Is ISampleGrabberCB::BufferCB is called only on Motion Detection?

DirectShow Development

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    - Passing parameters into the workflow. But the example is for console app... When you host it in winapp, it seems to be significantly more complicated. And how do I get the parameters from my custom action Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - Bind to an activity's Property Dialog Box I am new to WF but learning quick. A basic problem I am having is that when I am trying to expand the workflowProperties element in the Bind activity's property box to select workflowProperties.Item.ParentList.ParentWeb.AssociatedOwnerGroup.Users the window simply closes. There is no error and nothing is actually bound. I have searched to find someone with a similar problem but had no luck. To try and put it in more clearer terms. When I try to expand the workflowProperties list item in the bind activity's property box the window closes. It does this for other items as well (but not all). My workflow is in the very beginning stages and there is very little code. I find it weird that some of the items in the list are black and some are blue. Is this suppose to give some indication I am running Visual Studio 2005 with all the necessary WF addons. It doesn't matter if I am coding in C# or VB it happens either way. Thanks for the help! -------------- Edit -------------- I also get this error occasionally: 'Could not load file or assembly 'Microsoft.Sharepoint.Library', version = 12.0.0.0, culture = neutral, PublicKeyToken=[bunch of letters and numbers]' or one of its dependencies. The system could not find the file specified.' I am not sure what this is referring to since I believe i have all the necessary references set. Is there a file Microsoft.SharePoint.Library.dll that I am missing Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - The method to keep track of control changes with "IControlChangeNotify::OnNotify"? The following codes run very well: http://blogs.msdn.com/larryosterman/archive/2007/03/22/fun-with-the-endpoint-volume-interfaces-closing-the-loop.aspx Unfortunately,I use the interface "IAudioVolumeLevel ",I do as fllowing: #include "Strsafe.h" #include <mmdeviceapi.h> #include <endpointvolume.h> class CVolumeNotification : public IControlChangeNotify { LONG m_RefCount; ~CVolumeNotification(void); public: CVolumeNotification(void): m_RefCount(1) { } STDMETHODIMP_(ULONG)AddRef() { return InterlockedIncrement(&m_RefCount); } STDMETHODIMP_(ULONG)Release() { LONG ref = InterlockedDecrement(&m_RefCount); if (ref == 0) delete this; return ref; } STDMETHODIMP QueryInterface(REFIID IID, void **ReturnValue) { if (IID == IID_IUnknown || IID== __uuidof(IControlChangeNotify)) { *ReturnValue = static_cast<IUnknown*>(this); AddRef(); return S_OK; } *ReturnValue = NULL; return E_NOINTERFACE; } STDMETHODIMP OnNotify( DWORD dwSenderProcessId,LPCGUID pguidEventContext) { wchar_t outputString[ 256 ]; DWORD written; COORD writeCoord; StringCbPrintf(outputString, sizeof (outputString), L "Volume Changed: %f" , NotificationData->fMasterVolume); writeCoord.X = 0 ; writeCoord.Y = 3 ; WriteConsoleOutputCharacter(GetStdHandle(STD_OUTPUT_HANDLE), outputString, (DWORD)wcslen(outputString), writeCoord, &written); return S_OK; } And register it for notifications : CVolumeNotification *volumeNotification = new CVolumeNotification(); hr = pPartNext->RegisterControlChangeCallback(__uuidof(IAudioVolumeLevel),volumeNotification); When I get the notification ,the pguidEventContext in OnNotify is always NULL . How to get the pguidEventContext value Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - The flowed transaction could not be unmarshaled. Jesse, No firewall on any of the three. RPC I haven't checked yet. What exactly do I need to do Does DTCPing take RPC into account Also, since I posted the original message, I've been able to determine that the GUID under HKCR\CID for MSDTC is the same on both servers. Could that be causing this error I've seen some other posts indicating that them being the same can cause issues. Thanks! - Greg Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - TransactionScope & TSQL Transactions Florin Lazar - MSFT wrote: TransactionScope will pass the isolation level to SQL Server only as a suggestion. It depends on each database server implementation on what will happen in these type of situations (ignore the isolation level, try to follow it only when possible or return error when mismatched). Also see http://blogs.msdn.com/florinlazar/archive/2003/12/10/42686.aspx Cheers! Thanks for the reply, Florin. In my opinion, I think this is definitely a show-stopper. I would have hoped to mix transaction levels, especially for scenarios where multiple SPROCs are involved. For example, in .NET I could set my IsolationLevel to ReadCommitted, while in SQL Server I could set it to SERIALIZE for a SPROC that makes changes to the DB. To me that would increase the overall scalability, and at the same time maintain the integrity of the data in a limited manner. Anyway, I digress. Do you think we can hope for things to change in a future version of .NET Thanks again! Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - TTF Font Installation in Vista I'm having the same issue. I use an installer that is has an embedded manifest which says to run as an administrator, yet my fonts do not get installed in to the font directory. Any ideas Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - Event Queue operation failed with MessageQueueErrorCode QueueNotFound for queue Thanks ! Indigo Cowboy Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - Relying Party Certificate thumbprint not specified Hi Toland, Thanks for your answer. I've tried the above urls and none of them work, but to be honest I'm quite lost with all this stuff, I just used them following the example, but I don't know how I have to set them or where to configure them, and so on. Also I've done a text search in the entire solution looking for the fabrikam, contoso and adatum thumbprints but it didn't give any result. Finding the thumbprint of my intranetai certificate, I've only found it in one place in the whole solution, which is the "certificateThumbprint" setting in the app.config file in the STS project. I really don't know where I have to specify the relaying party certificate or what else I can do to solve it. Any help will be appreciated. Thanks, Ruben Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - Tutorials on WF and WPF Thank You Kavita. Are you speeking of "WpfHostingWfCallingWCF" or are there more in the SDK that i'm over looking them The "WpfHostingWfCallingWCF" solution fails when I try to tun it. The dialog says " Unable to start program 'C:\documents....\workflow.dll. do you have this problem also could you give me the link to the MSDN topic again please. thanks Mike Greenway Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - Closing osk.exe from other application osk.exe presumably has UIAccess=true, which is why you can't control it from a medium integrity process (as that would allow you to subvert the entire UIPI mechanism). I'm not sure this is a great design, what happens if a user already has the on screen keyboard enabled for their own accessibilty needs and your app shuts it down unexpectedly Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - list all active users in a domain - second try I've been searching on several forums about this topic and so far I didn't get any reasonable answer. I understand that a domain controller is an authenticator and not a server one logs into it. My question is: what is the most accurate way of getting the list of active users/hosts inside a domain If I enable auditing for account logon events on all domain controller servers, do I get logon and logoff events in an accurate manner. Does the logoff have a timeout, what happens if the pc goes away from the network and comes back again If I use some APIs like NetWkstaUserEnum, what is the impact on the network (assuming I do it remotely from one location for >1k PCs). Is WMI better then NetWkstaUserEnum How can I bind username to hostname/IP address for all active users (with a good accuracy) Regards, R. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - .NET Framework Configuration Tool No such luck on my side. It's in Administrative Tools in XP. Do you have to install the .NET Framework SDK on Vista in order to get it Vista comes with .NET 2.0 and .NET 3.0 which has the WPF components. If its there could you be a little more specific Thanks! Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - ping command in .bat is not working through IE7 in windows vista the .bat is located in intranet Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - Sound Problem Yeah I'm having the same problem too, I have a Creative Audigy 2 ZS Platinum, running Vista Home Premium (retail version), I think I have enough RAM (1.5GB), great CPU (Athlon 64 X2 4600+ Dual-Core), and eVGA GeForce 7900 GTO 512MB PCI-E graphics card. Everything was working fine under XP Pro, until I upgraded to Vista. I installed all the Vista drivers off from nVidia and Creative so it should be working fine but it isn't. I'm playing music on WMP and Winamp, or no matter what program. It will play for 30 secs or so, then it starts to lag (the whole system and the sound), then plays normal for a while, then does it again over and over. Is there a fix for this or anyone having the same problem Mines doesn't freeze up or restart to make it work again, it just does it over and over. Thanks in advance. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - How to transform a Byte[] object containing ink (ISF) to a Byte[] readable by Crystal Report with .NET 2.0? Well, Crystal report requires a datafield typed as Byte[] to report an image. I do use those Convert methods to pass back and forth the ink from the client to the server thru a hidden control. Everything works ok on that part. I am using crystal report to generate a printable version of the data collected on the web page. And that's when I have the problem. To generate the report I do this: I get the ink from a hidden control and write it as a string to an xml (xml contains other data - booleans and strings) that I pass to a web service to store into a blob field (image type) in the database. I retrieve the xml from another web service as a XmlNode and load it to a typed dataset (the ink is loaded in a System.Byte[] dataset column type). I use this typed dataset to build the report. At that point I can set the array back to an InkOverLay object to format it as a gif and write it to the disk. I can view the image even under paint. But crystal report does not support gif files neither. Do you want me to provide you all the pieces of code I am using Thank you for your help. Franki. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - FreeCoTaskMem (Memory Access Exception) in Vista, fine in XP .NET 2 Good thing Vista errors since it exposes bugs in your code. You're freeing the same memory more than once, that's probably the reason. The FreeCoTaskMem(pDib) call inside the try block is unecessary since you're calling it again in the finally block. It's also buggy since it doesn't zero out the pointer afterwards. The FreeCoTaskMem(bmpPtr) call shouldn't be there since bmpPtr doesn't point to a separately allocated buffer but to an offset inside the pDib buffer. And finally, IntPtr.Size returns the size in bytes, so it's either 4 or 8, never 32. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - Smart Card Application Initially, I suspected it might be the driver too. I managed to install the driver and could see the smart card reader listed on the Device Manager (PnP Manager). But when I ran the PC/SC app, SCardListsReaders() was empty with the return error code as 0x8010002E (No smart card readers are currently available). I suspected my driver could have failed linking to the Smart Card Resource Manager. (smclib.sys) Then, I plugged in a TDK-based reader with CCID support. The OS detected the reader as a CCID reader and installed the system supplied CCID driver. This CCID Driver (usbccid.sys) is provided by Microsoft. When I ran the PC/SC application, I had the same error too - 0x8010200E. I've checked on the Vista system, the Smart Card Service is started. So.. 1. Besides the Smart Card Service, are there any additional service we need to run 2. Do we need to recompile the PC/SC application for Vista - any new library / API function calls Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - How to get(set) cursor position in my service before logon? Hello, there. Our software is like the Stardock Multiplicity. If you have never seen it before, you can check what it is in this site. http://www.stardock.com/products/multiplicitypro/ To share keyboard/mouse even before user logon, cursor positioin check is needed. That's why I need getting/setting cursor position in service. Thanks again. Sweating Egg;; Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - about exception "Queue '......' ' is not enabled." Hi Pravin, I am very glad to get your help. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - Application won't elevate with manifest Embedded manifests are recommended. When developing; note that external manifest has to be picked up by the indexing service so that means just because you edit it, doesn't mean it's instantaneously picked up. You can kind of work around this by copying out of that directory and then placing it back into it, cause the indexer to pick it up. But you'd need to do this ever time you make a change to the manifest. Also, external manifests are rather insecure since they can be edited by anyone. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - InkCanvas selection adorner Stefan, Thanks for your answer. Do you happen to have anything that would get me started on (b) If I understand this correctly, I would need to create my own "selection" EditingMode (let's call it MySelectionEditingMode) that I will use in place of the default selection editing mode, like so: whenever selection behavior is needed, instead of setting InkCanvas.EditingMode = InkCanvasEditingMode.Select I would set InkCanvas.EditingMode = (InkCanvasEditingMode)MySelecti onEditingMode, where MySelectionEditingMode would be a constant with a value different from any found in the default InkCanvasEditingMode. [something tells me that's not going to work... ] Then I will probably need to override OnStylusDown, OnStylusUp, OnStylusMove (and similarly for mouse events) and take care of the rendering of the lasso, the logic behind figuring out what has been selected based on the lasso, and finally drawing the selection adorner and custom handling everything regarding selection move, resize, etc... and their respective visual feedbacks. I'm still not sure if this will work because if I then use the default implementation of InkCanvas.Select(...), wouldn't that mess things up Is my analysis correct or have I understood this wrong As I only have about 1 month experience with WPF (but enough experience with C# on .NET 2.0, and Tablet PC SDK), I guess I'm a little worried that going this deep in having to manually deal with lasso drawing and other such things might pose some challenges for me as I'm uncertain about what the best way to do this is in WPF. Thank you very much for your assistance. Regards, Boris Capitanu Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - How to record from 'Wave' or 'Stereo Mix' in Vista? What APIs did you use for this in XP They should continue to work on Vista. WASAPI has a special Loopback mode that allows a client to capture the post-mix audio stream, that may help as well. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - openthreadtoken fails on Windows Vista but not on Windows XP I am not logged in as an administrator. However, the CreateServer() function is invoked inside my port monitor. The port monitor is again invoked by the print spooler service. On Windows XP the service "SPOOLSV.EXE" is running as the user "SYSTEM". On Windows Vista the service "Spooler" is running as the "Local System" account. I tried to DuplicateHandle() of current thread as you suggested, see updated function. It works on Windows XP but on Windows Vista it still fails. However, now the error occurs a bit later, in the CreateProcessAsUser() function. GetLastError() returns 87 (ERROR_INVALID_PARAMETER) after calling CreateProcessAsUser(). I am trying to avoid the "session 0 isolation" issue on Windows Vista (not allowed to display any dialogs from a service which runs in session 0). In order to achieve that I have to create a process which runs as the current user (without knowing the username/password). The CreateProcessAsUser() function is invoked from a printer port monitor dll which is loaded by the print spooler service. Olav void CreateServer() { RPC_STATUS status; unsigned short *szStringBinding = NULL; TCHAR pszProtocolSequence[] = _T( "ncacn_np" ); TCHAR pszEndpoint[] = _T( \\pipe\\rpcserver ); status = RpcStringBindingCompose( NULL, reinterpret_cast < unsigned short *>(pszProtocolSequence), NULL, reinterpret_cast < unsigned short *>(pszEndpoint), NULL, &szStringBinding); // String binding output. if (status) { ::MessageBox(NULL,_T( "rpcstringbindingcompose feilet" ),_T( "debug" ),MB_OK); } status = RpcBindingFromStringBinding( szStringBinding, // The string binding to validate. &hRpc1Binding); // Put the result in the implicit binding handle defined in the IDL file. if (status) { ::MessageBox(NULL,_T( "rpcbindingfromstringbinding feilet" ),_T( "debug" ),MB_OK); } HANDLE hToken = NULL; HANDLE hTokenDup = NULL; LPVOID pEnvironment = NULL; STARTUPINFO si; PROCESS_INFORMATION pi; memset(&si, 0, sizeof (STARTUPINFO)); memset(&pi, 0, sizeof (PROCESS_INFORMATION)); si.cb = sizeof (STARTUPINFO); si.lpDesktop = _T( "Winsta0\\Default" ); HANDLE hThread = GetCurrentThread(); HANDLE hThreadDup = NULL; if (!DuplicateHandle(GetCurrentProcess(), hThread, GetCurrentProcess(), &hThreadDup, 0, FALSE, DUPLICATE_SAME_ACCESS)) { DWORD error = GetLastError(); TCHAR tmp[500]; wsprintf(tmp,_T( "duplicatehandle failed %d" ), error); ::MessageBox(NULL,tmp,_T( "debug" ),MB_OK); } if (!OpenThreadToken(hThreadDup, TOKEN_DUPLICATE, TRUE, &hToken)) { DWORD error = GetLastError(); TCHAR tmp[500]; wsprintf(tmp,_T( "openthreadtoken failed %d" ), error); ::MessageBox(NULL,tmp,_T( "debug" ),MB_OK); } CloseHandle(hThreadDup); if (!DuplicateTokenEx(hToken, TOKEN_IMPERSONATE|TOKEN_READ|TOKEN_ASSIGN_PRIMARY|TOKEN_DUPLICATE, NULL, SecurityImpersonation, TokenPrimary, &hTokenDup)) { ::MessageBox(NULL,_T( "duplicatetokenex failed" ),_T( "debug" ),MB_OK); } CloseHandle(hToken); if (!CreateEnvironmentBlock(&pEnvironment, hTokenDup, FALSE)) { ::MessageBox(NULL,_T( "createenvironment failed" ),_T( "debug" ),MB_OK); } // This function fails on Vista with error code 87, on Windows XP it is successfull if (!CreateProcessAsUser(hTokenDup, settings->GetRpcServer(), NULL, NULL, NULL, FALSE, CREATE_NO_WINDOW, pEnvironment, NULL, &si, &pi)) { DWORD error = GetLastError(); TCHAR tmp[500]; wsprintf(tmp,_T( "createprocessasuser failed %d" ), error); ::MessageBox(NULL,tmp,_T( "debug" ),MB_OK); } DestroyEnvironmentBlock(pEnvironment); CloseHandle(hTokenDup); } Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - RichTx32 merge module 2004. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - background windows flickers on top of fullscreen application in vista. It's using DirectX 9. I didn't develop the program but am looking for informations regarding what could cause the erratic behavior in vista. Please let me know if I have to get help somewhere else or need to get more info from the people who wrote the *drawing* part of the code. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - Please Help! Communication from App to Workflow and visa versa Hi, I face the same pb, but I want that my method who is called by CallExternalMethod raise an event for the upper layer, this would preserve the low coupling between layers, Here is my code : The method that is called by the CallExternalMethod activity which is part of ExternalDataExchange Implementation public void CalculationResult( int result) { if (ResultSubmited != null ) ResultSubmited( this , new ResultSubmitedEventArg (result)); } Here is the code that bind the event thrown me the external method public void Add( int a, int b) { _myServ = this .Services.Get< IWorkflowService >(); _WorkFlowId = _myServ.StartWorkflow( typeof (CABWorkflows. Workflow1 )); CalcExternalDataExchange ex = _myServ.GetExchangeService< CalcExternalDataExchange >(); ex.ResultSubmited += new EventHandler<ResultSubmitedEventArg>(ex_ResultSubmited); // this line make the exception to be thrown ex.RaiseSubmitCalculation(a, b, 3, _WorkFlowId); //Other event that work fine } But as soon has I bind the event in the upper layer it throw an Exception that say that my upper classes are not Serialisable How can I throw a custom event from the CallExternalMethode methode Thx Axel Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - WM ASF Writer memory leak? Hi all, I have tried to build a graph to capture images then save them into a WMV file. I used a SmartTee filter to preview the result and save it to file. I found that the virtual memory increase stably when I did the following steps; 1. Build graph, and connect the source fillter, SmartTee filter, Render filter, ASF writer. 2. Run the graph. 3. Stop the graph. 4. Remove all filters, then release the graph 5. go to step 1. If I implemented the steps without adding ASF writer, the virtual memory looked normal. My system has installed HotFix_839203 that fixs Windows Media Component memory leak. But it still happened. Does anyone meet such problem Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - VMR9Allocator in fullscreen Hi. Thank you for your answer. Well, in fact, TextureD3D9 was the first sample that I tried : it does not fulfill my particular needs, because my videos are very large, and so the frame rate is very low. I tried different samples and VMR9Allocator seemed to be the best one. Now that my frame rate is OK, and that I display exactly what I want, it remains the problem of tearing. I checked with a common directx application, that in windowed mode there is tearing and that in fullscreen (the windowed parameter of the D3DPRESENT_PARAMETERS is set to false) there is none. It seems that there is a VMR9 Renderless Fullscreen mode, but unfortunately I don't succeed in implementing this mode. As I told before, the simple way to explain my problem is : how to put the VMR9Allocator sample in fullscreen mode (not just a popup window with a maximized size). I go on searching. Any help is welcome. Thank you. Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista
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    - RegOpenKeyEx error that image not found I used RegOpenKeyEx to open Software\Microsoft\Windows\CurrentVersion\Uninstall, as below: long rc = RegOpenKeyEx(HKEY_LOCAL_MACHINE, REGSTR_PATH_UNINSTALL, 0, KEY_READ|KEY_WRITE, &hChildKey); I got an error on some machines, the error No. is 1813 ERROR_RESOURCE_TYPE_NOT_FOUND (The specified resource type cannot be found in the image file.) But it's no problem on the other machines, the registry entry is opened successfully. That's weird, the Operating system are the same, it's XP Pro. with sp2. Does anyone has any idea what's going on And any suggestion Thanks in advance! ~Vian Tag: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection? Software Development for Windows Vista

vlamak

Hi,

I am writing a small "Capture from WebCam" application and I have notices that if my webcam is facing some surface (w/o movement) the BufferCB is not called in my callback. Also, when I rapidly move it around, the BufferCB is called. Is this correct that BufferCB is called only if the frames are changing (like in Motion Detection)

Please give me more details.

Also, Is there a way to capture something from a script, if yes - please tell me the interfaces available to scripting lanuages. BTW, I have tried WIA, but it doesn't work on my machine (even the scanner and camera wizard) cannot capture anything.

Thank You,

Vlad.

Re: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection?

Thore Karlsen

No, you should get a callback for every frame that passes through the sample grabber. The other explanation is that your webcam only generates frames when there's motion, which sounds strange, but I guess it's possible. When there's no motion, does the frame look completely static Can you detect any movement in the noise or anything like that

Re: DirectShow Development Is ISampleGrabberCB::BufferCB is called only on Motion Detection?

vlamak

I don't know if the frame is static or not if there is no motion. The webcam is the cheapest Logitech QuickCam IM. My graph has 4 filters: Webcam(CAPTURE_PIN)<---->Sample Grabber<---->Null Renderer, and Webcam(STILL_PIN)<---->Null Renderer.

In my program I just print a msg within the Buffer CB, and it happens that this msg is printed if the frames are changing.

Thore Karlsen: I will replace the Null Renderer with the VMR and see what happens.