(s)vcd bitrate calculation formula

[[L]egion]

I was hoping someone could tell me the formula for calculating an avg bitrate for time for an SVCD and VCD. I know there are calculators that will do this but I want to know the formula.

[dick_p_t]

with the formula, you first need to work out how big the storage media is in KB

I work it out as
74min CD-R = 762570KB
80min CD-R = 803790KB
99min CD-R = 999585KB

then multiply by the ammout of media you are going to use (how many CD-R)
totalkb = mediakb * media_ammount

Then work out the bitrate by

bitrate = (totalkb / movie_length_in_seconds) * 8

this bitrate is for the audio and video so what you need to do is take out the audio bitrate that you want to use.

IF audiobitrate = 224 then
videobitrate = bitrate - 224

Hope this answers your question.

Rob

[Digifreak]

File Size(megabytes)*8000(kilobits/megabyte)=[Audio Bitrate(kilobits per second) + Video Bitrate(kilobits per second)] x File Length(seconds)

If you're burning VCD or SVCD you can set file size to around 800-805MB to fit a 700MB(80min) disc. Use algebra to extract the variable you are after.

[[L]egion]

Ok yah that works great. Dick_p_t how exactly did you calculate the 800 MBs into the 803790 KBs? Arent you supposed to do 800x1024 which would equal 819200 KBs

[dick_p_t]

i worked it out like this;

80 min cd holds 78 mins of mpeg data comftobaly

78 * 60 = 4680

video
4680 sec * (1150/8) = 672750

audio
4680 sec = (224/8) = 131040

672750 + 131040 = 803790