Avidemux Forum

Avidemux => Unix-Like (Linux/Bsd/...) => Topic started by: Fleabag on March 13, 2012, 10:58:38 PM

Title: Confusion over codecs.
Post by: Fleabag on March 13, 2012, 10:58:38 PM
What is the difference between MP2(lav), and MP2(twolame)?
Title: Re: Confusion over codecs.
Post by: Jan Gruuthuse on March 14, 2012, 08:27:24 AM
QuoteTwoLAME is an optimized MPEG Audio Layer 2 (MP2) encoder. It is based on tooLAME by Mike Cheng, which in turn is based upon the ISO dist10 code and portions of LAME.

TwoLAME does NOT support MPEG Audio Layer 3 (MP3) encoding due to patent issues surrounding MP3.

However, as most MPEG Audio players are able to play layer 2 (MP2) files, TwoLAME makes a very good drop-in replacement for LAME and other layer 3 encoders.
source: Debian Package: libtwolame-dev (http://packages.debian.org/squeeze/libtwolame-dev)

Quote7.8.4. Encoding Audio

VCD and SVCD support MPEG-1 layer II audio, using one of toolame, twolame, or libavcodec's MP2 encoder. The libavcodec MP2 is far from being as good as the other two libraries, however it should always be available to use. VCD only supports constant bitrate audio (CBR) whereas SVCD supports variable bitrate (VBR), too. Be careful when using VBR because some bad standalone players might not support it too well.

For DVD audio, libavcodec's AC-3 codec is used.
source: MPlayer: Using MEncoder to create VCD/SVCD/DVD-compliant files (http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-vcd-dvd.html)
Title: Re: Confusion over codecs.
Post by: Fleabag on March 14, 2012, 02:57:43 PM
OK, that tells me what MP2(Twolame) is, but does NOTHING to explain the difference between that and MP2(lav).
Title: Re: Confusion over codecs.
Post by: styrol on March 14, 2012, 03:04:59 PM
QuoteThe libavcodec MP2 is far from being as good as the other two libraries
Well, it does explain it indeed, if you are familiar with video encoding: quality respectively quality-size ratio is not as good.

QuoteOK, that tells me what MP2(Twolame) is, but does NOTHING to explain the difference between that and MP2(lav).
Yes, we all know you are able to format a word in upper case, bold and underlined all together. Using only one formating would be more appropriate and convenient.
Title: Re: Confusion over codecs.
Post by: Jan Gruuthuse on March 14, 2012, 04:02:49 PM
@Fleabag
QuoteTwoLAME does NOT support MPEG Audio Layer 3 (MP3) encoding due to patent issues surrounding MP3.
QuoteFor DVD audio, LibAVcodec's AC-3 codec is used.
Title: Re: Confusion over codecs.
Post by: Fleabag on March 14, 2012, 06:07:38 PM
Thank you.