propertyInfo

Retrieve metadata for webcam properties

Since R2024a

Syntax

info = propertyInfo(cam)

info = propertyInfo(cam,propertyNames)

Description

info = propertyInfo(cam) returns the metadata information in info related to all the properties of the webcam object specified in cam.

info = propertyInfo(cam,propertyNames) returns the metadata information related to only the webcam properties specified in propertyNames. You can specify a single property or multiple properties in propertyNames.

Examples

Retrieve Metadata for All Properties

Find the name of your camera using the webcamlist function to ensure that MATLAB can discover your camera(s).

webcamlist

ans = 2×1 cell array
    {'Logitech Webcam C925e'          }
    {'Microsoft® LifeCam Cinema(TM)'}

Create a webcam object for your camera.

cam = webcam(1)

cam = 

  webcam with properties:

                    Name: 'Logitech Webcam C925e'
              Resolution: '1920x1080'
    AvailableResolutions: {'1920x1080'}

Use the propertyInfo function to retrieve the metadata for all properties supported by the webcam object.

info = propertyInfo(cam)

info = 

  1×3 PropertyInfo array with properties:

   PropertyInfo with properties:

             Name: "Name"
             Type: "string"
          Default: []
         ReadOnly: 1
    AllowedValues: []

   PropertyInfo with properties:

             Name: "AvailableResolutions"
             Type: "cell"
          Default: []
         ReadOnly: 1
    AllowedValues: []

   PropertyInfo with properties:

             Name: "Resolution"
             Type: "string"
          Default: []
         ReadOnly: 0
    AllowedValues: "1920x1080"

The propertyInfo does not return a default value for the Name, AvailableResolutions, and Resolution properties as the webcam object does not support default values for these properties.

Return Metadata for Multiple Properties

To retrieve the metadata for a single or multiple properties of webcam.

Find the name of your camera using the webcamlist function to ensure that MATLAB can discover your camera(s).

webcamlist

ans = 

  2×1 cell array  
    {'Logitech Webcam C925e'} 
    {'Webcam Test Device'   }

Create a webcam object for your camera.

cam = webcam(1)

cam =   

  webcam with properties: 

                     Name: 'Logitech Webcam C925e' 
               Resolution: '640x480' 
     AvailableResolutions: {1×19 cell} 
    BacklightCompensation: 0 
               Brightness: 128 
                 Contrast: 128 
                 Exposure: -5 
             ExposureMode: 'auto' 
                    Focus: 0 
                FocusMode: 'auto' 
                     Gain: 0 
                      Pan: 0 
               Saturation: 128 
                Sharpness: 128 
                     Tilt: 0 
             WhiteBalance: 4000
         WhiteBalanceMode: 'auto' 
                     Zoom: 100 

Use the propertyInfo function to retrieve the metadata for the Brightness property of the webcam object.

info = propertyInfo(cam,"Brightness")

info =  

  PropertyInfo with properties: 

             Name: "Brightness" 
             Type: "double" 
          Default: 128 
         ReadOnly: 0 
    AllowedValues: [0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 … ] (1×256 double) 

Use the propertyInfo function to retrieve the metadata for the Name and Sharpness properties of the webcam object.

info = propertyInfo(cam,["Name","Sharpness"])

infos =   

  1×2 PropertyInfo array with properties:  

   PropertyInfo with properties: 

             Name: "Name" 
             Type: "string" 
          Default: [] 
         ReadOnly: 1 
    AllowedValues: [] 

   PropertyInfo with properties:  

             Name: "Sharpness" 
             Type: "double" 
          Default: 128 
         ReadOnly: 0 
    AllowedValues: [0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 … ] (1×256 double) 

Input Arguments

cam — Hardware connection to a webcam

webcam object

Hardware connection to a webcam, specified as a webcam object.

propertyNames — Name of webcam property

string | character vector | string vector | character array

Name of webcam property or properties specified as 1-by-n vector of string or character array, where n <= N. N is the number of supported webcam properties.

Output Arguments

info — Property metadata

1-by-N array of propertyInfo objects.

Property metadata, returned as a 1-by-N array of propertyInfo objects containing property metadata. N is the number of supported webcam properties passed through the propertyInfo function. Each propertyInfo object contains five properties.

Properties of propertyInfo object

Property	Description
Name	Name of the webcam property stored as a string.
Type	Data type of the webcam property. This can be any fundamental data type or a user-defined data type supported by MATLAB®.
ReadOnly	Logical value indicating if the webcam property is read-only.
Default	Default value of the webcam property. The Default value depends on the type of webcam.
AllowedValues	Vector of valid string or numeric values for the webcam property. The AllowedValues property depends on the type of webcam.

Version History

Introduced in R2024a