Progressive source or Preserve Interlace???

[ionutvasilescu]

Hi all!!! I have an inssue that I'm not very sure about:
I compress captured video from digital cameras. I use VirtualDub. I use deinterlacing filters (smart deinterlacer or the built-in deinterlacer of VDub). In DivX - compression - configuration, what should I use, for the deinterlacing option: "progressive source" or "preserve interlace"???
As I know it, progressive source should be used for the video captured from analog cameras (because the record without any interlacing).
Thanx!![/b]

[guns1inger]

If you have already deinterlaced then you now have progressive footage. What interlacing is it going to preserve ?

[SLK001]

For DV camera footage, always keep the native format. If it was recorded "interlaced", then maintain the interlacing, because the interlaced fields contain unique information. If it was recorded as true progressive, then encode as progressive.

[ionutvasilescu]

Mmmm, I asked this because I'm not sure about somthing: which is the order that VDub follows in operations. I mean, FIRST of all, the filters are appllied, and THEN the compression (with the selected codec) is made??
if so, isn't it better to apply a resize filter AFTER the compression is finished?
Thanx all....

[edDV]

A basic rule of digital filtering (e.g.resizing) - apply filters before compression. There are exceptions.

As for sources, your statement is unclear.

If you are talking about a still digital camera,then you have a progressive source. If you have an analog or digital camcorder then you have an interlaced source. If your goal is a standard DVD,then you should keep it interlaced.

[SLK001]

if so, isn't it better to apply a resize filter AFTER the compression is finished?

Actually, you CAN'T apply a resize filter AFTER compression, unless you want to RECOMPRESS again.

[ionutvasilescu]

My source is interlaced.

edDV wrote: "If your goal is a standard DVD,then you should keep it interlaced".
Why? Why should't I deinterlace even I make a standard DVD (with Pinnacle, for example). Until now I've only made DivX and XVid compressions. I had to deinterlace, because the orizontal lines (interlacing) were very annoying. Don't these lines appear in a standard DVD format, too?

slk001: I'm sorry, that was a stupid question of mine. I realized that after posting the message, but I did't bother to edit it again.
Thanx,

[SLK001]

My source is interlaced.

edDV wrote: "If your goal is a standard DVD,then you should keep it interlaced".

Why? ... Don't these lines appear in a standard DVD format, too?

They show up more noticeably on a computer display, because the persistence is very short. On a TV the persistence (of the phospher screen) is much longer, so the lines blend together quite well.

[junkmalle]

My source is interlaced.

edDV wrote: "If your goal is a standard DVD,then you should keep it interlaced".

Why? ... Don't these lines appear in a standard DVD format, too?

They show up more noticeably on a computer display, because the persistence is very short. On a TV the persistence (of the phospher screen) is much longer, so the lines blend together quite well.

No, NTSC TV displays 59.94 fields per second. You don't see interlace comb lines because You never seen an entire frame on a television screen. By the time a field is being drawn the previous field has faded away.

Computer monitors are progressive scan. You see both fields at the same time, all the time. Since you're looking at alternating scanlines from two separate pictures you see interlace comb lines.

[ionutvasilescu]

What I ment with my initial question was this: if I apply a deinterlace filter, so I get a deinterlaced movie (source), then, when compressing with DivX, should I set it to "preserve interlace" (although my source is now deinterlaced, so there is no interlace to preserve), or should I set it to "progressive source", assuming that a source that has been deinterlaced, became a progressive source??
To be honest, I've tried both ways and I can't observe any differences, though there might be some.
Thanx,

[edDV]

What I ment with my initial question was this: if I apply a deinterlace filter, so I get a deinterlaced movie (source), then, when compressing with DivX, should I set it to "preserve interlace" (although my source is now deinterlaced, so there is no interlace to preserve), or should I set it to "progressive source", assuming that a source that has been deinterlaced, became a progressive source??

If you deinterlace it, then you present a progressive source to the next process.

Deinterlace is very destructive to the video. It is appropriate for certain applications, such as extreme compression intended for computer only display (i.e. a progressive display), but if the goal is interlaced TV display, then deinterlace should be avoided.

If you don't like viewing the scan lines on a computer monitor, use a deinterlacing player like PowerDVD. That way you can maintain the interlaced source for DVD authoring if DVD is your goal.

[ionutvasilescu]

edDV wrote:

If you deinterlace it, then you present a progressive source to the next process.

Deinterlace is very destructive to the video. It is appropriate for certain applications, such as extreme compression intended for computer only display (i.e. a progressive display), but if the goal is interlaced TV display, then deinterlace should be avoided.

If you don't like viewing the scan lines on a computer monitor, use a deinterlacing player like PowerDVD. That way you can maintain the interlaced source for DVD authoring if DVD is your goal.

I usually fit one hour of movie (captured from DV camera) on 1 CD. I have this crazy ideea to make CDs (not DVDs) at a as high as possible quality. If movies everywhere in the world fit on CDs, why couldn't I do the same. I make AVIs that are to be seen on computers, not TVs. Of course, it's easier with the DVDs ment for TV display.
So, I compress the raw AVI from about 13.5 GB to about 650-700 MB. Deinteracing is very important, although it's destructive (more or less, depending on the deinterlacing filter you use).

[edDV]

...
So, I compress the raw AVI from about 13.5 GB to about 650-700 MB. Deinteracing is very important, although it's destructive (more or less, depending on the deinterlacing filter you use).

That is one way to do it
Do you shrink to 320x240? Which deinterlacer do you use?

For movies, I'm kinda operating at the other extreme these days, capturing HDTV cable to standard 720x480 DVDs with 90-120 min per disc. I either real time encode the MPeg2, cap to DV or cap the HD TS file and then encode in a second pass.

I bet we use similar amounts of computer CPU time.

[ionutvasilescu]

edDv wrote:

Which deinterlacer do you use?

Depending on the source. I think I like the "Smart Deinterlacer" filter better. I would be very interested in using the MGU Deinterlacer, though it's not free for downloading. They say it's the best deinterlacing filter. I also use other MGU filters, such as MGU Denoiser or MGU Smart Brightness.
I DO NOT resize the movie. Because I want it to be played on a monitor. on full screen, I leave it to PAL resolution 720x576. I've also tried to resize it to 640x480 or 512x384 (to gain some filesize), but the lower quality is obvious on full screen. On a 17'' LCD monitor, at 1280x1024, even 720x576 isn't enough, but it's the best that can be done.
Of course I use 2 pass compression. Ieven tried with 3 pass, but there was no significant difference, neither in the quality, nor in the filesize.
A 2 pass compression, with all the applied filters, takes about 13-16 hours[/quote]

[Abond]

The best deinterlace filter is TDeint for avisynth IMO.

[ionutvasilescu]

Well...I don't do scripts. I just use VDUb or any other friendly looking software. So I don't know Avisynth, although I know it's a powerfull tool. I do capturing and compressions just for fun, in my spare time and it's very few.