concurrent transcodes on DSPC8681

Anuj Mittal

Hello

We're trying to run multiple channels of MPEG2 to H.264 transcodes using sv04, MCSDK video v2.2.0.45 on DSPC8681.

I can run multiple encode channels on the same chip. But, multiple decodes don't run on the same chip.

For example, I'm using cores 0, 1, 2, 3 & 4, 5, 6, 7 for encodes for two inputs. But, when I use 8 & 9 for MPEG2 decodes, it doesn't work. It works ok if I use 8 & 16.

I noticed that the changes to enable concurrent encodes on the same chip were integrated starting from SDK v2.2. Can you please point me to the changes that I need to make to enable multiple decodes as well? Is there a patch?

Thank you.

over 9 years ago

0 Paula Carrillo over 9 years ago

TI__Mastermind 32565 points

Hi Anuj,

In a quick inspection, It seems MCSDK video framework expects single core codec to use coreID=0 (0,8,16,24..). I will continue checking and let you know.

thank you,

Paula

0 Anuj Mittal over 9 years ago in reply to Paula Carrillo

Prodigy 230 points

Hi Paula,

I had checked this with the H.264 HP decoder too using 4 cores. But, that didn't work as well.

Thanks

Anuj

0 Paula Carrillo over 9 years ago in reply to Anuj Mittal

TI__Mastermind 32565 points

Hi Anuj, I think I found a bug in siuVctRun.c. I did a quick test with mpeg2 dec and it seems working now.
Please see attached files, please keep in mind that core0 need to be used for IPC.

siuVctRun.c

demoSave2File_multiChannel.sh

multiClip_ch1.cfg

multiClip_ch2.cfg

codecParams.cfg

thank you,

Paula

0 Anuj Mittal over 9 years ago in reply to Paula Carrillo

Prodigy 230 points

Hi Paula

Thank you for investigating this issue. I tried the file you've attached but that didn't work for me.

I've attached the log for demoSave2File.sh after making the change you've suggested. Only one output file is created.

Without the change, and cores as 0 and 8, two yuv files were being output as expected.

decodelogwithchange.txt

decodelogwithoutchange.txt

0 Anuj Mittal over 9 years ago in reply to Anuj Mittal

Prodigy 230 points

Any update here? Can you reproduce this problem?

Thanks.

0 Paula Carrillo over 9 years ago in reply to Anuj Mittal

TI__Mastermind 32565 points

Hi Anuj, apologize I missed your reply before, I will check this and update you soon.

thank you,

Paula

0 Paula Carrillo over 9 years ago in reply to Paula Carrillo

TI__Mastermind 32565 points

Anuj,

I downloaded MCSDK video 2.2.0.45 instead of using my engineering version in order to have a clean starting point.

when trying 2 Mpeg2 decoders in the same chip I was getting codec creation error. The issue is that core0 uses a bigger external memory than the other cores. Please change in siuVctMemMgr.c

EXTERNAL_DATA_MEM_SIZE_SLAVE from 0x0AE0000 to 0x0C60000

Also I noticed that in mpeg2dec codecParams "skip_B_frame" was set 1, please change it to 0.

With above changes I am getting 2 outputs however the are not correct. I am still checking the reason.

I additionally test it 2ch-single core Mpeg4 decoder it works OK, and 2ch-single H264HP decoder also worked OK (after changing in codecParams and demoSave scripts widht to 352 and height to 288 in order to avoid codec creation error and have to increase even further EXTERNAL_DATA_MEM_SIZE_SLAVE )

thank you,

Paula

0 Paula Carrillo over 9 years ago in reply to Paula Carrillo

TI__Mastermind 32565 points

Anuj, I forgot to mention after increasing EXTERNAL_DATA_MEM_SIZE_SLAVE you have to rebuild sv04

cd <mcsdk_video_path>\dsp\mkrel\ -> source setupenvMsys.sh -> make sv04

Also, the codec team is currently checking why MPEG2 dec output for multiple instance is not correct. We will update you soon.

thank you,

Paula

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concurrent transcodes on DSPC8681