How long is my file?

[budgirl357]

How can I tell how long my movie is going to be after encoding? How do I tell whether I should split it in one, two, or three places? I'm sure that I have overlooked the answer to this question, I feel kind of silly asking. Thanks for the help!

Peace,
budgirl357

[AceYu]

Check out tools section assuming you are going to encode to
Mpg1 or 2 there are a couple of good calcs there

Later BRETT

[KingJohn]

How much data can you fit on the CD

[kitty]

BG - the newer versions of TMPGenc wizard give you an encoding estimate with a bar that shpws how much can fit a CD.

[Morheus]

Compliant VCD's are almost always 10mb per minute
Xvcd's can be turned out real small 6-7mb per minute (and by the way they can look just as good with lower than 800 bit rate "CBR" the problems is you can't loan those out to all your friends cause most DVD players will "Freak Out" (LOL)


hope this helps
Tony

[budgirl357]

Okay. Thanks for all of your replys. However, being that I am a major newbie, I need a little more clarification on this. Now, I wanted to know how long the movie was so that I could know whether to encode it for 2 or 3 cds. now, the resolution is low (like a vcd), but that doesn't mean that it can't be svcd does it? It claims to be dvd rip, so I figured that it was MPEG-2 (despite the res), so I am trying to make svcd out of it. so since the res is so low, I figured that it may be shorter than the average dvd rip with high (svcd) res - thats where the question came in.
You referred me to the bitrate calculator for exact help - only that seems too complicated. One of the first questions is "what is the length of your film?" That is what I want to know in the first place! I would like to know how to use the bitrate calculator, where can I go to find out what all those terms mean and how to find the info to calculate?

So the bottem line is, How can I find the length of the film still? The res is unusual for dvdrip (I think) and that is how I usually determine whats what. I hope that you can figure out my question. Don't talk about this post too bad! Hey, I am tired and I want to know the answer to this question...

Tired as hell 1 in the morning, still banging away on the computer - budgirl357

[AceYu]

Unfortunatly there are several variables that need to be taken into account when answering you question, most of which will be vauge answers but the following might help. Most Q's arn't silly so ask away

. Now, I wanted to know how long the movie was so that I could know whether to encode it for 2 or 3 cds.

Lenght in mins for the movie should be the same as the origional, an easy way to find this out is the propities box in Window media player or similar program. It should also tell you the codex/file format used, resolution etc. IF the file doesn't need re-encoding then look at the file size in windows explorer.

If however you are asking about min in relation to "80min" CD etc. It is better to look at Megabytes. CD-R/RW can be written to in a variety of ways, making the amount of data they can carry also variable. Normaly a 80 min data CD can hold 740MB, VCD and SVCD use less error correction etc than data CD so an 80min CD holds about 800MB. Therefor for example if the file is 1.4 Gig then it will fit across two disks (1.4 gig = 1400 MB (approx), 1400/800 < 2 therfore two disks)

This is where the second part comes into it, encoding bitrates, resolution etc. The main (only) determining factor to size is bitrate, which measured in is bits per second. Therefore if you use constant bit rate (CBR)encoding size is easy to determin, bits per seconds x number of seconds of movie = size of file (in bits), convert this to MB for conveniance. Using Variable bit rate (VBR) encoding uses a Target rate or min and max rates, making calculations harder, untill you encode you won't know the actual size. However some calculators /encoders will do an estimate for you, else you can guess but assuming the average bitrate will be correct and calculate from here as per CBR, if you allow about 10% extra you are generally safe (most of the time). It is then just a matter of dividing this by the size of you CD (800Mb for 80min CD) to give you the number of disks.

the resolution is low (like a vcd), but that doesn't mean that it can't be svcd does it? It claims to be dvd rip, so I figured that it was MPEG-2 (despite the res), so I am trying to make svcd out of it.

No it doesn't, any video resolution can be converted to any other, smaller to larger or back. This does not however mean it is a good idea!! (more on that in a bit). The fact it claims to be a DVD rip doesn't mean a lot, it could have been ripped as an MPG2, MPG1, DIVX, AVI .... or anything else. Check the format of the file as to what it actually is. The codex used is (mostly) independant to the resolution, some codex have limits on max and min resolutions or they must be a multiple of x pixels as in MPGS (8 in this case). Back to the res resizing thing. If your original file is the correct resolution and format to use as an VCD then DONT re-encode it to SVCD unless you have a VERY good reason (ie your player wont play VCDs) and vice versa. Any re-encoding, resizing, etc will in general result in a worst picture with minimal gain. If you need to, to get it into a correct format then go ahead.

so since the res is so low, I figured that it may be shorter than the average dvd rip with high (svcd) res - thats where the question came in.

As explained earlier bit-rate is the determining factor, assuming you are re-encoding. If it is already in the right format then you need a tool to cut it so it will fit across X disks.

where can I go to find out what all those terms mean and how to find the info to calculate?

See the How to's on this site or use the search function (thats how I started). They probably explain this a lot better than I have. Hope somthing makes sense

[budgirl357]

Yes, thatnk you so much. That was a very informative post. However, Like I said, I am a baby to all of this, so I am going to keep digging until I understand completely. Your information definatley got me closer to my goal. I just have never really loved math that much! I ended up using the TmPg calculations to determine how long to make the disks. It was a tool that I have been overlooking by bypassing the wizard, and I am glad that you brought it to my attention. some questions that have are:

What is the difference between cbr and vbr? I know what they stand for, but what do they mean and how should I apply this info to making better video results?

Also, a very basic one: what is the breakdown of megabytes in a gig, etc? You know, like the table that was in my junior high math book that explained grams, ounces, pounds...well, what about a conversion chart for digital "measurements"?

Im sure that I can think of a million more. I come up with new ones every day! I again thank you for the help, and I may probobly be able to keep you busy with more questions in the future, if you don't mind. I like your style!

Well, I have completed the encoding for oceans eleven and now I am workingon LOTR. Thanks to you, I wont have to do so much guessing this time around.

Peace (until next time)

budgirl357

[AceYu]

What is the difference between cbr and vbr? I know what they stand for, but what do they mean and how should I apply this info to making better video results?

CBR = Constant bit rate, the bit rate is the same throught out the disk.
Makes size calcs easy but compression wise there may be lots of wasted space (redundant info that could have been compressed). Compression is faster but quality may suffer as an overall lower bitrate may be needed due to size constraints.

VBR = Variable bit rate, the bit rate varies from frame to frame depending on the amount of "detail", movement and changes from the previous frame in the current frame. Better compression as scenes with very low movement /changes need less info to record, however due to the nature of VBR compression takes (in theroy at least) longer as most VBR uses a 2 pass or more technique. Bit rate calcualtions are harder as only Min/Max bit rates can be set with any accuracy and target bit rates are only that. Quality can be better if the max bit rate is set higher than it otherwise might be in CBR.

some other points. If you use VBR and set min and max bit rates you are effecivly using CBR. If the MAX bitrate in VBR is less than CBR it will ALWAYS look worse. If the Min bit rate for VBR is set higher than CBR then it will always be bigger. (obvious but you know).

Also, a very basic one: what is the breakdown of megabytes in a gig, etc? You know, like the table that was in my junior high math book that explained grams, ounces, pounds...well, what about a conversion chart for digital "measurements"?

bit = 1 well bit
Byte = 8 bits, Important as many things are quoted as bits per second (bps), NOT Bytes per second,also noted as Bps although the capital should denote byte but it often doesn't. to convert bytes to bits mulitply by 8.

Kb/KB = Kilobits/bytes/ (again check context varies) = 1024 bits/bytes
the use of 1024 Vs 1000 is due to 1024 being a power of 2 (2^11)
this is Always 1024
Mb = 1024 kb = 2^13 = 1048576 bits/bytes

Gb = either 1000 or 1024 Mb this varies depending who you talk to, many things are quoted as X gig and use 1000 to calculate this as it appears to be larger (to the general public). Also when looking at hard drives often you will see drives listed as say 40 gig but you can only store say 38 gig (figures are not accurate) this is because it is 40 gig unformatted and the formatting info so the OS can read it is using the other 2 gig.

Any more???
Later BRETT