lame3100i, a functional extension Options

[halb27]

You can download it from here.

What’s the functional extension?

It's an extension to Lame 3.100 alpha2.
It offers additional VBR quality settings -V5+ to -V0+ which cover the average bitrate range from 148 to 317 kbps (for a variety of pop music).

-V5+       148 kbps
-V4.5+    162 kbps
-V4+       176 kbps
-V3.5+    192 kbps
-V3+       208 kbps
-V2+       224 kbps
-V1.5+    240 kbps
-V1+       256 kbps
-V0.5+    291 kbps
-V0+       317 kbps

An alternative way to use the functional extension is --brV+ x, where x is the average bitrate (for a variety of pop music) you want to use, with x between 148 and 317. You can use for instance --brV+ 224 instead of -V2+.

What is it good for?

Lame’s moderate VBR quality settings like -V5 or -V4 usually yield a very good quality. That’s why many users are happy with these settings. Sometimes however tracks contain spots which are not encoded well. Many users want a better quality also for these rather rare events. From current experience Lame3.100 alpha2 quality of tonal problems seems to scale well with -Vn level, but temporal resolution can still be an issue.

-Vn+ uses -Vn as the encoding basis, but adds a certain amount of brute-force safety by forcing audio data bitrate to a target bitrate which depends on -Vn+ level. Moreover care is taken to always provide maximum possible audio data space for the encoding of short blocks which are used when the encoder thinks it is appropriate for a good temporal resolution. Also Lame's default lowpass is lowered a bit in order to make best use of the encoded bits (use --lowpass if you don't like this).

Emphasis is on issues with temporal resolution, but the higher quality levels starting with -V4+ can also have a positve effect for tonal problems.

In a sense -Vn+ combines the quality advantages of both VBR and CBR.

Recommendations

Users who care much about filesize and are content with the functional extension improving short block (pre-echo) behavior, can use -V5+ to -V4+.

Users who don’t like rather obvious issues in their music even when they’re rare but who also care about filesize are best to choose from -V3.5+ to -V1.5+ according to their needs.
For a significant potential for improving tonal issues -V3+ or better is recommended.

Users who don’t care much about filesize but much more about universal top quality are best served by using -V1+ or V0+, or anything in between. -V0.5+ is a good choice which is extremely close to maximum quality possible with lame3100i.

Installation

lame3100i.exe was compiled with Visual C++ 2010. For this reason it is necessary to install the Microsoft Visual C++ 2010 Redistributable Package vcredist_x86.exe. You can download it from http://www.microsoft.com/en-us/download/details.aspx?id=8328.

lame3100i.exe uses the fast and lossless mp3packer tool internally to squeeze the otherwise unused bits out of the mp3 file. You can download mp3packer from http://www.hydrogenaudio.org/forums/index....st&p=282289. Put mp3packer.exe into the same folder where lame3100i.exe is located. Many thanks to Omion for this great tool.
In case there is no mp3packer.exe in lame3100i.exe’s folder lame3100i.exe will work, but the mp3 files will be somewhat larger than necessary.

This post has been edited by halb27: Feb 15 2013, 10:17