Linux/TDA2: sxgFrmcpy and Display buffer : image data modify issue

Part Number:TDA2

Tool/software: Linux

Hi Sir,

My HW is TDA2x CPU board + Vision Board + daughter board + OV1652x sensor and SDK is PROCESSOR_SDK_VISION_03_04_00_00 with TDA2XX_EVM_LINUX_ALL define.

I select use-case "4CH VIP LVDS capture + SGX MOSAIC + DISPLAY" .

I changed the code like below steps:

1. I found the image capture buffer address in "SgxFrmcpyLink_drvDoProcessFrames" function, image point is "pVideoCompositeFrame->bufAddr[0][0]"

2. I try to modify the image data or clear data buffer in this function.

    ex.   compostive_video_buf_addr = pVideoCompositeFrame->bufAddr[0][0];

             memcpy(compostive_video_buf_addr, 0x00, 115200);

or 

 for (int i=0; i<57600; i++)

  compostive_video_buf_addr+i = 0xBBBBBBBBBBBBBBBB;

3. compiler and select use-case,

4.TV shows  a strange image, I attached the image file.

The image seems noisy and mix up the original capture image.

I have no idea whta's happen and how to fix it.

Ranny.