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ADV212 in RAW pixel mode using the V-BUS and the J-BUS. Problems with over compression and poor decoding

Question asked by KobyW on May 8, 2017
Latest reply on May 8, 2017 by JeyasudhaMuthuPerumal

Hi, DaveD


I'm using the ADV212 in the RAW pixel mode using the V-BUS and the J-BUS. I'm compressing 256x256 tiles.  I encountered two disturbing phenomena:

  1. when compressing lossy (either 9/7 or 5/3 lossy) I get over compression (i.e. tiles are compressed to less than 1KB) regardless of configuration (0 - no truncation, 1 - cap with 0x2C00 or 2 - quality with 0x100). The only way I get good results is if I configure it to 1-5/3 lossless and to rate control with 0x2C00.
  2. when decompressing using SW I get better results than when decompressing with the ADV212 (compared using a diff between original and decompressed)



chip configuration:

for lossy encode:


for lossless wncode:


For decode:



I attached an example of a lossy and lossless codestream (note that I removed the ADV212 header).

It's a simple counter waveform