I just wanted to say that I really like this codec for it's speed! I've taken to using this in foobar to transcode lossless to MP3 for my flash portable (iAudio G3), and on average it takes only 1:00 to 1:15 to transcode a single album, vs. 3:30 to 4:00 with LAME vbr-new (w/ dual-core processor).
I realize that quality may not be up to LAME per listening tests (and general public perception) but it's quite adequate enough for my temporary transcodes (non-golden ears, listening on cheaper headphones).
Has there been any further development on this encoder? I assume not; I'm using the version up at rarewares last updated December 2005.
I currently use -V75 (yields bitrates roughly equivalent to LAME -V4) -X2 -U2 in my command line. Would someone be able to explain in layman's terms what the -TX switches do (and if one is already default), and/or what tweaking the SBT accomplishes? For reference I've put the hmp3.exe -help below - I find it to be a bit cryptic.
file-file MPEG Layer III audio encode v5.1 2005.08.09
Copyright 1995-2005 RealNetworks, Inc.
Usage: mp3enc <input> <output> [options]
<input> and/or <output> can be "-", which means stdin/stdout.
Example:
mp3enc input.wav output.mp3
Options:
-Nnsbstereo -Sfilter_select -Aalgor_select
-C -X -O
-D -Qquick -Ffreq_limit -Ucpu_select -TXtest1
-SBTshort_block_threshold -EC
-h (detailed help)
B[bitrate]Per channel bitrate in kbits per second.
Encoder will choose if -1. (default)
M[mode] Select encoding mode: mode-0 stereo=0 mode-1 stereo=1 dual=2 mono=3.
V[vbr_scale]
Selects vbr encoding and vbr scale. Valid values are 0-150.
N[nsbstereo]
Applies to mode-1 stereo mode only. Number of subbands to
encode in independent stereo. Valid values are 4, 8, 12, and 16.
The encoder limits choices to valid values. The encoder
will make a default selection if nsbstereo = -1.
Valid values for Layer III are 3-32.
S[filter_select]
Selects input filtering: no filter = 0, DC blocking
filter = 1.
if filter = -1 the encoder will choose (default)
A[algor_select] 0 = track input, 1=MPEG-1, 2=MPEG-2, xxxxx=sample_rate
C c0 clear copyright bit, c1 set copyright bit
O o0=copy, o1=original
X MPEG compatable Xing header, -X2 with/TOC
U u0=generic, u2=Pentium III(SSE)
Q disable_taper, q0 = base, q1 = fast, q-1 = encoder chooses
D Don't display progress
F Limits encoded subbands to specified frequency, f24000
HF high frequency encoding. Allows coding above 16000Hz.
hf1=(mode-1 granules), hf2=(all granules), -B96 or -V80 need
TX tx6, test reserved 6 or 8 seems best (startup_adjustNT1B)
** v5.0 TEST 1 as of 8/15/00
** v5.0 TEST 2 8/18/00
** v5.0 TEST 3 default tx6 (prev = tx8)
** v5.0 TEST 4 mods to short fnc_sf, ms corr. hf enable > 80
** v5.0 TEST 5 fix odd npart, ix clear
** v5.0 TEST 6 add reformatted frames
** v5.0 TEST 7 drop V4 amod
** v5.1 2005.08.09 (see CVS log for details)
SBT[short_block_threshold]
short_block_threshold default = 700
EC Display Encoder Setting