Question regarding bitrate calculator

[noaht1980]

Thisis my 1st time trying a bitrate calculator for my encoding cause i have always used CQ for encoding well anyways i downloaded FitCD

I entered the following info

Time of movie = 52 mins 20 secs
FPS = us dvd so should be 23.976 right?
Amount of CD's = 1

And it gave me the information as you can see in the screenshot but what i dont understand is it sayd 3 differant bitrates

Min = 1149
Max = 2521
Kbps video = 1869

So what i am wondering is when i load the NTSC template in TMPGEnc and goto put my min and max bitrate do i just use these
Min = 1149
Max = 2521

if so whats the Kbps video = 1869 mean?

Sorry but im a little confused

[poopyhead]

2 pass VBR requires min, max, and avg. bitrate.

Kbps video = 1869

this is most likely the avg. bitrate.

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however, if i were you, i would lower the min bitrate you enter to like maybe 300 kbit/s.

Min = 1149 is too high for a min bitrate. there are many scenes (i.e. end credits) that don't require such a high bitrate.

[noaht1980]

Thanx

I wont be doing a 2 pass VBR cause i only have 600mhz computer so i will be doing just a CBR so do you think i should do as follows for a 52 min FS movie

Min = 300
Avg = 1869
Max = 2521

Does that sound ok?

Will that fill a 700mb CD so basically like 795MB

By the way its a cartoon movie in case that makes any differance

[poopyhead]

CBR allocates the exact (or nearly) bitrate for every scene...there will be max or min...only "bitrate"...and that's it. there's no range of bitrate for the encoder to apply because it will apply a Constant Bitrate to every scene.

this bitrate will be the avg. bitrate you just mentioned. however, because the bitrate is slow low (i.e. < 2 mbit/s) i would suggest you at least use CQ VBR. you can set a min and max bitrate. there is no avg. bitrate for CQ, but there is a CQ setting. i would advise you to set that to 70. this form of VBR is much faster at encoding... similar to CBR. however, because you specify a min and max, the encoder will be able to allocate the extremeley precious bitrate much better.

warning: CQ VBR does not have predictable filesize. since there's no avg. bitrate, you can't really predict the final filesize. it's basically a trial-and-error. however, there are CQ filesize prediction proggies out there. just do a search for them...however, they're not as reliable as would be for 2 pass VBR.

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theory behind why you wanna use VBR, instead of CBR...especially if you use lower bitrates. CBR allocates the exact same bitrate to each scene. this means that the end credits (just scrolling text) will be given the same bitrate as a fast action scene. obviously, the former requires less bitrate than the latter. what VBR does is to take some of the unneeded bitrate from slower scenes and gives them to fast action scenes. the slower scenes won't suffer very much in quality because they don't need that much bitrate to begin with. however, fast action scenes require a lot of bitrate, so giving those scenes more bitrate will dramatically affect video quality.

[noaht1980]

Ok i will use a CQ value of 70 as suggested on this 52 minute christmas cartoon movie and i will just hope that it comes out at or about 800MB