DM36x JPEGenc: CustomQ vs Qvalue

Chris Meng

Hi,

My customer wants to use CustomQ. But it seems the output is still effected by the value of Qvalue. Is that true?

If yes, what's the relationship between the Q table used in codec and CustomQ/Qvalue? If I set Qvalue to 97 (max), does the the code use the q table in CustomQ without change?

over 13 years ago

0 Yashwant Dutt over 13 years ago

TI__Genius 17215 points

Which device/codec is this Chris ?

regards

0 Yashwant Dutt over 13 years ago in reply to Yashwant Dutt

TI__Genius 17215 points

Sorry, it seems the subject line had that info, will ask appropriate person to reply.

regards

0 Akshay Panday over 13 years ago in reply to Yashwant Dutt

Expert 1640 points

Hi Chris,

The DM365 will directly use the custom Q Matrix submitted by user. In a custom Q use case, the QValue parameter is ignored.

Regards,

Akshay

0 Chris Meng over 13 years ago in reply to Akshay Panday

TI__Mastermind 37646 points

Akshay,

Need we do below control call to set the CustomQ before process?

IMG_Control((IIMGENC1_Handle)handle, JPEGENC_TI_ENCODE_SETCUSTOMQ,
(IIMGENC1_DynamicParams *)&extn_dynamicParams, (IIMGENC1_Status *)&status);

0 Chris Meng over 13 years ago in reply to Chris Meng

TI__Mastermind 37646 points

Yashwant,

We made it work. We need to improve our JPEGenc user guide to add above info.

Processors

Processors forum

DM36x JPEGenc: CustomQ vs Qvalue