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Audio Format Transcoding for Compatibility?
brandorf asks: "With the multitude of compressed audio formats that are available today, (MP3, Ogg, AAC, and FLAC to name very few) our music libraries start to spread across quite a few different formats. While this isn't a problem for desktop/media PC use, as programs like Winamp or iTunes have plugins available for almost every format. However, when it's time to start using a portable unit, it's unavoidable that some files will get transcoded. Have there been any studies or experiments as to how similar the codecs really are? Will transcoding from Format A to B sound worse than going from A to C? What's your experience with this?"
http://www.hydrogenaudio.org/forums/index.php?show topic=32440
The site insists on proper ABX tests too, not some thirteen olds insisting they can tell the difference between FLAC and Monkey's Audio codecs.
Use a lossless format for archival purposes (any format really since you won't use it on your portable), then use MP3 for everything else. MP3 is the only thing that pretty much every portable can play. OGG and Windows Media are a close second but I would never consider Windows Media format.
I've noticed significant reduction in lows and an unsettling amount of distortion when I go from vinyl to wax cylinder.
"There are no facts, only interpretations." --Friedrich Nietzsche.
If you have a lossless source, the quality of the derived audio should be as good as an original rip of the CD itself. That's the whole point of lossless encoding. If you're going from lossy->lossy, then any transcoding will introduce garbage, but how much garbage depends on how good the original source is. .anacron
"Hasn't this been asked a thousand times already"
No, RTFA. I'll give you a little clue: read the bit about A to B and A to C.
"Derp de derp."
ive burned about 40-60 cd's (either mine or my family's) as 160 bit rate. late on i need my hard drive space so i compresed them to 128. I can't hear a difference. This dosent answer the question but it would be like going from .mp3 to .mp3. BTW i have a bad ear from getting opened hands to the ear(sports not abuse) and from genitics.
Well, in the real world, I'd say the best source format is the one you got, and the best target format is the one you need. Duh.
:P
But still, on a theoretical level, the question IS interesting. The hydrogenaudio link above only compares very few codecs, and I'd especially like to hear more about codecs I am forced to use (like WMA or RA), since all OGG etc. files I've got are encoded by myself, and I would have had the chance to encode to the desired target format right away.
On a somewhat related note, I've been wondering if there are some codecs which don't have to be expanded to uncompressed and then recoded, but could use a part of the original compression and only rewrite a part of the data? That would, obviously, cut down on quality loss.
Also: Since everybody else has mentioned it, I don't want to be the only person here not to reply that LOSSLESS OWNS THE SKY FLAC CAN SOOTHE YOUR EARS UNCOMPRESSED WAV STYLE
Seriously. Encode your music in a lossless format, then transcode it to whatever lossy format you use on the go. Sure, it's much bigger, but it will be bit-for-bit accurate! Even if you can't tell the difference on your $50 computer speakers and bundled iPod headphones, you can feel good because you know it's better.
Also, it will get you laid.
Love, your hard drive manufacturer.
Pick your format and make a high quality rip (256kbps mp3 for example) then if you want a wma or ogg or whatever burn a disc and re-encode it for that file format. you arent going to get any problems with converting from one file format to another and quality should be no worse than the original file.
Supplies!
encode from mp3 to flac ... ;)
Electronic Music Made Using Linux http://soundcloud.com/polyp
If you use any reasonable lossy codec at a high enough quality setting, it's essentially the same as a lossless codec, and you still save space compared to the lossless (bit accurate) codecs.
I encode .flacs and CDs straight to .oggs and most everything else I've ended in with my collection is in MP3. For the stuff that really matters, most is in the 256-320/k range CBR. The oggs I encode are all 350 ABR, for what its worth sounds really, really close to a CD and certainly better than MiniDisc. I'd love to just store nothing but FLAC, but I would need to start looking at quadrupling my file server's capacity, which would put me over a terabyte. Also since I run slimserver on my file server and stream everything out to my client PCs in MP3 (Can someone explain how to stream in wav and make it work with winamp?!) I usually take the odd WMAs and such and convert them to the highest possible MP3s, since they will be transcoded down the line eventually anyways. Like the other day I did it to a david gray album. A david gray album isn't really pushing the sonic boundaries like an orchestra so it gets to a point where compression isn't nearly as noticable. It doesn't usually sound so bad, but certain bitrates sound a whole lot worse than others. A lot of hip hop sounds ok in 192k and even some old rock sounds ok, especially when the original recording was lo-fi to begin with. Electronica can sound good at a variety of bitrates, the biggest thing you lose really is some of the high end spectrum and it likes to chop the bass to pieces, especially at low bitrates like 128.
Like here, I have this crappy busta rhymes album I was listening to, and some idiot decided 162k was enough for them. It sounds terrible. To the morons out there that share this crap, please at least use a decent bitrate. Just because you get a smaller file size doesn't mean that it'll sound the same or even comparable. Nothing sucks more than grabbing a random torrent file and finding that the contents are all in crappy bitrates.
I guess for most people its a matter of preferences. If you are an audiophile you probably wouldn't even be asking the questions, so in short, high bitrate MP3s are ok, oggs sound great, so get a player that plays both and encode everything new to ogg.
Now, will someone please tell me how to stream wav or flac with slimserver to winamp if it is possible?
zosxavius photography
I back up my cd's to ogg at a high bitrate, usually VBR averaging about 256kbit. I do all my transcoding from those 256kbit masters. On occasion I need to fit them on a small mp3 player or pack a bunch onto an mp3 cd, in which case 128 is desirable. I can barely hear distortion at 128, and only with a few songs.
Maybe you should be more selective about the stuff you steal...
or did you encose in all those formats because you're really that dumb?
Which one is it?
Hard drive space is plentiful. Just rip everything to a lossless format, such as FLAC, or even .wav or .aiff if you can't be bothered with the hassle, then make a convenient shell script to convert everything into another format as and when required. That way, you get the best sounding MP3s or Ogg Vorbis files with none of the bad side effects of transcoding, and as soon as any given codec is improved or replaced by a better one, you won't have to worry about not taking advantage of the shiny new algorithms.
Maybe you need a structure for your audio files.
I assume that most of your recordings are music (vs. spoken words or whale songs.). Where are you getting the files from? If you are encoding them yourself, then pick FLAC if you've got the space. Lossless will guarantee that you don't get artifacts, at the expense of storage space. If are ripping from CD, you'll want to have as high a quality as possible - unless you have a small collection, you won't want to go through the ripping process several times. If you can't rip into FLAC, pick a very high OGG or MP3. OGG should give you better quality for the same bitrate, while MP3 is a standard. If you go with a very high bit rate MP3, eventually you won't need to down-sample it, because storage is getting cheaper.
I would also recommend against keeping multiple versions of the same file, cause it would suck to lose the high quality archival files in a cut-and-pastectomy error.
The only other source of other formats is you are buying them or downloading them. Well, you'll have to take what you can get, but you would probably be better off buying the CD, since the hard media will survive a disk crash, you get control over the digital encoding, and you don't have to deal with any funky copy protection. Of course, the tradeoff is $$$.
No, I don't trust in god. He'll have to pay up front, like everybody else.
Requantizing audio of a given format to reduce its bitrate is likely to cause less of a problem than switching formats.
Simply put, each format has different criteria on what information is thrown away and what is not. Thus, for example, something that MP3 may keep but AAC throws away will not be present if you transcode from AAC to MP3, IN ADDITION to losing anything that AAC keeps but MP3 throws away. The same holds true in reverse.
retrorocket.o not found, launch anyway?
But what tools do you use?
I have a load of AAC from iTunes (ok, pymusique, thanks chaps) and I'm havinga hard time getting mencoder or something to convert them to mp3.
I know its a doddle and I'm looking in the wrong place, so it would be nice to see what command line tools (and spells of tools) folk are using to transcode?
Sam
blog.sam.liddicott.com
Is there a way to pop a (paid for) DVD, DVD-A, SACD, or DTS-CD into my computer and get MP3's out of it?
I challenge you to ABX any 2 or 3 recordings of your choice. Rip them with EAC, and encode them with Lame 3.90.3 --alt preset standard.
ABX against source, or wav, or flac - I don't care.
If you haven't done so you need to keep out of such conversations.
I only speak for myself, but I know that I consider it silly encoding anything above about 150kbps ABR Ogg Vorbis, because above that, I can't hear the difference. I've been used to listening to 128kbps CBR MP3s for so long that I can't tell the difference any more. Sure, they're crappy PC speakers, but why bother with anything better if I simply cannot tell the difference. A musical friend of mine tried to test this - he played me a song twice, at different bitrates - I couldn't hear any difference. Surely you're listening to the wrong sort of music if you get distracted by the bitrate.. I mean, if it's *really* low then there's obvious reason, even I can tell at the extreme low end of the bitrate spectrum. I'd rather have manageable filesize and reasonable quality. However, I demand more digital music players to be ogg vorbis compatible! What I wouldn't give for one of those sleek HP jukebox jobbies.. *drools*
Doing the shorter clips was the hardest part, though I know it applies to very few people, hopefully you'll find it useful.
Are there any formats that offer high compression without loss? At some point you'd definately end up trading storage-space for CPU+memory, but for the latter they're only used on an as-needed basis and as time goes on the CPU power to handle this will increase as well.
right, or a highpitched warlbling like a echo under water.. dont be envious theyre just deaf.