[FFmpeg-devel] [PATCH] avcodec/jpeg2000: use powf instead of pow

Michael Niedermayer michaelni at gmx.at
Wed Dec 9 10:21:10 CET 2015


On Tue, Dec 08, 2015 at 10:44:31PM -0500, Ganesh Ajjanagadde wrote:
> It may be entirely possible to optimize further by exploiting the fact
> that it is always an integer exponent. However, care must be taken since
> the base itself is not an integer, i.e a naive repeated squaring or
> similar such algorithm may be inaccurate.
> 
> Range information can only be obtained by knowledge of the spec, so the
> low hanging pow->powf is done.

this changes the decoder output (not vissible though)
http://ffmpeg.org/trac/ffmpeg/raw-attachment/ticket/1211/8bpp.jp2

also i think its better to have this at double precission

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Democracy is the form of government in which you can choose your dictator
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