viewer, really nice to see!

Just convert to PDF
Using Calibre again, this works fine. Again, you can change the image resolution, but the default are not appropriate for your large screen, so choose a bigger target reader or disable all comics-specific conversions.
Apart form slow Calibre, I wasn'nt very satisfied with the reading quality in pdfreader or Adobe. But it is workable.

ANy surprises here?

some conclusions:
It must be possible to have a real nice rendering and thus Good and pleasant reading experience on the large PB screen, from experience with the picture viewer
Calibre is useful for conversion and automation, but needs a proper plugin for ideal settings and PB resolution and MAYBE all the magic is in the epub html or css files and these can be tweaked to actually show the images properly!

use the idea's that you like and please let me know If you find a(nother/better) solution, program, plugin?

cheers,

pini

09-23-2011, 05:59 AM	#9
pini Member Posts: 18 Karma: 10 Join Date: Jun 2011 Location: Wageningen, The Netherlands Device: PocketBook Pro 903, iPod touch	Pocketbook, comics reader & Calibre Alas, no luck here! Last week I've been trying to get some comics on my PB903 and using testing Calibre for conversions. Too many options and I'm not satisfied yet. I'll explain what I want and what I tried and what (doesn't) work. (ANd more testing to do!) Please, prove me wrong! The input I have a few Gigs of high-quality (I think, I'm not a connaisseur, something like 2500x1500, full colour) comics series. I used Calibre to convert them to pdf and epub, playing around with settings like colour-depth, b/w settings and resolution, but I'm not satisfied with the results. AND: Calibre is slow in these conversions of ~40MB files (up to minutes for 1 book!) [I do like Calibre though!] There isn't a cbr/cbz reader for the pocketbook. One can copy a CBR/CBZ archive to the PB by tricking calibre or just using a filebrowser. I tried fooling the PB telling it to open CBR/CBZ with CoolReader, but It can't. should I try any other reader (FB, PDF?). The rationale to try this, is that a CBR/CBZ archive is just an archive like EPUB. I am Lazy, so I want to do any copying or conversions using Calibre. Just use the picture-viewer This is actually a great option!; just unzip or unrar your archive and hard-copy the directory to the PB. No tricks needed to open the files; images are scaled properly automatically and so far the quality is the best I've seen. full colour and colour depth reduction (16 shades of Gray for PB) are no problem. most strips look beautiful and have great contrast. Paging is fast. Danger IF the images inside the archive are NOT numbered alphabetically or in such a way the image viewer reads them in the proper order, you're lost So why not use this option? well, I'm lazy and don't want to do the unzipping and copying manually, though you could probably write a VERY simple plugin for Calibre to do this for you. HINTHINTHINT !!! Who can do this?! A good thing (involving even more steps, unless a plugin would take over) is that you can convert the CBZ/CBR to epub, do image resampling (lower resolution, use sharperning, reduce colour depth to reduce file size) and THEN copy the individual image-files in one directory to your PB. would this also save the file-pagenumbering problem??? I feel no need to do this with 8 GB on an SD card, but this way I discovered that these files are fine and that rendering of the epubs by the PB readers actually sucks. Oh, and your PB can't remember your last page in the image directory. some kind of index file might do the trick, but then we'd be reinventing .CBR or epub I guess. Calibre is SLOW I've tried quite some conversion options, but must admit I only did this on a handful of comics, so no guarantee it works for other books! But I can guarantee you it is SLOW! * sharpening * colour depth 16/256 * keep ratio * turn comics conversion OFF * keep colour More inportantly, I tried some different 'target e-readers' (PB is not there), to get all kinds of resolutions. Irex1000 worked best for me until now as it creates files of around 1150x900. This is important, because one of the things I am dissatisfied with, is that most epubs didn't use the full screen. This partly has to do with the ratio of the pages of course. I haven't tried all combi's (too slow), but resolution is important (obviously), the other options seem to matter a lot less, but can reduce files size considerably. Bigger problem is that the result on screen is UGLY. I tried CoolReader, FBreader. They don't use the page well, don't even center the page. very ugly rendering, lots of moiree etc. Best options seemed to be actually ADOBEreader (on epubs!), but is zoomes-in a bit too far, loosing some of the borders of the actual image. I can NOT zoom like you can with a pdf file. Rendering is best after the picture-viewer, really nice to see! Just convert to PDF Using Calibre again, this works fine. Again, you can change the image resolution, but the default are not appropriate for your large screen, so choose a bigger target reader or disable all comics-specific conversions. Apart form slow Calibre, I wasn'nt very satisfied with the reading quality in pdfreader or Adobe. But it is workable. ANy surprises here? some conclusions: It must be possible to have a real nice rendering and thus Good and pleasant reading experience on the large PB screen, from experience with the picture viewer Calibre is useful for conversion and automation, but needs a proper plugin for ideal settings and PB resolution and MAYBE all the magic is in the epub html or css files and these can be tweaked to actually show the images properly! use the idea's that you like and please let me know If you find a(nother/better) solution, program, plugin? cheers, pini