#193 Bits/(Pixel*frame) calc incorrect for "Calc AVI Filesize".


When using the "Calculate AVI Filesize" mode in Gordian
Knot 0.32.0 beta, the Bits/(Pixel*frame) calculation is
incorrect. Gordian Knot takes the video's average
bitrate entered and converts it to bits/sec by
multiplying it by 1024 instead of 1000. (The
"Calculate Average Bitrate" mode in GK seems to use
1000 for the kilobytes to bytes conversion btw...)

"Calculate AVI Filesize" mode example:
If the Average Bitrate entered is 500, the movie's
length is 6789 seconds and the framesize is 320x120
with 200000 frames, Gordian Knot does the math as
follows to calculate the Bits/(Pixel*frame):
((500*1024)*6789)/(320*120*200000) = ~0.453.

The calculation should be (I think...)
((500*1000)*6789)/(320*120*200000) = ~0.442.

The problem can be shown by switching between the
"Calculate Average Bitrate" and "Calculate AVI
Filesize" modes... The Bits/(Pixel*frame) calculation
will switch between the two values.

If you have further questions, please contact me.
btw, I really enjoy your product!
-Dan G.
(remove the three "X"'s in my email addr to contact me).


  • Tony Lenox

    Tony Lenox - 2004-09-14
    • status: open --> closed-invalid
  • Tony Lenox

    Tony Lenox - 2004-09-14

    Logged In: YES

    Nice observation, but its not a bug. When you say to
    calculate bitrate then you see approximate value as its being
    rounded (say ~500kbps). Then when you switch to calculate
    size you set it to 500 sharp! That means that final size will
    change as well (you can see that), so bpp value is slightly
    different as well.


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