Go to advanced search

by HermannSW
Sun Jun 16, 2019 10:45 pm
Forum: Camera board
Topic: Ultra high-speed imaging, capturing matrix style bullet time.
Replies: 4
Views: 544

Re: Ultra high-speed imaging, capturing matrix style bullet time.

I am not sure whether revalo still monitors this forum, you can find the wiring description in his github repo: https://github.com/revalo/pishot#gpio-based Yes, the work of revalo's team is amazing, capturing a single point in time with many Raspberry v1 cameras. You can do amazing stuff with a sing...
by HermannSW
Sat Jun 15, 2019 9:27 pm
Forum: Camera board
Topic: Convert MJPEG output to mp4
Replies: 4
Views: 131

Re: Convert MJPEG output to mp4

ffmpeg:
https://www.google.com/search?&q=conver ... mmand+line

P.S:
Off topic, I just used ffmpeg to cut out part of twitter video, and gifenc.sh to convert to animated .gif (robot's response is nice):
https://twitter.com/HermannSW/status/11 ... 0042497024
by HermannSW
Sat Jun 15, 2019 1:17 pm
Forum: Camera board
Topic: Raspberry v1 camera global (external) shutter videos
Replies: 23
Views: 2049

Re: Raspberry v1 camera global (external) shutter videos

I did a second look at 2nd global external shutter capture of pellet a 12kHz PWM frequency. I would have expected that the pellets (there are 4× more than in 1st capture with 3kHz PWM frequency) all are located on blue line because the pellet moved very fast (109.2m/s determined by 1st global extern...
by HermannSW
Sat Jun 15, 2019 1:41 am
Forum: Camera board
Topic: Raspberry v1 camera global (external) shutter videos
Replies: 23
Views: 2049

Re: Raspberry v1 camera global (external) shutter videos

My friend proposed to shoot through a stretched piece of paper and capture the pellet with v1 camera behind the paper. Of course that will reduce pellet speed, but since the pellet will create a hole that just allows the pellet to fly through, most of the oil cloud should remain behind the paper, a...
by HermannSW
Sat Jun 15, 2019 12:49 am
Forum: Camera board
Topic: Camera dropping frames, any advice?
Replies: 16
Views: 541

Re: Camera dropping frames, any advice?

I cannot see artifacts. I played with Linux "Videos" as well as with totem video player, both times more than 9s on the incrementing time display. Then I used vlc and indeed it completes faster, and does not show an incrementing seconds display. So yes, vlc does not play this video right, use anothe...
by HermannSW
Fri Jun 14, 2019 9:27 pm
Forum: Camera board
Topic: Camera dropping frames, any advice?
Replies: 16
Views: 541

Re: Camera dropping frames, any advice?

You don't say how you play the video. When I play it it shows nearly 10s length. And ptsanalyze shows 0 frameskips, and 291 frames at 30fps, that is 9.7s: $ ptsanalyze timestamp.pts 0 creating tstamps.csv 291 frames were captured at 30fps frame delta time[us] distribution 5 33324 11 33325 49 33326 1...
by HermannSW
Fri Jun 14, 2019 3:09 pm
Forum: Camera board
Topic: picamera minimize power consumption
Replies: 2
Views: 94

Re: picamera minimize power consumption

I doubt that you can increase battery lifetime much with that, since no Pi model has any sleep modes like ESPs or Arduinos. In "1W server challenge" thread I first measured an ESP32-CAM module to use 186mA at 3.3V only: https://www.raspberrypi.org/forums/viewtopic.php?t=238870#p1461306 I was totally...
by HermannSW
Fri Jun 14, 2019 9:10 am
Forum: Camera board
Topic: Scrolling Horizontal Blur
Replies: 7
Views: 195

Re: Scrolling Horizontal Blur

That's what I get for writing the post without checking. -fli, --flicker : Set flicker avoid mode (see Notes) ... Flicker avoid mode options: off,auto,50hz,60hz Please note that if your exposure time is below the flicker period then there is nothing you can do on the camera settings. Thank you for ...
by HermannSW
Fri Jun 14, 2019 7:24 am
Forum: Camera board
Topic: Scrolling Horizontal Blur
Replies: 7
Views: 195

Re: Scrolling Horizontal Blur

If it is more, then use the -fl option to specify the mains frequency, and ae will choose exposure times that are a multiple of the flicker period. I had seen mains flicker myself in the past and was not aware how to overcome that with a raspivid option (I bought led drivers that deliver DC to the ...
by HermannSW
Fri Jun 14, 2019 6:07 am
Forum: Camera board
Topic: Scrolling Horizontal Blur
Replies: 7
Views: 195

Re: Scrolling Horizontal Blur

EZKernel wrote:
Fri Jun 14, 2019 1:58 am
as it is not synced up to my capture speed.
What is your capture speed?
What mode?
raspivid or raspistill with combining frames afterwards?
(youtube video stats for nerds says the frames are 946x532 ?!?!?)
by HermannSW
Fri Jun 14, 2019 1:10 am
Forum: Camera board
Topic: Pi 3 B+, v2.1 camera abyssmal fps @1080p
Replies: 12
Views: 350

Re: Pi 3 B+, v2.1 camera abyssmal fps @1080p

@HermannSW what is the resolution of the monitor you are testing on? is it 1080p?. Wouldn't that be 12 frames skipped for your v2 result, being that 30fps and 10 seconds should equal 300 frames or is there some other way to calculate it like the camera actually didn't record for 10 seconds? No, as ...
by HermannSW
Thu Jun 13, 2019 7:38 pm
Forum: Camera board
Topic: High framerate raspivid (initially 640x480 at 180fps)
Replies: 24
Views: 6799

Re: High framerate raspivid (initially 640x480 at 180fps)

Until now "high framerate" did mean >100fps for me (with raspivid up to 200fps, with raspiraw up to 665/1007fps for v1/v2 camera). Recently I did use "global reset" mode of ov5647 v1 sensor with an external shutter to do high eps (exposures per second) captures of fastest for now airgun pellet with ...
by HermannSW
Thu Jun 13, 2019 6:16 pm
Forum: Camera board
Topic: Pi Microscope with inverted pi lens
Replies: 4
Views: 136

Re: Pi Microscope with inverted pi lens

So 10µm/px? Or 10µm/3280px? I got best result with a 20° lens, but I had to move it more than 10cm away from the imx219 sensor on the board. To avoid light effects, I finally used an aluminum tube in a microscope holder: https://www.raspberrypi.org/forums/viewtopic.php?t=210605&start=50#p1409956 htt...
by HermannSW
Thu Jun 13, 2019 5:36 pm
Forum: Camera board
Topic: Pi Microscope with inverted pi lens
Replies: 4
Views: 136

Re: Pi Microscope with inverted pi lens

Hi, I cannot answer the technical question. Like you I did remove the original v2 camera lens, but I added a M12 lens mount instead. That allowed to use all kinds of different M12 lenses: https://www.raspberrypi.org/forums/viewtopic.php?f=43&t=45887&p=1298451#p1279957 You say 10 micron (10µm) resolu...
by HermannSW
Wed Jun 12, 2019 10:38 pm
Forum: Camera board
Topic: Pi 3 B+, v2.1 camera abyssmal fps @1080p
Replies: 12
Views: 350

Re: Pi 3 B+, v2.1 camera abyssmal fps @1080p

Oops, that was for v1 camera, I just replaced with v2 camera, rebooted and get same 0 skips results with v2 camera and HDMI monitor connected: pi@raspberrypi3B:~ $ fork-raspiraw/tools/camver v2 camera found pi@raspberrypi3B:~ $ raspivid -md 1 -w 1920 -h 1080 -pts tst.pts -t 10000 -b 5000000 -fps 30 ...
by HermannSW
Wed Jun 12, 2019 10:32 pm
Forum: Camera board
Topic: Pi 3 B+, v2.1 camera abyssmal fps @1080p
Replies: 12
Views: 350

Re: Pi 3 B+, v2.1 camera abyssmal fps @1080p

I cannot recreate your findings, my Pi3B has connected HDMI monitor as well, and 0 frame skips! pi@raspberrypi3B:~ $ raspivid -md 1 -w 1920 -h 1080 -pts tst.pts -t 10000 -b 5000000 -fps 30 -o tst.h264 pi@raspberrypi3B:~ $ userland/tools/ptsanalyze tst.pts 0 creating tstamps.csv 294 frames were captu...
by HermannSW
Wed Jun 12, 2019 9:10 pm
Forum: Camera board
Topic: Pi 3 B+, v2.1 camera abyssmal fps @1080p
Replies: 12
Views: 350

Re: Pi 3 B+, v2.1 camera abyssmal fps @1080p

In addition to what 6by9 said, you can count the number of frames in tst.h264 by:
https://stackoverflow.com/questions/196 ... 6#19753646

Code: Select all

$ ffprobe -show_streams -count_frames -pretty tst.h264 2>/dev/null | grep nb_read_frames=
nb_read_frames=529
$
by HermannSW
Wed Jun 12, 2019 12:56 pm
Forum: Camera board
Topic: Pi 3 B+, v2.1 camera abyssmal fps @1080p
Replies: 12
Views: 350

Re: Pi 3 B+, v2.1 camera abyssmal fps @1080p

You did analysis of effective framerate alread, can you show the output of "ptsanalyze tst.pts 0" for more details?
https://github.com/Hermann-SW/userland/ ... ptsanalyze
by HermannSW
Tue Jun 11, 2019 9:16 pm
Forum: Camera board
Topic: raspiraw different output after raspberry update
Replies: 6
Views: 193

Re: raspiraw different output after raspberry update

Your command line is wrong, "-hd0" needs a filename. Since you now want the file that dcraw can decode, just remove "-hd0" and it will work. "-hd0" is needed to save the header to a separate file once and reduce the size of all frames by that size. Tool raw2ogg2anim copies the "-hd0" file together w...
by HermannSW
Tue Jun 11, 2019 9:07 pm
Forum: Camera board
Topic: Question on yuv I420 to grey conversion
Replies: 3
Views: 256

Re: Question on yuv I420 to grey conversion

Today I wanted to do grey extraction from raspividyuv video and not from ffmpeg generated .yuv as before. raspividyuv captures multiple of 16 vertical lines, for mode 1 (1920x1080) that is 1920x1088. This script extracts that grey image from last frame Y as .pgm binary file: $ cat yex #!/bin/bash ec...
by HermannSW
Mon Jun 10, 2019 11:53 pm
Forum: Camera board
Topic: Spy Camera Pixel size
Replies: 1
Views: 106

Re: Spy Camera Pixel size

Normally I would say, ask your vendor.
Adafruit has two spy cams of different module sizes, and Arducam has others.
But all seem to use ov5647 image sensor, and that has pixel size 1.4µm×1.4µm:
https://cdn.sparkfun.com/datasheets/Dev ... pdf#page=5
by HermannSW
Mon Jun 10, 2019 8:32 pm
Forum: Camera board
Topic: Changing the sensor to a better quality one
Replies: 2
Views: 162

Re: Changing the sensor to a better quality one

You can add M12 lens mount to v1(5MP) and v2(8MP) camera yourself:
viewtopic.php?f=43&t=45887&p=1279957#p1279957
by HermannSW
Mon Jun 10, 2019 8:12 pm
Forum: Camera board
Topic: Raspberry v1 camera global (external) shutter videos
Replies: 23
Views: 2049

Re: Raspberry v1 camera global (external) shutter videos

Quite some time ago I described somewhere to use two PIs, the first Pi0 using high framerate raspivid to detect bullet in frame, and that Pi0 signalling the 2nd Pi to trigger a single global external shutter shot. I thought about a visual trigger for capturing bullets again, this time with just one ...
by HermannSW
Mon Jun 10, 2019 7:29 am
Forum: Camera board
Topic: best compromise quality/size for time-lapse camera
Replies: 5
Views: 231

Re: best compromise quality/size for time-lapse camera

I just mentioned global external shutter and high framerate capturing in previous posting as general v1/v2 comparison features, not specific to your application scenario. Ok @HermannSW but I guess on a Pi Zero you can't get such high frame rate right? If you look eg. into 640x64 tool you see that it...
by HermannSW
Mon Jun 10, 2019 6:58 am
Forum: Camera board
Topic: best compromise quality/size for time-lapse camera
Replies: 5
Views: 231

Re: best compromise quality/size for time-lapse camera

I am sure there are scenes where 10 and 85 make a great difference, but if for your application there is none, go with 10. in some v2 looks better in other v2 looks worse, so the difference is not so clear, surely not so clear to be worth that price difference. From my main interests (global externa...

Go to advanced search