DRA744: How offset, the picture data to be displayed

The bpp for NV12 , 4-2-0 what should it be?


What change should I do to change the image on LCD  from 
        
to

Hi Ajith Johnson,

Are you able to display first image? Then for the second image, you just need to change the start offset to somewhere in the picture. No need to change other parameters..

Regards,

Brijesh

Sorry, by my question, is how is this offset calculated? Is there any dependency on picture formats.
Also, reiterating Is DISPC_VID1_ROW_INCREMENT related to this?

Again, if it is working fine for the first image, the only change is in the start offset. You will need to add horizontal size of front white bar to the luma and choma address.. 

There is no change in ROW_INCREMENT from first image to second image.

"Regarding Add horizontal size of front white bar",

If I want to move 360 pixels , how is offset calculated. If vid buffer format is in NV12 format? 

Add 360 to both luma and chroma address in this case.

You mean , DISPC_VID1_BA_j address right?

Yes, assuming you are able to display first image.. 

I just changed the address, I see, that the starting of the image is shifting, but the same image ending has degraded, and the clipped end portion of the image is displayed at the front also.

...
 

Again, is "original Image" displayed correctly? If this is working, then only proposed solution will work.

Yes, in previous post, the first screen is of orginal image displayed correctly. When we do the changes you mentioned, we got the second screen, where the original image did not shift as we expected.

ok, remove this offset addition. 

Can you help me understand

- what is output image size?

- what is input image size? 

In order to position input image to output image, please make sure to have output image size bigger than input image size.. 

Input Image size is 720*480
Output Image size is also, 720*480.
Pipeline  size is 1280*480

Output Image size we fixed with DISPC_VID1_FIR

I meant 

- what is the value in DISPC_VID1_SIZE

- what is the value in DISPC_VID1_PICTURE_SIZE

- and what is value in DISPC_SIZE_LCD. 

The frame size set in DISPC_SIZE_LCD register is used to send out the frame from the DSS. DISPC_VID1_PICTURE_SIZE is the size of the frame than DSS reads from the memory and DISPC_VID1_SIZE is the size of the frame that DSS puts on the overlay manager. 

If you want image1 or image2 as the output, your DISPC_SIZE_LCD should be bigger on horizontal side then DISPC_VID1_SIZE/DISPC_VID1_PICTURE_SIZE.  You can keep DISPC_VID1_SIZE and DISPC_VID1_PICTURE_SIZE to be same and then you can use DISPC_VID1_POSITION register to position input image onto bigger overlay. 

Regards,

Brijesh

Hi Brijesh,
Thank you for your inputs.

- what is the value in DISPC_VID1_SIZE ---->  1280*720

- what is the value in DISPC_VID1_PICTURE_SIZE ------> 720*480

- and what is value in DISPC_SIZE_TV -------> 1280 * 720


We tried changing  DISPC_VID1_POSITION but it is changing the entire pipeline position and below pipeline image is visible.

What we need is to keep the pipeline window as it is. But the image on the video pipeline to shift. The area without the image should be black.

Hi Ajith,

ok, that should be done in the application. The video pipeline cannot put black pixels on any side of the image.. Video pipeline can read the image, does pixel operations like scaling, color space conversion etc and then positions itself on the on the overlay image. 

But it cannot add black pixels before the image. If you require this, then please prepare this image in the memory and submit it to the DSS.

Regards,

Brijesh