[Ffmpeg-devel] Re: Intel IPP

[Ismail Donmez]

On Tuesday 15 November 2005 18:15, g. wrote:
> Tomas Christiansson <tomas.christiansson <at> gasoptics.com> writes:
> > Hi,
> >
> > Yes, we tried this (for MPEG2 decompression) last week using IPP 4.0
> > (Linux) and  managed to get an 8-9% speedup of the decompression (gcc
> > 3.3.4).
>
> Thanks for your quick reply.
>
> What CPU was that on?
>
> > Hopefully we'll be able to get more speedup when we move up to
> > IPP version 5.0. Below, you'll find patches (for
> > 'libavcodec/i386/dsputil_mmx.c' and 'configure') from our tests..
> >
> > What kind of linking are you using? Shared libraries or static? Which
> > IPP-version are you using?
>
> I'm using v5.0 (or at least, I'm trying to).
>
> I'm trying to use shared at the moment. I didn't get any static libs
> presumably because I simply downloaded the trial version.
>
> In the makefile of libavcodec I simply added -LIPP_PATH -lippi -lippcore
> but I keep on getting
>
> "In function `dsputil_init_mmx':
> dsputil_mmx.c:2608: undefined reference to `ippiDCT8x8Fwd_16s_C1I at 4'
> collect2: ld returned 1 exit status"
>
> I'm not sure what the "I at 4" suffix refers to, I simply tried to use
> ippiDCT8x8Fwd_16s_C1
>
> I used MinGW and the Windows version of IPP.

Did you adjust linker flags? You can check IPP demos on how to do that.

Regards,
ismail