2009-12-09 07:28:27     Resolution problem with ADV7183B

2009-12-09 07:28:27     Resolution problem with ADV7183B

Massimo Savina (ITALY)

Message: 83302   

Hi,

I'm developing an application based on BF548 and the decoder ADV7183B.

I'm working on EZ-KIT Lite (BF548) with plugged in the BLACKFIN A-V EZ-EXTENDER.

The uClinux version that I'm using is the 2009R1.

I made some changes to the driver bflackfin_cam to capture the video on PPI0 instead on PPI1 as originally.

Now I have two problems, one for colors and one for resolution.

With the command:

ffmpeg -f video4linux -r 10.0 -s 720x288 -i dev/video0 -qscale 5 -f mjpeg udp:192.168.1.201:1234

I capture video, but as you can see from the first immgine, using the 720x288 resolution I catch 4 times the same image

Instead using the command:

ffmpeg -f video4linux -s 360x270 -i /dev/video0 -f mpegts udp:192.168.1.201:1234

using a quarter of previous resolution does not capture the complete image (see image_360x270)

Furthermore, the colors are wrong compared to the original (see original.png)

any suggestions?

Thanks in advance

Massimo.

original.png

image_360x270.png

image_720x288.png

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2009-12-09 07:44:23     Re: Resolution problem with ADV7183B

Jean-Christian de Rivaz (SWITZERLAND)

Message: 83303   

The colors componants are inverted. The ADV7183 have a register to swap them.

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2009-12-09 11:04:36     Re: Resolution problem with ADV7183B

Massimo Savina (ITALY)

Message: 83304   

Tanks Jean-Christian,

Swapping colors (with register 0x27 in ADV7183B, 8th bit) the image changes but not correctly (see attached image).

Maybe is there another register to tweak?

tnx

Massimo

original.png

colors_swap.png

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2009-12-09 16:16:31     Re: Resolution problem with ADV7183B

Jean-Christian de Rivaz (SWITZERLAND)

Message: 83317   

The "colors_swap.png" look more correct to me: the green groups and the magenta regions are in there good places. But the blue is completely missing. A possible cause could be a shift in the color demodulation frequency.

Start by checking the exacte frequency used to run the chip. There is two documented frequency: 27MHz and around 28MHz. The chip registers need to be set for the used frequency. If I remember correctly, there is a define in the driver code to handle that.

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2009-12-10 08:12:28     Re: Resolution problem with ADV7183B

Massimo Savina (ITALY)

Message: 83355   

You remember well!. There is the define ADV7183B_28MHZ into the driver if you use an oscillator to 28MHz.

I tried to compile with ADV7183B_28MHZ but the result is the worst. (see image).

Also because I actually use an oscillator to 27MHz.

Thanks for the tip. I continue to look around them.

by.

Massimo

28MHz.png

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2009-12-10 09:10:55     Re: Resolution problem with ADV7183B

Jean-Christian de Rivaz (SWITZERLAND)

Message: 83359   

Strange. Are you certain to inject a fully valide PAL signal ?

If you use an other color modulation (e.g. NTSC or SECAM), you might need to chage some registres.

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2009-12-15 02:42:44     Re: Resolution problem with ADV7183B

Massimo Savina (ITALY)

Message: 83494   

I'm quite sure to put a PAL signal taken from a DVD player that plays a PAL DVD.

I tried with another player, but the result is identical.

Even with a camera the result is the same

Maybe I have to force the decoding of the signal in PAL mode, through the ADV7183B registers?

Tanks,

Massimo

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2009-12-15 03:55:09     Re: Resolution problem with ADV7183B

Jean-Christian de Rivaz (SWITZERLAND)

Message: 83523   

I have played with some boards that use this chip, but I never have see a such result.

At the time I have published the patch for the ADV7193 support, I haved tested it on the BF561 dev kit and in a custom board. Michael Hennerich have then extended the support to the BF533 dev kit. I don't know if anyone but you have tested this driver on a BLACKFIN A-V EZ-EXTENDER board. There is a possibility that something is specific to this board.

As it seem that the communication with the I2C bus and the PPI work as expected, I suppose that the problem might be in the immediate environement of the ADV7183B chip.

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2009-12-15 06:38:16     Re: Resolution problem with ADV7183B

Massimo Savina (ITALY)

Message: 83528   

Yes, the I2C and PPI work as expected, because I can change settings into ADV7183B chip. (for example, swap colors or change input channel), PPI also capture frames.

I compared the connection diagram of the AD7183B on BF561 eval and seems identical to that of 'Blackfin AV EZ-Extender board.

Rather than, changing the CPU and the clock frequencies at which he works (I'm working with BF548)

I'm getting some doubt because if I use the following command from Michael

ffmpeg -f video4linux -r 10.0 -s 720x288 -i dev/video0 -qscale 5 -f mjpeg udp:192.168.1.201:1234

I get the image four times (see picture attached)

Regards.

Massimo

vlcsnap-2009-12-15-12h00m59s61.png

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2009-12-15 13:45:16     Re: Resolution problem with ADV7183B

Jean-Christian de Rivaz (SWITZERLAND)

Message: 83536   

I have looked at the BLACKFIN A-V EZ-EXTENDER and I don't see how you can configure the jumper on it to send the ADV7183B LLC1 clock to the PPI1 clock. It sem that only the PPI0 clock can get it. Please check with an oscilloscope that the PPI1 clock is exactly like the ADV7183B clock.

Before changing the driver to use the PPI1, did you have tested that the PPI0 work correctly with the ADV7183B ?

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