Basic frame grab from camera; not currently working yet, but let's try on

OS X!

interface/src/Application.cpp

@@ -1567,6 +1567,9 @@ void Application::update(float deltaTime) {
     
     //  Update transmitter
     
+    //  Get the webcam frame
+    _webcam.grabFrame();
+    
     //  Sample hardware, update view frustum if needed, and send avatar data to mixer/agents
     updateAvatar(deltaTime);
 
@@ -2148,6 +2151,27 @@ void Application::displayOverlay() {
         drawtext(_glWidget->width() - 350, 50, 0.10, 0, 1.0, 0, paintMessage, 1, 1, 0);
     }
     
+    // render the webcam input frame
+    glEnable(GL_TEXTURE_2D);
+    glBindTexture(GL_TEXTURE_2D, _webcam.getFrameTextureID());
+    glBegin(GL_QUADS);
+        const int FRAME_PREVIEW_HEIGHT = 200;
+        int framePreviewWidth = _webcam.getFrameAspectRatio() * FRAME_PREVIEW_HEIGHT;
+        int bottom = _glWidget->height() - 400;
+        int left = _glWidget->width() - framePreviewWidth - 400;
+        
+        glTexCoord2f(0, 0);
+        glVertex2f(left, bottom);
+        glTexCoord2f(1, 0);
+        glVertex2f(left + framePreviewWidth, bottom);
+        glTexCoord2f(1, 1);
+        glVertex2f(left + framePreviewWidth, bottom + FRAME_PREVIEW_HEIGHT);
+        glTexCoord2f(0, 1);
+        glVertex2f(left, bottom + FRAME_PREVIEW_HEIGHT);
+    glEnd();
+    glBindTexture(GL_TEXTURE_2D, 0);
+    glDisable(GL_TEXTURE_2D);
+    
     glPopMatrix();
 }
 

interface/src/Webcam.cpp

@@ -14,7 +14,22 @@
 Webcam::Webcam() {
     if ((_capture = cvCaptureFromCAM(-1)) == 0) {
         printLog("Failed to open webcam.\n");
+        return;
     }
+    
+    // bump up the capture property
+    cvSetCaptureProperty(_capture, CV_CAP_PROP_FPS, 60);
+    
+    // get the dimensions of the frames
+    _frameWidth = cvGetCaptureProperty(_capture, CV_CAP_PROP_FRAME_WIDTH);
+    _frameHeight = cvGetCaptureProperty(_capture, CV_CAP_PROP_FRAME_HEIGHT);
+    
+    // initialize the texture that will contain the grabbed frames
+    glGenTextures(1, &_frameTextureID);
+    glBindTexture(GL_TEXTURE_2D, _frameTextureID);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, _frameWidth, _frameHeight, 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glBindTexture(GL_TEXTURE_2D, 0);
 }
 
 Webcam::~Webcam() {
@@ -22,3 +37,13 @@ Webcam::~Webcam() {
         cvReleaseCapture(&_capture);
     }
 }
+
+void Webcam::grabFrame() {
+    IplImage* image = cvQueryFrame(_capture);
+    if (image == 0) {
+        return;
+    }
+    glBindTexture(GL_TEXTURE_2D, _frameTextureID);
+    glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, _frameWidth, _frameHeight, GL_RGB, GL_UNSIGNED_BYTE, image->imageData);
+    glBindTexture(GL_TEXTURE_2D, 0);
+}

interface/src/Webcam.h

@@ -9,7 +9,9 @@
 #ifndef __interface__Webcam__
 #define __interface__Webcam__
 
-class CvCapture;
+#include "InterfaceConfig.h"
+
+struct CvCapture;
 
 class Webcam {
 public:
@@ -17,9 +19,20 @@ public:
     Webcam();
     ~Webcam();
 
+    int getFrameWidth() const { return _frameWidth; }
+    int getFrameHeight() const { return _frameHeight; }
+    float getFrameAspectRatio() const { return _frameWidth / (float)_frameHeight; }
+    GLuint getFrameTextureID() const { return _frameTextureID; }
+
+    void grabFrame();
+
 private:
     
     CvCapture* _capture;
+    
+    int _frameWidth;
+    int _frameHeight;
+    GLuint _frameTextureID;
 };
 
 #endif /* defined(__interface__Webcam__) */