[icu-support] Support for packed 7-bit character encodings

[Tim K. <KI...@uk...>]

I've recently encountered a character encoding that doesn't use octets, 
and is not byte-aligned. It is GSM-338 (
http://en.wikipedia.org/wiki/GSM_03.38#GSM_7_bit_default_alphabet_and_extension_table_of_3GPP_TS_23.038_.2F_GSM_03.38
).

a) is there any way to configure ICU to encode/decode GSM-338? 
b) if answer to a) is 'no', is there any prospect of support being added 
in a future release of ICU? 
c) how hard would it be for an ICU user to write an ICU encoder/decoder 
that operates on a bit stream instead of an octet stream, and supports 
GSM-338? Is there any documentation on 'rolling your own' ICU encoding? ( 
Apart from the documents that explain how to write data files to control 
the existing algorithms )

regards,

Tim Kimber, DFDL Team,
Hursley, UK
Internet:  ki...@uk...
Tel. 01962-816742 
Internal tel. 37246742

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