EXTH Header Question

RecQuery · 06-07-2011, 03:23 AM

I'm tried searching but with no luck and I was wondering if anyone knows what the EXTH - 3 - drm_ebookbase_book_id header is and what's it used for?

Obviously from the name it's something DRM related, but every book I have has a different number, is it kind of like a DRM ISBN or what?

KevinH · 06-07-2011, 02:28 PM

Sorry but no one knows. There are actually 3 related extended header items (according to our own Wiki on the Mobi format)

1 drm_server_id
2 drm_commerce_id
3 drm_ebookbase_book_id

These are most probably involved in DRM generation and as you guessed possibly tracking. Once the DRM has been removed, you can typically change any of the metadata / exth header items including TTS, and the like.

06-07-2011, 03:23 AM	#1
RecQuery Junior Member Posts: 9 Karma: 10 Join Date: May 2011 Location: Scotland, UK Device: Kindle 3	EXTH Header Question I'm tried searching but with no luck and I was wondering if anyone knows what the EXTH - 3 - drm_ebookbase_book_id header is and what's it used for? Obviously from the name it's something DRM related, but every book I have has a different number, is it kind of like a DRM ISBN or what?

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06-07-2011, 02:28 PM	#2
KevinH Sigil Developer Posts: 7,630 Karma: 5433388 Join Date: Nov 2009 Device: many	Sorry but no one knows. There are actually 3 related extended header items (according to our own Wiki on the Mobi format) 1 drm_server_id 2 drm_commerce_id 3 drm_ebookbase_book_id These are most probably involved in DRM generation and as you guessed possibly tracking. Once the DRM has been removed, you can typically change any of the metadata / exth header items including TTS, and the like.

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