[FFmpeg-devel] a64 encoder

Marc Mason mpeg.blue
Fri Jan 16 11:15:41 CET 2009

Vitor Sessak wrote:

> Here you could use just int [instead of uint32_t] (it will use just
> as much mem, since it will be mapped to registers anyway). Also, C99
> warrants that int has at least 32 bits.

This is not quite correct.

C99 requires
INT_MAX >= 32767
INT_MIN <= -32767

i.e. int must be at least ln(65535) / ln(2) = 15.999977986-bits wide.

POSIX however requires
INT_MAX >= 2147483647
INT_MIN <= -2147483647

i.e. almost 32 bits but most two's-complement systems will define 
INT_MIN to -2147483648


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