Tips, scripts and tricks from a seasoned website manager

Troubleshooting DLIBDOTNET and FaceRecognitionDotNet CUDA libraries

I’ve been building a Facial Recognition C# application leveraging the DLIBDOTNET and FaceRecognitionDotNet libraries. I tested a variety of free libraries and this is the most accurate at reliably predicating/recognizing faces. It also does a decent job of differentiating people of color.

There are two libraries, the regular “FaceRecognitionDotNet” library and the CUDA versions. Although it isn’t necessary to have CUDA to use this library, the recognition will be much faster if you leverage the CUDA version.

It’s been a process to get the CUDA version of these two libraries to work but it’s been worth it. Here’s a guide that could help you troubleshoot if you are having difficulties getting this to work.

What you’ll need & Steps

Although not necessary, the setup may work more smoothly if you follow these steps in this order.

64 bit Intel CPU. Visit the GitHub repository for current supported CPUs.
Nvidia CUDA supported GPU
Visual Studios 2019 & NET CORE 2.0+. I initially wrote my application using the old school Visual Studios Forms. After banging my head against the wall, I did some research and found out that WPF type applications have more native support for GPU applications. After switching to .NET Core 2.0 and a WPF application, I finally got the CUDA version of this library to work.
Nvidia CUDA development kit. The CUDA Nvidia development kit will detect your graphics card and will most likely install an older graphics card driver. Let it install the older version otherwise you will get an error message during the install. After the install completes, reinstall the most current Nvidia drivers for your graphics card. It’s also important to install Visual Studios before the CUDA development kit because the installation package will attempt to install integration tools for Visual Studios. After installation is complete, make sure CUDA was installed properly by running one or more of the sample projects. You shouldn’t receive error messages after building and running the sample project. This is how you know it was installed properly.
NVIDIA cuDNN – Follow the instructions on NVIDIA’s website to install cuDNN. You are simply just copying files into the CUDA installation directory. Yes, there isn’t anymore to the cuDNN installation. I used version 10.0. I also tested with newer version of CUDA however these tests were unsuccessful so I decided to stick with 10.0. Remember, you need to install the CUDA development kit before attempting to install cuDNN.
You will also need at least 25 Gigs free space on the drive that has Windows. Visual Studios, CUDA and NVIDIA graphic drivers are bulky.

This is using a barebones Visual Studios installation. The DLIBDOTNET notes on NuGet mention that you need these files. Visual C++ 2017 Redistributable Package, cublas64_92.dll, cudnn64_7.dll, curand64_92.dll and cusolver64_92.dll. I attempted to simply just install the latest Visual C++ 2019 Redistributable and that itself didn’t work so I installed a few other C++ and .NET CORE components. See below for my barebones install of Visual Studios.

Individual Components

.NET

.NET Core 2.1 LTS Runtime
.NET Core 3.1 LTS Runtime
.NET Core SDK
NuGet package manager
.NET Framework 4.6.1 targeting pack
.NET Framework 4.7.2 SDK
.NET Framework 4.7.2 targeting pack
.NET Framework 4.8 SDK
.NET Native
.NET Portable Library targeting pack
Development Tools plus .NET Core 2.1

Cloud, database, and server

CLR data types for SQL Server

Code tools

C# and Visual Basic Roslyn compliers
C++ 2019 Redistributable MSMs
C++ 2019 Redistributable Update
C++ Cmake tools for Windows
MSBuild
MSVC v142 – VS 2019 C++ x64/x86 build tools (v14.25)

Debugging and testing

.NET profiling tools
C++ AddressSanitizer (Experimental)
C++ profiling tools
Just-in-Time debugger

Development activities

C# and Visual Basic
C++ core features
F# language support
IntelliCode

Games and Graphics

Graphics debugger and GPU profiler for DirectX

SDK, libraries and frameworks

C++ ATL for latest v142 build tools (x86 & x64)
Windows 10 SDK(10.0.18362.0)

After you are done with the above steps, create a simple Windows WPF .NET CORE application and run call the “TryGetDriverVersion” function. Sample code below. If everything was installed properly, you should see an output like this

“***HELLO CUDA Version:10010”

using DlibDotNet;

//C# example code to check if DLIB Cuda is installed properly. Make sure you are using the CUDA version from NuGet

 Cuda.TryGetDriverVersion(out int version);
         Debug.WriteLine("***************************************HELLO CUDA Version:" + version.ToString()) ;

I’ve been able to get this to work with a few different CUDA supported GPUs following the instructions above. Enjoying coding.

Automatically highlight selected Excel row

Here’s a simple script that makes it easier to visually scan lengthy Excel spreadsheets. If you spend a lot of time in Excel spreadsheets, you’ll find this useful.

What you’ll need

.XLSM Excel workbook
Macros enabled

Excel spreadsheet with color highlighting — Excel VBA script that automatically highlights current selected row

Excel VBA script that automatically highlights current selected row

Although I like this above script, you do have to hard code a few values. Here’s another Exel video that is more straight forward. This method also highlights the columns. This video, assumes you already know how to enable the developer tab and create formulas however.

'Visual Basic for applications code
Private Sub Worksheet_SelectionChange(ByVal Target As Range)

    With ThisWorkbook.Names("CurrentRow")
    .Name = "CurrentRow"
    .RefersToR1C1 = "=" &amp; ActiveCell.Row
'above "&amp;" should be the ampersand symbol. 
    End With

End Sub

How to check a website for chain redirects/circular redirects

I recently migrated one of my sites to HTTPS. Although this seems like a simple change, the site went down because circular redirects were accidentally created.

screenshot of page not working due to circular redirect — Screenshot of site down due to too many redirects.

There are a couple of tools you can use to identify chain/circular redirects. Not only will misbehaved redirects bring down your site, they can slow it down, and also adversely impact your search engine rankings. So, here are a couple of ways to identify these types of redirects.

Using a command prompt. (this is more slick approach that will earn you some street cred with your IT folks) Type. “curl -L -i https://www.angelskills.com/wp”. Make sure you replace my blog with your own website:). If your redirects were setup correctly, you should only get HTML source code of the page.

Screenshot of Windows Command prompt showing the Curl command and 50 redirects

Now, if it’s not setup correctly, you will see a long list of redirects(reference screenshot above). In my case there were 50. This was not good. For a summarized review of this result remove the “-i” so this “curl -L https://www.angelskills.com/wp”. Now we have since resolved my circular redirect issue so I recreated an example for you to try out with curl. Use this link. “http://www.angelskills.com/test/a.html “. Most browsers are smart enough to know that this will cause an infinite loop but you can still see the magic by using curl or the Chrome extension below.

Screenshot of Windows Command prompt showing the Curl command. This was when I had a circular redirect in place.

The other approach which isn’t as grandiose is to use a boring Chrome extension. “Redirect Path” works nicely.

Screenshot of Redirect Path Chrome Extension tool

How to mute your computer microphone with a single keyboard key

With everyone working remote these days, it is nice to follow phone/video conference etiquette and mute your microphone if you are not the speaker. I was surprised to learn that there isn’t a dedicated mute key on most keyboards to mute your microphone. The mute button on my laptop and keyboard only mute the speakers. So here’s a script I put together that mutes your microphone. It relies on registry values so it is more dependable than hacking your system by emulating send keys values. This works best with keyboards or mice with customization capabilities. I’m using a Logitech keyboard. Alternatively, you can also use keyboard shortcuts.

What you’ll need before starting.
* Administrative or elevated privileges to your computer
* A little determination

Step 1: Identify your microphone registry values. Yes, this isn’t for the faint of heart.
Step 2: Modify Powershell script below. Replace “Placeholder” with your register value. Save file as “mute.ps1”.
Step 3. Create a simple .bat script that calls the PowerShell script with the proper execution permissions. (note, you may also need to run this code in an administrative PowerShell window. “set-executionpolicy unrestricted” if the code is still not executing. Call the file “mute.bat”.
Step 4: Update Folder ownership within Regedit for the folder containing the “microphone array” item. Change it from “System” to all users and applications.
Step 5: Customize keyboard key to reference this “mute.bat” script when the button is pressed.

Note, I implemented this on Windows 10 Pro. Version 1903. The script does modify a single Registry value so you may want get buy-in from your IT department prior to incorporating this.

Code for step 2: Here’s the Powershell code. Note, you will only have to change the “PLACEHOLDER” value.

$micStatus="Enabled"
$Key = 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\MMDevices\Audio\Capture\{PLACEHOLDER}'

if(Test-Path $key){
	$item = Get-ItemProperty -path $Key -Name DeviceState
	$item.DeviceState
}
else
{
	Write-Host 'path not found'
}
if( $item.DeviceState -Match "0")
        {
 
        Write-Host 'Mic Enabled'
                Set-ItemProperty -Path $Key -Name "DeviceState" -Value '1' -Force | Out-Null
				$micStatus="Enabled"
        }
else
 
        {
        Write-Host 'Mic Disabled'
 
                Set-ItemProperty -Path $Key -Name "DeviceState" -Value '10000001' -Force | Out-Null
				$micStatus="Disabled"
 
        }
		
Add-Type -AssemblyName System.Windows.Forms
$global:balmsg = New-Object System.Windows.Forms.NotifyIcon
$path = (Get-Process -id $pid).Path
$balmsg.Icon = [System.Drawing.Icon]::ExtractAssociatedIcon($path)
$balmsg.BalloonTipIcon = [System.Windows.Forms.ToolTipIcon]::Warning
$balmsg.BalloonTipText = 'Mic status of apps not updated'
$balmsg.BalloonTipTitle = "Microphone $micStatus"
$balmsg.Visible = $true
$balmsg.ShowBalloonTip(50000)

“mute.bat” code for Step 3

powershell.exe -executionpolicy bypass -file "C:\Users\C\Documents\work\mute.ps1"

Step: 4 – Error message you will see if you don’t update permissions.

You may likely get the above error message when you attempt to run the PowerShell script directly. In this case, you will need to update the Owner within the registry. After doing this your script should work properly.

Before mapping the mute.bat script to the keyboard, attempt running the script by double clicking the .bat file. After the script executes, you should see a notification message at the bottom right of Windows. You can also see the notification if you expand the notifications Window. Screenshot below. Navigate to sound settings to ensure the microphone was indeed disabled.

screenshot of microphone disabled notification — Screenshot of microphone disabled notification

screenshot of Windows 10 sound menu — Navigate to Sound setting by right clicking on the speaker icon in your toolbar then selecting “Open Sound settings”

Screenshot of Microphone when it still enabled.

Windows 10 Screenshot of Microphone disabled — Screenshot of Microphone when it is disabled. Notice, the input device is missing.

This script can also be retro fitted to disable web cams with a single keyboard press. You’ll just need to identify the registry values for the webcam. Dr Scripto also has an alternative method for disabling the webcam.