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c# VLC.Dotnet play and then pause issue

I hope someone will be able to help me with my issue. i want to take a screenshot of the video at a specific time index, however when i try to change the time all i get is a blank black screen. i added buttons which play and pause, it allows me to play and pause the video, if i do that and then change the time index, i get an image. im confused as to why it doesn’t work using code. i even preform btnplay.PeformClick(); to play the video and when i do btnpause.PerformClick() to pause the video it doesn’t.
it seems that i can only get an image of the video if i have to physically hit the play and then pause button on my form, im trying to achieve this using code
private void Form1_Load(object sender, EventArgs e)
{
////////////////////LC4 VLC Settings///////////////////////////////////////////////////////////////////////////////////////////
control = new VlcControl();
var currentAssembly = Assembly.GetEntryAssembly();
var currentDirectory = new FileInfo(currentAssembly.Location).DirectoryName;
var libDirectory = new DirectoryInfo(Path.Combine(currentDirectory, "libvlc", IntPtr.Size == 4 ? "win-x86" : "win-x64"));
control.BeginInit();
control.VlcLibDirectory = libDirectory;
control.Dock = DockStyle.Fill;
control.EndInit();
panel1.Controls.Add(control);
main_form_LC4_data();
}
void main_form_LC4_data()
{
long vOut3 = 20;
playfile("path to file");
First_Frame(vOut3);
}
void playfile(string final)
{
control.SetMedia(new Uri(final).AbsoluteUri);
control.Time = 0;
control.Update();
}
void First_Frame(long vOut3)
{
control.Time = vOut3;
}
private void button9_Click(object sender, EventArgs e)
{
control.Play();
Console.WriteLine("PLAY");
}
private void button8_Click(object sender, EventArgs e)
{
control.Pause();
Console.WriteLine("PAUSE");
}
Above is my code in a nut shell
i have tried things like this
private void button10_Click(object sender, EventArgs e)
{
First_Frame(first_frame); // jump to index
}
and then calling up button10.PerformClick(); however it doesnt seem to work. once again if i physically hit the buttons on my form it works perfectly, however not in the way of coding it.
as an example :
play.PeformClick();
Pause.PeformClick();
time = vOut3;
I do hope this isnt to confusing im really stuck and am still hoping someone can help me
Thank you

A few things:
control.Update();
this does nothing.
You need to wait for the Playing event to be raised after setting the time, otherwise libvlc doesn't have the time to decode the frame and display it (setting the time is asynchronous)

Changing label text on button click that also executes other methods

I am trying to update a label on my windows form with statistics from another methods execution that scrapes a webpage and creates a zip file of the links and creates a sitemap page. Preferably this button would run the scraping operations and report the statistics properly. Currently the scraping process is working fine but the label I want to update with statistics data is not changing on the button click. Here is what my code looks like now:
protected void btn_click(object sender, EventArgs e)
{
//Run scrape work
scrape_work(sender, e);
//Run statistics work
statistics(sender, e);
}
protected void scrape_work(object sender, EventArgs e)
{
//Scraping work (works fine)
}
protected void statistics(object sender, EventArgs e)
{
int count = 0;
if (scriptBox.Text != null)
{
count += 1;
}
var extra = eventsBox.Text;
var extraArray = extra.Split('\n');
foreach (var item in extraArray)
{
count += 1;
}
//scrapeNumLbl is label I want to display text on
scrapeNumLbl.Text = count.ToString();
}
Would I have to use threading for this process or is there some other way I can get this process to work? I have already tried this solution but was having the same issue where the code runs but the label does not update. Any help would be greatly appreciated, this minor thing has been bugging me for hours now.

I eventually solved this by writing the path to the zip file to a label button on the form rather than sending it right to download on the client's browser on button click. The issue was that the request was ending after the zip file was sent for download. To ensure that both methods ran at the proper time I moved the call to the scrape_work method to inside of of statistics
In order for the path to be clickable and the file to download properly I had to make the "label" in the form a LinkButton in the .aspx page
<asp:LinkButton ID="lblDownload" runat="server" CssClass="xclass" OnClick="lblDownload_Click"></asp:LinkButton>
And made the lblDownload_Click run like the following:
Response.Clear();
Response.BufferOutput = false;
Response.ContentType = "application/zip";
Response.AddHeader("content-disposition", "attachment; filename=zipFiles.zip");
string folder = Server.MapPath("~/zip");
string endPath = folder + "/zipFiles.zip";
Response.TransmitFile(endPath);
Response.End();
Running it this way the page reloads with the new labels properly written and the zip file available to download as well.

ASSUMING THIS CODE IS RUNNING SYNCHRONOUSLY (you aren't threading the scraping in a call I don't see), Are you sure you are reaching the code that sets the label text? I simplified your code as below (removing the iteration over the array and just setting the label text to a stringified integer) and am not having any trouble changing the text of a label.
namespace SimpleTest
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
scrape_work(sender, e);
statistics(sender, e);
}
protected void scrape_work(object sender, EventArgs e)
{
//Scraping work (works fine)
}
protected void statistics(object sender, EventArgs e)
{
int count = 666;
scrapeNumLbl.Text = count.ToString();
}
}
}
Result:

Cant view webcam after being ran once. C#

the title may sound confusing but ill explain it better here. Im making a program which displays the webcam capture in a picturebox using the "easy web cam" external reference. If i turn on my computer, go into VS, open the project and run, it will work, displaying my webcam capture. If i stop the program and then run it again, when i try to display it, i get a popup asking me to select a video source, none of the options is even my webcam and then another popup will appear saying
"An error ocurred while capturing the video image. The video capture will now be terminated.
Object reference not set to ann instance of an object"
The only thing i can think of is that the first time its setting up the camera but when i close it im not turning it off properly so when i run it again, it wont work. anyway heres the relevant code, bare in mind if answering, im not that experienced when coding so sometimes you might have to spell stuff out
using WebCam_Capture;
namespace WindowsWebRef
{
public partial class Frm_Main : Form
{
public Frm_Main()
{
InitializeComponent();
}
WebCam webcam;
private void button1_Click(object sender, EventArgs e)
{
webcam.Start();
}
private void Frm_Main_Load(object sender, EventArgs e)
{
webcam = new WebCam();
webcam.InitializeWebCam(ref WebCamIMG);
}
And the webcam class...
class WebCam
{
private WebCamCapture webcam;
private System.Windows.Forms.PictureBox _FrameImage;
private int FrameNumber = 30;
public void InitializeWebCam(ref System.Windows.Forms.PictureBox ImageControl)
{
webcam = new WebCamCapture();
webcam.FrameNumber = ((ulong)(0ul));
webcam.TimeToCapture_milliseconds = FrameNumber;
webcam.ImageCaptured += new WebCamCapture.WebCamEventHandler(webcam_ImageCaptured);
_FrameImage = ImageControl;
}
void webcam_ImageCaptured(object source, WebcamEventArgs e)
{
_FrameImage.Image = e.WebCamImage;
}
public void Start()
{
webcam.TimeToCapture_milliseconds = FrameNumber;
webcam.Start(0);
}

Restart your computer and be sure to add in webcam.Stop(); otherwise your program will hold on to the webcam and make it unavailable to use in any other application (or a different instance of the program.)

Previewing images in a listBox using pictureBox

I am using Winforms to create a 2D Map Editor.
I want to be able to preview an image of my assets that are stored in listBox using a pictureBox.
My current code for doing so is thus.
private void listBox_Assets_SelectedIndexChanged(object sender, EventArgs e)
{
pictureBox1.Image = Image.FromFile(((FileInfo)listBox_Assets.SelectedItem).FullName);
}
But when I select an asset I get this error.
Unable to cast object of type 'System.String' to type 'System.IO.FileInfo'.
I have searched high and low for a solution but can't find an answer to this error, any help would be greatly appreciated.

You use the file name from the listbox like this, and protect the code with a check for the file.
private void listBox_Assets_SelectedIndexChanged(object sender, EventArgs e)
{
string file = IO.Path.Combine("the directory", listBox_Assets.SelectedItem);
if (IO.File.Exists(file))
pictureBox1.Image = Image.FromFile(file);
}

How to capture image with webcam?

I want to capture image with webcam.
I use WebCam_Capture.dll. i add a WebCamCapture control in form.
when form load:
private void Form1_Load(object sender, EventArgs e)
{
this.WebCamCapture.TimeToCapture_milliseconds = 1;
WebCamCapture.Start(0);
}
and in ImageCaptured event :
private void WebCamCapture_ImageCaptured(object source,
WebCam_Capture.WebcamEventArgs e)
{
this.pictureBox1.Image = e.WebCamImage;
}
but when i run, i get error:
An error ocurred while capturing the video image. The video capture will now be terminated.
Object reference not set to an instance of an object.

I recommend you to use OpenCV Library.
it is an open source library for image proccessing from intel, developed by intel.
but, it has a wrapper for .net, you can download this wrapper from : this link