Question about resolutions

[ShinKyo]

The resolution of my source video is: 512x384 rmvb

Now I want to convert it to mpeg2. Question: is it better to convert to 720x576 or 352x576? Given the resolution of my source, which of the above resolutions will look better on TV?

[jagabo]

Do you want to lose more resolution?

[lordsmurf]

"Losing" all depends on the original source, before the 512x384 rmvb compression, and whether or not the encoded file (the current "source") has softening filters or not -- and I bet they do.

352x576 is probably going to be identical

[ShinKyo]

So you guys suggest 352x576?

[ShinKyo]

BTW I dont care if I loose resolution or not, I just want the better pictue quality when watching it on TV.

[FulciLives]

I vote for Full D1 resolution (720x576 for PAL or 720x480 for NTSC).

I would only go with Half D1 resolution (352x576 for PAL or 720x480 for NTSC) if you think that you don't have "enough" bitrate to use for the encoding. In other words Half D1 tends to look better than Full D1 when using low bitrates or with a very "noisy" video source (again when using anything but a very high bitrate).

Resolution wise though you get a slightly sharper image with Full D1 in this case BUT then again Half D1 probably won't look that much "worse" either.

As LordSmurf said the resolution of the source could also play into it.

But like I said I would go with Full D1 resolution assuming a decently clean source and that your bitrate isn't going to be "low".

- John "FulciLives" Coleman

[jagabo]

You don't care if you lose resolution? What if you reduced the frame size to 1x1 pixels? (This isn't DVD compatible of course, but you could 14,000 hours of 30 fps uncompressed RGB on a DVD!) How good would your picture quality be then? Obviously, resolution is a part of picture quality.

If the video is blurry and of low detail you will not lose anything of consequence when reducing the frame size from 512x384 to 352x576 or even 352x288. But if it's clear and has any detail using 720x576 will retain more of that detail.

The running time of the video will have some bearing on the issue as well. If it's less than two hours long and you are using single layer DVDs 720x576 should probably be your choice. If you need to put more than two hours on a DVD you'll want to step down to 352x576. What you are doing is trading off spacial detail in order to get fewer macroblock artifacts.

"Two hours" is a very general rule. A 4 hour long static shot of a bowl of fruit would look just fine at 720x576. A 1 hour long video of white water rafting in broad daylight from a head mounted camera will look like crap at 720x576.