hybridgain question

[filewalker]

Hi,
I read the faq's and searched the forum for hybrid gain but I only found that it's similiar to the "Post gain" in BeS. 1.4.
I generally used "Post gain", "Auto find Max. gain" and " Use dialog normalizition reduction" in BeSweet 1.4. for getting Ogg Audio.
I liked the results because:
DSPguru:
1)postgain is a method were gain is being asserted after processing the signal (eg, encode to mp3 and find the maximal gain at the same time, then raise up the volume by modyfing the global_gain).
One last final advantage of post-gain is that you can guarantee that with post-gain applied, you can absolutely guarantee that the decoded playback will not clip and will have the highest volume possible (within 1.5dB).
2)Dialog normalization is used to force different ac3 tracks to have the same playback loudness.

Do i get these two results with hybrid gain in BeSweet 1.5b10,too.
Does it mean that " Use dialog normalizition reduction" is automatically done with hybrid gain?
What is the difference between my 3 settings(mentioned above) in BeS 1.4 on the one hand and hybrid gain in BeS. 1.5b10 on the other hand.



Cu filewalker

[DSPguru]

hybridgain is the way to go.
BeSweetGUI, read the tooltip for more info.

[JohnMK]

Originally posted by filewalker
One last final advantage of post-gain is that you can guarantee that with post-gain applied, you can absolutely guarantee that the decoded playback will not clip

From my own testing, this isn't the case; DSPGuru acknowledged that much. Hybrid gain clips, it's just not extreme and probably not noticeable unless you have exceptional ears. If you care about it not clipping at all, then use the 'BeSafe' commandline program.

[DSPguru]

BeSafe will keep you safe, but hybridgain had been tuned to assert 97% of max postgain, and i believe JMK was the one that helped me picking this value :).

[filewalker]

Thank you for your replies and answers!

I read the tooltip and I'm theoretical satisfied how hybridgain(3 different methods for Ogg Audio) works!
If i understood your past discussion (http://forum.doom9.org/showthread.php?threadid=37557&highlight=post+gain) correctly, DSPguru set the gain value from 98% to 97% for reaching a "Not-clipping".
I'll use hybrid gain and only when I'm, against the expections, not satisfied with hybrid gain(because of clipping) I'll also become a Mr. paranoid :D :D ;) and would use BeSafe.

But, nevertheless, I expect a great deal of hybrid gain!

Cu filewalker

[JohnMK]

Originally posted by DSPguru
BeSafe will keep you safe, but hybridgain had been tuned to assert 97% of max postgain

So BeSafe is no longer required?

[DSPguru]

it's useful for paranoids :D.

[iago]

@DSPguru

This might be a silly question but in BeSweetv1.510b (with BeSweet GUI v0.6 b66), when going for 2.0 AC3 -> Ogg Vorbis using "HybridGain" in the BeSweet menu, should I uncheck everything in the Azid 1 menu ("LFE To LR Channels", "Dynamic Compression", "Gain") which are automatically activated when choosing "DSPguru_OGG@90kbps" profile?

regards,
iago


What I've been doing so far (with 2.0 AC3 -> Ogg when using "HybridGain") is only unchecking the "LFE To LR Channels" and "Gain" and keeping the "Dynamic Compression" ticked in Azid 1 tab.

[DSPguru]

hybridgain only affects :
Azid - Dialog Normalization & Gain
Ota - PostGain
Lame - scale

anything else like dynamic compression or LFEtoLR still has its original meaning. if you used to use them, you should continue.

[iago]

@DSPguru,

Thanks for the reply. Well, using OggMachinev0.6 is another and even simpler way of course! ;)

regards,
iago

[raistlin2k]

just a question: why do you use postgain 0.97 instead of 1 in hybridgain?
I mean if clipping occurs due to pre-gain of 10dB it won't help anything to reduce post-gain?!?

Just had a movie clipping with hybridgain (THE ROCK), because I have forgotten to set compression to normal.

ANYWAY, I tried to use -azid( -g 10db -n 1 ) -ota( -G 1 ), which should be the same as hybridgain with postgain 1, no?

Result: In both cases, postgain applied a negative gain, difference was just the value between postgain 0.97 & 1.

So WHY Postgain 0.97 in Hybridgain instead of 1?

Thanks
Raist

[DSPguru]

http://forum.doom9.org/showthread.php?threadid=37557