Helix MP3 Encoder instead of LAME (Recommended by me ;)
Posted: Sun Nov 20, 2011 8:15 pmHi!
This weekend I successfully implemented the use of the Helix MP3 encoder instead of the LAME encoder. I decided to use Helix, because it beat LAME in 128kbit listening tests and is ridiculous fast. CPU usage dropped by 50% on my server, thus preserving power and encoding time.
You can download the Helix MP3 encoder here:
http://www.rarewares.org/files/mp3/helix_mp3enc_CVS.zip
I've used the following encoding steps:
Step 1: ffmpeg -i %s -v 0 -f wav -
Step 2: hmp3 -X2 -U2 -V80 -HF2 - -
Alternative step 2: hmp3 -X2 -U2 -V80 -HF2 -SBT450 -TX0 - -
My target bitrate is about 160kbit here (VBR) and I've added the HF2 tag to enable frequencies above 16khz. I think this setting is transparent (most of the time). CBR encoding is possible, by not using the -V80 parameter, but using the B parameter, but beware: the bitrate is channel based, so 64kbit in Subsonic means a 128kbit total bitrate. When using a bitrate lower than V80 or 160kbit CBR you'll have to remove the HF2 tag, because otherwise it will negatively impact the sound quality.
Let me know what you think of it!
This weekend I successfully implemented the use of the Helix MP3 encoder instead of the LAME encoder. I decided to use Helix, because it beat LAME in 128kbit listening tests and is ridiculous fast. CPU usage dropped by 50% on my server, thus preserving power and encoding time.
You can download the Helix MP3 encoder here:
http://www.rarewares.org/files/mp3/helix_mp3enc_CVS.zip
I've used the following encoding steps:
Step 1: ffmpeg -i %s -v 0 -f wav -
Step 2: hmp3 -X2 -U2 -V80 -HF2 - -
Alternative step 2: hmp3 -X2 -U2 -V80 -HF2 -SBT450 -TX0 - -
My target bitrate is about 160kbit here (VBR) and I've added the HF2 tag to enable frequencies above 16khz. I think this setting is transparent (most of the time). CBR encoding is possible, by not using the -V80 parameter, but using the B parameter, but beware: the bitrate is channel based, so 64kbit in Subsonic means a 128kbit total bitrate. When using a bitrate lower than V80 or 160kbit CBR you'll have to remove the HF2 tag, because otherwise it will negatively impact the sound quality.
Let me know what you think of it!