Usbcamera not saving properly files

General
1

Hello,

I'm using node-red-contrib-usbcamera both in Buffer mode for streaming and in File mode to save pictures.

The issue I have is that in File mode, the files are saved only some times, while the output from the node is fine (payload, filename, filepath all OK), the files just don't exist.

Did you already face this issue and how did you solve it ?

Thanks !

Here is my flow:

[{"id":"b8a0d690.062448","type":"tab","label":"Camera","disabled":false,"info":"This flow include the driver for :\nOne USB webcam"},{"id":"6b7b72ce.8664fc","type":"usbcamera","z":"b8a0d690.062448","filemode":"0","filename":"image01.jpg","filedefpath":"1","filepath":"","fileformat":"jpeg","resolution":"5","name":"","x":550,"y":100,"wires":[["7265faa3.75b2a4"]]},{"id":"f37f9486.30bc68","type":"inject","z":"b8a0d690.062448","name":"","topic":"","payload":"","payloadType":"date","repeat":"5","crontab":"","once":true,"onceDelay":0.1,"x":130,"y":100,"wires":[["8e58a7fb.145c28"]]},{"id":"5e5eab8d.55a544","type":"base64","z":"b8a0d690.062448","name":"","action":"str","property":"payload","x":880,"y":100,"wires":[["99b24069.8ca18"]]},{"id":"99b24069.8ca18","type":"template","z":"b8a0d690.062448","name":"","field":"payload","fieldType":"msg","format":"handlebars","syntax":"mustache","template":"<img height=\"600px\" src=\"data:image/jpg;base64,{{{payload}}}\">","output":"str","x":1020,"y":100,"wires":[["6247e54b.f4930c"]]},{"id":"6247e54b.f4930c","type":"ui_template","z":"b8a0d690.062448","group":"6013b77f.8f01d8","name":"","order":4,"width":"0","height":"0","format":"<div ng-bind-html=\"msg.payload\"></div>","storeOutMessages":true,"fwdInMessages":true,"templateScope":"local","x":1160,"y":100,"wires":[[]]},{"id":"8a2c52df.ea0cc","type":"comment","z":"b8a0d690.062448","name":"Only one camera can be attached","info":"","x":200,"y":60,"wires":[]},{"id":"23c29700.5d3d9a","type":"ui_button","z":"b8a0d690.062448","name":"","group":"6013b77f.8f01d8","order":1,"width":0,"height":0,"passthru":false,"label":"Take picture","tooltip":"","color":"","bgcolor":"","icon":"fa-camera","payload":"","payloadType":"str","topic":"","x":130,"y":200,"wires":[["c42a6fb3.ae6b5"]]},{"id":"c42a6fb3.ae6b5","type":"function","z":"b8a0d690.062448","name":"set filename and mode","func":"msg.filename = \"image_\" + Date.now();\nmsg.filemode = 1;\nreturn msg;","outputs":1,"noerr":0,"x":330,"y":200,"wires":[["6b7b72ce.8664fc"]]},{"id":"8e58a7fb.145c28","type":"function","z":"b8a0d690.062448","name":"set filemode","func":"msg.filemode = 0;\nreturn msg;","outputs":1,"noerr":0,"x":290,"y":100,"wires":[["6b7b72ce.8664fc"]]},{"id":"7265faa3.75b2a4","type":"switch","z":"b8a0d690.062448","name":"","property":"filemode","propertyType":"msg","rules":[{"t":"eq","v":"0","vt":"str"},{"t":"eq","v":"1","vt":"str"}],"checkall":"true","repair":false,"outputs":2,"x":710,"y":100,"wires":[["5e5eab8d.55a544","cf8887a8.d676e8"],["522c5aa1.26d854"]]},{"id":"cf8887a8.d676e8","type":"debug","z":"b8a0d690.062448","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","x":870,"y":60,"wires":[]},{"id":"522c5aa1.26d854","type":"debug","z":"b8a0d690.062448","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","x":870,"y":180,"wires":[]},{"id":"6013b77f.8f01d8","type":"ui_group","z":"","name":"Camera","tab":"f50ca35c.d425b","order":1,"disp":true,"width":"20","collapse":false},{"id":"f50ca35c.d425b","type":"ui_tab","z":"","name":"Camera","icon":"fa-camera","order":2,"disabled":false,"hidden":false}]
2

What platform (Pi, macOS, Windows) are you running?
What version?

Where exactly are you trying to write the file to disk in your flow?

3

Hi,
I am working on Raspberry Pi with Rasbian Stretch.
I am writing the file on the default path /home/pi/Pictures.

It seems that if I send a command to take a picture while the camera is busy with the streaming part, the command is ignored. I'll try to manage this with a status node. If you have another idea I'll please to hear it.

Thanks

4

Where in the flow do you try to save the file?

5

Hi Charlotte,
So I assume you have (some kind of) a video stream already? Can't you just grab periodically individual pictures from that stream, instead of getting extra snapshot pictures from the camera? Or is the video stream perhaps not running through Node-RED?
Bart

6

You are right, it's much better ! A lot more faster !!
Thanks

1 Like
7

Hi Charlotte,
Nice to hear you managed to get it done!
If you have some time left, it would be nice if you could share a screenshot of (this particular part of) your flow, the flow json itself and some explanation. I'm pretty sure other users could benefit from your use case ...
Thanks in advance!!
Bart

1 Like
8

Yes sure.

I have a first line streaming the webcam and updating the image each 5 seconds, these images are automatically saved under /home/pi/Pictures/image01.jpg.
And a second line taking this picture and saving it under another name when the user is pressing the button on the dashboard.

Capture
Capture.PNG1328Ă—237 20.5 KB 

[{"id":"172a41fc.9701fe","type":"tab","label":"Flow 1","disabled":false,"info":""},{"id":"529141ec.8ee6c","type":"usbcamera","z":"172a41fc.9701fe","filemode":"0","filename":"image01.jpg","filedefpath":"1","filepath":"","fileformat":"jpeg","resolution":"5","name":"","x":330,"y":120,"wires":[["66e97202.20593c"]]},{"id":"34bba1ad.8e41be","type":"inject","z":"172a41fc.9701fe","name":"","topic":"","payload":"","payloadType":"date","repeat":"5","crontab":"","once":true,"onceDelay":0.1,"x":130,"y":120,"wires":[["529141ec.8ee6c"]]},{"id":"66e97202.20593c","type":"base64","z":"172a41fc.9701fe","name":"","action":"str","property":"payload","x":520,"y":120,"wires":[["2509ebee.5750a4"]]},{"id":"2509ebee.5750a4","type":"template","z":"172a41fc.9701fe","name":"","field":"payload","fieldType":"msg","format":"handlebars","syntax":"mustache","template":"<img height=\"600px\" src=\"data:image/jpg;base64,{{{payload}}}\">","output":"str","x":700,"y":120,"wires":[["ef26da2d.0024b8"]]},{"id":"ef26da2d.0024b8","type":"ui_template","z":"172a41fc.9701fe","group":"6013b77f.8f01d8","name":"","order":4,"width":"0","height":"0","format":"<div ng-bind-html=\"msg.payload\"></div>","storeOutMessages":true,"fwdInMessages":true,"templateScope":"local","x":880,"y":120,"wires":[[]]},{"id":"dd84c1a6.c4bc5","type":"ui_button","z":"172a41fc.9701fe","name":"","group":"6013b77f.8f01d8","order":1,"width":0,"height":0,"passthru":false,"label":"Take picture","tooltip":"","color":"","bgcolor":"","icon":"fa-camera","payload":"","payloadType":"str","topic":"","x":130,"y":180,"wires":[["c64474d1.d018e8"]]},{"id":"c64474d1.d018e8","type":"file in","z":"172a41fc.9701fe","name":"","filename":"/home/pi/Pictures/image01.jpg","format":"","chunk":false,"sendError":false,"encoding":"none","x":390,"y":180,"wires":[["5dae658c.dce01c"]]},{"id":"5df71bd2.13faf4","type":"file","z":"172a41fc.9701fe","name":"","filename":"","appendNewline":true,"createDir":false,"overwriteFile":"true","encoding":"none","x":830,"y":180,"wires":[[]]},{"id":"5dae658c.dce01c","type":"function","z":"172a41fc.9701fe","name":"set filename","func":"date = Date.now();\nday = date.prototype.getDate();\nmonth = date.prototype.getMonth();\nyear = date.prototype.getFullYear();\nhours = date.prototype.getHours();\nmin = date.prototype.getMinutes();\nsec = date.prototype.getSeconds();\n\nformated_date = year + month + day + \"_\" + hours + min + sec;\n\nmsg.filename = \"/home/pi/Pictures/image_\" + formated_date;\nreturn msg;","outputs":1,"noerr":0,"x":650,"y":180,"wires":[["5df71bd2.13faf4"]]},{"id":"6013b77f.8f01d8","type":"ui_group","z":"","name":"Camera","tab":"f50ca35c.d425b","order":1,"disp":true,"width":"20","collapse":false},{"id":"f50ca35c.d425b","type":"ui_tab","z":"","name":"Camera","icon":"fa-camera","order":2,"disabled":false,"hidden":false}]
2 Likes
9

Just be careful, saving that frequently to a sd card will not be good in the long run, better use a usb memory stick and mount that to a new folder. Or even better, use a local ssd disk or a shared one (via samba)

10

Ok thanks.
It won't be good because of the volume of the pictures ?

11

Once thing is the total volume, nbr of pictures, depending on the size of your sd card, the other critical is number of times you write data to the card, it can wear out

Myself, I also have a house keeping python script, erasing pictures older than a number of days to free up space. The script is executed daily by Node-RED and it erases pictures older than 14 days

image
image.png936Ă—139 11.7 KB

The content of the python script:

import os
import time

workdir = "/media/pi/USB P/MotionPics"
 
now = time.time()
old = now - 14 * 24 * 60 * 60

for f in os.listdir(workdir):
    path = os.path.join(workdir, f)
    if os.path.isfile(path):
        stat = os.stat(path)
        #print stat
        if stat.st_ctime < old:
            #print "removing: ", path
            os.remove(path) # uncomment when you will sure :)
1 Like