About 720x576 display have some serrated edges:
add L3.0.35_4.1.0_GA_bt656_output_patch_2017-03-10.zip pache.(https://community.nxp.com/servlet/JiveServlet/download/339528-1-418897/L3.0.35_4.1.0_GA_bt656_output...), 1) Support BT656(8 bits) and BT1120 (16 bits)interlaced output on display port.
uboot env set:console=ttymxc0,115200 init=/init vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale video_mode=extension video=mxcfb0:dev=bt656,BT656-PAL,if=BT656,fbpix=RGB565 video=mxcfb1:off video=mxcfb2:off fbmem=28M ldo_active=on
In ipu_disp.c BT656_IF_DI_MSB(23-->15):
+++ b/drivers/mxc/ipu3/ipu_disp.c
30
31 #define BT656_IF_DI_MSB 15 /* For 8 bits BT656: 23 for DISP_DAT23 ~ DISP_DAT16; 7 for DISP_DAT7 ~ DISP_DAT0 */
32 /* For 16 bits BT1120: 23 for DISP_DAT23 ~ DISP_DAT8; 15 for DISP_DAT15 ~ DISP_DAT0 */
I think you need check the TV encoder chip setting, the BT656 output signal aligns with BT656 specification, and it is digital signals.
please past more info ,
pin setting;and your hardware info
You can find the detail informaion from https://community.nxp.com/docs/DOC-94019
We had captured the BT656 frame data on 8 data lines and one clock line, make sure the frame aligns with BT656 specification.