[Approved] Fix for stuttering/corrupted streaming of live tv (2 Viewers)

[miroslav22]

@disaster

That's strange, would you mind posting the full tswriter from the server and tsreader from the client?

It certainly looks like that clock jump is the cause. Does it seem to happen randomly or only on certain channels etc?

Edit: MP pre-allocates the file size using SetEndOfFile

 

[disaster123]

AW: Re: Fix for stuttering/corrupted streaming of live tv

@disaster

That's strange, would you mind posting the full tswriter from the server and tsreader from the client?

It certainly looks like that clock jump is the cause. Does it seem to happen randomly or only on certain channels etc?

Edit: MP pre-allocates the file size using SetEndOfFile

Sorry they're gone but i can try to create new logs.

> Edit: MP pre-allocates the file size using SetEndOfFile
But without SPARSE file set it really needs to create a file of that size - that's reall bad. Could you point me to the line number and file? I'll then include SPARSE and see if it helps.

Under Vista and / or Win7 it should use something like this (code borrowed from a DS Filter by me):

	DWORD cch = 0;

    if (!DeviceIoControl(m_hFileWrite, FSCTL_SET_SPARSE, NULL, 0, NULL, 0, &cch, NULL))
    {
		Log("SetNewFileSize: Couldn't set sparse - working without sparse");
	}

    LARGE_INTEGER fsize;
    fsize.QuadPart = dsize;
    if (SetFilePointerEx(m_hFileWrite, fsize, NULL, FILE_BEGIN) == INVALID_SET_FILE_POINTER) {
	   Log("SetNewFileSize: Couldn't SetFilePointerEx of file %I64d", dsize);
       return E_FAIL;
    }
    if (!SetEndOfFile(m_hFileWrite)) {
	   Log("SetNewFileSize: Couldn't set end of file %I64d", dsize);
       return E_FAIL;
    }

 

[miroslav22]

not sure... why do you think the files should be set as sparse?

I thought that just stopped a file physically taking up more room than it's actual written size (ie a kind of compression for say a large paging or database file). Unless i'm not understanding something?

I haven't actually changed this part anyway, but it's in FileWriter around line 211

			SetFilePointer(m_chunkReserveFileSize, FILE_BEGIN);
			SetEndOfFile(m_hFile);
			SetFilePointer(currentPosition, FILE_BEGIN);

 

[disaster123]

AW: Fix for stuttering/corrupted streaming of live tv

As far as i remember correctly: When you create a large file and don't create it as sparse it will take a lot of time to set SetEndOfFile. But i already modified the code and will report back if that will help - just waiting for my wife going to bed to start testing ;-)

 

[miroslav22]

I think SetEndOfFile only reserves the blocks for the file so should be pretty quick. I think it might only be detrimental if the disk was very fragmented and nearly full. It's worth a try though - let me know if it helps

 

[disaster123]

AW: Fix for stuttering/corrupted streaming of live tv

mhm you might be right ;-( i will try it anyway. Do you have any idea why tsreader is always jumping between the first and last ts buffer file?

 

[snowball]

Hi,

first many thx for this patch. running MP 1.1.2 with your V3 of the patch and mainly all problems with stuttering and artefacts have gone.
i am experiencing only one interesting effect.
i have multiple clients attached to the server. and when both clients are watching TV it can happen that at Client 2 the TV starts stuttering (bascially looks like only every 50 picture is shown). only thing that helps then is rewind a bit at Client 1. Then it works again at Client 2. interesting is also that it only appears at Client 2 and always client 1 has to rewind.
i have the feeling as the internal clock or the TV on Client1runs faster and it reaches the end of the timeshift file.
Ive activated the extra debug output in the streamingserver.dll (tsbuffer.cpp in Require) and actually it seems that the streamingserver runs at the end of the file.
ill see that i can capture logs the next time it happens.

does someone have the same problems?

Cheers Snow

 

[disaster123]

AW: Fix for stuttering/corrupted streaming of live tv

miroslav22
main problems i'm seeing:
1.) Tsreader isn't thread safe and the progressbar / tsduration.c does also access the same reading function like the filter itself
2.) tsduration does seek from the 1st file and the last file about two times a second. That's why tsreader starts to jump between first and last file

 

[disaster123]

AW: Fix for stuttering/corrupted streaming of live tv

miroslav22
I was able to fix my stuttering with some more modifications to your patch. I would like to present a patch on top of your patch.

 

[disaster123]

AW: Fix for stuttering/corrupted streaming of live tv

here are the binaries for 1.2 SVN - please use them only on TOP of miroslav's V3 patch.