[Performous-commit] Tapio Vierros : Threaded webcam - much better framerate.

[Tapio V. <aa...@us...>]

Module: performous
Branch: master
Commit: ca00c323c43e578cd5553f5ca0bc1545494a6907

Author: Tapio Vierros <tap...@gm...>
Date:   Sun May  9 23:24:47 2010 +0300

Threaded webcam - much better framerate.

---

 game/screen_sing.cc |    7 +++--
 game/webcam.cc      |   52 +++++++++++++++++++++++++++++++++++++++-----------
 game/webcam.hh      |   28 +++++++++++++++++++++++---
 3 files changed, 68 insertions(+), 19 deletions(-)

diff --git a/game/screen_sing.cc b/game/screen_sing.cc
index fec2a0c..20d5549 100644
--- a/game/screen_sing.cc
+++ b/game/screen_sing.cc
@@ -248,7 +248,8 @@ void ScreenSing::manageEvent(SDL_Event event) {
 		if (key == SDLK_k) dispInFlash(++config["game/karaoke_mode"]); // Toggle karaoke mode
 		if (key == SDLK_w) dispInFlash(++config["game/pitch"]); // Toggle pitch wave
 		#ifdef USE_OPENCV
-		if (key == SDLK_a) dispInFlash(++config["graphic/webcam"]); // Toggle webcam
+		// Toggle webcam
+		if (key == SDLK_a) { dispInFlash(++config["graphic/webcam"]); m_cam->pause(!config["graphic/webcam"].b()); }
 		#endif
 		// Latency settings
 		if (key == SDLK_F1) dispInFlash(--config["audio/video_delay"]);
@@ -306,9 +307,9 @@ void ScreenSing::draw() {
 			m_background->draw();
 		} else fillBG();
 		// Video
-		if (m_video && !m_cam && !(*m_cam)()) { m_video->render(time); double tmp = m_video->dimensions().ar(); if (tmp > 0.0) ar = tmp; }
+		if (m_video && !m_cam && !m_cam->is_good()) { m_video->render(time); double tmp = m_video->dimensions().ar(); if (tmp > 0.0) ar = tmp; }
 		// Webcam
-		if (m_cam && config["graphic/webcam"].b()) m_cam->render(time);
+		if (m_cam && config["graphic/webcam"].b()) m_cam->render();
 		// Top/bottom borders
 		ar = clamp(ar, arMin, arMax);
 		double offset = 0.5 / ar + 0.2;
diff --git a/game/webcam.cc b/game/webcam.cc
index aa35dd0..e9877df 100644
--- a/game/webcam.cc
+++ b/game/webcam.cc
@@ -1,35 +1,63 @@
 #include <iostream>
 
 #include "webcam.hh"
+#include "xtime.hh"
 
-Webcam::Webcam(int cam_id): m_capture(NULL), m_timestamp(0) {
+Webcam::Webcam(int cam_id):
+  m_capture(NULL), m_frameAvailable(false), m_running(false), m_quit(false)
+  {
 	#ifdef USE_OPENCV
 	m_capture = cvCaptureFromCAM(cam_id);
-	if (!m_capture)
+	if (!m_capture) {
 		std::cout << "Could not initialize webcam capturing!" << std::endl;
+		return;
+	}
+	m_thread.reset(new boost::thread(boost::ref(*this)));
 	#else
 	++cam_id; // dummy
 	#endif
 }
 
 Webcam::~Webcam() {
+	m_quit = true;
 	#ifdef USE_OPENCV
+	m_thread->join();
 	cvReleaseCapture(&m_capture);
 	#endif
 }
 
-void Webcam::render(double time) {
+void Webcam::operator()() {
 	#ifdef USE_OPENCV
-	if (!m_capture) return;
-	IplImage* frame = 0;
-	if (time > m_timestamp + 0.5) {
-		frame = cvQueryFrame(m_capture);
-		if (!frame) return;
-		m_surface.load(frame->width, frame->height, pix::RGB, (const unsigned char*)frame->imageData);
-		m_timestamp = time;
+	m_running = true;
+	while (!m_quit) {
+		IplImage* frame = 0;
+		if (m_running) frame = cvQueryFrame(m_capture);
+		if (frame) {
+			boost::mutex::scoped_lock l(m_mutex);
+			m_frame.width = frame->width;
+			m_frame.height = frame->height;
+			m_frame.data.assign(frame->imageData, frame->imageData + (m_frame.width * m_frame.height * 3));
+			m_frameAvailable = true;
+		}
+		boost::thread::sleep(now() + (m_running ? 0.05 : 0.5));
+	}
+	#endif
+}
+
+void Webcam::pause(bool do_pause) {
+	boost::mutex::scoped_lock l(m_mutex);
+	m_running = !do_pause;
+	m_frameAvailable = false;
+}
+
+void Webcam::render() {
+	#ifdef USE_OPENCV
+	if (!m_capture || !m_running) return;
+	if (m_frameAvailable && !m_frame.data.empty()) {
+		boost::mutex::scoped_lock l(m_mutex);
+		m_surface.load(m_frame.width, m_frame.height, pix::RGB, &m_frame.data[0]);
+		m_frameAvailable = false;
 	}
 	m_surface.draw();
-	#else
-	++time; // dummy
 	#endif
 }
diff --git a/game/webcam.hh b/game/webcam.hh
index b64bece..a5c17b5 100644
--- a/game/webcam.hh
+++ b/game/webcam.hh
@@ -7,8 +7,18 @@
 typedef void CvCapture;
 #endif
 
+#include <boost/scoped_ptr.hpp>
+#include <boost/thread/mutex.hpp>
+#include <boost/thread/thread.hpp>
+
 #include "surface.hh"
 
+struct CamFrame {
+	int width;
+	int height;
+	std::vector<uint8_t> data;
+};
+
 class Webcam {
   public:
 	/// cam_id -1 means pick any device
@@ -16,16 +26,26 @@ class Webcam {
 
 	~Webcam();
 
-	/// Is good?
-	bool operator()() { return m_capture != 0; }
+	/// Thread runs here, don't call directly
+	void operator()();
 
-	void render(double time);
+	/// Is good?
+	bool is_good() { return m_capture != 0; }
+	/// When paused, does not get or render frames
+	void pause(bool do_pause = true);
+	/// Display frame
+	void render();
 
 	Dimensions& dimensions() { return m_surface.dimensions; }
 	Dimensions const& dimensions() const { return m_surface.dimensions; }
 
   private:
+	boost::scoped_ptr<boost::thread> m_thread;
+	mutable boost::mutex m_mutex;
 	CvCapture* m_capture;
+	CamFrame m_frame;
 	Surface m_surface;
-	double m_timestamp;
+	bool m_frameAvailable;
+	volatile bool m_running;
+	volatile bool m_quit;
 };