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by Kozuch
Wed Aug 01, 2018 3:28 pm
Forum: Camera board
Topic: Hardware camera sync pulses
Replies: 27
Views: 2661

Re: Hardware camera sync pulses

Sync of single photo should be possible (long term video is not, both cameras will drift, because they each have separate oscilator). See here for more info: https://www.raspberrypi.org/blog/frozen-pi-bullet-time-photography-with-the-raspberry-pi/ You will have a setup similar to the one liked, but ...
by Kozuch
Fri Jul 20, 2018 10:10 am
Forum: Camera board
Topic: IMX219 rolling shutter effect severity
Replies: 18
Views: 2644

Re: IMX219 rolling shutter effect severity

There is a nice relevant post about measuring rolling shutter effect.
by Kozuch
Thu Jun 28, 2018 2:45 pm
Forum: Camera board
Topic: Raw sensor access / CSI-2 receiver peripheral
Replies: 503
Views: 99430

Re: Raw sensor access / CSI-2 receiver peripheral

Is it possible to control line blanking on the sensor somehow? I mean adding/removing a blanking interval line. The feature would come in handy for frame synchronization as it may allow to bring multiple cameras to sync.
by Kozuch
Thu Jun 28, 2018 2:31 pm
Forum: Camera board
Topic: Frame synchronisation
Replies: 82
Views: 27676

Re: Frame synchronisation

Looks like this topic has been idle for some time. However since last summer it is possible to get HW camera sync pulses to a GPIO so one can precisely measure the level of sync. It has been said in another thread that on a stereo camera it may be possible to achieve a "nearest line level" sync of t...
by Kozuch
Mon May 21, 2018 8:01 pm
Forum: Camera board
Topic: Hardware camera sync pulses
Replies: 27
Views: 2661

Re: Hardware camera sync pulses

Line 1226 is [email protected]_0_LED. Amend that section appropriately. Could someone please provide me with a sample part of https://github.com/raspberrypi/firmware/blob/master/extra/dt-blob.dts for Pi 3 v1.2 (pins_3b2) if I want to map the camera led to GPIO21 (pin #40) to get the sync pulses the...
by Kozuch
Wed Apr 25, 2018 11:05 pm
Forum: Camera board
Topic: Hardware camera sync pulses
Replies: 27
Views: 2661

Re: Hardware camera sync pulses

Do the sync pulses respect the framerate setting done by --framerate/-fps parameters of RaspiVidYUV? If I request a framerate of 5 Hz, does the sensor run at 5 Hz (and hence give 5 Hz sync pulses) or is the framerate lowered in software with the sensor running at a higher framerate?
by Kozuch
Wed Apr 25, 2018 9:05 pm
Forum: Camera board
Topic: Grayscale Video
Replies: 4
Views: 817

Re: Grayscale Video

Is it somehow possible to save grayscale video only and not color to save space? I am interested in uncompressed video.

Edit: I see there is the option "-luma" in Raspividyuv - looks like this only saves mono to file.
by Kozuch
Thu Apr 19, 2018 2:36 pm
Forum: Camera board
Topic: Hardware camera sync pulses
Replies: 27
Views: 2661

Re: Hardware camera sync pulses

Nice to hear we've got a precise frame signal from the camera! You do not mention any camera modes so I guess this will work in ANY camera mode (video, stills), am I right? I also guess this may be working regardless of other camera settings (shutter speed, ISO etc.). Would you confirm please?
by Kozuch
Fri Apr 13, 2018 1:40 pm
Forum: Advanced users
Topic: Syncing a high power LED array to camera start frame.
Replies: 32
Views: 1105

Re: Syncing a high power LED array to camera start frame.

Do I understand this correctly that with some sort of setting ("disable_camera_led=3") and a setup described above one can get a GPIO signal when a frame exposure starts? Does this work only with still capture more or also in video (sensor running freely) mode (still/video MMAL ports)?
by Kozuch
Thu Apr 12, 2018 4:19 pm
Forum: Compute Module
Topic: Stereo camera frame synchronization
Replies: 18
Views: 5740

Re: Stereo camera frame synchronization

Will I be able to measure the drift by having two RPis with one camera board each to output a GPIO signal when frame is received in the Raspicam C++ API (uco.es) and measure the drift between two GPIO inputs on th 3rd RPi? All implemented in C++.
by Kozuch
Thu Apr 12, 2018 3:32 pm
Forum: Compute Module
Topic: Stereo camera frame synchronization
Replies: 18
Views: 5740

Re: Stereo camera frame synchronization

Bump - could anyone tell what the drift will approximately be after 1 hour (if they were started in perfect sync)?
by Kozuch
Sun Mar 19, 2017 2:13 am
Forum: Troubleshooting
Topic: Compile PWC Module
Replies: 7
Views: 2362

Re: Compile PWC Module

Has anyone made any progress? I am trying Logitech Quickcam Pro 4000 on RPi 3 with all sw current (firmware, raspbian, linux kernel 4.9). lsusb lists the device correctly, but fswebcam returns a black frame (the cams led flashes briefly though). qv4l2 returns black frame for pwc mode too, and comple...
by Kozuch
Sun Mar 19, 2017 2:08 am
Forum: Troubleshooting
Topic: pwc driver
Replies: 32
Views: 8989

Re: pwc driver

Does anyone know if this got any better? Trying Logitech Quickcam Pro 4000 on RPi 3 with all sw current (firmware, raspbian, linux kernel 4.9). lsusb lists the device correctly, but fswebcam returns a black frame (the cams led flashes briefly though). qv4l2 returns black frame for pwc mode too, and ...
by Kozuch
Sat Mar 18, 2017 11:33 am
Forum: Camera board
Topic: IMX219 rolling shutter effect severity
Replies: 18
Views: 2644

Re: IMX219 rolling shutter effect severity

Well these nanosecond values are each meant to be line readout time for a given camera mode (and thus given camera resolution) right? For me this implies that if line readout time is about the same for mode 2 (5 Mpix) and mode 6 (VGA) then in mode 2 the rolling shutter effect should be 4x worse than...
by Kozuch
Tue Mar 14, 2017 11:49 am
Forum: Camera board
Topic: IMX219 rolling shutter effect severity
Replies: 18
Views: 2644

Re: IMX219 rolling shutter effect severity

The video you posted is great :). Long live jello! Ok, so you confirm that binning HAS effect on rolling shutter severity, right? Is the readout when binning really processed faster? Sorry to be this annoying but maybe can we reference the readout duration from the datasheet (of either v1 or v2 sens...
by Kozuch
Mon Mar 13, 2017 11:54 pm
Forum: Camera board
Topic: IMX219 datasheet and driver
Replies: 0
Views: 3576

IMX219 datasheet and driver

Dont know if you noticed but there is datasheet and some code that looks like a driver here:

https://github.com/rellimmot/Sony-IMX21 ... Pi-V2-CMOS
by Kozuch
Mon Mar 13, 2017 11:18 pm
Forum: Camera board
Topic: IMX219 rolling shutter effect severity
Replies: 18
Views: 2644

Re: IMX219 rolling shutter effect severity

Even pixel binning (like 2x2 or even 4x4 on the v1 camera) wont speed up the readout? (and thus mitigate the rolling shutter?)
by Kozuch
Sat Mar 11, 2017 4:44 pm
Forum: Camera board
Topic: IMX219 rolling shutter effect severity
Replies: 18
Views: 2644

IMX219 rolling shutter effect severity

Hi there, I am interested to see how severe is the rolling shutter effect on the v2 camera board (with IMX219) when compared to the original v1 camera. I know may be highly subjective to evaluate the effect because it depends heavily on usage case. However, for my usage case the effect is it very ne...
by Kozuch
Tue Feb 28, 2017 1:08 am
Forum: Compute Module
Topic: Stereo camera frame synchronization
Replies: 18
Views: 5740

Re: Stereo camera frame synchronization

As stressed before, the sensors are running off independent oscillators so they will drift once started. You're probably OK for a few minutes, but don't try hours. Can you guess what will the drift be after 1 hour (if they were started in perfect sync)? I mean a rough guess given the grade of oscil...
by Kozuch
Sat Feb 25, 2017 9:21 pm
Forum: Camera board
Topic: Camera flash driver released
Replies: 38
Views: 8692

Re: Camera flash driver released

Is the flash driver working with the new v2 camera board?
by Kozuch
Sun Feb 19, 2017 11:21 am
Forum: Camera board
Topic: [Help] Shading Correction, Camera v2 after Lens Removed
Replies: 13
Views: 3506

Re: [Help] Shading Correction, Camera v2 after Lens Removed

Hi 6by9, Er, how does physics know that the lens is in front of the camera is a v1 or v2? That would be magic, and I want a similar option to turn gravity on and off :roll: Read the Pixel vignetting section of https://en.wikipedia.org/wiki/Vignetting. That is what is being compensated for. well I me...
by Kozuch
Sun Feb 19, 2017 12:10 am
Forum: Camera board
Topic: [Help] Shading Correction, Camera v2 after Lens Removed
Replies: 13
Views: 3506

Re: [Help] Shading Correction, Camera v2 after Lens Removed

Any news on this topic? If the lens shading can not be disabled then as Rado says third party lenses may easily be out of game... The only way seems to be using the raw Bayer output as suggested here - can someone confirm it will turn the shading off? Also, if I understand correctly, shading is only...
by Kozuch
Sat Feb 18, 2017 6:14 pm
Forum: Camera board
Topic: Camera flash driver released
Replies: 38
Views: 8692

Re: Camera flash driver released

Thanks for reply again! I see you would probably dont like to see the driver "being abused" for other things :) but from what I read I get the expression that it may be usable for me actually... because if I do not use flash there will be no difference on 1st and 2nd frame (preflash) and the AE shou...
by Kozuch
Thu Feb 16, 2017 3:23 pm
Forum: Camera board
Topic: Camera flash driver released
Replies: 38
Views: 8692

Re: Camera flash driver released

6by9, thanks for your fast reply! I will be using a setup based on this hardware - RTK GPS is used and the flash sync signal is captured as a timestamp on GPS device and later interpolated for precise location. I basically want to replace the Sony NEX camera from that article with RPi camera. I dont...
by Kozuch
Thu Feb 16, 2017 12:58 pm
Forum: Camera board
Topic: Camera flash driver released
Replies: 38
Views: 8692

Re: Camera flash driver released

I would like to use hardware flash sync signal for precise photo geotagging. If I understand this thread correctly, the flash driver is among other things able to send electric pulse to a given GPIO pin - is this correct? Since this is operated by the firmware I think the delay between frame exposur...

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