What does "normalize" do in TMPGEnc?

[nocarebear]

I want to DVD-->CVD. The DVD audio is pretty low, so I want increase the volume by raising it to probably 150%, but I don't know what "normalize" is used for. Do I need to use it at all? The manual isn't helpful at all. It just says, "Normalization brings the volumes to a similar intensity. Normally, 75% is a reasonable value." I have no idea what this means.

[redwudz]

This from www.gromkov.com/tutorials/AVI2VCDTMPG.html ,

"Audio Effects: The main point of this is to make video that has low sound volume louder. It does this by normalizing the wave file before it converts it to MP2. Normalizing, is a way of amplifying audio to go as loud as possible without 'clipping' off the scale and causing corrupted parts. I'd say always use a normalization of 90-100%; I always use 100. They've also thrown in the option to fade in and out at the start and end of the movie which is more useful for small video clips that tend to end suddenly."

Hope this helps.

[nocarebear]

This from www.gromkov.com/tutorials/AVI2VCDTMPG.html ,

"Audio Effects: The main point of this is to make video that has low sound volume louder. It does this by normalizing the wave file before it converts it to MP2. Normalizing, is a way of amplifying audio to go as loud as possible without 'clipping' off the scale and causing corrupted parts. I'd say always use a normalization of 90-100%; I always use 100. They've also thrown in the option to fade in and out at the start and end of the movie which is more useful for small video clips that tend to end suddenly."

Hope this helps.

I noticed that the percentage I put into the normalize setting is the volume control. Does this mean that I don't have to adjust the actual volume control but only the nomalize percentage? And what is "clipping"?

[redwudz]

Not sure about the volume control part, but I would assume the audio is set to a maximum determined by the format? Anyway 'clipping' is when the audio signal is driven to a point of distortion, over 100%. This 'clips' off the top of the audio waveform and causes distortion and a decrease of dynamic range; not a good thing.

There can also be a problem if the audio is 'over normalized' where the dynamic range of the audio is decreased. That is where the loud and quiet parts of the audio are too close together in level. I wouldn't worry much about this, if you really need to increase the audio level, you will have to live with it.

Sorry, I'm not an expert in this. You might try some trial encodes with a short section of your file and see how it works.

[johns0]

100% volume in tmpgenc is where you present volume is at,if you are encoding a movie file with a wav that used to be ac3 then the sound will need to be raised about 20db to be brought up to normal levels if its going to be in a vcd or svcd so the volume is raised to about 175% to bring it up to about 0db.This is just an example.

[nocarebear]

I think I'm starting to understand it. I set the normalize to 75% and it adjusted the volume to 198.8% and it was certainly louder. However, even at normalize at 75%, the adjusted volume setting almost twice as loud. As that alright/normal?

[johns0]

uh....no,if you adjust it to 75% you get less sound,3/4 of the original sound,you set the normalize to 190% to get 95% increase in sound.

[johns0]

Do a test clip at 100% and see the sound difference,there wont be any.

[nocarebear]

uh....no,if you adjust it to 75% you get less sound,3/4 of the original sound,you set the normalize to 190% to get 95% increase in sound.

In TMPG, you can't put a normalize setting over 100%. I put normalize at 75% and then it analyzed the audio. It then adjusted the volume for me and increased it to 198.8%.

If I put normalize at 100%, the adjusted volume would be 265.1% and that is way too loud.

Do a test clip at 100% and see the sound difference,there wont be any.

I haven't done the test clip yet, but I was listening to the audio in the "Audio Effect", and it was considerably louder.

[johns0]

I just checked and found that you have to have audio edit checked to get the audio analyzed when normalizing,as i never use tmpgenc to encode the audio the best thing to do is then adjust to what level you like best when listening to the dvd when playing on your dvd player.The way i normalize audio is i run it thru besweet with the normalize to 100% checked on pregain,works much better than tmpgenc's audio engine.

[iantri]

There is a lot of misinformation in this thread: to clarify; normalization brings the volume level up to the point where the loudest sound is (when you normalize to 100%) exactly 0db -- the highest level of audio. Quieter sounds are measured in negative numbers.

Clipping is when audio is amplified to the point where the loudest sounds go past 0db -- this can not be recorded digitally so the audio is "clipped" at 0db and sounds distorted.

When you select Normalize to 100%, it then analyses the audio, determines the loudest part and determines how much it needs to boost the audio to make it 0db. In your case, it determined that it can safely boost the audio and sets the Volume change function to that amount; in your case, 198%.

If it needs to be boosted that much then it is probably because when you ripped the DVD and converted the AC3 audio, dynamic range compression was applied (DVDs have a far larger dynamic range -- the difference between soft and loud sounds -- than regular TV broadcasts) without a volume increase/normalization.

Johns0; you are confusing normalization with volume change; Volume change simply increases/decreases the volume without caring if clipping occurs.

Nocarebear; if it seems too loud when normalized it is probably because DVD audio the increased dynamic range causes most audio to be far lower in volume than TV audio -- when you normalize it to 100% you will find it to be far louder sounding than most DVD audio, but probably not far off from most TV audio. You can normalize it to something less if it bothers you. The whole point of normalization is, that, when normalized to 100% you are getting the loudest audio possible without loosing any sound.

[johns0]

iantriyou are misinformed,i didnt say normalization was only to change the volume,i know it is used to change the overall db to a certain level which is usually 0.your info isnt accurate in itself.If you had read my further post you would have seen that i dont use tmpgenc to encode audio but use besweet to "normalize" the audio.

[iantri]

I have read your posts.

You advise to listen to the audio and set the volume to a level "which you like best".

If not careful, this could result in clipping.

[nocarebear]

I did do a test clip and for that particular movie, the normalization at 75% did increase the overall volume during playback.

I now have an idea what normalization is. From now on, I'll let TMPG analyze the audio rather change volume directly and adjust accordingly.