Matrices loading in bbMPEG step

[herineth]

Hi All,

sorry for kinda cross-posting this (*sigh* now its a real cross-post did post this in newbies, need some sleep), but in the newbies forum nobody seems to know the answer to my original problem/quest.

Short: How can i force automatic loading of my matrices in the bbmpeg step. If not there may be the need of a feature.

Please see also

http://forum.doom9.org/showthread.php?s=&postid=71556

for feature request/details.

best
herineth

[dvd2svcd]

bbMPEG is only being used as a muxer. It does not encode, therefore there is no need for that.

[waldok]

Hi,

If you want to insert your own matrices in the header at muxing step, you have to use the mpv and mpa files produced from DVD2SVCD and mux them yourslef using bbmpeg.

OPen bbmpeg, click Start Encoding, click Settings and go to the input/output tab.

Locate the matrices file .mat you need and open them with OPen IQM (Intra Quant matrix) and OPen NIQM (Non intra).

Then mux the whole stuff
Hope this helps.

Waldok:cool:

[herineth]

HI,

[dvd2svcd]
> bbMPEG is only being used as a muxer. It does not encode, therefore
> there is no need for that.

Yes, but when I patched the CCE with my matrices it does not write back the matrices to the mpv stream. At least I read that in context to the patcher. So If this is true I havt to feed them to bbmpeg if I want to do it all properly.

[waldok]
Yeah, I did so when I did all by hand. Just downloaded DVD2SVCD and hoped it does this automatically. It looks like that I'm at the point of doing it by hand again

best
herineth

[waldok]

Sorry I didn't know you already did by hand. But yes, you'll have to do it again I'm afraid (not a big deal though):)

Waldok:cool:

[herineth]

Hi Waldok

Originally posted by waldok
Sorry I didn't know you already did by hand. But yes, you'll have to do it again I'm afraid (not a big deal though):)


You don't have to excuse, I'm still a newbie in this field with my two month of experience :)

So as this might be also interesting for others here my feature request to dvd2svcd:

Nice would be to have a button in the bbMPEG tab that opens a dialog with input fields to load the matrices for a project (and/or to set the default matrices). Or something similar.

Best,
Herineth

[duronator]

Could you please explain this to me? I use the Very Low Bitrate-matrix in CCE. Is it then necessary to load the same matrix into BBmpeg before multiplexing?

Does this really make a visual difference?

[herineth]

Could you please explain this to me? I use the Very Low Bitrate-matrix in CCE. Is it then necessary to load the same matrix into BBmpeg before multiplexing?

If the patched CCE really does not write them back to the stream I'd say yes.


Does this really make a visual difference?

I don't know. I can only repead what I've read. The matrices are storen in the mpeg header and the DVD player uses them for decosing the mpeg stream. So they are decoded with excatly the same patterns as you encoded it. I guess the player just uses a default matrice if they are not present in the stream.

So I assume decoding the stream with the very same matrices used for encoding should at least give playback the stream with the quality the stream is encoded at.

Anyway I'm absolutely uncertain about this. I read this in the/a forum. I'll try to find the source tomorrow.

Best,
Herineth

[duronator]

herineth:
I did a little test. Patching CCE to use a different matrix then the standard one *does* result in a different mpv-stream.

Selecting a different in BBmpeg before multiplexing does *not* change anything in the resulting mpg-file.

I checked this using a hex-compare tool so I'm certain about this. It seems that it is no use to load a matrix in BBmpeg.

I used a small PAL-DVD sample to test this.

[Mozart]

yes, duronator. You are right. There is no information about "add matrix head while muxing" in bbmpeg documentation. Could somebody ask for Brent Beyeler opinion?

[herineth]

Hi guys,

here's the thread where I read about the matrix thing.

http://forum.doom9.org/showthread.php?s=&threadid=14691


duronator:
Cool. So it means there is no need to feed them to bbMPEG. Hmm the other thread recommends that.

Yeah, mabye someone should as Brent, so that we're certain about it.

G'nite
herineth