server/image.c

   1 #include "cv.h"
   2 #include "highgui_c.h"
   3 #include "image.h"
   4 #include <string.h>
   5 #include <stdio.h>
   6 #include <pthread.h>
   7
   8 static CvCapture * g_capture = NULL;
   9 static int g_captureID = -1;
  10
  11 void Image_Handler(FCGIContext * context, char * params)
  12 {
  13
  14         int num = 0, width = 1600, height = 1200;       // Set Default values
  15         FCGIValue val[] = {
  16                 {"num", &num, FCGI_INT_T},
  17                 {"width", &width, FCGI_INT_T},
  18                 {"height", &height, FCGI_INT_T}
  19         };
  20         if (!FCGI_ParseRequest(context, params, val, 3))        // Populate val
  21                 return;
  22         // Ensure the camera id is 0 or 1. Even though we plan to only have 1 camera attached at a time, this will allow 2. increase
  23         else if (num < 0 || num > 1) {
  24                 FCGI_RejectJSON(context, "Invalid capture number");
  25                 return;
  26         // Ensure valid widths
  27         } else if (width <= 0 || height <= 0) {
  28                 FCGI_RejectJSON(context, "Invalid width/height");
  29                 return;
  30         }
  31
  32         IplImage * src = NULL;   // Source Image
  33         CvMat * encoded = NULL;         // Encoded Image
  34
  35         Camera_GetImage( num, width, height ,&src);
  36
  37         Log(LOGDEBUG, "About to encode");
  38         encoded = cvEncodeImage(".jpg",src,0);
  39         Log(LOGDEBUG, "Encoded");
  40
  41         Log(LOGNOTE, "Sending image!");
  42         FCGI_PrintRaw("Content-type: image/jpg\r\n");
  43         FCGI_PrintRaw("Cache-Control: no-cache, no-store, must-revalidate\r\n\r\n");
  44         //FCGI_PrintRaw("Content-Length: %d", g_encoded->rows*g_encoded->cols);
  45         FCGI_WriteBinary(encoded->data.ptr,1,encoded->rows*encoded->cols);
  46
  47         cvReleaseMat(&encoded);
  48         cvReleaseImageHeader(&src);
  49 }
  50
  51 /**
  52  * Attempts to get an image from a camera
  53  * @param num - Camera id
  54  * @param width - Width to force
  55  * @param height - Height to force
  56  * @param image - Pointer to CvMat* to set with result
  57  * @returns true on success, false on error
  58  */
  59  bool Camera_GetImage(int num, int width, int height,  IplImage ** frame)
  60  {
  61         Log(LOGDEBUG, "Called with arguments num=%d width=%d height=%d frame=%p", num,width,height, frame);
  62         static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; // Need to use a mutex to ensure 2 captures are not open at once
  63         pthread_mutex_lock(&mutex);
  64         bool result = false;
  65
  66         if( g_capture == NULL)
  67         {
  68                 g_capture = cvCreateCameraCapture(num);
  69                 g_captureID = num;
  70         }
  71         else if( num != g_captureID)
  72         {
  73                 cvReleaseCapture(&g_capture);
  74                 g_capture = cvCreateCameraCapture(num);
  75                 g_captureID = num;
  76         }
  77
  78         if (g_capture != NULL)
  79         {
  80
  81                 cvSetCaptureProperty(g_capture, CV_CAP_PROP_FRAME_WIDTH, width);
  82                 cvSetCaptureProperty(g_capture, CV_CAP_PROP_FRAME_HEIGHT, height);
  83
  84                 *frame = cvQueryFrame(g_capture);
  85                 result = (*frame != NULL);
  86
  87         //cvShowImage("display", *image);
  88         //cvWaitKey(0);
  89         //cvSaveImage("test.jpg",*image,0);
  90
  91                 Log(LOGDEBUG, "At end of mutex");
  92         }
  93
  94         pthread_mutex_unlock(&mutex);   //Close the mutex
  95
  96         //NOTE: Never have a "return" statement before the mutex is unlocked; it causes deadlocks!
  97         return result;
  98 }
  99
 100 void Image_Cleanup()
 101 {
 102         // Release the capture and IplImage pointers
 103         //cvReleaseImageHeader(&g_frame);
 104         cvReleaseCapture(&g_capture);
 105 }
 106