h264 Encoder in 7.1 slower than in 7.0

[manca1]

Hi there,

I ported my H264 Encoder to IPP v7.1 using the samples that I built as dynamic multithreaded libraries and now the performance is dropped on H264 encoding with the same settings as in v.7.0.

Are you aware of the issues with h264 enc in 7.1?

I set m_iThreads to 0, and initialized the encoder correctly as well as the best ipp libs for my CPU using ippInit(). All my cores are used 100% when I am encoding something, but it's around 50-60% slower than it is when I do the same encoding with IPP v7.0 encoder. I am using separate threaded libs (which I download from the site). It's important to note that in v7.0, the usage of cores is around 40%, but still performs way faster than v7.1.

I tried v7.1 single threaded umc libs, as well, but they are way slower than the multithreaded ones.

Any help is really appreciated.

Thanks.

[Sergey_K_Intel]

Not yet ring. But we know which good version is. I will continue with reproducer. Please use good omp version for the present.

Regards,
Sergey 

[eliotlightcrafttech_]

We are also seeing a 30% speed fall between the 7.0 and 7.1 implementation of the h.264 *decode*. I suspect it is from the same libiomp5md.dll.

Have you reproduced this problem yet on the Intel side, and what is the ETA for a fix?

-Eliot

[Sergey_K_Intel]

Hi Eliot,

Do you have an idea where your problematic libiomp5md.dll came from ? From which Intel product ?

I would like to reproduce the issue locally, but for now everything's still ok, and I wonder if it is OK, because DLL is good, or it is OK, because the situation is not modelled correctly.

Regards,
Sergey 

[eliotlightcrafttech_]

Yes. The previous version of the libraries we used were:

w_ipp_7.0.4.196_intel64.exe and w_ipp-samples_p_7.0.4.054.zip.

The current versions are

 w_ipp_7.1.1.119_intel64.exe and w_ipp-samples_p_7.1.1.013.zip

We are now compiling with static linking in the new version.

-Eliot

[eliotlightcrafttech_]

Hi Sergey,

Were you able to replicate the slowdown with h.264 decoding with the two library/ipp samples versions that I mentioned?

-Eliot