[libcamera-devel] How to activate AGC control in libcamera, or set the GAIN/EXPOSURE parameter by v4l2 command.

[tetsuya.nomura at soho-enterprise.com]

Dear Laurent-san

Thank you for your advice.

I've tried the "Save As" button, specify the file name, and saved, but I cannot find it there.
On the other hand, I could store the raw data starting with " qcam -s role=viewfinder -s role=stillraw".

Best Regards,

NOMURA

-----Original Message-----
From: Laurent Pinchart <laurent.pinchart at ideasonboard.com> 
Sent: Tuesday, September 29, 2020 8:31 AM
To: tetsuya.nomura at soho-enterprise.com
Cc: 'David Plowman' <david.plowman at raspberrypi.com>; 'Kieran Bingham' <kieran.bingham at ideasonboard.com>; libcamera-devel at lists.libcamera.org
Subject: Re: [libcamera-devel] How to activate AGC control in libcamera, or set the GAIN/EXPOSURE parameter by v4l2 command.

Hello Nomura-san,

On Tue, Sep 29, 2020 at 08:24:33AM +0900, tetsuya.nomura at soho-enterprise.com wrote:
> Dear David-san
> 
> Thank you for your comments.
> As you mentioned, I also think AEC and AGC is the inseparable 
> functions, and if AGC is active in dark condition I see the noise is amplified to reach to AGC target.
> However, I don't see the noise increasing, so I estimated the AGC is not working.
> 
> I'll do the experiment with original Raspi camera and report to you.
> 
> And I'll try to capture the JPEG image.
> (I wonder qcam does not support jpeg capture at this moment, right?)

qcam supports JPEG capture when pressing the "Save As" button (or pressing the Ctrl-Shift-S shortcut), and DNG capture when pressing the "Save Raw" button. To enable DNG capture, the -s option must be specified on the command line:

qcam -s role=viewfinder -s role=stillraw

Please note that stillraw will be renamed to raw in the near future, qcam will then output a message to complain that stillraw isn't known:

Unknown stream role stillraw

--
Regards,

Laurent Pinchart