Best Resolution To Encode At

[kejl89]

I was wondering what people thought was the best resolution to record a XVCD at. When I've tried encoding at 720X480 the movie got all blocky and messed up. But when I tried the regular resolution (352x240) it wasn't very sharp and was kind of blurry. People have also mentioned using 352X480, but wouldn't that distort the movie? Anyway, I would like to use 720X480, but does anyone know why it didn't turn out right? Or if you think the other resolutions are better, what settings do you use?

[Truman]

720x480=1350 macroblocks
352x240=330 macroblocks
352x480=660 macroblocks

The lower the resolution the blurrier the image.
Increase the resolution to get a sharper / more detailed image, but you have to increase the bitrate.
More macroblocks to encode = higher bitrate.

[vitualis]

352x480 does not distort the movie if your player can play it right. You need to understand the concept of "Display Aspect Ratio" or DAR.

The DAR of VCDs and SVCDs is always 4:3. That is, irregardless of framesize, the video is sized to fill a TV display (which has a DAR or 4:3).

Think about it; 720x480, 704x480 nor 352x240 are actually 4:3 in terms of framesize in square pixels are they? The reason they play properly is because the player knows that these video clips have a DAR setting of 4:3.

This is why SVCDs which have a framesize of 480x480/576 still play properly on the TV.

As for best resolution for XVCD, that will depend on your eyes. IHMO, you cannot make a video in MPEG-1/2 with a framesize of 704x480 or larger with an average bitrate of < 2000-3000 kbit/s without getting significant obvious MPEG compression artifacts in high motion scenes.

I think that 352/480x480 is a nice resolution to use (if it works on your player) as you can still get minimal perceptible artificing with relatively lower bitrates (e.g., avg. bitrate of around 2000 kbit/s) and have very good picture in terms of sharpness.

If not for artificing, you probably couldn't casually tell the difference in resolution between a 720x480 picture (i.e., DVD) and a 480x480 one (i.e., SVCD or some "X" variant) on a regular television.

Regards.

[sean madison]

LOL, hey man, 480x480 is what im encodin in with bitrates as low as 875 vbr and its lookin fantastic, no blocks at all. vbr ave- 875 max 1250 min-0

Technical aspects always go by the book.
I invent new things and secrets to bypass crappy quality.
Thats why i made the new VCD standard to fit over 80 min onto 1 cd in vcd standard compliancy, same way with svcd standard too.

There is nothing impossible with me.
Now, the largest res i have ever tried is 480x480, i have not yet tried 720x480, but i can guarantee you that when i ever will need to do 720x480, i bet i can make those blocks go away even if the source is only 352x240

[vitualis]

If you start from a source of 352x240 it is completely pointless to encode to a framesize higher than that as:

1. you do not gain anything in the increased resolution
2. the encoding will actually be less efficient
3. and your end image will probably be of a lower quality/fidelity as you've added an extra step of image processing.

You cannot fit > 80 min of video onto 1 CD and have it as a standard VCD, unless you use 90/99min CD-R (which really aren't standard either). If you think you can then you need to learn what a VCD is.

I applaud your enthusiasm but don't post crap.

480x480 with an average of 875 kbit/s VBR will have artifacts dancing all over the screen for anything with action (e.g., Matrix Lobby scene). If you can do that scene at such a low bitrate, then prove it.

Regards.

[Truman]

sean madison, well, "quality" is a matter of taste.
Aannd...you made a new standard? Come on, don't fly too high.

[kejl89]

So there is no way to make 720x480 look really nice since my DVD player's max bitrate is 2500? So then I should probably go with 480x480 or 352X480? If I did that, then I would want to go as high for the bitrate as possible, so what would I put as the average if I put 2500 as the max? And does increasing the average bitrate from 1750 to whatever you suggest help the quality a lot?

[kinneera]

Nothing is absolute. A very short (90 min or less) and/or low motion movie can look quite good at 720x480 at a variable bitrate with many encoding passes. It depends on what your priorities are and how much time you want to commit. Still 352x480 or 480x480 are typically the best compromise if your DVD player accept them.

[kejl89]

So pretty much what your saying is that if the movie has lots of motion, I should go with 352x480 or 480x480. Now, to get the best quality, I should increase the bitrate to the max, so if the max was 2500, what would I put as the average bitrate? 2500? I also have a question about Non-Interlace/Interlace. Which one should I use? And to answer you question about time, I don't care how long it takes, I just want the best quality possible.

[kinneera]

Yes, for a typical feature-length movie, with a reasonable quantity of motion/action, 352x480 or 480x480 is advisable.

As for the average bitrate, it depends on how many CDs you want to use. Then you whip out the bitrate calculator and figure out the appropriate average based on the length per disc. Widescreen movies can tolerate lower bitrates.

e.g. I typically prefer to put movies on 2 CDs (sometimes 90 min CDs), rather than 3. This usually yields an average bitrate anywhere from 1500 to 2000Kbps. The lower the bitrate, the more extra passes are going to help you.

Movies are film source, so they are originally progressive, which is to say non-interlaced. You will generally have to apply an inverse telecine or use some other method to eliminate the the extra interlaced frames, however. There has been plenty of prior discussion of this topic in the forums.

[Steveo]

The easy way out, is there template somewhere that I can download in to my template file to make a xvcd ? That way i can see maybe how good xvcd's can look.
Thanks

[kejl89]

Ok, I got all the settings figured out. The problem is that when I encoded a second movie, it got all jumpy. The first movie I did was an XVCD with bitrate average of around 1950 and the max was 2496. When I went to record the second movie, I had to lower it to 1550 for an average. First I thought it was the bitrate, so I rasised the bitrate and did a test, and it was still jumpy. It was like every 2 seconds it would pause for a very brief period of time. So then I tried a test from another movie using the same settings, and got the same results. And I checked the output file, I don't think there are any pauses in that. But I don't see how it could be the DVD player since it plays the first XVCD I made great. Oh and my DVD player is a Panasonic DVD-RV31 and I burned the XVCD using Nero. What am I doing wrong?