[FFmpeg-devel] [PATCH] AAC: type puns for 16 bit floating point rounding

Måns Rullgård mans
Tue Dec 9 12:02:23 CET 2008

Robert Swain wrote:
> 2008/12/5 M?ns Rullg?rd <mans at mansr.com>:
>> Uoti Urpala <uoti.urpala at pp1.inet.fi> writes:
> [lots of arguing]
> So, where are we with this?

The type punning using unions is defined by the latest version of the C
spec, and it seems to work with most compilers.

Two questions remain to be answered for each platform:

1. Does it use IEEE754 floating-point format?
2. Is the hack faster than using normal float operations?

We know 1 to be true for everything we're ever likely to encounter.
2 needs to be tested.

M?ns Rullg?rd
mans at mansr.com

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