Theory About CRC Errors

[magubbi]

Hi,

My theory is that the CRC patch is evil. It helps you effectively ignore CRC errors, but that doesn't mean they aren't there!

I have encoded a couple of movies where everything went perfectly, but when I tried to watch the movie, there would be a point where the quality of the movie would start degenerating. It would start out as a glitch, an instant of blockiness and that electronic scratching sound. It would get worse until the whole movie just froze. What I think is that CCE tried to warn me about it while I was encoding, but the CRC patch disabled the warning.

We need to find a REAL way to fix CRC errors instead of ignoring them by applying a patch. Since CRC errors rise when a pass doesn't check correctly with the previous pass, would it make sense that doing less passes would decrease problems? Any other ideas?

[auenf]

a guaranteed way to fix it (unless the CRC are caused by instabilities in your mobo/cpu/mem) is to encode from an .avi rather than from a script.

Enf...

[magubbi]

Hi,

Can you tell me how to do this? Or is there a guide somewhere?

Thanks,

MGB

[arcman]

Well, are you referring to the CRC error patch for Athlon processors? If yes then I have nothing else to say than I get CRC errors if there actually is difference between the runs. Like once I forgot to delete the old referene file before restarting encode after making slight changes to the videodata.

I have not seen any glitches or quality degrade with the patch applied. Without it, I could not encode anything...

This is not a definite answer ofcourse but it is something I have noticed on my tests.

[auenf]

Originally posted by magubbi
Hi,

Can you tell me how to do this? Or is there a guide somewhere?

Thanks,

MGB

use a DV or MJPEG or LMJPEG codec and a lot of hdd space and save the output to avi, rather than frameserv to cce, using one of the codecs i mentioned, then you can take the saved avi straight to CCE.

major points to mention:

- DV will create the smallest file size, but that is still 3.6MBytes/s, MJPEG and LMJPEG are bigger, but are scalable.

- CCE 2.50 will not accept AVI files that are over 2gb, 2.6x will if its a directshow file, workaround is to frameserv the avi (without any filters applied) from virtualdub to CCE, which should bring up CRC errors (in theory).

- a free vfw DV compression codec doesnt exist, and DV is restricted to 720x576 or 720x480 resolutions, vfw mjpeg codecs are more available.

this might be a fair bit of work/hassle, but CCE was made to encode from .avi, not frameserved files.

Enf...