Incorrect aspect ratio using MPEG-2 Decoder in the UMC samples

Pascal_Binggeli — Thu, 04 Mar 2010 15:05:47 GMT

Hello

I'm using IPP sample version 6.1.4.059.

I've found that the sample for the MPEG-2 decoder does not follow the ISO/IEC 13818-2 specifications for determining the sample aspect ratio. According to the 6.3.3 of the specifications, the aspect ratiomust bedeterminedfrom the sequence_display_extension()when this extension is present.

The implementation in MPEG2VideoDecoderBase::sequence_display_extension() simply ignore the display_horizontal_width and display_vertical_width, in umc_mpeg2_dec_pic.cpp, line 506:

GET_BITS_LONG(video->bs, 29, code)

should be replaced with

GET_BITS_LONG(video->bs, 14, display_horizontal_width)
SKIP_1BIT(video->bs)
GET_BITS_LONG(video->bs, 14, display_horizontal_height)

A consequence of this problem is that some clips are displayed using the wrong aspect ratio.

1. What is the correct way to report this issue for correction in future release ?
2. I'm wondering if this issue also affect the Intel Media SDK ?
3. Do I need to post in the Media SDK forum too ?

Cheers,
Pascal

Incorrect aspect ratio using MPEG-2 Decoder in the UMC samples

Chao_Y_Intel — Fri, 05 Mar 2010 06:36:08 GMT

Hi Pascal,

Thanks for posting here. We will track this problem, and fix it in the future release.

I think you can also post it in the MediaSDK forum if it also need to be fixed in that pacakge.

Regards,

Chao

Incorrect aspect ratio using MPEG-2 Decoder in the UMC samples

Chao_Y_Intel — Wed, 12 Jan 2011 15:16:18 GMT

This fix has already been included in the 7.0 package.

Thanks
Chao

topic Incorrect aspect ratio using MPEG-2 Decoder in the UMC samples in Intel® Integrated Performance Primitives

Incorrect aspect ratio using MPEG-2 Decoder in the UMC samples

Incorrect aspect ratio using MPEG-2 Decoder in the UMC samples

Incorrect aspect ratio using MPEG-2 Decoder in the UMC samples