2008-12-08 08:29:44     color mistach in BF548 over redhat desktop

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2008-12-08 08:29:44     color mistach in BF548 over redhat desktop

Maha lakshmi (INDIA)

Message: 66504   

 

Hi,

 

     I have observed color mismatch in the same file shown in device and the desktop. Please look at the file captured on the device as well as the screen shot of the original file in desktop. The kernel configured with the default display options (configured for SHARP LQ043 TFT LCD for BF548 EZKIT). The nano-X configured with MWPF_TRUECOLOR0888 and GrArea is used for displaying the image from buffer(tried all the options 0 to 8).

 

     In the desktop I have used ARGB8888 pixel format.

 

     Please tell me what should I do for bringing the device display as same as desktop one.

 

Thanks,

 

Maha

 

screen_deviceBF548EZKIT.png

Screenshot-desktop.png

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2008-12-09 09:57:36     Re: color mistach in BF548 over redhat desktop

Yi Li (CHINA)

Message: 66568   

 

Maha,

 

Please firstly verify the LCD driver and HW are OK, you may try running "video_test" or try to display simple colors like Red, Green, Blue.

 

Then you may try to display R/G/B in nanox, so that you could know what color format the nano-x is used.

 

-Yi

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2008-12-10 09:04:57     Re: color mistach in BF548 over redhat desktop

Maha lakshmi (INDIA)

Message: 66604   

 

Hi,

 

   According to the document http://docs.blackfin.uclinux.org/doku.php?id=sharp_lq043t1dg01#hardware_setup , the BF548 EZ kit supports frame buffer with RGB888 by default and the nano-X support the format MWPF_TRUECOLOR0888.

 

In the config file of nano-X configuration, it is given that

 

"The pixeltype of the native hardware or underlying graphics library.

This definition defines the PIXELVAL to be 32, 16 or 8 bits wide.

If using Linux framebuffer, set to MWPF_TRUECOLOR0888, and use fbset.

It also enables GdArea/GrArea for this particular pixel packing format."

 

 

Is it applicable to BF-548. I hope the BF548 frame buffer doesn't support ARGB pixel format.

 

 

 

Thanks,

 

Maha

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2008-12-10 09:13:46     Re: color mistach in BF548 over redhat desktop

Michael Hennerich (GERMANY)

Message: 66605   

 

What you are experiencing is a typical RGB888 versus BGR888 issue.

Both format exists and are used.

However the lq043 fb driver only supports RGB888 by default, it may be flipped by changing some defines in the driver.

Typically an application gets the supported color formats from the driver and then uses it accordingly.

In your case this does not happen. Please fix your application.

-Michael

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2008-12-13 07:01:45     Re: color mistach in BF548 over redhat desktop

Maha lakshmi (INDIA)

Message: 66691   

 

Hi Michael,

 

     You are absolutely right. I have changed my application with RGB888 pixel format and nano-X configured with MWPF_TRUECOLOR888. Now I'm getting exact color just like the desktop output.

 

Thanks,

 

Maha

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