[title edited by Teegedeck:] Interlacing: XVID and DVIX Encoding Problems

[Horas]

Well hello everyone, I am a noobie to filmmaking. So please be gentle ^^
I am using XP SP2 on a Asus A7N8X Deluxe Mainboard with Athlon 1800+ Processor. Grafics: Radeon 9600, Ram 1032 MB

I tried several Versions of XVID and DVIX and it still happens to me everytime that there are problems with every "move" on the video (I tried captured Videomaterial and I tried from MiniDV captured material with several programs (mostly Magix Video Deluxe 2004 Plus). There are no problems with the moving if I encode it at Realmediaformat. But I need it as avi.
So the problem is, that everytime somethings moving in the video there are horizontal black lines over the moving object.
I made a screenshot.
I appears no matter what I tried to keep it away (resolution...) and it doesn't appear in original or minidv or realplayer... Seems to be a problem with some pictures being overlayed wrong??? The Original has 30 frames per second and so has the encoded video. I don't know what to do *sniff* *sign*

Thanks anyway

Horas

[Teegedeck]

The phenomenon is called 'interlacing'. (It could also be telecining as your source is NTSC.)

Have a look at video basics (http://www.doom9.org/index.html?/video-basics.htm) to understand what that means.

What you need is a deinterlacer (or an IVTC filter). Like TDeint, TomsMoComp, Decomb, TIVTC or similar. Please search the AviSynth subforum for more information.

Deinterlacing is not a very nice topic to read, arguably. Perhaps you'd find encoding with an automated solution that also deinterlaces automatically good enough. Try AutoGK. (http://www.doom9.org/autogk.htm)

[Thread moved to Newbie subforum.]

[jggimi]

If the source video is DV, then this is interlacing, not Telecining. That means that all you need is a suitable deinterlacer.

Captured content may have been Telecined. It will depend on whether the original source was film or video camera.

IVTC -- Inverse Telecining -- should only be used on Telecined content.

Telecining is the process of transferring 24fps film (35mm or 16mm) to NTSC video, and Inverse Telecining reverses that process.

See www.doom9.org/ivtc-tut.htm for more on how to tell the difference between Telecined and Interlaced content. Its a dated tutorial (for example DVD2AVI has been since replaced by DGIndex) but still should be helpful.

[Horas]

okay, thanks.

I read the forums and your links now for some hours. Some things are now clearer to me, some are not.
Actually I took a interlaced avi and reencoded it with vdub and now it is better with the artefacts. But what I don't understand is why the interlace happens in the first place. I mean I captured videomaterial with Fraps (30 f/s) I worked with it in Magix Video Deluxe 2004 Plus and made an output with 30 f/s. I don't see WHERE there should be any change from NTSC to Pal or something like that. I don't rip anything.
And if I capture video with Magix (tried other programs as well) from my Camera the video is not interlaced it only becomes it when i try to encode an avi... (and not with realplayer etc). Should there not be a possibility to encode it as avi just as it is captured, so there is not interlace there in the first place? It doesn't makes a lot of sense to interlace it and then deinterlace it.. so how can I prevent the film from being interlaced? (other resolution??)
The Original source I am using at the moment has 640x480 with exactly 30.0 f/s.. everytime I try to encode it with exactly that information I only get the interlaced video... damn I didn't know it was that complicated...

Horas

[Elic]

Horas
> if I capture video with Magix (tried other programs as well) from my Camera the video is not interlaced it only becomes it when i try to encode an avi
Try to look your captured video closely and freeze-frame. Maybe your capturing software does deinterlace automatically during preview or capture only (so many TV-watching software do that), or hardware deinterlacing may take place during preview, or preview shows in small window (240 pixels height or less, thus only one field is shown).

[jggimi]

Fraps, et. al. are captures of PC application graphics, they are not Television.

Standard television signals are usually interlaced, because standard TVs are interlaced. Most NTSC video cameras are interlaced, too, including most DV camcorders.

That means, 59.94 times per second, a field is recorded. For NTSC DV, if I recall correctly, the bottom field is recorded first, then the top field.

As you know, each field is only 1/2 the total image, together the two fields make a complete frame.

But ... the two images are not taken at the same time. They are taken 1/59.94th second apart. If there is any motion -- of the subject, the camera, or a pan or zoom ... the individual fields will show differences -- if you looking at a single frame, you will see these differences as interlacing artifacts.

When you play back a DV image on a TV, you won't see these differences, since a TV is an interlaced device. It displays one field at a time. But, when you play these back on a progressive device, such as a PC, you will see these artifacts unless deinterlacing is performed. Except when the height of your playback is at 1/2 the source, or less:

NTSC DV is 720x480 ... each field is 720x240. If you play back your video with a height of 240 or less, you won't need a deinterlacer.

tandard Definition video is usually interlaced (eg: 480i). High Definition TV standards allow for either interlaced or progressive video (eg: 1080i, 720p). PC monitors are progressive. When you watch interlaced content on a PC -- such as an interlaced DVD through a software DVD player, the player is deinterlacing the content.

AVIs are expected to be progressive. That is why you see interlacing artifacts.

Telecining is confusing, because it appears to produce interlacing artifacts. But it is not interlacing as a video camera interlaces. It is converting frames into fields, and duplicating fields, to accomplish a framerate conversion.

[Horas]

@Elic, the captured source video files are all without any artefact.. it is completely perfect. Looked at it closely. The only thing that could be a problem is that the captured video doesn't seem to have the 30 f/s needed (because my PC Hardware isn't good enough, so fraps slowed down the captured program so all the pictures are captured but not with 30 f/s)

@jggimi humm, yea, and because they are not television I don't know why there should be an interlace. Humm, thanks for information, was not aware that my camera captures interlaced.. thought it would be perfect after capturing, will test that soon.
Just to say.. I tried to make the video from 640x480 to 320x240 so the interlace should not be there but it IS still there. God doesn't like me :D

Well I found a way to show only first half of the Frames.. so it is not interlaced.. (is this a way to force the avi not to be progressive?) I really don't know how the program (magix) makes this without resolutionproblems and still don't know exactly why it was interlaced with a perfect source and same framerate (at least on paper) but anyway. It has quality reduction.. but still better than having an interlaced video and removing it (because this has quality reduction as well and not all the interlace is removed..)

:thanks: to you guys! Thanks for helping

Horas

[jggimi]

..the captured source video files are all without any artefact.. Capturing PC window pixels is not capturing video. Fraps and similar tools capture PC grapics, and place the resulting frames into a video file....I tried to make the video from 640x480 to 320x240 so the interlace should not be there but it IS still there...DV is 720x480. So now I'm confused about what your sources actually are.... Let's deal with your video content, so as not to confuse each other.

DV from camcorders should be copied to hard disk as either a Type-1 or Type-2 AVI. If what you see is 640x480, then it has already been resized. It might have been deinterlaced, too. How are you examining your sources to determine that there are no artifacts? And then, how are you resizing? I don't know the toolsets you are using; for DV, I recommend reading through the stickies in our DV forum.

If you store DV as Type-2 AVI, you can open them in an editor such as VirtualDub or VirtualDubMod, and then "scroll" through the frames one by one. In addition, you will see the frames as they were stored -- unresized (720x480), and without any deinterlacing filters....Well I found a way to show only first half of the Frames.. so it is not interlaced..I do not understand what you mean by this. If you look at Teegedeck's link on video that he provided, above, you will see what individual fields consist of, and then, how two fields make up a complete frame.

[Horas]

well I captured a video from a game (final fantasy 8) with fraps. That is why I am talking of "video". And that's why the source is 640x480 (Virtual Dub told me it is 640 x480)
I didn't try DV at the moment, as long as I don't manage the other files I can't really work (no space available on HD). Last time I put DV onto my computer (and when I had interlacing problems too) I captured it with a cutprogram over firewire... don't really know what it did.
And yes, I checked the source from the game with virtual dub (no interlacing problems) it only appears every time I try to make a normal avi-file (no matter what resolution or f/s) It may be a problem with fraps. I told it to capture 30f/s and maybe my computer sucks so much it just does not get that much.. so maybe the cutproggie has problems with that. And I made some scenes faster or slower in the cutproggie.. maybe then it has to interlace because of other framerate??

well in MAgix there is an option. It is in the menue: frame-type then there are 3 options: 1. Fullpicture 2. Halfpicture A 3. Halfpicture B
I chose the second and now it seems to work.. i don't know what it does exactly.. no clue. But in Virtual Dub it seems to be quite ok.. quality not that good anymore but thats normal with encoding - I think.

Horas

[Guest]

You deinterlaced by discarding a field. That's a poor way to do it.

[Horas]

lol, yea, I thought so, but deinterlace with other programs is not perfect (even worse in my opinion in quality) and I REALLY don't know how i can stop it from being interlaced in the first place *sign*

[dr.schanker]

in the timeline you can right-click on your video-clip and select "objekt-eigenschaften" (object-properties). there are some options regarding how VideoDeluxe handles your video (interlaced/progressive). the program automaticly tries to detect the proper mode, but often it failes.
maybe this helps, good luck.

[Horas]

Thanks Dr. Schanker. I tried now everything and there is an option where you said that I can interpolate (interpolieren.. oh well my english...) somehow it seems like Magix interlaces the video-source no matter what I do just by importing the video.. maybe because it is 640x460 and 30f/s and because the program thinks that is to unusual to have that format :confused:
Well, anyway interpolate makes it a bit better, but there are still are interlacing effects that really kill me. I tried everything with Xvid that is possible. Since my camera isn't working at the moment I cannot test other things. But I am sure that everything else I would import from anywhere would be interlaced (it was everytime I tried.. although the source always works without any interlacing).
If you know a program that never made any trouble importing from MiniDV and Fraps (I tried several..) then please tell me. I am discarting the field now until I find another solution to this problem. :(
Thanks for reading and trying to help.