Delphi-OpenCV/2.4.3/samples/OpenCV_Tuturials/OpenCV_2_LoadVideo.dpr

62 lines
2.2 KiB
ObjectPascal
Raw Normal View History

{$APPTYPE CONSOLE}
program OpenCV_2_LoadVideo;
uses
core_c in '..\..\include\сore\core_c.pas',
core.types_c in '..\..\include\сore\core.types_c.pas',
highgui_c in '..\..\include\highgui\highgui_c.pas';
const
// declare video filename
VIDEO_FILE_NAME = '768x576.avi';
// declare escape char
ESCAPE_CHAR = 27;
var
// declate an opencv video file capture object, users can use this object to
// interact with the video file, get/set properties and also grab video frames
capture: pCVCapture;
// declare an opencv image pointer variable
frame: pIplImage;
// declate a key variable to get user key pressed
key: integer;
begin
// create capture object for specific video filename
capture := cvCreateFileCapture(VIDEO_FILE_NAME);
// check if capture assigned, if not then it means that opencv can not open
// the requested file, opencv uses VFW to open the files so some file formats
// are not fully supported (can be enhence with FFMPEG support but this is
// beyond our scope right now
if Assigned(capture) then
begin
// create display window
cvNamedWindow('video');
// reset user key pressed
key := 0;
// loop while user didn't press ESCAPE
while key <> ESCAPE_CHAR do
begin
// start grabbing frames, single frame at a time, this method is a
// combination of two methods one grab frame and the other advances to the
// next frame
//
// REMARK: do not (!!!) release "frame" object since it is used internally
// by the capture object is its memory is release when the "capture" object
// is being destroyed
frame := cvQueryFrame(capture);
// check if frame is valid, when you reach end-of-file "frame" object
// starts to be NIL (since the method advances to the next frame each time
// is is called...)
if Assigned(frame) then
// show frame in window
cvShowImage('video', frame);
// wait for user key, delay is in msec so 1000msec = 1sec wait period
key := cvWaitKey(1000);
end;
// destroy display windows
cvDestroyAllWindows;
// release "capture" object and its related memory
cvReleaseCapture(capture);
end;
end.