Ogg vbr = Lame Mp3 vbr?

[jkwarras]

HI,

See if anyone can clarify something i have in mind :)

I always use Lame MP3 to compress AC3 movie sound. I use Beesweet and follwing settings:

- joint stereo
- VBR NEW (two times faster, same quality as OLD in lame 3.93)
- Max bitrate=320 / Min bitrate=32
- Quality=1 5nearly perfect)

The encoded files usually end with a bitrate around 112-150, depends on the movie, but the quality is just perfect, the codec just take what it needs. NO crackling or strange mp3 artifacts.

Yesterday i just tried for the first time OGG format. I didn't want to used the quality settings because is a ABR encoding, as in lame ABR. I wanted to test the same kind of encoded beetween ranges of 32-320 kbps and let the codec decide the bitrate it needs. I've used beesweet for that and surprise!! The file ends with a bitrate much inferior than the same encoded file with lame mp3 VBR.

A AC3 6 channels 1h50min:
- LAME MP3 VBR 32-320 kbps= around 112 kbps
- OGG VBR 32-320 kbps= around 96 kbps

My question, as the file really sounds the same to me, is this encodes method with OGG equal to the MP3 i'm using until now, becasue if it is, i think i'm going to switch immediatly to OGG :)

The OGG format really needs less bitrate to sound equally to MP3? And finally, does 96 kbps in OGG format equals to 96 kbps in MP3?

Lot of questions, if anyone can answer me, thanks :)

[tiki4]

Hi jkwarras,

first, if you use LAME then for God's sake use the --alt-preset's. No fumbling around with LAME switches and it gives you highest possible quality from LAME. Version 3.93 has broken --alt-preset modes so get LAME 3.93.1 from Mitiok's site or just use the BeSweet included lame_enc.dll 3.92, then you just need '--alt-preset standard', which gives you around 160 kBit/s for an ordinary movie. If you think that's too slow (old VBR) then just use '--alt-preset fast standard'. You get less bitrate with one of the ABR switches like '--alt-preset 128' for 128 kBit/s ABR.

Ogg Vorbis: The codec is tuned for use with the quality switches, so just use '-q 0...1', whatever fits your needs. I often use '-q 0.4' which sounds pretty decent for my ears and gives around 110 kBit/s. As Ogg Vorbis is tuned in the low bitrates, a 96 kBit/s Vorbis file is of equal if not better quality than 128 kBit/s MP3 IMHO. You even can check the 64 kBit end, which was found to sound very good compared to other 'lowbitrate' codecs (like WMA, MP3PRO, AAC...). So if you ask me: Use Ogg Vorbis and just do a short test which quality switch sounds best to you.

Hope that helped a little bit.

tiki4

[jkwarras]

Ok, I got all wrong :) First of all there's no way to do a TRUE vbr beetween a expecifed range of bitrate (min 32 max 320 kbps) with OGG in Beesweet or OGGmachine. It always use an average bitrate of 160 and goes up and down within the max and min bitrate expecified, but it used an average bitrate, so no real VBR for me, as you force ogg to stay around 160 even if the sound don't need more bitrate.

The only way to do this is with oggenc.exe that can be found in the vorbis website. But is not suitable to ancode ac3 to ogg because it only allows a WAV->OGG compresion. But i've done some test and same settings for lame and ogg (min 32 max 320 VBR - NO AVERAGE bitrate), OGG always use more bitrate than LAME; For ex. for music tracks, if LAME use 150 kbps, OGG use 220 kbps; Maybe the sound is just better, but for movies i don't see the point to switch to OGG if LAME give me better results when doing a real vbr encode; FOr lower bitrates it's true, OGG sounds better doing ABR encodes at 64-96 kbps (q0.?)

[jkwarras]

Originally posted by tiki4
Hi jkwarras,

first, if you use LAME then for God's sake use the --alt-preset's.

I was using presets before, but right now i understand how it works, so i prefere to encode like this, because it really give me the best quality, as the ocdec just take what it needs, ni more no less; I was using the OLD vbr until lame 3.93 came out. I've done some test and it's true, NEW vbr is twice faster and it gives you similar quality, just by hearing, to me anyway (as always is just a matter of taste).


No fumbling around with LAME switches and it gives you highest possible quality from LAME.

I love to flumb around with settings and things, as long as i understand more or less what i'm doing; if not, i don't touch :) The presets are very good, but you can get more of it just playing a little more.

Version 3.93 has broken --alt-preset modes so get LAME 3.93.1 from Mitiok's site

I didn't know that, thanks a lot.

Hope that helped a little bit.

It always help to discuss; Cheers

[tiki4]

Sorry, mate,

you got me wrong, I think. I was talking solely about three of the numerous presets of LAME.

The VBR presets are:

--alt-preset standard (3.90 to 3.92), now --preset standard (3.93.x)

--alt-preset extreme (3.90 to 3.92), now --preset extreme (3.93.x)

--alt-preset insane (3.90 to 3.92), now --preset insane (3.93.x).

The last one is identical to --alt-preset cbr 320, using maximum MP3 bitrate.

There are also the ABR presets, which you can access like:

--alt-preset 128/160 and so on (in 3.93 versions again --preset bitrate).

The three true VBR switches have been highly tuned over at hydrogenaudio.org by Dibrom and give you the absolute best quality from LAME. All the older presets like radio, fm and so on are outdated, the same is true for --r3mix.

The VBR modes can be switched from the old to the new VBR by adding a fast in the command line (e.g. --alt-preset fast standard). You don't really need to bother with other switches in LAME as those alternative presets give you really high quality audio.

I don't know why the LAME developers decided to merge them with the older presets in LAME 3.93 as this seems to cause confusion. Also those presets were broken in 3.93 and give you inferior quality, so under all circumstances get 3.93.1 or stick with 3.92 which is pretty stable. You can find the whole discussion in the MP3 section of hydrogenaudio.org.

Regarding Ogg Vorbis: You can encode to Vorbis from BeSweet. You just have to install the Ogg DirectShow filters of Tobias Waldvogel. Then you also need not bother about bitrate, just use the quality switch that fulfills your needs. Don't bother with the rest, Vorbis was made to be used like that, everything else is not necessary. Fot 96 kBit/s you may use -q 0.2 in BeSweet (in oggenc.exe -q 2), you won't hit the point exactly, but Vorbis is VBR so it takes what it needs to get a specified quality.

Regards,

tiki4

[tangent]

1. --vbr-old is definitely superior to --vbr-new/--vbr-mtrh. To many people, the difference may not be audible and not worth the hit in speed, but to the experienced listeners, the differences can be heard. Most people encoding for archival purposes would accept lower speed for better quality, so --vbr-old has been defaulted in the --alt-presets.

2. There should be absolutely no reason to use your own --vbr-* command lines. For VBR, you should only be using the --alt-presets. If you think you "understand how it works", then obviously you haven't understood enough because the VBR --alt-presets are not based off command line switches but internal code level tweaks. Below the bitrate of --alt-preset standard, it has been shown that using ABR provides more stable quality than VBR, so you should never ever be using your own vbr command lines.

3. You are using Ogg Vorbis VBR the wrong way. Use the quality settings. In general:
q - approximate kbps
0 - 64
1 - 80
2 - 96
3 - 112
4 - 128
5 - 160
6 - 192
7 - 224
8 - 256

Besweet uses q divided by 10

Using managed bit rates (e.g. by specifing min/max/average) can lower the quality of the Ogg Vorbis encoding.

4. http://www.hydrogenaudio.org