File resolution!!!

[maxiox]

Hi guys,
I would like to know if when encoding a film, resolutions like 720*350 or 750*520 makes different file sizes. I think yes, but if so, why does rate calculators don't consider the file resolution when calculating the data rate???

Please tell me a rate calculator that consider this option if it exists!!!

THANKS!!!

[Enchanter]

It shouldn't, but it seems to do that when doing 2-pass encoding, for some obvious reasons.

That aside, resolution does not really matter wholly to the movie as bitrate does. Say, 2 same movies with the same filesize, but different resolutions are played together. The bigger-resolution movie will, somehow, look more dull than its lower-resolution brother. This is because each 'blocks' (Can't remember the correct term) on the latter gets more bits and hence can look sharper.

No one calculator can precidely predict that, as the bitrate graph is different for each movie. But yiou can always use your gut feelings.

[UncasMS]

for one pass solutions a bigger res automatically means bigger filesize!

tools like nandub, however, let you determine the final output size and STICK TO IT PRECISELY (using ms v2/divx3 that is, divx4/5 are not as precise!!)

[Ndb]

I really can't understand how a bigger res can give a bigger files size.

If I encode a movie at 640 x 480 at 1000 bitrate and a 800x600 movie at 1000 bitrate I'm still only using 1000 bits. I just get the same file size, but the 800x600 movie has make the 1000 bits spread more than the 640x480 one and I get worse picture quality with the 800 one.

It's only with VBR that you get any real difference as the 640 one could use less on low motion scenes than the 800.

I've done it with the low motion 3.11 and 1-pass quality mode a bit and the movie size does not seem to change much regardless of Res.

But then again it maybe that I'm just lucky

[UncasMS]

using mpeg2avi filesize differed, though 1000kbps should be 1000kbps no matter what res one uses.