Is there a way to batch shrink CBR & CBZ files?

My Ipad Air is already filled with over 120 gigs of comics and manga. Is there any way to shrink the whole folder and or file sizes without having to do it file by file? Like a batch shrink? I'd love to fit all of my books, manga and comic files on my ipad but it's way over my size capacity. They're all mostly cbz and or cbr files. Any help would be of immense help!

cbr and cbz files are already compressed. What do you want to do to them? You coulds resize or recompress the JPEG images inside the archives to reduce space, but it could also affect image quality a lot, and may take a long time.

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I understand but right now my files are over 120 gigs and I want to reduce the size of them so that I can fit them all into my iPad. I don’t wanna have to do that file by file or individually tho. That’s a lot of files.

How do you want to reduce their size?

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Thanks for replying @Jon. The folders are 128 gig and 20gig. I want to be able to fit both on my Ipad Air but the size capacity is only 120 gig. I thought that there might be a way to do so and that's why I'm asking here. I'm not a programmer or developer, so I don't understand what your asking exactly to be perfectly honest :sob:. I just would like a means to put them on my Ipad staying under 120 gigs. I can't do so when its 148 gigs in total. There's ways to do it file by individual file but I just want to do it through batches.

There's ways to do it file by individual file but I just want to do it through batches.

How? If you tell us what it is you're doing to the individual files we might have a suggestion as to how to do it as a batch.

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I'm not currently using those methods to do that. It's the reason I signed up to this forum to ask people who might know. I searched all through Youtube and reddit for the answer to how to go about doing it. There's several programs that claim to do so but don't work for me all the years I've tried..


http://tomeko.net/software/CbxConverter/

Those are SOME of the links I've seen and googled. I was looking into Cbx convertor but the app I use on my Ipad, Total Reader, doesn't support those WebP formats. All the solutions that I found online were only about doing it file by file which would take forever. Do u have any experience using cbx convertor and if so, how can I use it to convert my files in batches?

Personally I don't know anything about shrinking CBZ files. Leo pointed out that it's unlikely to be possible because the files are already compressed, but you seemed sure it's possible. You'll need to do some research and work out exactly how this shrinking is done and then we can try and help you do it in batches.

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If the GBZ files are archives of JPG's You can use this library to reduce the image size without any noticeable loss (I use the smallfry setting).
You would need to first decompress GBZ file to the get images out, then smallfry the image and recreate the archive GBZ. In my exp smallfry reduces the image size by about 30%.

You would need to script it up thought.

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GBZ files? Or you mean CBZ? What Library? I don't know how to do any of the above let alone script. But thanks for the recommendation. To Jon @jon I tried that cbx convertor but it freezes up and wont let me convert anything. Its a program that shrinks book and comic book files (cbz, cbr etc) in batches. As I said earlier, it won't let me do it and when it does work, it can't handle more than one. It freezes up and restarts so I'm unable to use it on my computer. Again, I'm not a programmer so I wouldn't kno what else to provide you guys with. I know that cbr and cbz are just zipped files renamed. I saw this post a while ago and dmed the programmer but he hasnt responded as of yet.

How do I use this script? I'm not a developer at all... I downloaded Directory Opus but don't know how to implement this script and proceed with how to use it. Any help. Thank u everyone btw for responding.

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Thanks for the reply. I tried following it but this part in the instructions doesn't work:

  1. Back in the main window, right-click your toolbar somewhere and (depending on where you clicked) there will be a New or Insert New sub-menu. Click that sub-menu, and then New Button .

Are you using Opus Light or Pro?

I just switched to using Pro now. I wasn't able to do it in the Light edition. But I'm not sure what to do next. I wanna install this guy's button/script but not sure how. I got lost with the instructions.

Use the dcf file provided in the post you linked, and follow the "Button .dcf Files" part of the instructions I linked

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Thanks so much!! It worked. Now trying to figure out how to get it to work hahaha I want it to convert and replace the old files. Would u know how that works?

A CBR or CBZ file is a RAR or ZIP archive. Within an archive, files ususally are compressed already. So the only way to make them smaller is to re-compress them with a higher compression setting.

However, ComicBook Archives mostly consist only of bitmap images, which already are compressed with special algorithms, that work different to the ones used by the ZIP or RAR archivers. In this case, the archiver usually only stores those files without doing any compression by itself.

Recompressing bitmap images is possible. ComicBook fans tend to recompress JPEG into WebP, usually without visible losses. I did some tests myself and highly recommend it! The savings are astonishing!

However, since your reader software does not understand the WebP format, you are our of luck.

Here are some scripts, that help manage CBA files, though, they are not recompressors, just library management tools. Someone may be interested in them:

http://comicrack.cyolito.com/forum/13-scripts/10940-malor89-s-perl-scripts

This may be of interest to you: Comics: Convert CBR to CBZ

But as I said, the only real space saver would be to recompress the images into another format.

These links require a Windows OS.

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You can use the tool I posed above to re-compress a jpg files in to new jpg file without any noticeable loss. I usually find a get up to 30% size reduction.

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Thanks @wowbagger and @amix for the the advice. I dont have any problem using a different app and or using WebP but I'm a complete novice so I don't know how haha