Blurred strip at the lower edge of the picture with LAV Video Decoder

[abolibibelot]

(Follow-up of this thread.)

Having finished the task which required the GAVC codec, I re-installed CCCP 32 bits, activated LAV Splitter for AVI as before, but Video Thumbnails Maker (with “Engine 2” rendering module) didn't work right away. Fiddling some more with various settings (unfortunately I don't remember the details of what I did), I managed to make it work, but now I get a blurred strip at the bottom edge of the picture, with patches of pixels moving haphazardly, and a sort of pulsation once per second. I made some tests with MPC-HC (the one included with CCCP), and Codec Tweak Tool :
- If I disable “ffdshow video decoder” and “LAV Video Decoder” in “DirectShow filters”, I get a correct picture, but VTM fails with that setting.
- If I disable “LAV Video Decoder” only, I get the blurred strip.
- If I disable “ffdshow video decoder” only, the video won't start.
- In CCCP I tried “Reset user settings” and “Repair CCCP”, to no avail.
Apparently, VTM needs both ffdshow and LAV decoders activated. It used to work fine, so what's going on, and what setting(s) should I fix ?

Preview picture generated by VTM / Engine 2 today (I tried several times, each time the blurred strip looks slightly different) :


Preview picture generated by VTM / Engine 2 on Nov. 19th, same video :

[abolibibelot]

So... noone here has any clue about that strange issue ?
Is it sumthin' that hasn't been seen ever since the Pliocene ?

Over there I read :
“Q : The image is corrupted during playback in many clips. libavcodec works fine.
A : 99% bad driver install. Need to reinstall the driver.”
Could it be the cause ? Which driver in this case ? The only driver I updated recently is “Intel Rapid Storage” (which seems to have partially solved the issues reported here – I get fewer BSODs although it's not fixed yet).
What about the remaining 1% ?

[abolibibelot]

Well, if not here, where can I get some help on that video-related subject ?
Should I say a password, or utter a magic spell to summon the good spirits, or ring a bell ?
Or should I make offers that can't be refused, even though I'm helpless and confused ?

[Budman1]

Not an expert on this type of thing but since no one answered... I would try several other players to see if some have a problem with slight variations in bit/frame rate.

[pandy]

Why are you using CCCP? Codecs packs are not recommended - IMHO they are source of many issues...
To investigate/debug such things graphedit may be useful - just render media trough graphedit and check which filters are used by system so you can debug your codec config... Anyway i strongly recommend to not use codec packs - just install LAV filters as decoder and desired codec as encoder filter.

[abolibibelot]

Why are you using CCCP? Codecs packs are not recommended - IMHO they are source of many issues...

It was recommanded on the support forum for Scorp Video Thumbnails Maker. And apparently it's based on LAV filters, which are supposed to be stable and non-conflictual, as opposed to actual packs of individual codecs.
“The CCCP was created to replace the codec packs provided by several anime fansub groups in favor of a single reliable pack capable of decoding practically any groups' files - without breaking compatibility for other formats. Since then it has grown into a pack that can decode more or less anything that you will run into during your travels on the internet. The CCCP attempts to be as unintrusive on your system as possible. Other codec packs tend to either randomly not work, break the system, or install far too much cruft. With CCCP, you know that when you install it properly, it just works.”
Is it just P.R. B.S. ?

To investigate/debug such things graphedit may be useful - just render media trough graphedit and check which filters are used by system so you can debug your codec config...

That's what I tried (using GraphStudioNext), right now it shows the decoding pathway as :
[input file] => [ffdshow] => [Video Renderer]
And from then I don't know what to do... I don't even know if the title of that thread is accurate : apparently this issue is caused by ffdshow, not LAV video decoder ; but if I try to manually insert “LAV video decoder”, and connect the box to the input video, and to the “Video Renderer”, it doesn't work at all (video window stays black). If I try to connect “ffdshow” to “LAV video decoder” to “Video Renderer” (which might be a total absurdity – like I said I don't know what I'm doing here !), it says “VFW_E_NO_ACCEPTABLE_TYPES”. If I disable H.264 in ffdshow's settings, doesn't work (GraphStudioNext shows “LAV Video Decoder” in place of “ffdshow”, just like when I tried to set it like that from there, and video doesn't start at all). If I set H.264 to be decoded with “Intel QuickSync”, the picture looks correct in MPC, but the screenshots made by VTM still have that blurred strip. If I set H.264 to be decoded by “LAV Video Decoder” again, MPC displays that blurred strip as well. With Codec Tweak tool, in “DirectShow Filter Configuration”, if I remove “h264” from “formats” in LAV Video Decoder settings... it works anyway... but with the blurred strip... Same if I remove “avi” from “input formats” in LAV Splitter settings... In “Codec and Filter Management” / “DirectShow (x86)”, if I disable “ffdshow video decoder”, I get a correct picture in MPC, but VTM fails (and strangely GraphStudioNext now shows the input video connected to... nothing... then how can it work fine in MPC ? – for these tests I use the version of MPC included in CCCP, which is quite old and doesn't seem to have its own embedded decoders, that's the point I guess, it's included in there because it's supposed to rely on CCCP entirely).
Again, this used to work fine about two weeks ago, before I uninstalled CCCP, I'm just trying to get back to that working configuration.

[pandy]

You can reduce ffdshow priority (merit) thus other codec will be preferred. Hope ffdshow is configured correctly (be aware that there is DShow and separate VfW ffdshow configuration).

Personally i use only LAV filters and separate XVid VfW codec - that's all. Seem everything is decoded correctly.

[jagabo]

Or disable h.264 decoding in ffdshow.