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<h2><a name=MYSAMPLE><span style='font-family:Verdana'>Testcap �</span></a><spanstyle='font-family:Verdana'> A WDM Streaming Video Capture Driver whichrequires no Hardware<o:p></o:p></span></h2>
<h3><span style='font-family:Verdana'>SUMMARY<o:p></o:p></span></h3>
<p><span style='font-size:10.0pt;font-family:Verdana'>Testcap is a prototypicalsample WDM stream class video capture driver which does not require anyhardware for operation. The driver simulates the front-end components of a PC/TV,including input selection, TvTuning, TvAudio control, and finally, digitalvideo streaming. <o:p></o:p></span></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>The TvTuner componentsupports tuning modes of Analog TV (NTSC/PAL/SECAM), AM/FM Radio, as well asATSC (American Broadcast Digital Television).<o:p></o:p></span></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>Testcap manifests itselfin a DirectShow graph as four separate filters:<o:p></o:p></span></p>
<ul type=disc> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l2 level1 lfo3;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>Testcap Capture <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l2 level1 lfo3;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>Testcap TvTuner <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l2 level1 lfo3;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>Testcap TVAudio <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l2 level1 lfo3;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>Testcap Crossbar<o:p></o:p></span></li></ul>
<p><span style='font-size:10.0pt;font-family:Verdana'>The capture portionproduces five output streams, two of which are Capture and Preview whichproduce a variety of colorbars and grayscale patterns depending on the videoinput selected on the crossbar. The capture and preview streams contain videosamples in either RGB24 or YUV422 color spaces and offer a large number ofdifferent image dimensions.<span style="mso-spacerun: yes">� </span>The otherthree capture streams are VBI, HWCC, and HWNABTS.<span style="mso-spacerun:yes">� </span>These three are VBI streams, and offer simulated CC and NABTSwaveforms for decoding, and simulated hardware decoded CC and NABTS.<o:p></o:p></span></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>This driver containssample implementations for almost all of the property sets involved in WDMvideo capture. Since Testcap doesn't control actual hardware, most of theproperty set implementations are useful only as prototypes which you can borrowfor your own implementations. This driver represents one extreme of combiningall functionality representing the front end of a PC/TV into a single driver.The other extreme is to create a separate driver each element: TvTuner,TvAudio, Crossbar, and Capture. <o:p></o:p></span></p>
<p><b><span style='font-size:10.0pt;font-family:Verdana'>Keywords</span></b><spanstyle='font-size:10.0pt;font-family:Verdana'>: Video capture, WDM, streamclass, TvTuner, driver, VBI.<o:p></o:p></span></p>
<h3><span style='font-family:Verdana'>BUILDING THE SAMPLE<o:p></o:p></span></h3>
<p><! ---------------- Snip Snip ---------------- ><span style='font-size:10.0pt;font-family:Verdana'>The sample is built with the standard DDK BUILD utility inthe standard checked or free DDK build environment. Testcap is completelycontained in one directory. The resulting binary from the build process isTestcap.sys, which is compatible on x86 and Alpha platforms.<o:p></o:p></span></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>Testcap is not a PnPdriver, since no hardware is involved, and it must be installed manually:<o:p></o:p></span></p>
<ul type=disc> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo6;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>My Computer.Properties.Hardware.Hardware Wizard.Add new hardware. <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo6;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>"To install hardware which is not Plug and Play compatible, click Next." <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo6;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>"No, I want to select the hardware from a list." <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo6;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>"What type of hardware do you want to install" <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo6;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>Sound, Video, and Game Controllers <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo6;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>"Have Disk�" <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo6;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>Browse to find "Testcap.inf" <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo6;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>Browse to find "Testcap.sys" when requested<o:p></o:p></span></li></ul>
<h3><span style='font-family:Verdana'><! ---------------- Snip Snip ---------------- >RESOURCES<o:p></o:p></span></h3>
<p><span style='font-size:10.0pt;font-family:Verdana'>This driver has beentested with the following applicatons: Graphedt.exe, AMCap.exe, WebTV forWindows.<o:p></o:p></span></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>This website containsgeneral information on driver and hardware development:<o:p></o:p></span></p>
<p style='margin-left:1.0in'><a href="http://www.microsoft.com/hwdev">http://www.microsoft.com/hwdev</a><spanstyle='font-size:10.0pt;font-family:Verdana'> <o:p></o:p></span></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>This website contains informationon DirectShow:<o:p></o:p></span></p>
<p style='margin-left:1.0in'><a href="http://www.microsoft.com/directx">http://www.microsoft.com/directx</a></p>
<h3 style='margin-left:1.0in'><span style='font-family:Verdana'> <o:p></o:p></span></h3>
<h3><span style='font-family:Verdana'>CODE TOUR<o:p></o:p></span></h3>
<h4><span style='font-family:Verdana'>File Manifest<o:p></o:p></span></h4>
<table border=0 cellspacing=0 cellpadding=0 width="100%" style='width:100.0%; border-collapse:collapse;mso-padding-alt:0in 5.4pt 0in 5.4pt'> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><b><u>File<o:p></o:p></u></b></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><b><u>Description<o:p></o:p></u></b></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre>Testcap.htm</pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre>The Sample Tour documentation for this sample (this file).</pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>SOURCES<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>The generic file for building the code sample.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Testcap.inf<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>A sample installation file.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapStrm.h<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Declarations of streams and formats supported by the driver.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapMain.c<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>DriverEntry(), initialize, un-initialize, and adapter SRB processing.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapMain.h<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Header file for above.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapVideo.c<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Stream SRB processing.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapVideo.h<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Header file for above.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapXfer.c<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Synthesizes images.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapXfer.h<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Header file for above.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapIRQ.c<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Sample IRQ routines. <o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapProp.c<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Process all adapter property sets including TvTuner, Crossbar, VideoProcAmp, and CameraControl properties.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapProp.h<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Header file for above.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapVBI.c<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Stream SRB processing for VBI pins<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>CapVBI.h<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Header file for above.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>DDraw.c<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Sample functions for handling kernel DDraw interfaces.<span style="mso-spacerun: yes">� </span>Not actually used by this driver at present.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Mediums.h<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Describes topological connections for the streams.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Testcap.rc<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Resource file mainly for version<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>VBIdata.c<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Contains typical VBI waveforms.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>VBIdata.h<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Header file for above.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>VBIXfer.c<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Synthesizes VBI data.<o:p></o:p></span></pre></td> </tr> <tr> <td valign=top style='padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>VBIXfer.h<o:p></o:p></span></pre></td> <td width="85%" valign=top style='width:85.0%;padding:0in 5.4pt 0in 5.4pt'><pre><span style='font-family:Courier'>Header file for above.<o:p></o:p></span></pre></td> </tr></table>
<pre><span style='font-family:Verdana'><span style="mso-spacerun: yes">�</span><o:p></o:p></span></pre>
<h4>Programming Tour</h4>
<p><span style='font-size:10.0pt;font-family:Verdana'>DriverEntry() is theinitial point of entry for the driver. It initializes the hardware initializationstructure and registers the secondary entry point functions. <o:p></o:p></span></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>HwReceivePacket fielddescribes the entry point for receiving SRBs (Stream Request Packet) fromstream class driver. Here is a possible sequence of SRBs that this driver mayreceive.<o:p></o:p></span></p>
<ol start=1 type=1> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l1 level1 lfo9;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>SRB_INITIALIZE_DEVICE to initialize the device, and called after DriverEntry().<o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l1 level1 lfo9;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>SRB_GET_STREAM_INFO to get supported stream format.<o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l1 level1 lfo9;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>SRB_GET_DATA_INTERSECTION to query a supported format given some key fields.<o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l1 level1 lfo9;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>SRB_OPEN_STREAM to open a stream with supply format from SRB_GET_DATA_INTERSECTION. Two additional entry point functions are register for this stream for controlling the streaming state (Srb->StreamObject->ReceiveControlPacket) and for streaming data (Srb->StreamObject->ReceiveDataPacket). <o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l1 level1 lfo9;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>SRB_CLOSE_STREAM to close the open stream.<o:p></o:p></span></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l1 level1 lfo9;tab-stops:list .5in'><span style='font-size:10.0pt; font-family:Verdana'>SRB_UNINITIALIZE_DEVICE to indicate that a device has been unloaded or removed.<o:p></o:p></span></li></ol>
<p><span style='font-size:10.0pt;font-family:Verdana'>This driver also registerentry points for canceling packets (HwCancelPacket) and for notifying if apacket has timeout (HwRequestTimeoutHandler). <o:p></o:p></span></p>
<p><b><span style='font-size:10.0pt;font-family:Verdana'>Clocks<o:p></o:p></span></b></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>Testcap, like most videocapture drivers, does not act as clock source for a filter graph. <o:p></o:p></span></p>
<p><b><span style='font-size:10.0pt;font-family:Verdana'>Frame rate and droppedframes<o:p></o:p></span></b></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>Digital cameras supportdiscrete frame rates; however, a client application can request to stream at anyrate. It is required by WDM video capture driver to either match or select thenext lower frame rate available. Over sampling can cause synchronizationproblems. <o:p></o:p></span></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>The dropped frameinformation is calculated instead of actual count, and it is based on thecapture rate and the actual counts of frames captured. <o:p></o:p></span></p>
<p><b><span style='font-size:10.0pt;font-family:Verdana'>Work items<o:p></o:p></span></b></p>
<p><span style='font-size:10.0pt;font-family:Verdana'>Testcap is not persistingTvTuner, Crossbar, VideoProcAmp and CameraControl property settings betweenreboots. For an example of how this should be handled, look at the 1394 digitalvideo conferencing camera driver (1394dcam, capprop.c), also in this DDK.<o:p></o:p></span></p>
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<p><span style='font-size:7.5pt;font-family:"MS Sans Serif"'>� 1998 MicrosoftCorporation</span><span style='font-size:10.0pt;font-family:Verdana'> <o:p></o:p></span></p>
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