EXTH Header Records differences

WEricBr · 06-09-2022, 01:46 PM

While looking into the EXTH Records types, I found that there are differences between what is documented in the Wiki, Calibre Headers.py file, KindleUnpack-DumpMobiHeader_v023.py.

The ones that are missing are easy to merge together, if I know which version is correct. However, there are a few that have different "names" for a given "type".

The Type Code/Type Name that don't match between at least 2 of the sources are:
131 , 405, 504, 508, 517, 522, 534, 535, 536, 538, 543

The ones that appear in DumpMobiHeader_v023.py but is missing in at least 1 of the other resources are:
4, 99, 150, 400, 405, 406, 420, 450, 451, 452, 453, 501, 502, 503, 504, 505, 506, 507, 508, 509, 510, 511, 512, 513, 514, 515, 516, 517, 518, 519, 520, 521, 522, 523, 526, 527, 528, 529, 530, 531, 532, 533, 534, 536, 538, 539, 540, 541, 542, 544, 599

The ones that appear in Calibre Header.py but not in the others are:
301

I have included a zip file that includes an Excel spreadsheet, HTML file and a tab-delmited file that contains a comparison the Type Values and Type Names from the 3 different sources to make it easy to see the differences.

Which of these should be considered the authoritative source?

Thanks,

Eric

JSWolf · 06-09-2022, 01:59 PM

#405 is the rented book flag.

jhowell · 06-09-2022, 03:37 PM

The most authoritative source I have seen so far is the HXDATA enumeration found in EpubToKFXConverter-4.0.jar which is a component of Amazon's Kindle Previewer software. That closely matches the names found in KindleUnpack other than differences in punctuation.

WEricBr · 06-09-2022, 04:59 PM

Is HXData a file within the jar or is it in a particular file that is within the jar file?

Thanks,

Eric

jhowell · 06-09-2022, 05:40 PM

Quote:

Originally Posted by WEricBr

Is HXData a file within the jar or is it in a particular file that is within the jar file?

It is data in a Java class inside of that jar file. In the most recent recent version of Kindle Previewer (3.65) it is in com/amazon/K/l/b$c.class.

WEricBr · 06-09-2022, 06:42 PM

Thanks. After installing java and a decompiler, and following your directions, I know have the HXData_* to compare to the existing EXTH Header Record type values from the other 3 resources.

Thanks again,

Eric

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06-09-2022, 01:59 PM	#2
JSWolf Resident Curmudgeon Posts: 79,760 Karma: 145864619 Join Date: Nov 2006 Location: Roslindale, Massachusetts Device: Kobo Libra 2, Kobo Aura H2O, PRS-650, PRS-T1, nook STR, PW3	#405 is the rented book flag.

06-09-2022, 03:37 PM	#3
jhowell Grand Sorcerer Posts: 7,073 Karma: 91577715 Join Date: Nov 2011 Location: Charlottesville, VA Device: Kindles	The most authoritative source I have seen so far is the HXDATA enumeration found in EpubToKFXConverter-4.0.jar which is a component of Amazon's Kindle Previewer software. That closely matches the names found in KindleUnpack other than differences in punctuation.

06-09-2022, 04:59 PM	#4
WEricBr Member Posts: 10 Karma: 10 Join Date: Jun 2022 Device: Kindle	Is HXData a file within the jar or is it in a particular file that is within the jar file? Thanks, Eric

06-09-2022, 06:42 PM	#6
WEricBr Member Posts: 10 Karma: 10 Join Date: Jun 2022 Device: Kindle	Thanks. After installing java and a decompiler, and following your directions, I know have the HXData_* to compare to the existing EXTH Header Record type values from the other 3 resources. Thanks again, Eric