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ADV212 On low compression rates, each 4th frame is black

Question asked by gelke on May 3, 2011
Latest reply on Jun 9, 2011 by DaveD

Hello

We are using two ADV212 for decoding (encoding works fine) 1080i 25Hz and 30Hz. When we set the ADV to low compressio rates (>40mbit/s), each 4th frame will be output black.

We notice the following:

-The hold signal of the JDATA interface goes inactive when the black frame is output.

- If the "PRGRSV_SCN" bit in the vmode-register is set to 1 it works, but of course there is no synchronisation to the fields anymore

- The problem is only with 1080i, 1080p, 480i and 576i resolutions are fine.

- At high compression rates it works fine as well.

 

Thanks in advance for your help.

 

Andreas Bürkler & Hans Gelke

 

This is our configuration:

 

- Jdata interface
- custom specific mode
- video format YUV 422
- 2 chips
- in register "vmode", bit "PRGRSV_SCN" is set to 0 for interlaced
- slave mode, timing is extern generated (hsync, vsync, field)
- chips are synchronized with SWIRQ1 and SCOMM[5]

     // vertical (start with falling edge vsync)
     V0_REGION_ST    = 0
     V0_REGION_END   = 0xffff
     V1_REGION_ST    = 0
     V1_REGION_END   = 0xffff
     PIXEL_START_REF = 1
     PIXEL_END_REF   = 0
     YTOT            = 1125
     V0_START        = 16
     V0_END          = 555
     V1_START        = 579
     V1_END          = 1118
     F0_START        = 0
     F1_START        = 562

     // horizontal (start wirh rising edge hsync)
     XTOT            = 2640
     PIXEL_START     = 192
     PIXEL_STOP      = 2112

]

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