slightly undersized files

[tolkien]

i converted about 5 music videos to xvid last nite and theyre a bit undersized.. ranging from about 1-3 mb :sly:

2 of em ran for 3:28 and i specified a size of 69 mb and both of em came back at exactly 67.6 :scared:

is undersizing by a few mb normal? :helpful:

[CWR03]

is undersizing by a few mb normal?
Probably, but since you didn't list the procedures used to create these files, there's no way to tell.

Do you just click a random smiley for the end of each sentence?

[tolkien]

what sort of procedures should i list? like what settings i used?

no i briefly thought about which smilie to use :stupid:

[manono]

Hi-

Since this is the forum for both Gordian Knot and Auto Gordian Knot, you could start by telling us which you used. A log file for the encode might help as well.

To answer the question, ordinarily, for a full movie, you should probably come within a couple of hundred KB of the desired size. So, being 1-3 MB off on a 69 MB encode is too much.

[DarkZell666]

So, being 1-3 MB off on a 69 MB encode is too much.Except if he set his min quants to 2 and the whole clip got encoded @ quant 2. I frequently encode anime episodes targeted at 175MB which come out at 155-160MB because of that :) (the quality is perfect though :p)

Edit: Another explanation I would investigate :

Be careful about the 1024/1000bits per kB calculation.

I've just noticed that 1000/1024 = 0,9765625
and that 67.6/69 = 0,97971... they're only 0.003 apart.

Which would mean that the other clips are in fact a bit oversized because they're not compressible enough, which is more believable than my first statement, imho. Music video's are rarely compressible =)

[tolkien]

oh ok well i used autogk

my sources were pal hdtv mpeg2 at 1280x720 50 fps but the video had big borders on the left and right.. so its like a 4:3 video in a 16:9 frame i think

what i was doing was changing the resolution to 720x528 and reducing the fps to 25 fps and change audio to 160kbit mp3

in the advanced options its mostly default except i checked override input ar and checked original and i also checked use sharpmatrix

[jggimi]

:logfile:

[tolkien]

[13/12/2006 3:58:46 AM] AutoGK 2.27
[13/12/2006 3:58:46 AM] OS: WinXP (5.1.2600).2
[13/12/2006 3:58:46 AM] Job started.
[13/12/2006 3:58:46 AM] Input file: D:\WinFast WorkArea\Fergie_-_London_Bridge_HDTV_720P-TLK.mpg
[13/12/2006 3:58:46 AM] Output file: D:\WinFast WorkArea\Fergie_-_London_Bridge_HDTV_720P-TLK.avi
[13/12/2006 3:58:46 AM] Output codec: XviD
[13/12/2006 3:58:46 AM] Audio 1: Audio Stream 0 AC3
[13/12/2006 3:58:46 AM] Subtitles: none
[13/12/2006 3:58:46 AM] Format: .AVI
[13/12/2006 3:58:46 AM] Target size: 69Mb
[13/12/2006 3:58:46 AM] Custom resolution settings: fixed width of 720 pixels
[13/12/2006 3:58:46 AM] Custom audio settings: CBR MP3 with bitrate: 160Kbps
[13/12/2006 3:58:46 AM] Started encoding.
[13/12/2006 3:58:46 AM] Demuxing and indexing.
[13/12/2006 3:58:51 AM] Processing file: D:\WinFast WorkArea\Fergie_-_London_Bridge_HDTV_720P-TLK.mpg
[13/12/2006 3:58:51 AM] Source resolution: 1280x720
[13/12/2006 3:58:51 AM] Found PAL source.
[13/12/2006 3:58:51 AM] Source aspect ratio: 16:9
[13/12/2006 3:58:51 AM] Manual aspect ratio: Original
[13/12/2006 3:58:51 AM] Loading custom fps file.
[13/12/2006 3:58:51 AM] Output will contain 5208 frames
[13/12/2006 3:58:51 AM] Decoding audio.
[13/12/2006 3:58:56 AM] Normalizing audio.
[13/12/2006 3:58:57 AM] Encoding audio.
[13/12/2006 3:59:26 AM] Forcing encoding with sharp matrix.
[13/12/2006 3:59:26 AM] Picking up autocrop parameters.
[13/12/2006 3:59:26 AM] Audio1 size: 4,162,080 bytes (3.97 Mb)
[13/12/2006 3:59:26 AM] Overhead: 61,824 bytes (0.06 Mb)
[13/12/2006 3:59:26 AM] Video size: 68,127,840 bytes (64.97 Mb)
[13/12/2006 3:59:26 AM] Running compressibility test.
[13/12/2006 3:59:26 AM] Writing the following script to D:\WinFast WorkArea\agk_tmp\Fergie_-_London_Bridge_HDTV_720P-TLK_comptest.avs
===========================================================
LoadPlugin("C:\ALLFRO~1\VIDEOE~1\AutoGK\DGMPGDec\DGDecode.dll")
LoadPlugin("C:\ALLFRO~1\VIDEOE~1\AutoGK\filters\autocrop.dll")
LoadPlugin("C:\ALLFRO~1\VIDEOE~1\AutoGK\filters\RemoveGrain.dll")
LoadPlugin("C:\ALLFRO~1\VIDEOE~1\AutoGK\filters\fdecimate.dll")

movie = mpeg2source("D:\WinFast WorkArea\agk_tmp\Fergie_-_London_Bridge_HDTV_720P-TLK.d2v")
movie = FDecimate(movie,rate=25,threshold=1)
cropclip = autocrop(movie,mode=0,wmultof=4,hmultof=4,samples=10,aspect=0,threshold=34,samplestartframe=0,leftadd=0,rightadd=0,topadd=0,bottomadd=0)
fixed_aspect = 1
c_width = width(cropclip)
c_height = round(height(cropclip) / fixed_aspect)
input_par = float(c_width)/float(c_height)
out_width = 720
out_height = round(float(out_width) / input_par)
hmod = out_height - (floor(out_height / 16 ) * 16)
out_height = (hmod > 4) ? (out_height + (16 - hmod)) : (out_height - hmod)
new_aspect = (float(out_width) / float(out_height)) / fixed_aspect
autocrop(movie,mode=0,wmultof=4,hmultof=4,samples=10,aspect=new_aspect,threshold=34,samplestartframe=0,leftadd=0,rightadd=0,topadd=0,bottomadd=0)
LanczosResize(out_width,out_height)
RemoveGrain(mode=2)
SelectRangeEvery(38,15)
===========================================================
[13/12/2006 4:03:50 AM] Duration was: 4 minutes 24 seconds
[13/12/2006 4:03:50 AM] Speed was: 7.69 fps.
[13/12/2006 4:03:50 AM] Compressibility percentage is: 52.31
[13/12/2006 4:03:50 AM] Using softer resizer.
[13/12/2006 4:03:50 AM] Chosen resolution is: 720x528 ( AR: 1.36 )
[13/12/2006 4:03:50 AM] Predicted comptest value is: 54.26%
[13/12/2006 4:03:50 AM] Running first pass.
[13/12/2006 4:03:50 AM] Writing the following script to D:\WinFast WorkArea\agk_tmp\Fergie_-_London_Bridge_HDTV_720P-TLK_movie.avs
===========================================================
LoadPlugin("C:\ALLFRO~1\VIDEOE~1\AutoGK\DGMPGDec\DGDecode.dll")
LoadPlugin("C:\ALLFRO~1\VIDEOE~1\AutoGK\filters\autocrop.dll")
LoadPlugin("C:\ALLFRO~1\VIDEOE~1\AutoGK\filters\RemoveGrain.dll")
LoadPlugin("C:\ALLFRO~1\VIDEOE~1\AutoGK\filters\fdecimate.dll")

movie = mpeg2source("D:\WinFast WorkArea\agk_tmp\Fergie_-_London_Bridge_HDTV_720P-TLK.d2v")
movie = FDecimate(movie,rate=25,threshold=1)
cropclip = autocrop(movie,mode=0,wmultof=4,hmultof=4,samples=10,aspect=0,threshold=34,samplestartframe=0,leftadd=0,rightadd=0,topadd=0,bottomadd=0)
fixed_aspect = 1
c_width = width(cropclip)
c_height = round(height(cropclip) / fixed_aspect)
input_par = float(c_width)/float(c_height)
out_width = 720
out_height = round(float(out_width) / input_par)
hmod = out_height - (floor(out_height / 16 ) * 16)
out_height = (hmod > 4) ? (out_height + (16 - hmod)) : (out_height - hmod)
new_aspect = (float(out_width) / float(out_height)) / fixed_aspect
autocrop(movie,mode=0,wmultof=4,hmultof=4,samples=10,aspect=new_aspect,threshold=34,samplestartframe=0,leftadd=0,rightadd=0,topadd=0,bottomadd=0)
BicubicResize(out_width,out_height,0,0.5)
RemoveGrain(mode=2)
===========================================================
[13/12/2006 4:10:26 AM] Duration was: 6 minutes 35 seconds
[13/12/2006 4:10:26 AM] Speed was: 13.16 fps.
[13/12/2006 4:10:26 AM] Expected quality of first pass size: 50.99%
[13/12/2006 4:10:26 AM] Running second pass.
[13/12/2006 4:19:45 AM] Duration was: 9 minutes 18 seconds
[13/12/2006 4:19:45 AM] Speed was: 9.32 fps.
[13/12/2006 4:19:45 AM] Job finished. Total time: 20 minutes 59 seconds

[tolkien]

pls..

[manono]

Sorry. I was hoping that someone else would jump in with something clever to say about it. The log looks fine to me:
[13/12/2006 3:59:26 AM] Audio1 size: 4,162,080 bytes (3.97 Mb)
[13/12/2006 3:59:26 AM] Overhead: 61,824 bytes (0.06 Mb)
[13/12/2006 3:59:26 AM] Video size: 68,127,840 bytes (64.97 Mb)

You got audio of that size, and it's the video that's maybe 2-3 MB undersized?

If there's a pattern to the undersizing (about the same amount undersized for encodes of a certain size), then you can allow for it by asking for an oversized result. If the results are undersized by seemingly random amounts, then I don't guess there's much you can do about it. Sorry, not much help.

[len0x]

There was a very valid point by DarkZell666 about Mb sizing. What is the exact size in bytes of the output ?

[tolkien]

i just wanna get the right size

[CWR03]

i just wanna get the right size
It may not be possible, especially if you don't give more information as to what you've tried. It rarely hits the specified size dead-on. Why are you even making such a big deal of a couple MB undersize anyway?

[DarkZell666]

i just wanna get the right sizeHave you at least read half of the info given in the whole thread ? :/

Hint: right-click > properties on the avi file GK created, and read the highlighted info:

http://xss.xas.free.fr/tolkien_gotcha.png

This will answer len0x's question (octets = bytes in french ^^)

The cause seems pretty wierd, so you'll have to try wierd things to find the problem. That's video encoding for you :p