New Program : AVI to DVD Resolution Calculator

[guns1inger]

There have been quite a few posts recently asking "How do I correctly calculate the new resolution of my AVI when converting to DVD ?", and even trickier "How do I make it 16:9 ?"

To make life easier I spent a couple of hours this afternoon writing a small app to do just that. It is simple, only works for full-D1 conversions at present, and has pretty basic error checking. It does work for both PAL and NTSC, and for 4:3 and 16:9, and takes into account the different pixel aspect ratios for these combinations.

If anyone wants to have a play, see if they can crash it, or show where it doesn't work, please feel free to download it here {URL removed - use the new one in the later posts} (at least until I find a new home for it). Just unzip to a new folder and run the exe.

Happy for any feedback or comments. It's not groundbreaking stuff, just a little something to ease the process.

[guns1inger]

Added VirtualDub expanded frame values to the display and tidied up the rounding of the final numbers (rounding only occurs at final output). It also now has a visual and numeric representation of the aspect ratio. It can be used to downsize HD footage as well.

A new version now in place which accommodates resolutions <1.33, such as 60 x 480.

[guns1inger]

Not bumping for the sake of it. I have re-written it in C++, so it is now a very modem friendly 14kb download, much more friendly on the desktop, and hopefully of use to some. The URL is slightly different, so grab it here
http://users.tpg.com.au/adslrotx/Apps/aviresizecalc.zip

Cheers.

[clickit]

problem with server ????

[guns1inger]

Problem with my typing - all good now

[ChrissyBoy]

Are you sure the computed values are correct? They seem to differ from: https://www.videohelp.com/guides.php?guideid=360#360

(unless i am using the tool wrong)

[guns1inger]

I hadn't read that before, however reading through it now it seems incomplete. It ignores that fact that avis generally have a 1:1 pixel aspect ratio, which is fine for PC display, but PAL and TSC display devices have non-square pixel apsect ratios, and these are different not just between formats, but also between fullscreen and widescreen. My calculator adjusts the resolutions so that when the converted files (now in DVD form) is played back on a TV, there is no distortion. The calculations I use are based on this table http://www.mir.com/DMG/aspect.html#reftable

I am happy to see evidence that my calculations are incorrect, but I would like to see the workings to prove it.

[fmctm1sw]

I've never been much on aspect ratios so let me make sure I understand this. I simply select my TV standard (NTSC) and desired aspect ratio (4:3). I put in the resolution I capture at (704x480) and presto. I'm supposed to encode at 720x446? But since I want to be DVD compliant, I have to add borders to this to get to 480? Very simple, if I understand correctly. It errored out when I tried a 16:9 AR though. What do I do if I want 16:9? I like it..

[guns1inger]

You have it right. The reason it didn't allow you to calculate 16:9 is that the video is too tall. To encode it as 16:9 would require reducing the horizontal resolution substantually. I am looking at incorporating calculations for this soon, but generally it is impractical or of little value to do this.