I have a large (35GB) AVI that is a raw (uncompressed) YUY2 capture. When I run it through avisynth (version 2.56) it periodically inserts a "future frame" into the sequence: as the video plays, there is a periodic "flash" of a single future frame. I know its not the source, since if I load the file in VDUB there are no poblems. And its nothing to do with my avisynth script, since I've reduced that to nothing more than opening the AVI file. I'm using the OpenDMLsource filter, and I've tried the source filters. None seem to make a difference. Strangely the exact location of the "flash frame" changes from time-to-time. And sometimes its replaced with an empty frame all in green. I know that the capture (which was done through VDUB) dropped a few hundred frames and am wondering if this is the cause. How do I stop this problem? I'm out of ideas. Suggestions much appreciated. KAR
Well what I would Maybe Suggest is to use an Earlier version of AVISynth as I believe version 2.56 is still in Beta Stage, Maybe Try version 2.55 which is the Stable version...Also you Might try Converting the Color Space to RGB 24/32 as Many apps do not like Video that uses a YUV Colorspace..... The Last thing I can suggest is to Not use AVISynth to frameserve, If Virtual-Dub can read the File Properly then maybe use it to Frameserve.... Good Luck
There isn't really an app in the mix yet. Just simple file processing. Anyway, the reason I'm using avisynth is to avoid the quality loss that occurs when VDUB converts YUV colorspace to RGB when it performs its processing.
Are you sure? I heard that the latest VDUB maintains colorspace so long as you don't use a filter (like crop, etc). Once you bring in a filter, VDUB changes everything to RGB.
Yes that is Possible...So Have you Tried Version 2.5 as opposed to 2.56?? It is the Version I use and I haven"t had any problems with it at all when working with Uncompressed AVI files... I use AVISynth with every file I encode to Mpeg-2...I generally use it with DivX/XviD Files and use filters Like the FluxSmooth,Undot,Convolution3D ,Lanczos Resize and the AddBorders Function...I especially Like it for Converting Pal to NTSC useing the "AssumeFPS" Function as it is the Only Program I know of that will Speed up/Slow Down the Frame Rate and the Audio at the Same Time while Keeping Perfect sync... well anyways Good Luck
Ok, I now know for sure that it is the dropped frames in the AVI that are causing the problem. When VDUB captured the original AVI, it dropped a few hundred frames along the way, and marked them as [D] frames. Avisynth seems unable to cope with these [D] frames. It seems to replace them with a "junk" frame. VDUB does what you'd expect, it simply re-uses the previous frame as a substitute. So, the question is, how do you get avisynth to handle dropped frames?
I no of no feature at all in AVISynth that will Fix your problem... The Only think I can think of is Maybe Try Makeing a New File with Virtual-Dub and see if it will Insert the Last good Frame instead of adding a D Frame Flag in the Video stream?
