topic Re: decoding mpeg2 by Media SDK in Media (Intel® Video Processing Library, Intel Media SDK)

decoding mpeg2 by Media SDK

kohshinToku — Wed, 30 Jun 2021 00:36:46 GMT

Hello.

My name is Tokunaga.

I inquired problem of Media SDK through EXEL Soft.
It is decoding of mpeg2 by Media SDK.

I hear that the inquiry number is #04949055.

Is there anything I can do here?

Regards.

Re:decoding mpeg2 by Media SDK

AthiraM_Intel — Wed, 30 Jun 2021 13:14:25 GMT

Hi,

Thanks for reaching out to us.

We are checking on it internally, will get back to you soon.

Thanks.

Re: decoding mpeg2 by Media SDK

Mark_L_Intel1 — Thu, 01 Jul 2021 03:07:09 GMT

Hi Tokunaga San,

Yes, I have contact XLSoft for the MPEG2 to reproduce the issue.

Again, I am apologized for the late response. Dev team started investigate this issue recently and they want to get the MPEG2 file to reproduce the issue. Since it was a while ago, I remembered the issue was reproducible with the data file after modifying the original sample.

Mark

Re: decoding mpeg2 by Media SDK

kohshinToku — Tue, 13 Jul 2021 04:41:28 GMT

Hi Mark.

Should I do anything about this problem?

Tell me if you want my help.

Regards.

Re: decoding mpeg2 by Media SDK

Mark_L_Intel1 — Wed, 14 Jul 2021 03:56:03 GMT

Thanks so much Tokunaga San,

Dev team is asking if you can send us the MPEG2 file to reproduce the issue.

I got your reproducer file in January and I submitted it to dev team. They want to use the MPEG2 file to reproduce.

Mark

Re: decoding mpeg2 by Media SDK

kohshinToku — Thu, 15 Jul 2021 05:01:16 GMT

Hi Mark

I sent a file that was used.

It is elementary stream of mpeg2.

If you have any questions, please ask.

Regards.

Re:decoding mpeg2 by Media SDK

Mark_L_Intel1 — Fri, 16 Jul 2021 07:37:00 GMT

Hi Tokunaga San,

Thanks so much for the quick response, I have send this to dev team and I will keep you updated.

Mark

Re: decoding mpeg2 by Media SDK

Mark_L_Intel1 — Tue, 20 Jul 2021 05:21:20 GMT

Hi Tokunaga San,

I checked your video and didn't see the noise strip you mentioned in the original document, but I did find some glitch like noise at the fix position, is this the issue?

I found 2 places at output and I have to slow down the playback rate:

sample_decode mpeg2 -i elementary_stream.img -r -f 25.

It is very small and quick, I found this artifact at 2 times from the output.

Mark

Re: decoding mpeg2 by Media SDK

kohshinToku — Tue, 20 Jul 2021 07:07:48 GMT

Hi Mark

Thank you for replay.

I think your point is different from my problem.

My problem arises when I split the elementaly stream into smaller pieces and feed them to the Media SDK.

The reason for this small division is that in my system data is transmitted via UDP over the network.
Your point would be packet loss that occurred during reception.

The previously sent data will be sent again.

Regards.

Re:decoding mpeg2 by Media SDK

Mark_L_Intel1 — Tue, 20 Jul 2021 07:21:23 GMT

"I split the elementaly stream into smaller pieces and feed them to the Media SDK", I understand better now. Can you describe how to split and why we need to change the original source file accordingly?

The problem is, if we input the split data as many data file as the package, we are not using it in a regular way. I am not quite familiar with MPEG2, but if you split it, is it still a normal stream?

Mark

Re: Re:decoding mpeg2 by Media SDK

kohshinToku — Mon, 26 Jul 2021 04:50:44 GMT

Hi Mark

We develop the decoder of monitoring system.

IP camera send the data through the local area network.

IP cameras send splited data to prevent fragmentation.

See

https://en.wikipedia.org/wiki/IP_fragmentation

about fragmentation.

The reason I changed Media SDK source, I tried to reproduce the phenomenon.

We couldn't reproduce the phenomenon at The long elementary stream.

I am attaching the packet data sent from the IP camera for your reference.

Regards.

Re: Re:decoding mpeg2 by Media SDK

kohshinToku — Mon, 26 Jul 2021 05:00:30 GMT

if (pBS->DataLength == 1) {
memmove(pBS->Data, pBS->Data + pBS->DataOffset, pBS->DataLength); ------ break point
}
else {
memmove(pBS->Data, pBS->Data + pBS->DataOffset, pBS->DataLength);
}

I wanted to point that DataLength is 1 sometimes at splited data.

I checked it by setting break point.

Re:decoding mpeg2 by Media SDK

Mark_L_Intel1 — Mon, 26 Jul 2021 19:54:39 GMT

Hi Tokunaga San,

I can't validate from your answer if this modification changes Media SDK requirement or not.

My question was, if you want to supply the data files instead of MPEG2 stream, it must be satisfied with MPEG2 standard; in other words, the bitstream represented by these files must be a standard MPEG2 steam. If it is not, this would be out of the current Media SDK requirement, dev team can't trade it as a bug.

Mark

Re:decoding mpeg2 by Media SDK

Mark_L_Intel1 — Tue, 27 Jul 2021 00:51:29 GMT

Hi Tokunaga San,

Dev team sent me an update saying they have reproduced it based on your original package. I will keep you updated with any progress.

Mark

Re:decoding mpeg2 by Media SDK

Mark_L_Intel1 — Wed, 11 Aug 2021 04:26:48 GMT

Hi Tokunaga San,

Some update, dev team had identify the issue at the frame level and they found some clues on which code causes the problem, still waiting for the further analysis.

Mark

Re:decoding mpeg2 by Media SDK

Mark_L_Intel1 — Thu, 12 Aug 2021 03:49:35 GMT

Hi Tokunaga San,

Dev team has found the root cause: data_0027.bin end with 00 00 01 07, data_0300.bin end with 00 00 01 09, both are slice start-code, which indicates the 7th slice and 9th slice in the current frame. But MSDK lib skips these four bytes and then skip the related slice, cause the noise in the frame.

This was caused by the code merge by mistake. We will fix it in Media SDK library. But there might be a deployment issue since we only have one release a year, how urgent do you want this fix?

Mark

Re: Re:decoding mpeg2 by Media SDK

kohshinToku — Thu, 09 Sep 2021 00:20:19 GMT

Hi Mark.

Sorry for the late reply.
I had Covid-19 and was in the hospital for 20 days. True story.

Thanks for the research on the issue.

- I hope to have it fixed as soon as possible as it is an important issue for my company.

- Could you please give me a test version of the product so I can see if the fix matches the problem I am having?

Regards.

Re:decoding mpeg2 by Media SDK

Mark_L_Intel1 — Fri, 10 Sep 2021 06:01:59 GMT

Wow! If you didn't tell me this is true story I would think this is a joke. This is the first time someone tell me he had it!

I heard this COVID-19 is not easy to recover so let me pray for your full recovery.

I had some good news for you, dev team told me they had a fix and they send me the package. I will try it first to see if it work, once confirmed, I will send you.

I have other tasks recently, so please allow me for 1 week.

Mark Liu

Re: Re:decoding mpeg2 by Media SDK

kohshinToku — Mon, 04 Oct 2021 07:31:24 GMT

Hi Mark

Unfortunately my lungs seem to be a little damaged.
However, I am trying to recover to a level that is not a problem in my daily life.
Please be careful not to get this virus.

I am waiting for your fixed version.

Regards.

Re:decoding mpeg2 by Media SDK

Mark_L_Intel1 — Mon, 04 Oct 2021 19:08:21 GMT

Hi Tokunaga San,

Thanks for the reminder and apology for the delay.

Since this is a library fix and we are not in new release cycle, we will build a special package for you to check first. Let me get the package ready and send to you.

Mark