Hello, I have a Pico Mini B with SC3336 camera, and I have a serious problem that I dont know whats causing it and how to fix.
Some information: the board is located outside (sheltered), wired via cat6 (~10m) and using the other 2 pairs to inject 7.5v on the other end and step it down to 5v to power the board at the location.
Im using the simple_vi_bind_venc to output h264 to fifo with a python script that starts the encoder once a client opens the stream, the script just basicly forwards the stream to a client that displays it using jmuxer.
Nothing is running except rkaiq_3A_server (always) and the python script.
CPU usage while watching stream
rkaiq_3A_server ~8-14%
python script ~6-8%
simple_vi_bind_venc ~2-3%
Everything works fine at night (never flashing), but in daylight the stream sometimes flashes/strobes with black frames, at first I thought a issue with the script or jmuxer, but then I tested making a 3 second test.h264 with simple_vi_bind_venc to /tmp directly, moved to pc and played with bsplayer and its flashing, so something wrong with encoder or rkaiq_3A_server?
Cant attach the files here of the forwarded stream from script and direct output with just simple_vi_bind_venc
Heres recording of it: https://streamable.com/lx39ps
Pico Mini and SC3336 - stream flashing issue
Left is stream at night (no flashing), right is at day almost clear, with some clouds + sun (flashing with black frames)
Happens only with sun and some clouds that appear quite overexposed, doesnt seem to happen on overcast
Happens only with sun and some clouds that appear quite overexposed, doesnt seem to happen on overcast
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Based on the current available information, it is highly likely that the limitation lies in the 3A algorithm. The IQfiles configuration provided by Rockchip is mainly for indoor scenarios. In overexposed conditions, if the AE controls the exposure time too low, it may cause flickering.
We do not have the ability to recalibrate the IQfiles and cannot provide related technical support. However, you can try to limit the minimum exposure time to ensure that no flickering occurs. Modify the value of CISTimeSet->Linear->CISTimeRegMin in /etc/iqfiles/sc3336_CMK-OT2119-PC1_30IRC-F16.json to 100.
We do not have the ability to recalibrate the IQfiles and cannot provide related technical support. However, you can try to limit the minimum exposure time to ensure that no flickering occurs. Modify the value of CISTimeSet->Linear->CISTimeRegMin in /etc/iqfiles/sc3336_CMK-OT2119-PC1_30IRC-F16.json to 100.
Yes it definitely seems exposure and maybe some ISP buffer related, because i had also setup to take single jpg snapshots every 2 minutes for timelapse with simple_vi_bind_jpeg, and around the time of day when this would happen there would be some black images too with some coming thru good about ~700kb in size (jpg that is) so maybe there is not enough buffer when the scenery is very detailed with sun + some clouds etc.
Anyways I have tried with OverExpCtrl enabled in the IQ and it seemed in limited testing like that solved it at the cost of quite underexposed rest of image, I will try your suggestion and see how it goes, the pico mini is a great board and with the sc3336 it makes quite a good DIY combo just this small issue, shame that theres no calibration tool, the default shipped iq for sc3336 was already quite overexposed around lights indoor or outdoor, it would be completely blown out around lights, I have somewhat fixed that manually tweaking it..
Anyways I have tried with OverExpCtrl enabled in the IQ and it seemed in limited testing like that solved it at the cost of quite underexposed rest of image, I will try your suggestion and see how it goes, the pico mini is a great board and with the sc3336 it makes quite a good DIY combo just this small issue, shame that theres no calibration tool, the default shipped iq for sc3336 was already quite overexposed around lights indoor or outdoor, it would be completely blown out around lights, I have somewhat fixed that manually tweaking it..
Last edited by falcon on 2026-02-24 18:32, edited 3 times in total.
Unfortunately OverExpCtrl didnt fix it and CISTimeRegMin = 100 makes it crazy overexposed, I dont know what to do to solve this properly, was so happy about my project and now this issue completely screws it
I'm also interested in this topic for the same issue (even though with pico max board).
As far as I understood - by default the board fires up rkipc, but not rkaiq (which is supposed to do stuff configured for this camera with iq files). And now is the question - is there a way to configure default bootup rkipc process to use rkaiq (via media node?) or the only way is to use some of the examples instead of built in rkipc?
As far as I understood - by default the board fires up rkipc, but not rkaiq (which is supposed to do stuff configured for this camera with iq files). And now is the question - is there a way to configure default bootup rkipc process to use rkaiq (via media node?) or the only way is to use some of the examples instead of built in rkipc?
Hello,
Trying to dig a little bit deeper on the issue.
It looks like rkipc has controls (config options) for use rkaiq and camera config has overexposure control switched off. I've not yet tested all combinations (inconclusive yet) but it looks like rkipc does not use rkaiq. Or not at full extent. Or it does not change mode from night to day, which is setup for time of the day and, since device not always has proper time - it might not work as well.
The question is - is rv1106 version of rkipc uses rkaiq and corresponding camera json config files or those are just "leftovers" from another build?
Trying to dig a little bit deeper on the issue.
It looks like rkipc has controls (config options) for use rkaiq and camera config has overexposure control switched off. I've not yet tested all combinations (inconclusive yet) but it looks like rkipc does not use rkaiq. Or not at full extent. Or it does not change mode from night to day, which is setup for time of the day and, since device not always has proper time - it might not work as well.
The question is - is rv1106 version of rkipc uses rkaiq and corresponding camera json config files or those are just "leftovers" from another build?
I think the default rkipc also initiates the isp like rkaiq does, since I didnt want to use rkipc, i commented it out in RkLunch.sh and just run the isp by having running rkaiq_3A_server in background and I use the simple_vi_bind_venc output to fifo for video and simple_vi_bind_venc_jpeg for snapshotssstepane wrote: ↑2026-03-07 15:30 I'm also interested in this topic for the same issue (even though with pico max board).
As far as I understood - by default the board fires up rkipc, but not rkaiq (which is supposed to do stuff configured for this camera with iq files). And now is the question - is there a way to configure default bootup rkipc process to use rkaiq (via media node?) or the only way is to use some of the examples instead of built in rkipc?
I think I have found where to fix it.
It's needed to change rkipc.ini file (which is original rkipc-300w.ini on luckfox pico pro/max) and respectively camera json file, which is sc3336_CMK-OT2119-PC1_30IRC-F16.json in my case (for sc3336 module).
1. rkipc change is for
- make sure enable_aiq = 1
- init_form_ini = 0 (so it will use IQ json file settings instead)
2. changes to sc3336 json
- "BackLightCtrl": {
"Enable": 1,
- "OverExpCtrl": {
"Enable": 1,
Now it outputs not overexposed daylight scene.
Note, changes need to be done in files in /oem/usr/share & /oem/usr/share/iqfiles so on boot RkLunch.sh will copy then to their default locations.
It's needed to change rkipc.ini file (which is original rkipc-300w.ini on luckfox pico pro/max) and respectively camera json file, which is sc3336_CMK-OT2119-PC1_30IRC-F16.json in my case (for sc3336 module).
1. rkipc change is for
- make sure enable_aiq = 1
- init_form_ini = 0 (so it will use IQ json file settings instead)
2. changes to sc3336 json
- "BackLightCtrl": {
"Enable": 1,
- "OverExpCtrl": {
"Enable": 1,
Now it outputs not overexposed daylight scene.
Note, changes need to be done in files in /oem/usr/share & /oem/usr/share/iqfiles so on boot RkLunch.sh will copy then to their default locations.
Good you found a solution, my camera is exposed to direct sun/sky its a doorbell and the only thing that fixed the issues of the black frames seems to be
CISTimeSet -> Linear -> CISTimeRegMin 12, lowest i could get it to, when theres sun its a bit still overexposed but at least it seems to work, I also tried first OverExpCtrl and seemed to fix the issue but didnt, so depending what you use your cam for check if you get black frames on direct sun.
Also per the rockchip developer guide pdf for the isp apparently BackLightCtrl and OverExpCtrl cant be used at same time so only one may be actually active in your case.
"It is important to note that backlight compensation and strong light suppression cannot be
enabled at the same time"
Also I just make changes in /etc/iqfiles, it reflects changes on other locations
CISTimeSet -> Linear -> CISTimeRegMin 12, lowest i could get it to, when theres sun its a bit still overexposed but at least it seems to work, I also tried first OverExpCtrl and seemed to fix the issue but didnt, so depending what you use your cam for check if you get black frames on direct sun.
Also per the rockchip developer guide pdf for the isp apparently BackLightCtrl and OverExpCtrl cant be used at same time so only one may be actually active in your case.
"It is important to note that backlight compensation and strong light suppression cannot be
enabled at the same time"
Also I just make changes in /etc/iqfiles, it reflects changes on other locations
Last edited by falcon on 2026-03-12 10:26, edited 1 time in total.