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diff --git a/html/en/capture_guide.html b/html/en/capture_guide.html new file mode 100644 index 0000000..b3f84c3 --- /dev/null +++ b/html/en/capture_guide.html @@ -0,0 +1,81 @@ +<!doctype HTML PUBLIC "-//IETF//DTD HTML//EN"> +<html> + +<head> +<meta http-equiv="Content-Language" content="en-us"> +<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> +<title>Capture Guide</title> +<link rel="stylesheet" type="text/css" href="../style.css"> +</head> + +<body bgcolor="#FFFFFF"> + +<h1>Capture Guide</h1> +<h3><a name="Using">Using</a></h3> + + <p>You can list the installed capture devices using: </p> + + <pre>int imVideoCaptureDeviceCount(void) +const char* imVideoCaptureDeviceDesc(int device)</pre> + + <p>If a device was removed or added in run time, you must update the list + calling:</p> + + <pre>int imVideoCaptureReloadDevices(void)</pre> + + <p>To handle devices you must create a <b>imVideoCapture</b> structure + using the function <b>imVideoCaptureCreate</b>. With this handle you can + manage any of the available devices, but only one device. The handle must be + destroyed with <b>imVideoCaptureDestroy</b>.</p> + <p>If you want to access two or more devices at the same time you must create + two different structures, but be aware that this usually work for high quality + devices like Firewire and USB 2.0. Webcams that use USB1.x can be used if + connected to different USB 2.0 controllers.</p> + <p>The next thing is to connect to a specific device, because all the other + remaining functions depends on this connection. Just call <b>imVideoCaptureConnect</b> with one of the available capture device numbers.</p> + <p>You control when a device start processing frames using <b>imVideoCaptureLive</b>. Once live the frames can be captured using + <b>imVideoCaptureFrame</b>. Or you can use <b>imVideoCaptureOneFrame</b>, + it will start capturing, returns the captured frame and stop capturing.</p> + <p>But before capturing a frame you may want to configure the device. You can + do it using Attributes, or at least in Windows you can do it using the + configuration dialogs with a call to <b>imVideoCaptureShowDialog</b>.</p> + <p>A very simple sequence of operations to capture just one frame from the + first device available:</p> + + <pre>imVideoCapture* vc = imVideoCaptureCreate(); +if (!imVideoCaptureConnect(vc, 0)) + return; + +int width, height; +imVideoCaptureGetImageSize(vc, &width, &height); + +// initializes the data pointer +void* data = malloc(width*height*3); + +imVideoCaptureOneFrame(vc, data, IM_RGB); +imVideoCaptureDestroy(vc);</pre> + + <p>The capture library is completely independent from the other libraries. It + just uses the same description of the data buffer used in <b>imFileReadImageData</b>.</p> + +<h3><a name="Building">Building</a></h3> + + <p>You should include the <im_capture.h> header and link with the + "im_capture.lib" library. This library is independent of all IM libraries.</p> + <p>To link with the capture library in Windows using Visual C you will need + the file "<a href="../download/strmiids.zip">strmiids.lib</a>". To link it + using Dev-C++ or Mingw 3 you will need the "<b>im_capture.dll</b>".</p> + <p>To compile the capture source code you will need the Direct X 9 SDK. Notice + that since Direct X uses COM, CoInitialize(NULL) is called when the devices + are enumerated.</p> + <p>For more information on Direct X capture, i.e. Direct Show see:</p> + + <p> + <a href="http://msdn.microsoft.com/library/en-us/directx9_c/directX/htm/directshow.asp"> + http://msdn.microsoft.com/library/en-us/directx9_c/directX/htm/directshow.asp</a></p> + + + +</body> + +</html> |