Feb 22, 2018

Auto-starting mjpg-streamer on Octopi

The normal command for me to start my mjpg-streamer (from its directory) is:
    ./mjpg_streamer -i "./input_uvc.so -n" -o "./output_http.so -w ./www"

The problem arises, when you want this to start automatically when your Raspberry Pi reboots (or even run in the background). You can't just simply add an & and even the built-in -b(ackground) option doesn't seem to work amazingly well.

So, here's what I've been able to sort out:
Copy all of the files to:
    /usr/local/sbin/mjpg-streamer/mjpg-streamer-experimental
Test execution from any folder use the following full path:
    /usr/local/sbin/mjpg-streamer/mjpg-streamer-experimental/mjpg_streamer -i "input_uvc.so -n" -o "output_http.so -w ./www"

If you get the message "ERROR: could not find input plugin", use the following command:
    export LD_LIBRARY_PATH=/usr/local/sbin/mjpg-streamer/mjpg-streamer-experimental/

If you want it to run & stay running (background mode), use the -b switch:
    /usr/local/sbin/mjpg-streamer/mjpg-streamer-experimental/mjpg_streamer -i "input_uvc.so -n" -b -o "output_http.so -w ./www"

To stop the background mjpg-streamer daemon, use the following command:
    kill -9 `pidof mjpg_streamer`

To make the camera start-up automatically, add the following lines to /etc/rc.local:
    /usr/local/sbin/mjpg-streamer/mjpg-streamer-experimental/mjpg_streamer -i "input_uvc.so -n" -o "output_http.so -w ./www" export LD_LIBRARY_PATH=/usr/local/sbin/mjpg-streamer/mjpg-streamer-experimental/
Also, make sure that /etc/rc.local is set to execute:
    sudo chmod 755 /etc/rc.local

For clarity, the actual binary is mjpg_streamer but it is usually referred to in conversation as mjpg-streamer. If you're searching, search for both!

Flashing arduino mega2560 firmware from OctoPi

I have a clone Arduino Mega2560 that I keep having to make changes to the firmware for my 3D printer.  Most of the steps are straight forward:

  1. Make changes to firmware in Arduino software.
  2. Save as hex
  3. sftp/scp the file to the Raspberry Pi
The last step was the one that gave me so much grief.  For my particular setup, here's the command that works:
avrdude -p m2560 -c stk500v2 -P /dev/ttyUSB0 -D -U flash:w:Marlin.ino.mega.hex:i

Aug 24, 2012

Remove pictures from copy/paste into Excel

I don't know about the rest of you, but I constantly find myself copying & pasting information from websites into Excel spreadsheets so that I can manipulate the data, or to just keep track of it for future reference.

I recently did just this when creating backup copies of my different domain's DNS entries.  The problem is, when I paste the tabulated data into Excel, it includes hyperlinks & images.

Hyperlinks:  Luckily in the newer versions of Excel this is as easy as selecting the whole sheet, right-clicking and selecting "Remove Hyperlinks".

Images:  Images are a little more difficult, since they often times don't even exist inside a cell, so they can't be easily deleted.  Thanks to Dave Peterson over on the microsoft.public.excel newsgroup, I got this little nugget of information:

Hit Alt-F11 to get to the vbe (Visual Basic Editor)
Hit Ctrl-G  to see the "immediate" window
Type the following and then press enter:
Activesheet.pictures.delete
This blows them all away quickly & cleanly.  What's even better, is that if you're doing this multiple times, just keep copying & pasting pages in, then with each sheet highlighted, alt-tab back to the VBE screen, put your cursor at the end of the line & hit enter again to repeat the process.

Dec 14, 2011

Remove empty lines in text using Visual Studio

Visual Studio has ability to delete empty lines in replace operation using regular expressions.
  1. Click Ctrl-H (quick replace)
  2. Tick "Use Regular Expressions"
  3. In Find specify ^$\n
  4. In Replace box delete everything.
  5. Click "Replace All"
All empty lines will be deleted.

Jan 11, 2011

Google Checkout Issues with Android Market and Google Apps for Your Domain (GAFYD)

After upgrading GAFYD to the new infrastructure, I was no longer able to use the Android Market to purchase Apps for my DROID. After digging around for weeks for a solution to this, I was able to glean the following solution & decided to sum it up here.

Go to:
Google Apps Control Panel => Organization & Users
On the tabs below, click on the "Services" tab

Here's a direct link, if you substitute your domain name:
https://www.google.com/a/cpanel/{example.com}/Organization#Organization/subtab=1

Scroll down in the list to the "Other Google Services" section & make sure Checkout is "switched to on".

Mar 4, 2010

Take your ASP.Net 2.0 App Offline quickly!!!

I stumbled upon this little tidbit & decided it was reposting here. If you create a file in an ASP.Net 2.0 application named app_offline.htm it will bring down the appdomain & just return the contents of that HTML document!

Make sure your HTML page is at least 512bytes in size, or IE's "friendly errors" may eat it. :)

The MAJOR benefit I see here is that you can quickly rename a standby page to app_offline.htm, make a few changes (replace locked files, etc) & then rename it back to app_online.htm & you're back in business.

Jan 11, 2010

ASP Tags Not Recognized w/Nested Masterpages

Okay, I had an odd thing occur today while editing one of my projects. All of the tags had the red squiggly line under them, claiming:

“unrecognized tag prefix or device filter ‘asp’”

After a little searching I found a Google group post stating that:
”…building makes no difference. what does make a difference is leaving the nested master page file open in the IDE editor window…”

So, just keep your "nested" master page open & all will be well.