Add video file reader

video/video.go

@@ -0,0 +1,50 @@
+// Package video.
+package video
+
+import (
+	"fmt"
+	"image"
+
+	"github.com/lazywei/go-opencv/opencv"
+)
+
+// Video represents video.
+type Video struct {
+	video *opencv.Capture
+}
+
+// New returns new Video for given path.
+func New(filename string) (video *Video, err error) {
+	video = &Video{}
+
+	video.video = opencv.NewFileCapture(filename)
+	if video.video == nil {
+		err = fmt.Errorf("video: can not open video %s", filename)
+	}
+
+	return
+}
+
+// Read reads next frame from video and returns image.
+func (v *Video) Read() (img image.Image, err error) {
+	if v.video.GrabFrame() {
+		frame := v.video.RetrieveFrame(1)
+		img = frame.ToImage()
+	} else {
+		err = fmt.Errorf("video: can not grab frame")
+	}
+
+	return
+}
+
+// Close closes video.
+func (v *Video) Close() (err error) {
+	if v.video == nil {
+		err = fmt.Errorf("video: video is not opened")
+		return
+	}
+
+	v.video.Release()
+	v.video = nil
+	return
+}

video/video_test.go

@@ -0,0 +1,62 @@
+package video
+
+import (
+	"fmt"
+	"image/jpeg"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestVideo(t *testing.T) {
+	video, err := New("ranko.mp4")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer video.Close()
+
+	tmpdir, err := ioutil.TempDir(os.TempDir(), "cam2ip")
+	if err != nil {
+		t.Error(err)
+	}
+
+	defer os.RemoveAll(tmpdir)
+
+	var i int
+	var n int = 10
+
+	timeout := time.After(time.Duration(n) * time.Second)
+
+	for {
+		select {
+		case <-timeout:
+			//fmt.Printf("Fps: %d\n", i/n)
+			return
+		default:
+			i += 1
+
+			img, err := video.Read()
+			if err != nil {
+				t.Error(err)
+			}
+
+			file, err := os.Create(filepath.Join(tmpdir, fmt.Sprintf("%03d.jpg", i)))
+			if err != nil {
+				t.Error(err)
+			}
+
+			err = jpeg.Encode(file, img, &jpeg.Options{Quality: 75})
+			if err != nil {
+				t.Error(err)
+			}
+
+			err = file.Close()
+			if err != nil {
+				t.Error(err)
+			}
+		}
+	}
+}