search

ietf-wg-cellar / matroska-specification

Matroska specification.
http://ietf-wg-cellar.github.io/matroska-specification
Other
120 stars 45 forks source link

Unknown schemaID #667

Open BilalBoulifa opened 2 years ago

BilalBoulifa commented 2 years ago

Hi everyone, I'm using the below library to parse mkv file info, it is a nodejs library https://github.com/oeuillot/node-matroska

the library uses the below ebml description defined in this repo https://github.com/ietf-wg-cellar/matroska-specification/blob/master/ebml_matroska.xml

and with certain mkv file I'm getting some unknown schema id, something not even defined in the official doc (https://www.matroska.org/technical/elements.html), below few examples, can someone explain to me what are these and how can I handle them?

Thank you

Unknown schemaID 0x8c tagId= 520 start=1329770 length=1 source= FileSource Unknown schemaID 0x6f80 tagId= 522 start=1345948 length=2 source= FileSource Unknown schemaID 0x39ff9bfc70966 tagId= 524 start=1348514 length=7 source= FileSource Unknown schemaID 0x55a7 tagId= 435 start=776491 length=2 source= FileSource Unknown schemaID 0x359b89 tagId= 436 start=776579 length=3 source= FileSource

robUx4 commented 1 year ago

Hi,

I can confirm those IDs don't exist. Can you share a file with these IDs ? It might be an error in the parser or some damage in the files. If the parser is broken you might also contact the developer(s) of the library.

Nice to hear more people are using the EBML Schema to parse Matroska elements :)

BilalBoulifa commented 1 year ago

they can be found even in files supposed to be samples provided by the official doc.

check the files provided in the below link: https://www.matroska.org/downloads/test_suite.html

and here what I found: 0x8c can be found on "test1.mkv" 0xa9 can be found on "test2.mkv" 0x4131 0x19050ba6 0x5275 0x50b2 can be found on "test3.mkv" 0xa0a0a0a0a can be found on "test4.mkv" 0x65ff can be found on "test5.mkv" 0xda 0x84 0x7af4 0xad 0x50e0 0x6c85 0x8f0e0fd48 0x349a46 0x4a79 can be found on "test6.mkv" 0x4001 0x1039c007 can eb found on "test7.mkv" 0x2c1295 0x5b70 0x2d54a6 0x7677 0x15530388 0x8495e759f 0xc2 0x7714 0x4634 can be found on "test8.mkv"