Add support for native VFW implementation on Windows

camera/camera_linux.go

@@ -0,0 +1,132 @@
+// +build !cv2,!cv3
+
+// Package camera.
+package camera
+
+import (
+	"fmt"
+	"image"
+
+	"github.com/disintegration/imaging"
+	"github.com/korandiz/v4l"
+	"github.com/korandiz/v4l/fmt/mjpeg"
+
+	im "github.com/gen2brain/cam2ip/image"
+)
+
+// Options.
+type Options struct {
+	Index  int
+	Rotate int
+	Width  float64
+	Height float64
+}
+
+// Camera represents camera.
+type Camera struct {
+	opts   Options
+	camera *v4l.Device
+}
+
+// New returns new Camera for given camera index.
+func New(opts Options) (camera *Camera, err error) {
+	camera = &Camera{}
+	camera.opts = opts
+
+	devices := v4l.FindDevices()
+	if len(devices) < opts.Index+1 {
+		err = fmt.Errorf("camera: no camera at index %d", opts.Index)
+		return
+	}
+
+	camera.camera, err = v4l.Open(devices[opts.Index].Path)
+	if err != nil {
+		err = fmt.Errorf("camera: %s", err.Error())
+		return
+	}
+
+	if camera.camera == nil {
+		err = fmt.Errorf("camera: can not open camera %d", opts.Index)
+		return
+	}
+
+	config, err := camera.camera.GetConfig()
+	if err != nil {
+		err = fmt.Errorf("camera: %s", err.Error())
+		return
+	}
+
+	config.Format = mjpeg.FourCC
+	config.Width = int(opts.Width)
+	config.Height = int(opts.Height)
+
+	err = camera.camera.SetConfig(config)
+	if err != nil {
+		err = fmt.Errorf("camera: %s", err.Error())
+		return
+	}
+
+	err = camera.camera.TurnOn()
+	if err != nil {
+		err = fmt.Errorf("camera: %s", err.Error())
+		return
+	}
+
+	return
+}
+
+// Read reads next frame from camera and returns image.
+func (c *Camera) Read() (img image.Image, err error) {
+
+	buffer, err := c.camera.Capture()
+	if err != nil {
+		err = fmt.Errorf("camera: can not grab frame: %s", err.Error())
+		return
+	}
+
+	img, err = im.NewDecoder(buffer).Decode()
+	if err != nil {
+		err = fmt.Errorf("camera: %s", err.Error())
+		return
+	}
+
+	if c.opts.Rotate == 0 {
+		return
+	}
+
+	switch c.opts.Rotate {
+	case 90:
+		img = imaging.Rotate90(img)
+	case 180:
+		img = imaging.Rotate180(img)
+	case 270:
+		img = imaging.Rotate270(img)
+	}
+
+	return
+}
+
+// GetProperty returns the specified camera property.
+func (c *Camera) GetProperty(id int) float64 {
+	ret, _ := c.camera.GetControl(uint32(id))
+	return float64(ret)
+}
+
+// SetProperty sets a camera property.
+func (c *Camera) SetProperty(id int, value float64) {
+	c.camera.SetControl(uint32(id), int32(value))
+}
+
+// Close closes camera.
+func (c *Camera) Close() (err error) {
+	if c.camera == nil {
+		err = fmt.Errorf("camera: camera is not opened")
+		return
+	}
+
+	c.camera.TurnOff()
+
+	c.camera.Close()
+	c.camera = nil
+	return
+}