C / C++ / MFC

22-May-07 0:45

I succeded in fastforwarding the .wmv file in direct show but still
could not play rewind .

RajeshGupta

Mark Salsbery22-May-07 3:53

Mark Salsbery

22-May-07 3:53

Do you mean play in reverse or position to an earlier time?

Some filters aren't capable of playing in reverse. Check the capabilities of the streams.

Mark

"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder

rjkg22-May-07 18:36

22-May-07 18:36

I mean to play in reverse i check
DWORD dwCaps = AM_SEEKING_CanSeekAbsolute | AM_SEEKING_CanSeekForwards | AM_SEEKING_CanSeekBackwards |AM_SEEKING_CanPlayBackwards;

HRESULT hr=g_pSeek->CheckCapabilities(&dwCaps);
is true . but still when i write code
g_pSeek->SetRate(-1.0);
graph could not play in reverse .

RajeshGupta

Mark Salsbery23-May-07 5:22

Mark Salsbery

23-May-07 5:22

CheckCapabilities() returns true? That's not a proper capabilities check - actually if all the
capabilities you check for are available, it should return S_OK, which would be FALSE.
Regardless, the method returns an HRESULT, not a bool.

You should check something like this:

DWORD dwCaps = AM_SEEKING_CanSeekAbsolute | AM_SEEKING_CanSeekForwards  
                      | AM_SEEKING_CanSeekBackwards | AM_SEEKING_CanPlayBackwards;
 
HRESULT hr=g_pSeek->CheckCapabilities(&dwCaps);
if (hr != S_OK)
{
   // Not all the capabilities were present
 
   if (dwCaps & AM_SEEKING_CanPlayBackwards)
   {
      // can play backwards
   }
   else
   {
      // can NOT play backwards
   }
}

"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder

rjkg24-May-07 1:14

24-May-07 1:14

I am getting in step

if (dwCaps & AM_SEEKING_CanPlayBackwards)
{ // can play backwards }

can playback . but when i set rate
g_pSeek->SetRate(-1.0);

but is not playing in backbard . it just stop.
can you suggest me more refinement

RajeshGupta

Mark Salsbery24-May-07 4:56

Mark Salsbery

24-May-07 4:56

What is the return value from g_pSeek->SetRate(-1.0); ?

"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder

rjkg24-May-07 19:31

rewind the wmv file in direct show

24-May-07 19:31

the return value is 0. send me peace of code so that I can understand
clearly

RajeshGupta

rjkg29-May-07 0:02

29-May-07 0:02

Hi I am in great trouble and still could not find the answer how to
rewind the wmv file.

RajeshGupta

rjkg29-May-07 1:35

29-May-07 1:35

still I could not able to rewind the file . can any one give me more help
that is explaned above with the help of some piece of source code.

RajeshGupta

PostMessage

Kiran Pinjala22-May-07 0:44

Kiran Pinjala

22-May-07 0:44

I want to post a user defined message WM_PRINTLOG to the Main window in a Dialog based application from another thread started by the dialog.
That messag will be handled By a handler PrintLog(CString message) which prints the string(message) in to the edit box.

My question when i call PostMessage() how can i send the string (message) to the handler.
and how can i get the message at the ON_MESSAGE macro.

Thank you.

KIRAN PINJARLA

Nibu babu thomas22-May-07 0:58

Nibu babu thomas

22-May-07 0:58

kiran.pinjarla wrote:
ON_MESSAGE

ON_MESSAGE handlers have the following signature

<code>LRESULT SomeMessage( WPARAM wString, LPARAM lNotUsed )</code>
{
   if( !wString )
   {
      return 0;
   }

   CString* pString = reinterpret_cast<CString*>( wString );
   MessageBox( *pString );
}
 
UINT SomeThreadFunc( LPVOID lpvParam_i )
{
   CString csSomeCString = _T( "Nibu" );
   // Don't use PostMessage since it won't wait for your message
   // to be processed, but if you are <code>new</code>ing then it's
   // ok, delete in the invoked function.
   ::<code>SendMessage</code>( AfxGetMainWnd()->GetSafeHwnd(), WM_PRINTLOG, reinterpret_cast< WPARAM >( &csSomeCString ), 0 );
}

Nibu thomas
A Developer

Programming tips[^] My site[^]

Kiran Pinjala22-May-07 1:19

Kiran Pinjala

22-May-07 1:19

Thank you Nibu

KIRAN PINJARLA

Arman S.22-May-07 2:20

Arman S.

22-May-07 2:20

UINT SomeThreadFunc( LPVOID lpvParam_i )
{
   CString csSomeCString = _T( "Nibu" );
   // Don't use PostMessage since it won't wait for your message
   // to be processed, but if you are newing then it's 
   // ok, delete in the invoked function.
   ::SendMessage( AfxGetMainWnd()->GetSafeHwnd(), WM_PRINTLOG, reinterpret_cast< WPARAM >(&csSomeCString ), 0 );
}

Regarding to your comments. For user defined messages, people usually do Posting not Sending as PostMessage will return immedietly and thus lessen the thread delays. Use SendMessage if there is a reason for that.

Actually, your comment about newing and deleting is wrong. It is here we should either avoid of newing in a worker thread by posting it to UI thread or use SendMessage instead [opposed to what is said by comments]. The problem is the race condition [I'd say an obvious race condition]; if you PostMessage a newed object into another thread you may never be away whether that object has been deleted or not. A simple scenario is when the user closes the application jsut after the worker thread has done a PostMessage but before the UI thread ges informed about the message posted. Even with SendMessage you have to use some synchronization to avoid such unfavourable situations.

--
=====
Arman

David Crow22-May-07 3:05

David Crow

22-May-07 3:05

Arman Z. Sahakyan wrote:
people usually do Posting not Sending as PostMessage will...

...not cause a deadlock if the messagepump receiving the message happens to be in a blocked state.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

place FlexGrid in ATL window(CWnd Inheritance).

David Crow22-May-07 3:07

David Crow

22-May-07 3:07

kiran.pinjarla wrote:
My question when i call PostMessage() how can i send the string (message) to the handler.

Allocate it on the heap.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

thatsravi21-May-07 23:55

thatsravi

21-May-07 23:55

hi,

We are trying to place FlexGrid in ATL window(CWnd Inheritance).

Create is successful, but we cannot get Interface properly.

We think that either one or both of the arguments for "QueryInterface" are

incorrect.

iCannot find REFIID in the help header file.j

Please let us know the solution for this.

Confused | :confused:

Thanx & Regards

Ravi

DISP_FUNCTION

tom groezer21-May-07 23:14

tom groezer

21-May-07 23:14

I have a DISP_FUNCTION as below. the TBF parameter that needs to be filled is an enum value. How do I cater to an enum as a parameter in the DISP_FUNCTION.

DISP_FUNCTION(class, "method",method, VT_ERROR, VTS_I4 VTS_DISPATCH <tbf>)

Bmp Picture on DialogBox

anilkrupakar21-May-07 23:08

anilkrupakar

21-May-07 23:08

I want to have a picture of type .bmp or .ico on my DialogBox. so how can i do that. Can anyone help me. Thanks in advance

Anil Jillella

josip cagalj21-May-07 23:49

josip cagalj

21-May-07 23:49

On your dialog put picture frame left click than properties, select type (icom, bitmap)then select image (combo box offering you bitmaps or icons from res)!
Hope this was helpful!

anilkrupakar21-May-07 23:59

anilkrupakar

21-May-07 23:59

thanks,i myself found the solution.

Anil Jillella

KaЯl21-May-07 23:58

KaЯl

21-May-07 23:58

Add a static control on your dialog box using the resource editor, edit its properties, set its type to bitmap and specify the ID of the bitmap you want to use.