Re[2]: bt878 AGC

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Thanks, Robert!

It seems it should work. ( not tested yet ).
Checking signal strength is not the right way, cause it is strength of TV
signal. If I am not right please correct me.

Regards,
Dmitry.

RD> I'm assuming you're using the stable bttv driver (v0.7.8) under 2.4.

RD> The Imagenation PXC200 seems to have ADC disabled by default. 
RD> Try:
RD>  insmod bttv card=29

RD> If that doesn't kill your card and if it works add the snipped of code
RD> from bttv-cards.c init_PXC200() to you cards init code (default?):

RD> btwrite(BT848_ADC_RESERVED|BT848_ADC__AGC_EN,BT848_ADC);

RD> The bttv driver has support for signal strength detection, which can be
RD> used to detect the presence of cameras. Maybe you could just disable the
RD> dead cameras?

RD> //assuming /dev/video device is opened
RD> struct video_tuner vt;
RD> ioctl(video_dev_fd,VIDIOCGTUNER,&vt);
RD> printf("Signal Strength = [%d]\n",vt.signal);


RD> Cheers,
RD> Robert.

RD> Dmitry Alexeyev wrote:
>> 
>> Hello.
>> 
>> I have BT878 card and external multiplexer with several monochrome cameras
>> connected to it. If one camera is off ( blank screen ), bt878
>> automaticaly increases brightness, so I can see nothing on frames from
>> other cameras.
>> How can i turn off AGC ?
>> 
>> Dmitry
>> 
>> _______________________________________________
>> Video4linux-list mailing list
>> Video4linux-list@xxxxxxxxxx
>> https://listman.redhat.com/mailman/listinfo/video4linux-list



RD> _______________________________________________
RD> Video4linux-list mailing list
RD> Video4linux-list@xxxxxxxxxx
RD> https://listman.redhat.com/mailman/listinfo/video4linux-list



-- 
С уважением,
 Dmitry                          mailto:D.Alexeyev@xxxxxxxxxx





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