pulldowned m2v file smaller than original?

[HOLiC]

Hi, I'm using DVDmaestro.
And after few hours of searching and reading,
I finally managed to solve subtitle's synch problem.

Question is..
after running m2v file thru pulldown.exe (-nopulldown -drop_frame true/my dvd is -ntsc ),
the output file is smaller than the original m2v file, is this ok?

For instance..
original m2v = 1,939,900, after pulldown m2v = 1,939,489.
Not much difference.. and subtitles are perfect in synch, and no problem with video or audio at all!
But why the difference in size?
Last time I worked with different dvd, the size of m2v files were the same even after I did the pulldown.

I'm just curious, and want to know if it's ok to just ignore this difference...
Thanks in advance!!

[Guest]

Unless you provide the files (or ending fragments thereof) we can only guess. Maybe they handle sequence end codes differently or something like that. Maybe one is deleting user data. Who knows? It's a small difference; I wouldn't worry. If you want to give us the ending fragments, perhaps we can see the reason.

[HOLiC]

hmm.. so size shouldn't change at all? Even after the pulldown, right?

Yes, although I see no harm with this small difference, not knowing "why" is really annoying.
When you say ending fragments, do you mean the last part (like cut 20mb or bigger?) of
pulldowned and original m2v file?

Anyway, I made d2v files from these two files (hehe, I pretty much did everything I can
think of in order to understand this problem...T.T), and the difference were:

DVD: RC2 Aria the animation/ NTSC interlaced

From d2v file of orginal m2v file = 2,682,761


Stream_Type=0
MPEG_Type=2
iDCT_Algorithm=5
YUVRGB_Scale=1
Luminance_Filter=0,0
Clipping=0,0,0,0
Aspect_Ratio=4:3
Picture_Size=720x480
Field_Operation=0
Frame_Rate=29970 (30000/1001)
Location=0,0,0,1477C4

end:
d00 1 0 2746230340 0 0 b2 b2 92 b2 b2 a2 b2 b2 a2 b2 b2 a2 b2 b2 a2
d00 1 0 2746673924 0 0 b2 b2 92 b2 b2 a2 b2 b2 a2 b2 b2 a2 b2 b2 a2
d00 1 0 2746691928 0 0 b2 92 b2 a2 b2 a2 b2 a2 b2 a2 b2 a2 b2 a2 a2 ff

From d2v file of pulldowned m2v file = 2,682,317
(-nopulldown -drop frame true)


Stream_Type=0
MPEG_Type=2
iDCT_Algorithm=5
YUVRGB_Scale=1
Luminance_Filter=0,0
Clipping=0,0,0,0
Aspect_Ratio=4:3
Picture_Size=720x480
Field_Operation=0
Frame_Rate=29970 (30000/1001)
Location=0,0,0,1476E6

end:
d00 1 0 2745757164 0 0 b2 b2 92 b2 b2 a2 b2 b2 a2 b2 b2 a2 b2 b2 a2
d00 1 0 2746230340 0 0 b2 b2 92 b2 b2 a2 b2 b2 a2 b2 b2 a2 b2 b2 a2
d00 1 0 2746673924 0 0 b2 b2 92 b2 b2 a2 b2 b2 a2 b2 b2 a2 b2 b2 a2 ff


It seems like pulldowned m2v file stop at 2746673924/with ff while the original m2v
file has up to 2746691928/with ff...

Not that I understand any of this.. lol
Ahh, it does seems like the difference in size is due to difference in ending sequence or something..
IF i'm right, what is the cause? and how do i fix it? or is this just a random thing that I can ignore?
IF i'm wrong.. I'llupload whatever you need..

And thank you, neuron2!! (_ _)

[Guest]

hmm.. so size shouldn't change at all? Even after the pulldown, right? Right.

When you say ending fragments, do you mean the last part (like cut 20mb or bigger?) of
pulldowned and original m2v file? Yes.

Ideally, duplicate it with a small M2V, such as 50MBytes. Then upload the two complete files for me to download.

Also try it with DGPulldown.

[HOLiC]

Oh my.. I tried DGpulldown and the output file size is the same as the input m2v file! But I wonder why pulldown.exe would give me a different file size? Here's the link anyway:

last fragment of original m2v file:
http://rapidshare.de/files/22827426/Original123.rar.html

last fragment of m2v file that went thru pulldown.exe:
http://rapidshare.de/files/22829055/Pulldown123.rar.html

Thank you!!

[Guest]

Here is why it is happening...

Your original file has two sequence end codes! There is one near the end of the file and one at the very end of the file. Apparently, pulldown.exe stops at the first one. The last two frames are in the section after the first sequence end code, so pulldown.exe is losing you two frames at the end. They are black frames.

You might want to investigate why there is an extra sequence of two black frames appended after the first sequence end code. A sequence end code is an MPEG2 start code with this value: 00 00 01 B7. Normally, it signals the end of an MPEG2 stream.

I believe tools exist to remove sequence end codes (usually they are not needed), but why bother when you can use DGPulldown? That will leave the black frames intact, however. Letting pulldown.exe truncate them may cause audio sync problems. It's better to find out why the sequence is there and get rid of it properly along with any corresponding audio (if any).

[HOLiC]

Thank you very much Neuron2!!
I coudn't figure out exactly why my original file has two sequence end codes.. But when I looked at the source/dvd's VTS_01_0. IFO with ifoedit/vobblank.. it seems like the last chapter that is only 00:00:00:15 long, was the problem. This last part is V/C ID 13 which is also used by every other pgc in the movie.. or perhaps something else, hehe

Anyway, I used DGpulldown and then used Restream to remove the end code from the m2v file. And everything turned out to be great!! Subtitles are in synch and chapters are perfect! Thanks again for your help!!

[Guest]

Hmm. Maybe DGPulldown should have an option to suppress sequence end codes. Then you could avoid one additional step.