View Full Version : MobiDeDRM for .prc files


bringer666
02-05-2009, 06:45 PM
I have an iPhone and some books that I've purchased from Fictionwise that are in secure MobiPocket format. I am trying to use MobiDeDRM to take out the DRM so I can use Stanza to read the books. I have been able to run MobiDeDRM successfully (or so it seems) using the line:
mobidedrm.py book.prc book_nodrm.prc ID#
The ID# is the one that I have in my Palm version of Mobi reader which is used by the program to encrypt the book. The conversion does not error out and I get a file at the end that is the same size as the original.
When the conversion is done I have tried opening the book in the Windows Stanza reader (so I can share it and put it on my iPhone) and when the program tries to open the book, I get the error:
java.lang.ArrayIndexOutOfBoundsException: 1420

Can anybody help me figure out what the problem is? I am using version .05 of MobiDeDRM.

AnemicOak
02-05-2009, 07:33 PM
Does it open in Mobi's desktop software? I'd try that to rule out a Stanza problem.

wallcraft
02-05-2009, 08:31 PM
Try using Calibre to convert the MOBI to ePub. On the command line: any2epub file.mobi or use the GUI.

bwaldron
02-05-2009, 11:28 PM
Does it open in Mobi's desktop software? I'd try that to rule out a Stanza problem.

I second that advice. The desktop version of Stanza isn't the best reader, and the problem may be with it rather than the ebook.

bringer666
02-06-2009, 12:25 PM
I was able to open the file in the Mobipocket reader. I used Calibre to convert the file into epub format and then I was able to open this file in Stanza and then was able to transfer it to my iPhone and it looks great.

Thank you very much everybody for your help.

viiiupndhead
04-06-2009, 10:20 PM
I had the same problem with Stanza. If you are trying to convert a Mobi book to read on a Mac do the following.

1. Download this zip file: LINK REMOVED

2. Run the applescript to remove the DRM

3. Download Callibre

4. Convert the unlocked file into an epub file.

5. You can then view it with Stanza or use stanza to convert it to something else.

delphidb96
05-07-2009, 07:11 PM
When I try to de-DRM a .prc file, I'm getting that error upon running MobiDeDRM. I 'think' this means it hasn't been encrypted - am I correct?

(I'm asking because I just used iPhone Backup Extractor to remove a Kindle .azw ebook from my iPhone and the Kindle ebook *should* have been DRM-laden as it was purchased, by me, through Amazon.)

Derek

wallcraft
05-07-2009, 07:15 PM
When I try to de-DRM a .prc file, I'm getting that error upon running MobiDeDRM. I 'think' this means it hasn't been encrypted - am I correct? Yes. Just rename it from .azw to .mobi or .prc and any MOBI Reader will display it.

(I'm asking because I just used iPhone Backup Extractor to remove a Kindle .azw ebook from my iPhone and the Kindle ebook *should* have been DRM-laden as it was purchased, by me, through Amazon.) Almost all AZW ebooks originally submitted through Amazon's DTP are DRM-free. All the AZWs originally submitted through mobipocket.com have DRM. Another rule of thumb is that major publishers use DRM, independent authors submitting their own stuff generally don't.

delphidb96
05-07-2009, 07:38 PM
Yes. Just rename it from .azw to .mobi or .prc and any MOBI Reader will display it.

Almost all AZW ebooks originally submitted through Amazon's DTP are DRM-free. All the AZWs originally submitted through mobipocket.com have DRM. Another rule of thumb is that major publishers use DRM, independent authors submitting their own stuff generally don't.

Now ONE of the books gave me an Invalid File Type (Format?) error. Is that a DRM'd one? And any ideas on how to use MobiDeDRM on it? It, too, was purchased through Amazon and works FINE on my iPod Touch. Of the three I purchased through Amazon, it is the only one that Mobipocket Reader *won't* open and it's a friggin' 3.7MB file size!

BTW, all three showed up as .prc on the iPod Touch when I ran iPhone Backup Extractor. And they show the .prc extension even under WinXP - not .azw.

Derek

phenomshel
05-07-2009, 07:55 PM
Thank you Derek! That answered an important question for me :)

wallcraft
05-07-2009, 07:59 PM
Now ONE of the books gave me an Invalid File Type (Format?) error. Is that a DRM'd one? And any ideas on how to use MobiDeDRM on it? It, too, was purchased through Amazon and works FINE on my iPod Touch. This means that it isn't a BOOKMOBI file (Wiki: PDB (http://wiki.mobileread.com/wiki/PDB)), so it is probably a TOPAZ file. These start with the letters TPZ, and they are not in Palm PDB or PRC format. These can't be decrypted with mobidedrm.

TOPAZ ebooks tend to be large, because they contain bitmaps in six sizes of the fonts they use.

phenomshel
05-07-2009, 08:55 PM
Drat, drat, and drat again! I was hoping this would prove to be a workaround to be able to format shift Topaz files. Guess not.... "curses, foiled again..."

delphidb96
05-08-2009, 02:49 AM
Drat, drat, and drat again! I was hoping this would prove to be a workaround to be able to format shift Topaz files. Guess not.... "curses, foiled again..."

Yep. I just confirmed it with Hextreme. My Kindle edition of "The American Zone" is in .tpz format even though it was given the same .prc extension as the two BOOKMOBI Kindle ebooks, "Hope" and "Tom Paine Maru". Damn! The iPod Touch (8GB) does NOT handle 3.8MB ebooks in .tpz format very fast! It runs about 3-4 seconds to decrypt each PAGE!

Derek

wallcraft
05-08-2009, 10:42 AM
My Kindle edition of "The American Zone" is in .tpz format even though it was given the same .prc extension as the two BOOKMOBI Kindle ebooks, The use of .prc is presumably some iPhone filetype recognition kludge, either to allow downloading to the iPhone or to bind the files to the Kindle Reader app. The app started out as a Mobipocket Reader (by all accounts), so Amazon probably slapped TOPAZ processing on the side without changing the filename extension logic.

dangkict
05-11-2009, 11:19 AM
Hi Everyone,
Sorry to cut in. I dont want to make a new thread.
Also, I did search around, but maybe not using the correct key words.
Could anyone can help to answer why I can't use mobi2html for this below file http://www.mediafire.com/file/q2i5wgez32m/Tap 01 - Thu pham tang hinh.prc
1) Currently, I can read this file on my Mobile, but the font is not very correct,
2) I intend to do some font conversion, which need to extract the file to HTML, convert the Font then save back as PRC
3) I get my device PID by using Mobipocket Reader -> Reading Devices -> Properties
4) I found that this is DRM-ed, so I'm try to use MobileDeDRM 0.5 with my PID, but it told me "Error: no key found. maybe the PID is incorrect"
What should I do?

Thanks for all the help.
Regards.

wallcraft
05-11-2009, 11:38 AM
Could anyone can help to answer why I can't use mobi2html for this below file I suggest deleting the link, since you probably don't have the right to distribute the ebook.

Three possibilities: a) ebook is DRM-free but uses MOBI-specific compression, b) MOBI is "content encrypted", c) your PID is entered incorrectly on the mobidedrm command line.

For (a), try importing the file into Calibre and reading it. If you can read it, then convert to ePub using Calibre (ePub is just a ZIP file, unzip - edit - rezip - convert back to MOBI).

For (b): MOBI has a DRM mode where there is no PID but the ebook is encrypted and can only be read by MobiPocket's own Reader. See Content Encryption (http://www.mobileread.com/forums/showpost.php?p=425158&postcount=32).

If (c) then there are other threads giving advice, but the fist thing to try is put all arguments in quotes (single quotes on the Mac). You could also try pid_checksum.py (http://www.mobileread.com/forums/showpost.php?p=317502&postcount=233).

dangkict
05-13-2009, 08:16 AM
I suggest deleting the link, since you probably don't have the right to distribute the ebook.


hi WallCraft, thank you very much for your advice.
Dont worry, this ebook is freely distributed.
I can read it on my PC and the other 2 devices.
For your advices:
a) I can't read using Calibre, it told me; "This book is protected by DRM".
c) Always tell me wrong PID
b) IT WORKS

Thank you very much :thanks:
You are de man :thumbsup:

Edit: For my case, my device always display some characters in SQUAREs (I'm not using English)
My solution is to convert to HTML, delete all Fonts Face, then convert back to PRC,
Cheer

Reddevil
05-24-2009, 05:10 AM
Hi Everyone,
4) I found that this is DRM-ed, so I'm try to use MobileDeDRM 0.5 with my PID, but it told me "Error: no key found. maybe the PID is incorrect"
What should I do?

I was getting the same error using my mobipocket PID until I renamed the .prc file I was trying to remove the DRM off to something simple like blah.prc. Try taking any spaces/underscores/or any other symbols out of the file name.

Post 72 (http://www.mobileread.com/forums/showpost.php?p=468690&postcount=72)

I knew my PID was correct and I was running the script properly, when I tried my PID in quotes it just said invalid checksum.. took me a good 2 hours to figure the underscore in the prc file thing out.