In this article I will explain with an example, how to switch between front and back camera while capturing image (photo) from Web Camera (Webcam) using
jQuery in ASP.Net with C# and VB.Net.
jQuery Webcam Plugin
This article uses
jQuery Webcam plugin is used to capture images (photos) from Web Camera (Webcam).
HTML Markup
The HTML Markup consist of following elements:
div – For displaying Live Web Camera.
Image – For displaying the captured image.
Button – For capturing the picture using the Web Camera and one for uploading in the Folder (Directory).
<table border="0" cellpadding="0" cellspacing="0">
<tr>
<th align="center"><u>Live Camera</u></th>
<th align="center"><u>Captured Picture</u></th>
</tr>
<tr>
<td><div id="webcam"></div></td>
<td><img id="imgCapture" /></td>
</tr>
<tr>
<td align = "center">
<input type="button" id="btnFrontBack" value="Back" />
<input type="button" id="btnCapture" value="Capture" />
</td>
<td align = "center">
<input type="button" id="btnUpload" value="Upload" disabled="disabled" />
</td>
</tr>
</table>
The jQuery Webcam Plugin Client Side implementation
Inside the HTML Markup, the following Script files are inherited.
1. jquery.min.js
2. webcam.js
Capturing the Image from Web Camera (Webcam)
When the
Capture Button is clicked, the Image is captured from Web Camera (Webcam) using the
snap function of the
jQuery Webcam.js plugin.
Then, the captured Image data in BASE64 string format is assigned to the HTML Image element.
Switching the facing mode of Web Camera (Webcam)
When
Switch Button is clicked, the facingmode of
jQuery Webcam.js plugin is switched.
facingMode has following two options:
environment – To access the rear camera.
user - To access the front camera. It is by default if not set.
Uploading the Image from Web Camera (Webcam)
When the
Upload Button is clicked, the captured Image data in BASE64 string format is uploaded to Server using
jQuery AJAX call and then inside the
WebMethod, it is converted into Image file and saved in Folder (Directory).
Applying the jQuery Webcam.js plugin
Inside the
jQuery document ready event handler, the
jQuery Webcam plugin is applied to the HTML
div.
The following are the configuration properties of the
jQuery Webcam plugin.
width – Width of the DIV that displays the live camera.
height – Height of the DIV that displays the live camera.
image_format – The file format of the Image i.e. JPEG, PNG, etc.
jpeg_quality – The quality of the captured Image.
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/webcamjs/1.0.26/webcam.js"></script>
<script type="text/javascript">
$(function () {
ApplyPlugin();
$("#btnCapture").click(function () {
Webcam.snap(function (data_uri) {
$("#imgCapture")[0].src = data_uri;
$("#btnUpload").removeAttr("disabled");
});
});
$("#btnFrontBack").click(function () {
$('#btnFrontBack').val($('#btnFrontBack').val() == 'Back' ? 'Front' : 'Back');
Webcam.reset();
ApplyPlugin();
});
$("#btnUpload").click(function () {
$.ajax({
type: "POST",
url: "Default.aspx/SaveCapturedImage",
data: "{data: '" + $("#imgCapture")[0].src + "'}",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (r) { }
});
});
});
function ApplyPlugin() {
var mode = $('#btnFrontBack').val() == 'Back' ? 'user' : 'environment';
Webcam.set({
width: 320,
height: 240,
image_format: 'jpeg',
jpeg_quality: 90,
constraints: { facingMode: mode }
});
Webcam.attach('#webcam');
}
</script>
Namespaces
You will need to import the following namespaces.
C#
using System.IO;
using System.Web.Services;
VB.Net
Imports System.IO
Imports System.Web.Services
Saving image on Server Side using Web Method
The following
WebMethod is called using
jQuery AJAX after the Image (Photo) is captured and uploaded.
Inside the
SaveCapturedImage WebMethod, a current date time is set using
DateTime class which will be the name of the captured image.
The
WebMethod accepts the captured Image file data in BASE64 string format.
The BASE64 string is converted into a BYTE Array and the BYTE Array is saved as Image file in the Folder (Directory).
Note: The method is declared as
static (C#) and
Shared (VB.Net) and also it is declared as
WebMethod unless you do this you won�t be able to call the methods.
C#
[WebMethod]
public static bool SaveCapturedImage(string data)
{
string fileName = DateTime.Now.ToString("dd-MM-yy hh-mm-ss");
//Convert Base64 Encoded string to Byte Array.
byte[] imageBytes = Convert.FromBase64String(data.Split(',')[1]);
//Save the Byte Array as Image File.
string filePath = HttpContext.Current.Server.MapPath(string.Format("~/Captures/{0}.jpg", fileName));
File.WriteAllBytes(filePath, imageBytes);
return true;
}
VB.Net
<WebMethod>
Public Shared Function SaveCapturedImage(ByVal data As String) As Boolean
Dim fileName As String = DateTime.Now.ToString("dd-MM-yy hh-mm-ss")
'Convert Base64 Encoded string to Byte Array.
Dim imageBytes() As Byte = Convert.FromBase64String(data.Split(",")(1))
'Save the Byte Array as Image File.
Dim filePath As String = HttpContext.Current.Server.MapPath(String.Format("~/Captures/{0}.jpg", fileName))
File.WriteAllBytes(filePath, imageBytes)
Return True
End Function
Screenshot
![Switch between Front and Back camera in WebCam using jQuery in ASP.Net]()
Browser Compatibility
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Demo
Downloads
