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by Eichhorn18
Thu Nov 29, 2018 1:59 pm
Forum: Troubleshooting
Topic: rc.local , auto run .sh script at boot in Stretch Desktop
Replies: 6
Views: 454

Re: rc.local , auto run .sh script at boot in Stretch Desktop

The first and most obvious question is: What makes you think it is not working? I.e., what are the symptoms? The python script should capture photos and save them to the network mount. So the symptom is that the photos are not appearing on the network folder. The python script works fine otherwise ...
by Eichhorn18
Thu Nov 29, 2018 1:19 pm
Forum: Troubleshooting
Topic: rc.local , auto run .sh script at boot in Stretch Desktop
Replies: 6
Views: 454

Re: rc.local , auto run .sh script at boot in Stretch Desktop

If you want to stay with the rc.local method, then add am "&" to the end of the line, so that the script executes in the background. The other variant is to set up a systemd service (type simple), which is the preferred variant. Thanks for your reply. So I do have the & at the end of the line for r...
by Eichhorn18
Thu Nov 29, 2018 12:10 pm
Forum: Troubleshooting
Topic: rc.local , auto run .sh script at boot in Stretch Desktop
Replies: 6
Views: 454

rc.local , auto run .sh script at boot in Stretch Desktop

Hi, I am running Stretch Desktop on the Pi 3B. I am trying to run a .sh script at startup to do the following commands, including running a python script: #!/bin/bash sudo mount -a python3 /home/.../python_script.py The above mounts a network drive for which most of the commands to do that mount are...
by Eichhorn18
Tue Sep 11, 2018 1:29 pm
Forum: Camera board
Topic: picamera - capture causing GPU to be in race condition
Replies: 0
Views: 341

picamera - capture causing GPU to be in race condition

Hi, I seem to have put my raspberry pi into race conditions within the CPU or GPU. I am using picamera python library to capture photos. I've posted some other topics on this but not specific to this issue. I am capturing at resolutions 3264 x 2464 and have identified this issue with .JPEG, .YUV, an...
by Eichhorn18
Mon Sep 10, 2018 11:52 am
Forum: Camera board
Topic: YUV capture - is compression occuring?
Replies: 7
Views: 630

Re: YUV capture - is compression occuring?

Converting to RGB takes processing time and extra memory bandwidth. Whether you wish to do that on the Pi or offline is up to you. So the answer is yes, even though you said the sensor captures in 10bit/pixel bayer data, the next step is to process into YUV? Ah, the use case - always useful to know...
by Eichhorn18
Mon Sep 10, 2018 10:45 am
Forum: Camera board
Topic: YUV capture - is compression occuring?
Replies: 7
Views: 630

Re: YUV capture - is compression occuring?

Nothing captures 3 x 3264 x 2464. There is 1 x 3264 x 2464 coming from the sensor with pixels being coloured based on a Bayer colour filter. The ISP then interpolates to create the full colour image, but writes a YUV 4:2:0 image out. Conversion to RGB is based on that YUV4:2:0 image. Which format Y...
by Eichhorn18
Mon Sep 10, 2018 9:46 am
Forum: Camera board
Topic: YUV capture - is compression occuring?
Replies: 7
Views: 630

Re: YUV capture - is compression occuring?

That's fine. YUV has colour channels only downsampled colours from the bayer pattern(only 4x4 bayer pixels create one colour yuv pixel), while RGB interpolates these YUV colours to get a colour value for each pixel. Y -> 3264 x 2464 = 8042496 U -> 3264 x 2464 /4 = 2010624 V -> 3264 x 2464 /4 = 2010...
by Eichhorn18
Mon Sep 10, 2018 8:38 am
Forum: Camera board
Topic: YUV capture - is compression occuring?
Replies: 7
Views: 630

YUV capture - is compression occuring?

Hello, This question is about YUV capture using the camera v2.1. I have read that the sensor captures YUV natively, meaning it should be the raw data (neglecting bayer filtering). I understand the difference is format between YUV and RGB data. I have captured two images with the same resolution inpu...
by Eichhorn18
Fri Aug 31, 2018 3:05 pm
Forum: General discussion
Topic: RPi 3B+ gigabit ethernet bad download speeds.
Replies: 193
Views: 58764

Re: RPi 3B+ gigabit ethernet bad download speeds.

Well, from RAM you get 30 Mbyte/s. That is 240 Mbit/s which is approaching the expected max rate of ethernet on a RPi 3B+. It's true that is pretty decent. I wonder why the big difference (approximately 50%) for an internet connection that is supposed to give 800 Mbits/s on gigabit ethernet compute...
by Eichhorn18
Fri Aug 31, 2018 11:46 am
Forum: General discussion
Topic: RPi 3B+ gigabit ethernet bad download speeds.
Replies: 193
Views: 58764

Re: RPi 3B+ gigabit ethernet bad download speeds.

Copied from where on the 3B+? How fast can that place source data continuously? Copied from the SD card. I realize that in itself is an unfortunate bottleneck. I have also written files that are stored in RAM, directly to a network mounted folder on a windows machine using CIFS. The transfer speed ...
by Eichhorn18
Thu Aug 30, 2018 2:57 pm
Forum: General discussion
Topic: RPi 3B+ gigabit ethernet bad download speeds.
Replies: 193
Views: 58764

Re: RPi 3B+ gigabit ethernet bad download speeds.

So I'm trying to transfer files through my local network, and scp from my windows machine is showing a max transfer speed of 11.5 MB/s. What is required to check if flow control is turned on/off? I'm running an enterprise network through switches and some managed hubs. [email protected]:~ $ sudo ethto...
by Eichhorn18
Thu Aug 30, 2018 12:50 pm
Forum: Camera board
Topic: Camera preview works, but capture produces an all black .jpeg
Replies: 26
Views: 1760

Re: Camera preview works, but capture produces an all black .jpeg

A small update on this malfunction. I have identified that this problem can occur if the FFC camera cable is bent like a piece of paper, then unbent. I have identified some breakages in the cables that are not visible to the eye. Note to anyone trying to route these FFC cables, particularly if you a...
by Eichhorn18
Thu Aug 30, 2018 12:44 pm
Forum: Camera board
Topic: .PNG and .JPEG photo capture performance - GPU overclocking
Replies: 12
Views: 1291

Re: .PNG and .JPEG photo capture performance - GPU overclocking

...you may find it faster to do it on the ARM cores than asking the GPU to do it (250MHz processor vs 1.4GHz processor). That also allows the GPU to move on to capturing the next still for you. Can you please explain how this could be achieved? I'm not aware of a way to direct a process from python...
by Eichhorn18
Wed Aug 29, 2018 12:45 pm
Forum: Camera board
Topic: .PNG and .JPEG photo capture performance - GPU overclocking
Replies: 12
Views: 1291

Re: .PNG and .JPEG photo capture performance - GPU overclocking

Do you need colour? Or more specifically do you need RGB? 23MB per frame is giving you nearly zero compression as the raw RGB at 24MB. What I really need is a .bmp with colour but capturing directly to a bmp takes too long. I capture as RGB into an array and then post-process it offline of the rasp...
by Eichhorn18
Wed Aug 29, 2018 12:35 pm
Forum: General discussion
Topic: RPi 3B+ gigabit ethernet bad download speeds.
Replies: 193
Views: 58764

Re: RPi 3B+ gigabit ethernet bad download speeds.

CIFS is a dialect of the SMB protocol that Samba implements. We're fairly certain that has been resolved now anyway. It was stalling a single TCP connection rather than a speed issue. https://github.com/raspberrypi/linux/issues/2449 https://github.com/raspberrypi/linux/issues/2482 Yours sounds like...
by Eichhorn18
Wed Aug 29, 2018 9:06 am
Forum: General discussion
Topic: RPi 3B+ gigabit ethernet bad download speeds.
Replies: 193
Views: 58764

Re: RPi 3B+ gigabit ethernet bad download speeds.

There is a suspected issue with Samba (and perhaps other network sharing mechanisms) that we haven't got to the bottom of yet, that may be unrelated. The speedtest-cli result look exactly like flow control is not working effectively. Is there any known issues with cifs as an alternative to samba? J...
by Eichhorn18
Wed Aug 29, 2018 8:30 am
Forum: Networking and servers
Topic: How does mount.cifs transfer data from RAM
Replies: 3
Views: 434

Re: How does mount.cifs transfer data from RAM

ghans wrote:
Tue Aug 28, 2018 10:40 am
A good keyword for Google is "Linux VFS".

ghans
Thank you. This has illustrated my relatively recent adoption of linux. :roll:
by Eichhorn18
Wed Aug 29, 2018 8:28 am
Forum: Camera board
Topic: .PNG and .JPEG photo capture performance - GPU overclocking
Replies: 12
Views: 1291

Re: .PNG and .JPEG photo capture performance - GPU overclocking

Are you using a raspberry pi camera? It would be my guess that the camera is noisier than the distortion added by compressing to a 100% JPEG. If you capture images only for a limited period of time, you might consider buffering them to a ramdisk which writes much faster than an SD card. Yes I am us...
by Eichhorn18
Tue Aug 28, 2018 10:11 am
Forum: Networking and servers
Topic: How does mount.cifs transfer data from RAM
Replies: 3
Views: 434

How does mount.cifs transfer data from RAM

Hi there, This question relates to how linux works, but I have not had success finding the answer through search engines. I have a raspberry pi 3B that I have mounted a window network drive using mount.cifs. The mount point is a folder I created on the Desktop of the raspberry pi. My question relate...
by Eichhorn18
Mon Aug 27, 2018 12:26 pm
Forum: Camera board
Topic: .PNG and .JPEG photo capture performance - GPU overclocking
Replies: 12
Views: 1291

Re: .PNG and .JPEG photo capture performance - GPU overclocking

Two differences: 1) There is no hardware acceleration for PNG, whilst there is for JPEG. 2) PNG encodes an RGB image. JPEG encodes a YUV image. The camera always produces YUV, so therefore is a conversion from YUV to RGB required, and again this is done in software. Basically there is no easy way t...
by Eichhorn18
Tue Aug 21, 2018 3:55 pm
Forum: Camera board
Topic: .PNG and .JPEG photo capture performance - GPU overclocking
Replies: 12
Views: 1291

.PNG and .JPEG photo capture performance - GPU overclocking

Hi, I have been trying to capture high quality images from the picamera rapidly for a while now. I have been using the picamera python library. I recently did a comparison between some of the photo formats that can be taken. JPEG images with quality=100 (minimum compression), captures images at a ra...
by Eichhorn18
Wed Aug 15, 2018 10:15 pm
Forum: Networking and servers
Topic: scp transfer of .PNG photos---something doesn't work
Replies: 14
Views: 833

Re: scp transfer of .PNG photos---something doesn't work

I guess I am confused. In the python library picamera, the function capture.sequence() requires that the image format must be specified as an option "format='png' ". The first bit of code below did not work, but I've just rewritten it with your suggestion and (the second bit of code) now works and ...
by Eichhorn18
Wed Aug 15, 2018 4:14 pm
Forum: Networking and servers
Topic: scp transfer of .PNG photos---something doesn't work
Replies: 14
Views: 833

Re: scp transfer of .PNG photos---something doesn't work

The file type and the filename are different and unrelated. The simple fact is that you have no files in that folder that match the filename patterns *.PNG or *.png You need to spend a little while getting acquainted with file naming and handling in a Linux system... This experience should be the p...
by Eichhorn18
Wed Aug 15, 2018 3:31 pm
Forum: Networking and servers
Topic: scp transfer of .PNG photos---something doesn't work
Replies: 14
Views: 833

Re: scp transfer of .PNG photos---something doesn't work

no they are not, they seemed to be called samwise_image000? no png at all If you examine the file by right clicking in a desktop environment and looking at properties the file type is reporting as "PNG IMAGE". That is what the properties says of the photo when viewed on the Raspberry Pi. Interestin...
by Eichhorn18
Wed Aug 15, 2018 3:22 pm
Forum: Networking and servers
Topic: scp transfer of .PNG photos---something doesn't work
Replies: 14
Views: 833

Re: scp transfer of .PNG photos---something doesn't work

ls -al /home/pi/Desktop/folder/*.PNG ls: cannot access '/home/pi/Desktop/ge267/WORKING/*.PNG': No such file or directory ls -al /home/pi/Desktop/folder/ [email protected]:~/Desktop/ge267/WORKING $ ls -al /home/pi/Desktop/ge267/WORKING/ total 54708 drwxr-xr-x 3 pi pi 4096 Aug 15 15:10 . drwxr-xr-x 6 pi pi ...

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