Hi Andrey,
We will fix the camera on a car. The light condition may change. AWB need to 
adapt to the change. For AE, the scene is normal in the office, there is not 
bright light. But it cannot converge to a stable status. We will attach images 
and videos of those problems later.

Tao Zhang
章   涛

发件人: Elphel Support [mailto:support-list@support.elphel.com]
发送时间: 2018年1月9日 4:02
收件人: Tao Zhang <tao.zh...@blacksesame.com.cn>; Elphel List 
<support-list@support.elphel.com>
抄送: Winston Zhang <winston.zh...@blacksesame.com.cn>; Elphel Sales | Olga 
Filippova <sa...@elphel.com>; Qun Gu <qun...@blacksesame.com>
主题: Re: [Elphel-support] 答复: 答复: 答复: 答复: 答复: 答复: Re: Quote for 1 NC393-Stereo 
camera

Tao,

I did not get the attached image to see your problem, but I expect you just 
need to modify the settings. Camera has a flexible control over AWB and AE to 
provide optimal operation for different lighting conditions. Most likely 
problem of of the instability is that there is a bright light source in the 
field of view.

First you need to make AE stable, then set or disable AWB (it only needs to be 
changed when you move from the indoors to outdoors), so if you work outdoors 
you may just set AWB once and then save parameters - that will make image 
matching easier.

For AE you may control:
1) the AE window (camera will only consider exposure for the selected 
rectangle, ignoring lights outside it.
2) The fraction of pixels that should have intensity values below certain 
threshold - reduce default value if there are lights in the FOV (especially 
electrical lights that have flicker)
3) The level (default 250) - target of autoexposure.
There are some illustrations on the wiki: 
https://wiki.elphel.com/wiki/Autoexposure

Andrey
---- On Mon, 08 Jan 2018 01:10:17 -0800 Tao 
Zhang<tao.zh...@blacksesame.com.cn<mailto:tao.zh...@blacksesame.com.cn>> wrote 
----
BTW, your stereo AE has oscillation and AWB is not accurate. Do you have 
updated firmware to solve these problems?

Tao Zhang
章   涛

发件人: Winston Zhang
发送时间: 2018年1月8日 16:54
收件人: Oleg 
<support-list@support.elphel.com<mailto:support-list@support.elphel.com>>
抄送: Elphel Sales | Olga Filippova <sa...@elphel.com<mailto:sa...@elphel.com>>; 
Dan Pan <ad...@blacksesame.com<mailto:ad...@blacksesame.com>>; Tao Zhang 
<tao.zh...@blacksesame.com.cn<mailto:tao.zh...@blacksesame.com.cn>>; Qun Gu 
<qun...@blacksesame.com<mailto:qun...@blacksesame.com>>
主题: 答复: [Elphel-support] 答复: 答复: 答复: 答复: 答复: Re: Quote for 1 NC393-Stereo camera

Hello
      Thank you for your patient to answer my question. But I have some others 
as follow.

1)    How should I make the left and right camera AWB change synchronously? The 
left camera image color is very different with right camera image color. Please 
look at the last email attachment. I followed your advices, and set the WB_EN=0 
and GAINR/GAING/GAINB = some value, and made the left and right camera image WB 
very close. But it just applies only to one situation. If I change the ambient 
lighting brightness, the GAINR/GAING/GAINB value should be set again.

2)    How should I make the left and right camera exposure change 
synchronously? The left and right camera exposure at different time and cause 
the image brightness different. So, if I capture the same timestamp frames, the 
frames brightness are so different. I want to do some stereo-match work, but 
all of these get me into trouble.



Best Regrad!
Yicheng-Zhang
Email:  
winston.zh...@blacksesame.com.cn<mailto:winston.zh...@blacksesame.com.cn>
Teil:    18516291005
Addr:   707 room, 7th floor, building 4th, No.1761, Zhangdong road, Pudong area

发件人: andersonnotg...@gmail.com<mailto:andersonnotg...@gmail.com> 
[mailto:andersonnotg...@gmail.com] 代表 Oleg
发送时间: 2017年12月28日 星期四 3:13
收件人: Winston Zhang 
<winston.zh...@blacksesame.com.cn<mailto:winston.zh...@blacksesame.com.cn>>
抄送: Elphel Sales | Olga Filippova <sa...@elphel.com<mailto:sa...@elphel.com>>; 
Dan Pan <ad...@blacksesame.com<mailto:ad...@blacksesame.com>>; Tao Zhang 
<tao.zh...@blacksesame.com.cn<mailto:tao.zh...@blacksesame.com.cn>>; Qun Gu 
<qun...@blacksesame.com<mailto:qun...@blacksesame.com>>; elphel support-list 
<support-list@support.elphel.com<mailto:support-list@support.elphel.com>>
主题: Re: [Elphel-support] 答复: 答复: 答复: 答复: 答复: Re: Quote for 1 NC393-Stereo camera

Hello,

1)    How could I get the raw data of camera. Because when I got the rgb data 
from multipart jpeg stream, the image had some color blocks if I amplified 
eight times. I thought it could be caused by image conversion 
compression.(please look at the attachments).

You can switch to JP4 format<https://wiki.elphel.com/wiki/JP4> - it's close to 
raw.
What I see in the attached images is they have different white balance. And 
also there are overexposed areas which can affect the correct balance.

The white balance is run independently for each sensor - you can try to set it 
so the images look the same and then turn off for both sensors:
a) open the web interface for each 
sensor<https://wiki.elphel.com/wiki/Tmp_manual#Web_user_interface_.28camvc.29> 
- click on the green circle OR
b) set WB_EN=0 (also for both channels) in 
parameters<https://wiki.elphel.com/wiki/Tmp_manual#Change_parameters> - if you 
change it through a table 
(http://192.168.0.9/parsedit.php?sensor_port=2&title=Parameters+for+groups:+whiteBalance+&GTAB_R&GTAB_G&GTAB_GB&GTAB_B&WB_THRESH&WB_PERIOD&WB_MASK&WB_EN&WB_WHITELEV&WB_WHITEFRAC&WB_MAXWHITE&WB_SCALE_R&WB_SCALE_GB&WB_SCALE_B&GAIN_MIN&GAIN_MAX&GAIN_CTRL&GAIN_STEP&ANA_GAIN_ENABLE)
 then there is a broadcast mask to set the parameter for all sensors at the 
same time - set it to F.

if I amplified eight times.
What are the gains and exposure for each sensor?

2)    The camera temperature has risen quickly, and I could not capture images. 
Because it was so slowly to run the video when the camera had been opened for 
four hours. But If I closed the camera and the temperature dropped down, the 
video was showed normally.

What is the temperature? http://192.168.0.9 > Temperature monitor
If it's around 70-80 it's ok (at 90 degrees the camera is forced to shut down)
Also, the camera should reach the steady temperature pretty much in the the 
first 30-60 mins.

- what is the image quality?
- what are the exposure times? you can try limiting exposure time. The default 
fps is 10 - so, It will get slow if exposure times are >100ms.
- is the camera and the pc the only devices in the network? camera connected 
directly to PC vie cable?
- connect to the camera via ssh and check cpu load:
$ ssh root@192.168.0.9<http://mailto:root@192.168.0.9>
root@elphel393:~# htop
then click on CPU% table header.
- your PC's cpu load? If you are watching from the browser - it might not be 
able to handle the streams as well.

Best regards,
Oleg Dzhimiev
Electronics Engineer
phone: +1 801 783 5555 x124
Elphel, Inc.
_______________________________________________
Support-list mailing list
Support-list@support.elphel.com<mailto:Support-list@support.elphel.com>
http://support.elphel.com/mailman/listinfo/support-list_support.elphel.com



_______________________________________________
Support-list mailing list
Support-list@support.elphel.com
http://support.elphel.com/mailman/listinfo/support-list_support.elphel.com

Reply via email to