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Thanks Rajesh.
Rajesh R Subramanian wrote: But until you use it, the older value exists
I understand. But how do I use it? I just want to test this.
I have created a big array in the main() and assigned some values to each element thinking that it will use the stack space, but still my old value exist. I am sure that I am doing something wrong. Any ideas?
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Christian Flutcher wrote: I understand. But how do I use it? I just want to test this.
You will not be able to write to a location after the control comes out of it's scope of existence, because now do not have write access to that location.
If you are keen to see yourself rewriting the contents of that 'particular' portion of memory, try a placement new:
Is there a way to force new to allocate memory from a specific area?[^]
Christian Flutcher wrote: I have created a big array in the main() and assigned some values to each element thinking that it will use the stack space, but still my old value exist.
Yes, the stack is simply 'big enough' to hold it all. Besides that, it is an unnecessary exercise to wipe off the contents of the memory location 'as and when' it is freed. Erasing the contents of the freed memory every time will degrade the performance severely.
To tackle this, the memory manager marks that portion of memory as 'available for use', and this will be treated as free memory and the old contents will be replaced with new content, when the program writes to that portion of memory.
Hope that helps. 
Many are stubborn in pursuit of the path they have chosen, few in pursuit of the goal - Friedrich Nietzsche
.·´¯`·->Rajesh<-·´¯`·.
[Microsoft MVP - Visual C++]
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Rajesh R Subramanian wrote: Hope that helps
Indeed. Thanks for the help.
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Rajesh R Subramanian wrote: To tackle this, the memory manager marks that portion of memory as 'available for use',
I'm not an expert on the stack but I guess there's even no need to mark some memory blocks as available. It is a stack, so it means that things that are 'pushed' (e.g. memory allocated on the stack) last on the stack needs to be 'popped' (freed) first. So, simply having a pointer which points to the top of the stack is enough. That's also the reason why allocating memory on the stack is much faster: you just allocate a certain amount of memory on the top of the stack. No need to search in different memory regions to find a block which is big enough (which is the case when you allocate memory on the heap).
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I rather intended explaining conceptually how the MMU works, not being specific to stack. I was wanting to explain him the usage of placement new (as in the heap) as well, so got slightly messed up.
Thanks for pointing out.
Many are stubborn in pursuit of the path they have chosen, few in pursuit of the goal - Friedrich Nietzsche
.·´¯`·->Rajesh<-·´¯`·.
[Microsoft MVP - Visual C++]
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Hi @ all,
After recording sound with the Wave Methods of Windows media Lib, I want to process the data for a RTP Packet.
That´s my problem whereat it is hard to find any good information.
What exactly I have to do with the captured sound?
Must I compress it before i can encode it to G 711 uLaw or what else I Have to do?
Hope anyone here knows about the handling of sound for sending it with RTP.
I record the sound with WAVE_FORMAT_PCM and 8000 SamplesPerSec by 16bitsPerSamlple.
Greetings
Karsten
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You can use the Audio Compression Manager[^] to convert
your PCM samples to G.711.
Mark
*edit* fixed the link!
Mark Salsbery
Microsoft MVP - Visual C++
![Java | [Coffee]](https://www.codeproject.com/script/Forums/Images/coffee.gif)
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Are there any examples how to use the ACM?
And the second problem I don´t understand exactly is how I have to make the frames adapted to
the size I need? Also after recording I need frames of 20ms. Can I simply cut 160 Bytes from the buffer?
And after receiving my RTP Packets? Must I assemble the Data from the Packet before I have to playout the buffer?
modified on Wednesday, September 24, 2008 3:41 AM
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CrazyDogg wrote: Are there any examples how to use the ACM?
See the "Using the Audio Compression Manager" section at the link.
CrazyDogg wrote: I don´t understand exactly is how I have to make the frames adapted to
the size I need?
That can get tricky because different codecs have different granularity.
You can easily use the ACM functions to examine different compressed formats
to see if 20ms granularity is possible.
I personally capture samples in 20ms chunks, so yes, you can cut 160 bytes of
samples from the buffer.
CrazyDogg wrote: And after receiving my RTP Packets? Must I assemble the Data from the Packet before I have to playout the buffer?
Yes - you have to. If the samples have been converted to another format
(than PCM) you'll need to convert them back to PCM.
Then you have to deal with jitter, lost packets, and if you're doing
capture/playback in real time (like teleconferencing) you need to
deal with clock drift.
Mark Salsbery
Microsoft MVP - Visual C++
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I have an MFC program where the path of a WMV file can be entered. I'm just looking for a simple way to get the number of audio channels from the entered video.
Thanks in advance.
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The Windows Media Format SDK[^] has all the functionality
for working with ASF files (like WMV).
Lots of sample code in the docs!
Mark
Mark Salsbery
Microsoft MVP - Visual C++
![Java | [Coffee]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/coffee.gif)
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Hi,
I am developing a dialog based application in MFC. In my application i have a multiline edit box. For that i have added scrollbars. Scrollbars are working in WindowsXP. But if i run my application in WindowsVISTA scrollbars are not appearing for the edit box. Can any one tell me where it is going wrong? 
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hari_honey wrote: i have added scrollbars.
Using what code?
Mark
Mark Salsbery
Microsoft MVP - Visual C++
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Hi
I've downloaded free Interbase library - IBPP.
What I must do to use it as <ibpp.h> instead of "..\ibpp\ibpp.h" in my project?
Do I have to move IBPP files from my project folder to ... ?
P.S. I'm new to the C++ scene so if you can write more details of how to do this in MSVS 2005 or DevC++.
Thank you in advance,
Ani
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I didn't fully understand what you were asking but I guess that you want to avoid specifying the full path to the include files in your sources, is that right ? If, yes, you have to specify this in the "additional include directories" option. For VC2005, open the project settings -> "C/C++" -> "General" -> "Additional Include Directories". There add the path to the include dir of the library.
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Well basically in my code I want to write:
#include '<ibpp.h'>
(I use ' just beacuse of the tags)
instead of
"..\IBPP\ibpp.h"
I know that I have to use static library, but I have no clue about them
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Well, and what is the problem with the solution I gave you ? 
And why do you want to use <> instead of "" ?
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akirilov wrote: Well basically in my code I want to write
no, don't !
<> is meant for the compiler that the include is to be searched from the includes in its installation folder.
this is a C/C++ standard language feature and it is not what you want.
what you want is to reduce the path in the include instruction, don't you ?
well, if you include in the project settings the path to the folder containing the ibpp.h header file, you will then be able to do the following:
#include "ibpp.h"
so, not using <>, but you reduced the relative path included.
do that satisfy you now ?
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Personally I don't care if it going to be <...> or "...".
However, I have to change some things in a project written by someone else and ... I can't compile it ... for now. I hoped that if I try to stay as close to the environment that the other guy had, I will compile it.
The program was written in DevC++ 4.0 ... no project, just a make file (can't compile trough it).
I receive: [Linker error] undefined reference to IBPP::CheckVersion(unsigned int)
and so on for all functions inside.
So, this is the main reason for my question ... and I hoped around it to learn more about static library.
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Hi All,
Can anyone please tell me whether may I debug a microsoft function like strcpy or IStoreNameSpace: RegisterNotification() or any othe MS functtion?
Thanks!
dolly,
N,IN
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If the source is available, you can set a break point and step into the source. If the source is unavailable, then you cannot do it.
What does it have to do with if it is a function written by MS or not?
Many are stubborn in pursuit of the path they have chosen, few in pursuit of the goal - Friedrich Nietzsche
.·´¯`·->Rajesh<-·´¯`·.
[Microsoft MVP - Visual C++]
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why ? your application is crashing in there ?
here is a better advice : fix you code. strcpy() is certainly not the cause.
so, please show your code...
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Actually strcpy() is just an example but I am facing a problem with another function, in Windows Mail plugin, it's a COM DLL written in 'c' language, and IStoreNameSpace: RegisterNotification() method fails there....and the last return code which I get is not implemented.
dolly,
N,IN
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I am getting the return code from this function as 0x80004001
dolly,
N,IN
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