PROCESSOR-SDK-DRA8X-TDA4X: LSC Issue

Raja Ram1

Part Number: PROCESSOR-SDK-DRA8X-TDA4X

Hi,

I generated LSC gains for IMX390 with input RAW image(1936 x 1086), with M = 64 and N = 64, so I got 576 entries for each channel and 576 * 4 gains in total. I filled the details in "tiovx/kernels_j7/hwa/vpac_viss/vx_vpac_viss_target_dcc.c", in "tivxVpacVissDccMapLscParams" as follows,

uint32_t grawfe_lsc_tbl[] =

{

#include "lsc_gains.txt"

};

lscCfg->enable = (uint32_t)TRUE;
lscCfg->gainFmt = RFE_LSC_GAIN_FMT_U8Q8_1;
lscCfg->horzDsFactor = RFE_LSC_DS_FACTOR_64;
lscCfg->vertDsFactor = RFE_LSC_DS_FACTOR_64;
lscCfg->tableAddr = grawfe_lsc_tbl;
lscCfg->numTblEntry = 576;

In this above settings I'm seeing only 1/4th of the image was shading corrected. Remaining 3/4th image are not proper.

But for the below settings if I changed the lscCfg->numTblEntry = 2304; (576*4 = 2304), then my image is 100% proper and shading corrected, is this the expected behavior?

over 6 years ago

0 Mayank Mangla over 6 years ago

TI__Mastermind 24525 points

Yes, this is the expected behavior. Because there are 4 color channels, the number of LUT entries has to be 4x.

0 Raja Ram1 over 6 years ago in reply to Mayank Mangla

Prodigy 180 points

Hi Mayank,

The max value of lscCfg->numTblEntry is limited to 4758. If I need to have a window size less than 64 then my entries will go beyond 4758.

Suppose for M=32 and N=16 for 1936x1086 resolution, 4278 locations with 4 gains each, then lscCfg->numTblEntry will be 17112 (4758*4).

But assigning lscCfg->numTblEntry = 17112; was giving error as max is limited to 4758.

How to have a lesser window size?

Thanks,

Raja

0 Brijesh Jadav over 6 years ago in reply to Raja Ram1

TI__Guru**** 501165 points

Hey Raja,

Yes, it looks like a bug in the driver. It should allow max 17112 (4758 * 4). In fact, the size of this memory is around 19KB.

Can you try changing value of the macro RFE_LSC_TBL_SIZE in the file pdk\packages\ti\drv\vhwa\include\rawfe_cfg.h?

Regards,

Brijesh

0 Raja Ram1 over 6 years ago in reply to Brijesh Jadav

Prodigy 180 points

Hi Brijesh,

I changed the macro RFE_LSC_TBL_SIZE to 19032U which is 4758*4, now I see the proper image.

Thanks,

Raja

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PROCESSOR-SDK-DRA8X-TDA4X: LSC Issue