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IRT-Open-Source / scf

Subtitling Conversion Framework
Apache License 2.0
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STL2STLXML: mapping of TTI Blocks containing user data #28

Open pthopesch opened 7 years ago

pthopesch commented 7 years ago

In the current scf version 0.2.8, TTI blocks from an STL file that contain user data are ignored when transforming from STL to STLXML. To preserve user data (e.g. to allow for round-tripping scenarios) these TTI blocks should be mapped as well to the STLXML format. User data is signalled by an Extension Block Number (EBN) value of FEh. TTI blocks with an EBN set to a reserved value (F0h-FDh) should keep beeing ignored as described in requirement no. 208.

The content of the text field (TF) cannot be mapped (proprietary data) and thus should be encoded, e.g. using base64.

Extension Block Number (EBN): FEh --> TTI block contains user data Extension Block Number (EBN): F0h-FDh --> Reserved Codes

The description of the requirement no. 208 should be updated accordingly.

braincoded commented 7 years ago

+1 Yes, definately an important feature: (Lossless) round tripping is of high importance.

pthopesch commented 7 years ago

User data should also be mapped to from STLXML to EBU-TT (module STLXML2EBUTT).

andreastai commented 7 years ago

Currently the TTI user data is mapped to an element proprietaryUserData which is in "no namespace". The element should be qualified with a full namespace URI as introducing elements in "no namespace" may result in problems for further processing.

It may be a good idea to use something like the ebuttm:binaryData element.

spoeschel commented 6 years ago

Sorry; closed by mistake (internal issue ID)