webcam

README

webcam

This activity provides your flogo application the ability to take pictures with a USB connected Webcam. It is mandatory to specify the device Id, the image resolution as width and height and the compression factor. The image has a png format.

IMPORTANT
This activity uses the GoCV package that provides a binding for the OpenCV 4 computer vision library. Based on the specific OS, you need to install OpenCV 4 on your system, otherwise the activity will throw an exception.

The installation instructions can be found here: https://github.com/hybridgroup/gocv#how-to-install

Installation

flogo install activity github.com/achimera/flogo/activity/webcam

Schema

Settings and Outputs:

{
  "settings":[
    {
      "name": "deviceID",
      "type": "int",
      "required": true
	},
	{
      "name": "imageWidth",
      "type": "int",
      "required": true
	},
	{
      "name": "imageHeigth",
      "type": "int",
      "required": true
	},
	{
      "name": "compression",
      "type": "int",
      "allowed": [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
    }
  ],
  "outputs": [
    {
      "name": "image",
      "type": "[]byte"
	},
	{
      "name": "base64String",
      "type": "string"
    },
  	{
      "name": "status",
      "type": "string"
    }
  ]
}

Settings

Name	Type	Description
deviceID	int	The device id of the webcam. Usually the device id is 0 for onboard cameras
imageWidth	int	The resolution width of the image. Please check the resolutions that your webcam are supporting
imageHeigth	int	The resolution height of the image. Please check the resolutions that your webcam are supporting
compression	int	The compression factor of the png image. Value 0 is no compression, where 9 is the maximum compression and also the smallest size. Valid integer values are between 0 and 9. If not set or not in range, then the default compression of 3 is applied

Output

Name	Type	Description
image	[]byte	The captured image is returned as a byte array. No Base64 encoding is done.
base64String	string	The captured image is returned as a Base64 encoded string.
status	string	The status of the operation. "OK" is returned when the webcam successfully captured an image

Configuration Example

		{
			"id": "webcam",
			"name": "Take a picture from a Webcam",
			"description": "Webcam Activity",
			"activity": {
				"ref": "github.com/achimera/flogo/activity/webcam",
				"settings": {
					"deviceID": "0",
					"imageWidth": "1024",
					"imageHeigth": "720",
					"compression": "10"
				}
			}
		}

Documentation

Index

• func New(ctx activity.InitContext) (activity.Activity, error)
• type Activity
  • func (act *Activity) Eval(ctx activity.Context) (done bool, err error)
  • func (*Activity) Metadata() *activity.Metadata
• type Output
  • func (o *Output) FromMap(values map[string]interface{}) error
  • func (o *Output) ToMap() map[string]interface{}
• type Settings

Functions

func New

func New(ctx activity.InitContext) (activity.Activity, error)

New create a new activity

Types

type Activity

type Activity struct {
	// contains filtered or unexported fields
}

Activity is a kafka activity

func (*Activity) Eval

func (act *Activity) Eval(ctx activity.Context) (done bool, err error)

Eval implements the evaluation of the kafka activity

func (*Activity) Metadata

func (*Activity) Metadata() *activity.Metadata

Metadata returns the metadata for the kafka activity

type Output

type Output struct {
	Image        []byte `md:"image"`        // The byte array containing the image
	Base64String string `md:"base64String"` // The Base64 encoded byte array returned as a string
	Status       string `md:"status"`       // Status of the webcam
}

func (*Output) FromMap

func (o *Output) FromMap(values map[string]interface{}) error

func (*Output) ToMap

func (o *Output) ToMap() map[string]interface{}

type Settings

type Settings struct {
	DeviceID    string `md:"deviceID, required"`                                 // The webcam deviceId
	ImageWidth  int    `md:"imageWidth, required"`                               // The image resolution width
	ImageHeigth int    `md:"imageHeigth, required"`                              // The image resolution heigth
	Compression int    `md:"compression, allowed(0, 1, 2, 3, 4, 5, 6, 7, 8, 9)"` // The image compression factor
}