cam

README

cam

cam is a package for Go that provides a high level api (similar to net/http) and a small set of plugins for working with camera frames. For the device communication, implementing the Device interface, we use GoCV and OpenCV, more can be easily added. Contributions are welcomed.

Dependencies

• For the gocv device implementation you will only need OpenCV installed. You can see instructions for installation on the opencv docs and in the GoCV page.

Installation

go get github.com/mvrilo/cam

Example

package main

import (
	"image"
	"image/color"
	"log"

	"github.com/mvrilo/cam"
	"github.com/mvrilo/cam/middlewares/pixelize"
	"github.com/mvrilo/cam/middlewares/window"
	"gocv.io/x/gocv"

	_ "github.com/mvrilo/cam/gocv"
)

func main() {
	cam.Use(pixelize.New(32))
	cam.Handle(func(f cam.Frame) {
		text := "hello world"
		blue := color.RGBA{0, 0, 255, 0}
		data, ok := f.Data().(gocv.Mat)
		if !ok {
			return
		}
		gocv.PutText(&data, text, image.Pt(200, 200), gocv.FontHersheyPlain, 10, blue, 8)
	})
	cam.Use(window.New("cam example"))
	log.Fatal(cam.ListenAndServe(0, nil))
}

Author

Murilo Santana <mvrilo@gmail.com>

Documentation

Index

• func Handle(f func(f Frame))
• func ListenAndServe(addr interface{}, handler Handler) error
• func Register(device Device)
• func Use(h ...Handler)
• type Cam
  • func (c *Cam) Close() error
  • func (c *Cam) Handle(h func(Frame))
  • func (c *Cam) ListenAndServe() error
  • func (c *Cam) Register(video Device)
  • func (c *Cam) Serve()
  • func (c *Cam) Use(handlers ...Handler)
• type Device
• type Frame
• type Handler
• type HandlerFunc
  • func (h HandlerFunc) Handle(frame Frame)
• type Storage
• type Store
  • func NewStore() *Store
  • func (s *Store) Get(name string) interface{}
  • func (s *Store) Set(name string, val interface{})

Functions

func Handle

func Handle(f func(f Frame))

func ListenAndServe

func ListenAndServe(addr interface{}, handler Handler) error

func Register

func Register(device Device)

func Use

func Use(h ...Handler)

Types

type Cam

type Cam struct {
	Addr     interface{}
	Device   Device
	Handlers []Handler
}

Cam struct with the video, device address and a list of handlers

func (*Cam) Close

func (c *Cam) Close() error

func (*Cam) Handle

func (c *Cam) Handle(h func(Frame))

Handle appends to the list of handlers a func with a signature that matches the HandlerFunc

func (*Cam) ListenAndServe

func (c *Cam) ListenAndServe() error

func (*Cam) Register

func (c *Cam) Register(video Device)

Register sets a video device

func (*Cam) Serve

func (c *Cam) Serve()

func (*Cam) Use

func (c *Cam) Use(handlers ...Handler)

Use appends to the list of handlers one or more Handlers

type Device

type Device interface {
	NewFrame() Frame
	Read(data interface{})
	Open(device interface{}) error
	Close() error
}

Device interfaces with the device

type Frame

type Frame interface {
	Storage
	Close()
	Data() interface{}
}

Frame interfaces with the device frame

type Handler

type Handler interface {
	Handle(Frame)
}

Handler interface expects a Handle func that receivs a frame

type HandlerFunc

type HandlerFunc func(Frame)

func (HandlerFunc) Handle

func (h HandlerFunc) Handle(frame Frame)

type Storage

type Storage interface {
	Get(key string) interface{}
	Set(key string, value interface{})
}

Storage interface

type Store

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

Store is a concurrency-safe map[string]interface{} implemntation

func NewStore

func NewStore() *Store

func (*Store) Get

func (s *Store) Get(name string) interface{}

Get returns a value as interface{} from its store

func (*Store) Set

func (s *Store) Set(name string, val interface{})

Set writes a value on its store for a given name