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|
#include <opencv/cv.h>
#include <opencv/highgui.h>
#include <stdio.h>
// Create a string
using namespace std;
// Image to capture the frame from video
IplImage* image = NULL; // original image
IplImage* lastImage = NULL; // last image
IplImage* diffImage = NULL; // differences between images
IplImage* threshImage = NULL; // threshold image
IplImage* mjpegImage = NULL;
// Function protoype for characteristics about a video
void showCaptureProperties(CvCapture* capture)
{
// Read the video's frame size out of the avi
int width, height, framePerSecond;
width = (int)cvGetCaptureProperty(capture,CV_CAP_PROP_FRAME_WIDTH);
height = (int)cvGetCaptureProperty(capture,CV_CAP_PROP_FRAME_HEIGHT);
framePerSecond = (int)cvGetCaptureProperty(capture,CV_CAP_PROP_FPS);
printf("Video properties ( width*height - frame per seconde ): %d*%d - %d\n", width, height, framePerSecond);
}
// Main function, defines the entry point for the program
int main(int argc, char** argv)
{
// Structure for getting video from avi
CvCapture* capture = 0;
// Image to capture the frame from video
IplImage* frame = NULL;
// Check for the correct usage of the command line
if(argc > 1)
capture = cvCaptureFromAVI(argv[1]);
if(!capture)
{
fprintf(stderr,"Could not initialize capturing...\n");
return -1;
}
// The Linux version of OpenCV has a bug. You need to read a frame before an AVI's properties can be queried.
cvQueryFrame(capture);
// Read the video's frame size out of the avi
if(cvSetCaptureProperty(capture, CV_CAP_PROP_FRAME_WIDTH,320))
printf("Cant set width property\n");
if(cvSetCaptureProperty(capture, CV_CAP_PROP_FRAME_HEIGHT, 240))
printf("Cant set height property\n");
// Threshold value
int thresh = 40;
// Create window object (use flag=0 to allow resize, 1 to auto fix size)
cvNamedWindow("Live video display", 1);
cvNamedWindow("Difference between subsequence image frames",1);
cvNamedWindow("Difference between subsequence image frames with threshold", 1);
cvCreateTrackbar("Threshold", "Difference between subsequence image frames with threshold", &thresh, 255, NULL);
// Call the function showCaptureProperties
showCaptureProperties(capture);
char key; // user input
int EVENT_LOOP_DELAY = 40; // delay for GUI window
// 40 ms equates to 1000ms/25fps = 40ms per frame
int numberScenes = 1;
int idScene = 0;
int framePerSecond;
char filename[256];
CvVideoWriter* writer = NULL;
int frameId = 0;
if (argc > 2)
thresh = atoi(argv[2]);
printf(">>>> scene detection : %s\n",argv[1]);
for(;;)
{
// Capture the frame and load it in IplImage
frame = cvQueryFrame(capture);
if(!frame)
break;
frameId++;
// Create image header same as frame but with 1 channel to gray
if(!image)
{
image = cvCreateImage(cvSize(frame->width, frame->height), frame->depth,1);
image->origin = frame->origin;
threshImage = cvCreateImage(cvSize(frame->width, frame->height), frame->depth,1);
threshImage->origin = frame->origin;
}
// Convert frame to gray and store in image
cvCvtColor(frame, image, CV_BGR2GRAY);
// Create lastImage clone actual image
if(!lastImage)
{
lastImage = cvCloneImage(image);
}
// Create image header same as frame but with 1 channel to gray
if(!diffImage)
{
diffImage = cvCreateImage(cvSize(frame->width, frame->height), frame->depth,1);
diffImage->origin = frame->origin;
}
// Display movie in window
cvShowImage("Live video display", frame);
// Differences with actual and last image
cvAbsDiff(image, lastImage, diffImage);
cvShowImage("Difference between subsequence image frames", diffImage);
//Threshold image
cvThreshold(diffImage, threshImage, thresh, 255, CV_THRESH_BINARY);
cvShowImage("Difference between subsequence image frames with threshold", threshImage);
// Percentage of white pixels on the image
int counterWhitePixels = 0;
int percentageWhitePixels = 0;
int numberPixels = threshImage->width*threshImage->height;
for(int i=0; i<threshImage->width; i++)
{
for(int j=0; j<threshImage->height; j++)
{
CvScalar pixel = cvGet2D(threshImage, j, i);
if(pixel.val[0] == 255)
counterWhitePixels++;
}
}
percentageWhitePixels = counterWhitePixels * 100 / numberPixels;
// detect movie scenes
if (percentageWhitePixels > thresh)
{
numberScenes++;
cvReleaseVideoWriter(&writer);
}
// Split movie into scenes
framePerSecond = (int)cvGetCaptureProperty(capture,CV_CAP_PROP_FPS);
CvSize size = cvSize((int)cvGetCaptureProperty(capture,CV_CAP_PROP_FRAME_WIDTH),
(int)cvGetCaptureProperty(capture,CV_CAP_PROP_FRAME_HEIGHT));
if (idScene != numberScenes)
{
idScene = numberScenes;
printf("Shot detected #%d at frame #%d\n",idScene,frameId);
sprintf(filename,"shot-%d.avi",idScene);
writer = cvCreateVideoWriter(filename, CV_FOURCC('M','J','P','G'), framePerSecond, size);
//writer = cvCreateVideoWriter(filename, -1, 25, cvSize(320,240));
printf("--- seq #%d frame id #%d threshold = %d \n",idScene,frameId,percentageWhitePixels);
printf("w=%d,h=%d\n",frame->width,frame->height);
mjpegImage = cvCreateImage(size, IPL_DEPTH_8U, 3);
//mjpegImage = cvCloneImage(frame);
cvWriteFrame(writer, frame);
}
// Change datas
lastImage = cvCloneImage(image);
// Start event processing loop (very important,in fact essential for GUI)
// 40 ms roughly equates to 1000ms/25fps = 4ms per frame
key = cvWaitKey(EVENT_LOOP_DELAY);
if (key == 'x')
{
// If user presses "x" then exit
printf("Keyboard exit requested : exiting now - bye!\n");
break;
}
}
printf("<<<< scene detection : %s\n",argv[1]);
// Destroy capture object
cvReleaseVideoWriter(&writer);
// Destroy capture object
cvReleaseCapture(&capture);
// Destroys images created
cvReleaseImage(&frame);
cvReleaseImage(&image);
cvReleaseImage(&lastImage);
cvReleaseImage(&threshImage);
cvReleaseImage(&diffImage);
cvReleaseImage(&mjpegImage);
// Destroy window objects
cvDestroyAllWindows();
// All OK : main returns 0
return 0;
} |
