OpenCV Learning Note 2: Turn on the camera and handle the captured image __opencv

It was a bit too gradual, a waste of time, and later code annotations as much as possible in the comments, concise and clear. Open Camera

#include "cv.h"//OPENCV core function library #include "highgui.h"//gui function library//Main method (note the formal parameter list under vs) int main (int argc, char** argv) {/
    /Create window (window name, Window property flag)//int Cvnamedwindow (const char* name, int flags=cv_window_autosize);

    Cvnamedwindow ("Win"); Cvcapture structure, which is used to hold the image capture information//cvcreatecameracapture (int index); Initialize the video from the camera and only one camera when the index number takes 0 cvcapture* capture = CVCR

    Eatecameracapture (0);

    Iplimage is a structural body iplimage* frame which represents an image;

        while (1) {//cvqueryframe crawls a frame from a camera or file in a dead loop, and then extracts and returns the frame = Cvqueryframe (capture);  Fetch failure when the return value is NULL//failure is often due to the camera index number is not correct or just initialized in the grab frame (camera boot need time) if (null==frame) break;

        Cvshowimage ("Win", frame);
        When the delay is less than or equal to 0, if there is no keyboard trigger, wait until the return value is-1//Otherwise the return value is the keyboard-pressed code//when delay is greater than 0 o'clock, if there is no trigger for the keyboard, wait delay milliseconds, the return value is-1 Otherwise the return value is the keyboard-pressed code character//int Cvwaitkey (inT delay=0);

        char C = cvwaitkey (50);
    If the return value is (ESC's ASCII) if (c =) break;//exits the loop}//cvreleasecapture: Frees up the memory space that the cvcapture structure creates

    Cvreleasecapture (&capture);

    Cvdestroywindow: Destroys a window with a specified name Cvdestroywindow ("Win");
return 0; }

Artwork-> grayscale-> two value

#include "cv.h" #include "highgui.h" int main (int argc, char** argv) {//Create window (window name, Window property flag) Cvnamedwindow ("captured artwork")
    ;
    Cvnamedwindow ("After the turn of gray-scale map");

    Cvnamedwindow ("second-valued");
    Cvcapture structure, which is used to hold the information of image capture cvcapture* capture = cvcreatecameracapture (0);

    Iplimage is a structural body iplimage* frame which represents an image;
        while (true) {/**----camera-> The original image----**///crawl and return a frame = Cvqueryframe (capture);

        Crawl failure if (null==frame) break;
        /**----Grayscale and two-valued map space opening----**///Create image allocation storage space (image size, image depth, channel number);
        iplimage* Cvcreateimage (cvsize cvsize (int width, int height), int depth, int channels);
        Here ipl_depth_8u is a 8-bit unsigned integer iplimage *dst_grey = Cvcreateimage (Cvgetsize (frame), ipl_depth_8u, 1);

        Iplimage *dst_binary = Cvcreateimage (Cvgetsize (frame), ipl_depth_8u, 1);
        /**----Original-> grayscale map----**///Color space conversion (input image, output image, conversion code);
        void Cvcvtcolor (const cvarr* SRC, cvarr* dst, int code); Here CV_bgr2gray is from RGB to grayscale Cvcvtcolor (frame, Dst_grey, Cv_bgr2gray);
        /**----Grayscale-> Two value----**///fixed threshold operation for single channel array (input image, output image, threshold, maximum value, threshold type);
        void Cvthreshold (const cvarr* SRC, cvarr* DST, double threshold, double max_value, int threshold_type);

        Here Cv_thresh_otsu the function uses the OTSU law to look for thresholds, no longer using their own threshold values Cvthreshold (Dst_grey, dst_binary,, 255, Cv_thresh_otsu);
        /**----Display the image in the specified window----**/cvshowimage ("captured artwork", frame);
        Cvshowimage ("After the gray-scale map", Dst_grey);

        Cvshowimage ("second-valued", dst_binary);
        50ms or with key char C = Cvwaitkey (50);
            Exit if (c = = 27) {//Free space Cvreleaseimage (&dst_binary) when pressing ESC;
            Cvreleaseimage (&dst_grey);
        Break
    }//Free space cvreleaseimage (&frame);
    Cvreleasecapture (&capture);
    Destroy All Windows Cvdestroyallwindows ();
return 0; }