MPEG2 Decoder Sample BUG ?!?!

[carles_b]

Hi everyone and sorry my english.

I'm testing the MPEG2Decoder IPP app. and I have found a bug with the files longer thant 1GB aprox. Well, the problem is in the bitstream.c, when the MapViewOfFile file on the BitstreamOpen function. When it fails it tryes to map it in blocks of 188 MB but only map one bloc. When this block finish no other block of the source file is mapped and the decoder finish.

Has everybody found any solution to this problem?

It is very easy to reproduce, changing the 188 MB of PORTION_SIZE by 2 MB (for example) the app. only map 2MB of the source file.

There are functions in the bitstream.c that allow to unmap and map a new block, but they never are called...

Thanks a lot

[JeromeDev]

Hi,

I also encountered several bugs in MPEG-2 decoder sample.
- the splitter is buggy. It may miss slices, because it reads data blocks, and cannot find slice start codes when they are across data blocks borders.
- some variables are not initialized, some functions don't return values whereas they should.
- P-field macroblock 4:2:0 decoding is not compliant (syntax issue in reading 'field_motion_type'), and may cause some video streams to crash the decoder.
- B-field and B-frame 4:2:0: same syntax issue. Also typos for B-field in some calls to ippiMC16x16B_8u_C1, ippiMC16x8_8u_C1, ippiMC8x4_8u_C1 lead to bad image reconstructions.
- I also noticed chroma reconstruction issues, but did not investigate further.

The official answer from Intel is: 'this code is not supported'.

Regards,
Jerome.

[Vladimir_Dudnik]

Hi,

we are going to renew this sample in the IPP v5.0 beta, which is coming soon.

Thank you for reporting this issue

Regards,

Vladimir

[gelbaerchen]

Hi, I also have crashes with some certain MPEG streams. I downloaded the sample yesterday so probably it's still the old version? When will the new sample be available? Will there be a sample without DirectShow where I can just input the PES-Videopackets as received from DVB and where the output is something like RGB frames? Thanks and best regards, Johannes

[Vladimir_Dudnik]

Hi,

yes you are right, it is still old version. The new sample will be released as a part of IPP v5.0 beta,the releaseis targeted to this summer.

Regards,

Vladimir