PPI reading Luminance (Y) data only from BT656 camera

Hi

Im trying to perform image analysis an a luminance only image which I want to record from a camera connected to the PPI and producing BT656 data. This outputs Y,C,Y,C ... data

Can I get the PPI to only record the Y data and throw the Chroma data way, or do I need to record both bytes and then copy (DMA step 2?) the image to another part of memory before I can work on it

Any suggestions would be helpful

Richard

  • Hi Richard,

    Sorry for the delayed response on this. Could you please confirm which processor you are using? Can you please elaborate on your setup?

    Best Regards,

    Jithul

  • Hi

    I think I have found a solution. Im using a BF707. I can see I can separate the Y and UV data in the PPI into two streams (odd/even) and use one or two DMAs to read. However I had hoped I could just read one stream and not bother reading the UV data but it appears i need to read both. 

    So in the end I used the PPI mode that combine 4 bytes of CR followed by 4 bytes of Y etc (SPLTEO=1, DMACFG=0) and used a 2D DMA to read the UV data into memory and then the Y data to the same address before incrementing it so overwriting UV data.

    Now if there was a way to only do one memory transfer rather than 2.....i.e. not bother reading the UV at all

    Richard

  • Hi

    I think I have found a solution. Im using a BF707. I can see I can separate the Y and UV data in the PPI into two streams (odd/even) and use one or two DMAs to read. However I had hoped I could just read one stream and not bother reading the UV data but it appears i need to read both. 

    So in the end I used the PPI mode that combine 4 bytes of CR followed by 4 bytes of Y etc (SPLTEO=1, DMACFG=0) and used a 2D DMA to read the UV data into memory and then the Y data to the same address before incrementing it so overwriting UV data.

    Now if there was a way to only do one memory transfer rather than 2.....i.e. not bother reading the UV at all

    Richard