Group Adapters by their categories

Resolves https://github.com/pion/mediadevices/issues/22 Created 2 new directories under driver, camera and microphone. Moved camera_linux.go and microphone_linux.go appropriately. Imported driver/camera and driver/microphone by default.
2026-04-23 00:07:29 +08:00 · 2020-02-09 09:17:17 -08:00
parent 152f15526b
commit d8eda2db81
3 changed files with 8 additions and 4 deletions
@@ -0,0 +1,138 @@
+package camera
+
+// #include <linux/videodev2.h>
+import "C"
+
+import (
+	"image"
+	"io"
+
+	"github.com/blackjack/webcam"
+	"github.com/pion/mediadevices/pkg/driver"
+	"github.com/pion/mediadevices/pkg/frame"
+	"github.com/pion/mediadevices/pkg/io/video"
+	"github.com/pion/mediadevices/pkg/prop"
+)
+
+// Camera implementation using v4l2
+// Reference: https://linuxtv.org/downloads/v4l-dvb-apis/uapi/v4l/videodev.html#videodev
+type camera struct {
+	path            string
+	cam             *webcam.Webcam
+	formats         map[webcam.PixelFormat]frame.Format
+	reversedFormats map[frame.Format]webcam.PixelFormat
+	started         bool
+}
+
+func init() {
+	// TODO: Probably try to get more cameras
+	// Get default camera
+	defaultCam := newCamera("/dev/video0")
+
+	driver.GetManager().Register(defaultCam)
+}
+
+func newCamera(path string) *camera {
+	formats := map[webcam.PixelFormat]frame.Format{
+		webcam.PixelFormat(C.V4L2_PIX_FMT_YUYV):  frame.FormatYUYV,
+		webcam.PixelFormat(C.V4L2_PIX_FMT_NV12):  frame.FormatNV21,
+		webcam.PixelFormat(C.V4L2_PIX_FMT_MJPEG): frame.FormatMJPEG,
+	}
+
+	reversedFormats := make(map[frame.Format]webcam.PixelFormat)
+	for k, v := range formats {
+		reversedFormats[v] = k
+	}
+
+	return &camera{
+		path:            path,
+		formats:         formats,
+		reversedFormats: reversedFormats,
+	}
+}
+
+func (c *camera) Open() error {
+	cam, err := webcam.Open(c.path)
+	if err != nil {
+		return err
+	}
+
+	c.cam = cam
+	return nil
+}
+
+func (c *camera) Close() error {
+	if c.cam == nil {
+		return nil
+	}
+
+	if c.started {
+		c.cam.StopStreaming()
+	}
+	c.cam.Close()
+	return nil
+}
+
+func (c *camera) VideoRecord(p prop.Media) (video.Reader, error) {
+	decoder, err := frame.NewDecoder(p.FrameFormat)
+	if err != nil {
+		return nil, err
+	}
+
+	pf := c.reversedFormats[p.FrameFormat]
+	_, _, _, err = c.cam.SetImageFormat(pf, uint32(p.Width), uint32(p.Height))
+	if err != nil {
+		return nil, err
+	}
+
+	if err := c.cam.StartStreaming(); err != nil {
+		return nil, err
+	}
+	c.started = true
+
+	r := video.ReaderFunc(func() (img image.Image, err error) {
+		// Wait until a frame is ready
+		for {
+			err := c.cam.WaitForFrame(5)
+			switch err.(type) {
+			case nil:
+			case *webcam.Timeout:
+				continue
+			default:
+				// Camera has been stopped.
+				return nil, io.EOF
+			}
+
+			b, err := c.cam.ReadFrame()
+			if err != nil {
+				// Camera has been stopped.
+				return nil, io.EOF
+			}
+
+			// Frame is not ready.
+			if len(b) == 0 {
+				continue
+			}
+
+			return decoder.Decode(b, p.Width, p.Height)
+		}
+	})
+
+	return r, nil
+}
+
+func (c *camera) Properties() []prop.Media {
+	properties := make([]prop.Media, 0)
+	for format := range c.cam.GetSupportedFormats() {
+		for _, frameSize := range c.cam.GetSupportedFrameSizes(format) {
+			properties = append(properties, prop.Media{
+				Video: prop.Video{
+					Width:       int(frameSize.MaxWidth),
+					Height:      int(frameSize.MaxHeight),
+					FrameFormat: c.formats[format],
+				},
+			})
+		}
+	}
+	return properties
+}