TDA4VM: Frame drop when using four 3840*2160 cameras

jingyu.zhang

Intellectual 260 points

Part Number: TDA4VM

i‘m tring to enable 4 cameras(AR0820 3840*2160) in multi-cam usecase with TDA4 SDK 7.2.

we are using max96712 as our Deserializer ,which has a fixed link rate of 6Gbps.

Based on bandwidth Serdes should support following cases:

case 1: 2 AR0820 raw 12 @27fps

case 2: 3 AR0820 raw 12 @18fps

case 3: 4 AR0820 raw 12 @13fps

when we actually run this case in application vx_app_multi_cam.out,data flow as capture->viss->aweb->mosic->display.

case 1 and case 2 works and no frame drop

case 3 works but actually fps is about 7fps and frame drop count increasing.

Can you help me analyze this problem

1) Is there any bandwidth limitation in TDA4's CSI or VISS?

2) should I change capture params laneBandSpeed , Now params is set by TIVX_CAPTURE_LANE_BAND_SPEED_1350_TO_1500_MBPS.

Best Regards!

over 5 years ago

0 Brijesh Jadav over 5 years ago

TI__Guru**** 501595 points

Hi,

I see frame drop for only channel0., is there possibility that there are more number of frames being sent for chnannel0 than other channels? Can you check if all channels of AR820 are configured correctly to send output at 13fps?

Regards,

Brijesh

0 jingyu.zhang over 5 years ago in reply to Brijesh Jadav

Intellectual 260 points

All channels are set at 13fps. channel mapping is correct.

0 Brijesh Jadav over 5 years ago in reply to jingyu.zhang

TI__Guru**** 501595 points

Hi,

It seems from the above stats, that channel0 is outputting more number of frames than rest of the channels. So average time is seen as 159ms, which is why fps is around 6fps.

I am still doubting that camera are not configured same. Can you please check camera configuration, especially for channel0?

Regards,

Brijesh

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TDA4VM: Frame drop when using four 3840*2160 cameras