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Audio Options in Vidcoder

Jun 22, 2013 at 10:04 PM
Edited Jun 22, 2013 at 10:14 PM
I quite familar with the terminology of dynamic range etc using Handbrake and well used to Belight's excellent options, I just wanted some info please on Vidcoder's features.

According to Handbrake 0 turns off Dynamic Compression but in Vidcoder 0 is valid. Valid from 0 to 4 according to option.

Q.So is this "0" "normal" DRC I presume like in Staxrip's audio options?

Also to quote Handbrake "Dynamic range compression only works when the source audio is AC3 and you are encoding to another format, like AAC. It has no affect on AC3 pass-through or on DTS or MPEG-2 audio."

Q.Is this true in Vidcoder, because this option also appears using codec mp3 (Lame) with mixdown Dolby Prologic II and does it work on an existing mp3 track?

I noticed this when my inputted Avi source had a mp3 track. I thought the DRC option would not appear if the source has a mp3 track rather than ac-3.

Also "Gain" is self explanatory, but I'm a little confused by the compression 0 to 9 option above it which is defaulted to 2. Is that an additional "helper" to DRC?
Thanks for an excellent piece of software.
Jun 22, 2013 at 10:52 PM
0 is no DRC: it doesn't do anything to the audio. About the DRC only working for AC3 sources, this is the first I've heard of it. HandBrake does not hide the DRC box when you have an input track like AAC.

Compression isn't really like DRC: it doesn't change the audio; it's just a number you give the encoder to tell it how hard to work to compress the audio. More compression means you get smaller file sizes but it takes longer to encode.
Jun 23, 2013 at 11:54 AM
Edited Jun 23, 2013 at 11:58 AM
According to their Handbrake guide it only works for AC-3 sources in terms of compatibility!

In anycase I'm not using Handbrake options, but using Vidcoder's instead.

Might I ask further that when you are using AC3 sources 5.1 surround and encoding to mp3(downmix Prologic II) what is the best number for inputting as a "Gain" and for using "0 to 4" for DRC as number, if they are both used together?

Thanks RandomEngy for your reply.
Jun 24, 2013 at 3:41 AM
I have not had occasion to use DRC yet as I have not encountered a source that needed it. I use Gain when I want to make things louder.

Looks like you're right about the DRC only working on AC3 sources. However I don't want to make it disappear; I think I will gray it out when it doesn't work and add a tooltip describing what it's compatible with.
Jun 24, 2013 at 3:49 PM
Edited Jun 24, 2013 at 4:04 PM
I always find aac though it is vastly superior to mp3 at lower bitrates never seems to normalize for me correctly using any method available.
I assume the "Gain" approach will still work on an aac/mp3 source tracks, if the DRC now doesn't?

AC-3 is problematic too. Reading into the "gain method" there is always a considerable drop encoding a 5.1 ac-3 track to mp3, and quite a lot of transcoders add between 6-10db to counteract it in a normalization/audio boost process as part of their program e.g Azid. Even encoders I've used normalizing at a default 89% or 95% etc always result in high clipping/over modulation. Belight etc produces clipping. The L and R channels of an encoded mp3 track from a 5.1 track can sometimes also have big channel differences due to source structure, I always use Mp3 to easily remove the clipping after an analysis or correct the channel difference (if it is over 1%) earlier on before final downmixing, as any final correction kills the surround phase .
Jun 24, 2013 at 8:33 PM
Yes I believe that Gain works on all sources.