[SOLVED] Batch convert MP3 tag inherent PNG cover data to JPEG

[Kalzifer]

OK, hear me out before posting a reply:

I'm using iTunes / iPod devices now for a very long time (I started archiving my musical fundus in iTunes in 2006) and have built up a vast iTunes library (more than 80.000 tracks) – and I love(d) the way, how they work seamlessly together.

Of course, hitting the limits of an iPod very soon this way (or merely: the limits of Apple's imagination of how big an iTunes library could get), I had to start juggling around with several iPods eventually.

Sadly, Apple stopped supplying (and supporting) these devices – and their phones form no alternative to me.

So I got myself recently a refurbished iPod with 512 GB memory and started experimenting with RockBox.

The Rockbox system has some really annoying limitations (when compared with iPod OS) - but it also "unlocks" several features that iPod OS never had and I'd be glad to switch and see it as a step into the future, but now I've encountered a really ugly problem:

Since iTunes 8 the apple software implemented cover artworks in PNG format - and RockBox won't display cover artworks in that format (you're getting a "blank" cover box when playing a track)...

I know, that I have to convert them into JPEG format and also figured out already, how to do that (and that it works) – but hey! as mentioned before I have now +80.000 songs to re-tag and that's a f§%king big load of work for me to do.

What I'm looking for is a solution (a program / an app / a script or whatever) that would batch convert the PNG files stored in my MP3s to JPEG format in any way that would save me from doing this all manually...

Maybe even extracting the PNG, saving it to disk, convert it externally and writing the "now JPEG information" back to the MP3 – whatever! ...as long I don't have to toil myself by doing it step by step, track by track, saluting every single little track with a personal handshake…

I don't wont to invest hours of work, simply because Apple lost it's interest in iTunes / iPods (or merely: it's users, since they moved on to economically more promising fields like streaming).

I'm just wondering if anybody else here hasn't made this (or a similar) experience and has already found out the solution or a workaround.

I have Mac and Windows machines at my hand to access the MP3s.

Any help greatly appreciated!

[philden]

On my Mac, I use an iTunes script to extract the art from each file and save it to a directory. Next I delete the embedded images using another iTunes script. I then use XnConvert to batch convert all of the images to a suitable format for Rockbox. I use .bmp files of the correct size for my preferred theme. I then manually copy each file to each album directory and rename them as 'cover.bmp'. I think I got the iTunes scripts from "Doug's Applescripts".

[Frankenpod]

Yup, Philden's suggestion sounds good.

  I recall I did something similar, though I think I used mp3tag (which can process things in bulk as well as individually) rather than iTunes scripts, and a different bulk art conversion program than XnConvert (but can't remember what it was now - I guess there are multiple such free programs around).

  Just extract them all en masse, then convert them all enmasse to jpg, then bulk re-embed the converted images (if that's what you want - could just leave them as cover.jpg in each directory).

[Kalzifer]

Although I thank you for your kind and quick responses, philden & Frankenpod, I'm afraid you may not have understood what I'm asking for.

I am familiar with the concept of a cover artwork saved seperately into a folder of MP3 files (like "folder.jpg" oder "cover.jpg") - but that's not what I'm trying to do.

I wish to implement the artwork information directly into to the MP3 tag information - for there is no other way, when you have stored MP3s of different albums into one and the same folder (e.g.: a collection of several single hits), to have their artworks displayed correctly when playing.

Earlier iTunes installments saved the cover artwork in JPEG-Format (as required by RockBox) into MP3s created with them - but after iTunes 8 Apple changed it's policy regarding this feature and from now on all cover artwork was implemented in PNG-Format, when creating (or modifying) MP3s with iTunes.

Here's an example of what I'm talking about:

1)


vs.

2)


I'm looking for an application, that can batch covert files from status 2) back to status 1).

[bahus]

there is no other way, when you have stored MP3s of different albums into one and the same folder (e.g.: a collection of several single hits), to have their artworks displayed correctly when playing.

You can have pictures specific to the file - just name it the same as filename (filename.{jpeg,jpg,bmp})

You can see rules how album art is loaded here: https://download.rockbox.org/daily/manual/rockbox-sansaclipzip/rockbox-buildap3.html#x19-435000C.2

[bahus]

And regarding batch converting. Not sure but TagScanner (for Windows) might be able to do it.

Update: Yeah it seems possible. I see option to Recompress (or resize) all cover arts. It should do it:

[philden]

I'm running iTunes 12 on my laptop, and some artwork is still embedded as jpegs. At least that is the format if I drag the image file out of the iTunes window to the desktop. So you might be able to do your conversion just with iTunes scripts. I'd make sure that your image files are not too big in rockbox, so that the software doesn't have too much processing to do. That is why I use .bmp files of exactly the right size for my theme, to reduce the processing load.

[Kalzifer]

Not sure but TagScanner (for Windows) might be able to do it.

YAAAAAAAH!!! 😱 This actually is working!!

One Million thanx to you, bahus! This was exactly the solution I was looking for - and TagScanner even is freeware!! 🥰

❤️ Thank you so VERY MUCH! ❤️  - i f there's anything how I might compensate you for saving me a hundred hours of "pain-in-the-ass" work, send me a DM!

[Kalzifer]

I'm running iTunes 12 on my laptop, and some artwork is still embedded as jpegs.

You're right, phildren - I guess it has something to do with the way I "work" with implementing cover artworks. Not mean to bore you - but since the days I began my library (in close connection to my very first iPod) I have a very strict procedure that I didn't stray from in now almost 18 years: I rescale any artwork that I'd like to implement to 170 x 170 px (as you can see in my screenshots above) which is the default size for a cover image on an iPod display.

I'm doing this usually via PhotoShop and COPY + PASTE the image via the clipboard - so iTunes is not the culprit, but the Apple system (maybe, in my beginnings in 2006 I still even used OS9...) which eventually switched the default image format in the clipboard from JPG to PNG.

Never mind now - since bahus provided the perfect solution for my problem. 😊

I'm looking forward now to become an enthusiastic RockBox user! 👍

[Kalzifer]

Now that I know what I'm looking for, I found out another solution for Mac Afficionados:

With MP3tag you can open a batch list of files, select them all, right-click on the cover artwork, select "Adjust" and a dialogue opens, where you can define artwork format, size and compression amount (for JPEG).



Just in case, that this maybe useful to anybody else...