topic Re: Bug in H.264 encoder in Intel® Integrated Performance Primitives

Bug in H.264 encoder

Emmanuel_W_ — Mon, 21 Sep 2009 12:14:40 GMT

It seems there is a bug while encoding chroma components in the H.264 encoder.

The function H264CoreEncoder_EncodeChroma encode in one shot both the U and V components. It starts with the U and upon reaching the first block of the V components switch pointers to the V plane. However, the condition to switch components doesn't seem right and upon reaching block 2 of the V components the U pointer are used again.

Emmanuel

Re: Bug in H.264 encoder

Vladimir_Dudnik — Thu, 24 Sep 2009 17:46:33 GMT

Hello Emmanuel,

thanks for reporting on this. Could you please specify what version of IPP do you use? Just worrying if you had a chance to try the latest IPP 6.1 update 1 version?

Regards,
Vladimir

Re: Bug in H.264 encoder

Emmanuel_W_ — Thu, 24 Sep 2009 18:06:23 GMT

Quoting - Vladimir Dudnik (Intel)

Hi Vladimir,

I have IPP 6.1 update 1 and latest sample version.

Emmanuel

Re: Bug in H.264 encoder

Vladimir_Dudnik — Thu, 24 Sep 2009 18:11:51 GMT

Thenks, I'll pass this information to development team.

Vladimir

Re: Bug in H.264 encoder

Leonid_K_Intel — Fri, 25 Sep 2009 10:05:30 GMT

Emmanuel, the "do" loop has only 2 iterations, so that uBlock is first U (==16) at first and then firstV (==16+num_blocks[chroma]) at second time. There are few different block loops inside do{}, like

for (uBlock = startBlock; uBlock < uLastBlock; uBlock ++)

Regards,
Leonid

Re: Bug in H.264 encoder

Emmanuel_W_ — Fri, 25 Sep 2009 12:39:55 GMT

Quoting - Vladimir Dudnik (Intel)

Thenks, I'll pass this information to development team.

Vladimir

Sorry for the fast alarm. I have modified this part of the code on my side and though I was looking at the original Intel code.

Emmanuel