Re: [boost] Any interest in bitstream class?

Subject: Re: [boost] Any interest in bitstream class?
From: Paul A. Bristow (pbristow_at_[hidden])
Date: 2013-06-29 08:06:22

> -----Original Message-----
> From: Boost [mailto:boost-bounces_at_[hidden]] On Behalf Of Adam Wulkiewicz
> Sent: Saturday, June 29, 2013 12:43 PM
> To: boost_at_[hidden]
> Subject: Re: [boost] Any interest in bitstream class?
> 
> Hi,
> 
> Paul Long wrote:
> > What do you think?
> > Should the bitstream library support multiple endian schemes in the
> > bit stream or is big endian enough?
> >
> 
> Various communication protocols or files may define the endianess of data differently. There are
even
> cases like TIFF files which define the endianess of data in the header. Therefore this type of
library should
> support different endianesses. It should also probably support switching them for the same stream
> multiple times. E.g. some manipulators could be
> provided:
> 
> namespace bs = boost::bitstream;
> 
> mystream >> bs::big >> my_int16 >> my_IEEE754_float_32 >> bs::little >> other_int16;
> 
> Of course the endianess of variables on a specific platform should be taken into account.
> 
> It could also support some non-C++ formats like 16-bit half precision or 128-bit quad precision
floats.
> Some typedefs would probably be required in namespace boost::bitstream.

A proposal for floating-point typedefs 

http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3626.pdf

may provide some help - eventually ;-)

For example:

"Specifying 128-bit precision

The proposed typedef float128_t provides a standardized way to specify quadruple-precision
(Quadruple-precision floatingpoint format) in C++."

Paul

---
Paul A. Bristow,
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