func calibrate(videoFile string, config Configuration) {
// It takes a little while for the white balance to stabalise on the logitech.
// So grab a frame, wait to stabalise for white balance to stabalise, then grab again
// for and save as the calibration frame.
camera, err := getVideoSource(videoFile)
if err != nil {
// No valid video source, abort.
log.Printf("ERROR: Unable to get video source")
log.Print(err)
return
}
calibrationFrame := C.cvQueryFrame(camera)
time.Sleep(1250 * time.Millisecond)
C.cvReleaseCapture(&camera)
camera, err = getVideoSource(videoFile)
if err != nil {
// No valid video source, abort
log.Printf("ERROR: Unable to get video source")
log.Print(err)
return
}
defer C.cvReleaseCapture(&camera)
// Build the calibration image from the first frame that comes off the camera.
calibrationFrame = C.cvQueryFrame(camera)
fileName := "calibrationFrame.jpg"
file := C.CString(fileName)
C.cvSaveImage(file, unsafe.Pointer(calibrationFrame), nil)
C.free(unsafe.Pointer(file))
// Broadcast calibration results to the mothership.
f, err := os.Open(fileName)
if err != nil {
log.Printf("ERROR: Unable to open calibration frame to broadcast")
log.Print(err)
return
}
defer f.Close()
post(fileName, config.MothershipAddress+"/scout_api/calibrated", config.UUID, f)
}
/* stop capturing/reading and free resources */
func (capture *Capture) Release() {
cap_c := (*C.CvCapture)(capture)
C.cvReleaseCapture(&cap_c)
}
func measure(deltaC chan Command, videoFile string, debug bool, config Configuration) {
camera, err := getVideoSource(videoFile)
if err != nil {
// No valid video source. Abort measuring.
log.Printf("ERROR: Unable to get video source")
log.Print(err)
return
}
defer C.cvReleaseCapture(&camera)
// Make sure we release the camera when the operating system crushes us.
c := make(chan os.Signal, 1)
signal.Notify(c, os.Interrupt)
go func() {
<-c
log.Printf("INFO: The OS shut down the scout.")
C.cvReleaseCapture(&camera)
return
}()
scene := initScene()
// Build the calibration frame from disk.
var calibrationFrame *C.IplImage
if _, err := os.Stat("calibrationFrame.jpg"); err == nil {
file := C.CString("calibrationFrame.jpg")
calibrationFrame = C.cvLoadImage(file, C.CV_LOAD_IMAGE_COLOR)
defer C.cvReleaseImage(&calibrationFrame)
C.free(unsafe.Pointer(file))
} else {
log.Printf("ERROR: Unable to measure, missing calibration frame")
log.Print(err)
return
}
// Create a frame to hold the foreground mask results.
mask := C.cvCreateImage(C.cvSize(calibrationFrame.width, calibrationFrame.height), C.IPL_DEPTH_8U, 1)
defer C.cvReleaseImage(&mask)
// Push the initial calibration frame into the MOG2 image subtractor.
C.initMOG2(C.int(config.MogHistoryLength), C.double(config.MogThreshold), C.int(config.MogDetectShadows))
C.applyMOG2(unsafe.Pointer(calibrationFrame), unsafe.Pointer(mask))
// Current frame counter.
frame := int64(0)
measuring := true
// Start monitoring from the camera.
for measuring && C.cvGrabFrame(camera) != 0 {
// See if there are any new commands on the deltaC channel.
select {
case c := <-deltaC:
switch {
case c == STOP_MEASURE:
log.Printf("INFO: Stopping measure")
measuring = false
}
default:
// Procceed with measuring.
}
// Subtract the calibration frame from the current frame.
nextFrame := C.cvRetrieveFrame(camera, 0)
C.applyMOG2(unsafe.Pointer(nextFrame), unsafe.Pointer(mask))
// Filter the foreground mask to clean up any noise or holes (morphological-closing).
C.cvSmooth(unsafe.Pointer(mask), unsafe.Pointer(mask), C.CV_GAUSSIAN, C.int(config.GaussianSmooth), 0, 0.0, 0.0)
C.cvThreshold(unsafe.Pointer(mask), unsafe.Pointer(mask), C.double(config.ForegroundThresh), 255, 0)
C.cvDilate(unsafe.Pointer(mask), unsafe.Pointer(mask), nil, C.int(config.DilationIterations))
// Detect contours in filtered foreground mask
storage := C.cvCreateMemStorage(0)
contours := C.cvCreateSeq(0, C.size_t(unsafe.Sizeof(C.CvSeq{})), C.size_t(unsafe.Sizeof(C.CvPoint{})), storage)
offset := C.cvPoint(C.int(0), C.int(0))
num := int(C.cvFindContours(unsafe.Pointer(mask), storage, &contours, C.int(unsafe.Sizeof(C.CvContour{})),
C.CV_RETR_LIST, C.CV_CHAIN_APPROX_SIMPLE, offset))
var detectedObjects []Waypoint
// Track each of the detected contours.
for contours != nil {
area := float64(C.cvContourArea(unsafe.Pointer(contours), C.cvSlice(0, 0x3fffffff), 0))
// Only track large objects.
if area > config.MinArea {
boundingBox := C.cvBoundingRect(unsafe.Pointer(contours), 0)
w := int(boundingBox.width / 2)
h := int(boundingBox.height / 2)
x := int(boundingBox.x) + w
y := int(boundingBox.y) + h
detectedObjects = append(detectedObjects, Waypoint{x, y, w, h, 0.0})
if debug {
// DEBUG -- Render contours and bounding boxes around detected objects.
pt1 := C.cvPoint(boundingBox.x, boundingBox.y)
pt2 := C.cvPoint(boundingBox.x+boundingBox.width, boundingBox.y+boundingBox.height)
C.cvDrawContours(unsafe.Pointer(nextFrame), contours, C.cvScalar(12.0, 212.0, 250.0, 255), C.cvScalar(0, 0, 0, 0), 2, 1, 8, offset)
C.cvRectangle(unsafe.Pointer(nextFrame), pt1, pt2, C.cvScalar(16.0, 8.0, 186.0, 255), C.int(5), C.int(8), C.int(0))
}
} else {
num--
}
contours = contours.h_next
}
scene.update(detectedObjects, debug, config)
C.cvClearMemStorage(storage)
C.cvReleaseMemStorage(&storage)
if debug {
var font C.CvFont
C.cvInitFont(&font, C.CV_FONT_HERSHEY_SIMPLEX, C.double(0.5), C.double(0.5), C.double(1.0), C.int(2), C.CV_AA)
txt := C.CString("Hello friend.")
C.cvPutText(unsafe.Pointer(nextFrame), txt, C.cvPoint(2, 2), &font, C.cvScalar(255.0, 255.0, 255.0, 255))
C.free(unsafe.Pointer(txt))
// DEBUG -- render current interaction path for detected objects.
for _, i := range scene.Interactions {
for _, w := range i.Path {
pt1 := C.cvPoint(C.int(w.XPixels), C.int(w.YPixels))
C.cvCircle(unsafe.Pointer(nextFrame), pt1, C.int(10), C.cvScalar(109.0, 46.0, 0.0, 255), C.int(2), C.int(8), C.int(0))
}
w := i.lastWaypoint()
txt := C.CString(fmt.Sprintf("%01d", i.SceneID))
C.cvPutText(unsafe.Pointer(nextFrame), txt, C.cvPoint(C.int(w.XPixels+10), C.int(w.YPixels+10)), &font, C.cvScalar(255.0, 255.0, 255.0, 255))
C.free(unsafe.Pointer(txt))
}
for _, i := range scene.idleInteractions {
w := i.lastWaypoint()
pt1 := C.cvPoint(C.int(w.XPixels-w.HalfWidthPixels+5), C.int(w.YPixels-w.HalfHeightPixels+5))
pt2 := C.cvPoint(C.int(w.XPixels+w.HalfWidthPixels-5), C.int(w.YPixels+w.HalfHeightPixels-5))
C.cvRectangle(unsafe.Pointer(nextFrame), pt1, pt2, C.cvScalar(16.0, 186.0, 8.0, 255), C.int(5), C.int(8), C.int(0))
txt := C.CString("i:" + fmt.Sprintf("%01d", i.SceneID))
C.cvPutText(unsafe.Pointer(nextFrame), txt, C.cvPoint(C.int(w.XPixels+10), C.int(w.YPixels+10)), &font, C.cvScalar(255.0, 255.0, 255.0, 255))
C.free(unsafe.Pointer(txt))
}
file := C.CString("f" + fmt.Sprintf("%03d", frame) + "-detected.png")
C.cvSaveImage(file, unsafe.Pointer(nextFrame), nil)
C.free(unsafe.Pointer(file))
frame++
}
}
log.Printf("INFO: Finished measure")
scene.close(debug, config)
}
func (cap *Capture) Close() {
C.cvReleaseCapture(&cap.handler)
}