Gaming Discussion of music file formats, bit rates, and file sizes!

[Roxie Faye]

[color=#9933cc]Uh, just what the title says. I basically don't know anything about music file formats other than mp3 (I'm not counting midi), and I was wondering if anyone had more information about a few things.

What types of files are most common, and do they serve certain purposes or anything?

Onto the next question, I just bought my first song off of itunes (Welcome to the 21st century, Roxie?). I bought it on my mother's mac and transferred it to my PC (damn, it took a long time to find the file on that mac!). And apparently it comes in an .m4a format, which my favorite music player - Quintessential player - doesn't play. I can either get a new player, or a new file format. I'm actually tempted to get a new player, but before I do, I wanted to know, is there any way to convert the .m4a to another format (like .mp3 or whatever) without losing [b]any[/b] of the quality? I don't want my 6.8MB .m4a file to get squished to 3.4MB .mp3 and sound like anything less than it is now.

Which leads me to my next question. What is the difference in quality? In your opinion, does the average person notice, or will they only notice with state-of-the-art speakers/headphones/whatever? What is considered the "standard" bit rate and what could be considered "CD quality"?
I understand that the downside to quality is space issues, but I'm not worried about that. I'm more concerned with getting a file (that plays) that sounds like a CD.

And uh, thanks in advance for answering my very, very silly questions. ^^[/color]

[Korey]

[FONT="Franklin Gothic Medium"]In all of iTunes's infinite wisdom, they created a file type that does not work for most media players outside of iPods. Talk about wanting to create brand loyalty :rolleyes: . I've tried some programs and they really don't help if you have to convert the files to MP3's, since they lose a generation going down a level.

As far as Audio files, the most common files used today are MP3's and MP4's (protected or not-protected). Windows has Windows Media Audio (.wma) format for their files and that is really comparable to an MP3 in my opinion. There's also .midi files, the kind of files you get on those old ringtones before they got "real"tones. You also used to hear those kinds of files used in older video games. Basically, .midi files are just sounds programmed to bleep and boop at certain times. It's not like actually playing an instrument and converting it into bleeps and boops.

But as far as quality goes, MP4's are the best quality of audio file that I've found. MP3's are nice, but sometimes when I download them, they end up pretty crappy. Not so with MP4's. So any song that you have in MP3 format can be converted to AAC (m4p) format and you'll actually hear the difference in quality.

Hope that answers your questions. [/FONT]

[John]

AAC is Apple's proprietary format. iTunes should have an option for you to change what format it rips your music into somewhere in the settings. I think you can set it to rip mp3s up to 192kbps, and that should be high-resolution enough for you, unless you've got a decent pair of headphones/speakers and have an ear for audio quality. When you set that, go back into your library and right-click on your song. There should be an option that says something like "Convert file to mp3". I'm not certain that this works with songs downloaded from iTunes, but it should.

Unless you plan on venturing into the expensive world of high-quality audio, I personally don't think there's any reason to use any file but mp3. It's far and away the most popular and well-supported, and the quality and compression are more than good enough for your average listener.

[quote name='Korey'][FONT=Franklin Gothic Medium]But as far as quality goes, MP4's are the best quality of audio file that I've found. MP3's are nice, but sometimes when I download them, they end up pretty crappy. Not so with MP4's. So any song that you have in MP3 format can be converted to AAC (m4p) format and you'll actually hear the difference in quality.[/FONT][/quote] I don't think so, Tim. mp3s can come at any quality up to 320kbps, I think, and that's beyond the capacity for most human ears to tell a difference. And converting a file from one format to another [B]absolutely cannot[/B] increase fidelity; it can only keep it the same or decrease it. It's just like converting a bitmap image into a high-quality PNG and expecting it to look better because of it.

[Desbreko]

[quote name='John']AAC is Apple's proprietary format.[/quote][color=#4B0082]iTunes uses AAC but the format itself isn't proprietary. Anyone can go download an AAC encoder and use it, or even code one themself. Personally, I use Nero's since, from the bit of research I've done, it's supposedly the best free AAC encoder available.[/color]

[quote name='John']And converting a file from one format to another [B]absolutely cannot[/B] increase fidelity; it can only keep it the same or decrease it.[/QUOTE][color=#4B0082]This is true. Converting from MP3 to AAC will only decrease the quality since both are lossy compression formats. Unless you have a good reason (such as a player not supporting a format), you should never re-encode a lossy format file.

[hr]100[/hr]
Anyway, browsing around Wikipedia can turn up a lot of useful information on this subject. Here's a good article to start with: [url=http://en.wikipedia.org/wiki/Audio_file_format][u]Audio file format[/u][/url]. It's also important to know the difference between [url=http://en.wikipedia.org/wiki/Lossless_data_compression#Audio][u]lossless compression[/u][/url] and [url=http://en.wikipedia.org/wiki/Lossy_data_compression#Audio][u]lossy compression[/u][/url] and those two articles will give you a list of formats in each type. From there you can read about specific formats in their own articles as well.

Another inportant thing to know is that MP4 is not an audio or video format, it's simply a container format for storing data streams. You can find see the various alternate file extensions used for MP4 files (such as .m4a which is common for MP4 files that only contain audio) in the [url=http://en.wikipedia.org/wiki/MPEG-4_Part_14][u]MPEG-4 Part 14[/u][/url] article. Some extensions signify things like whether the file is protected with DRM, but if a player doesn't support a specific one you can freely change it to another. Most MP4 files use the AAC audio format but they're also capable of storing MP3 and other formats.

To answer the questions simply...

? The most common lossy audio formats are MP3, AAC, WMA, and Vorbis and the most common lossless format is FLAC. MP3 has been around forever so nearly everything can play it. AAC is MP3's successor and technically superior but isn't as widely supported yet. WMA tends to be better than MP3 but about equal with AAC and is fairly widely supported. Vorbis, which usually comes in a .ogg container, is an open source audio format that tends to match or exceed AAC's quality but is even less widely supported ? pretty much nothing but computer software players support it. FLAC is open source and currently the most efficient lossless audio format but, again, good luck playing it on anything but a computer.

? You can convert from AAC (.m4a is the container format, not the audio format) to MP3 but not without loss of quality. This is true when converting from any lossy format to another lossy format. I'd recommend getting a new player if it doesn't even support AAC; there's a number of good ones out there. I use Winamp, myself.

? Unless you have a really good sound system and really good ears, you probably won't be able to tell the difference between MP3 and AAC at bitrates above 256 kbps. Likewise, you probably won't be able to tell the difference between a file encoded at 256 kbps and another encoded at 320 kbps or above.

? There isn't really a standard bitrate, it just depends on what sort of space vs. quality trade-off you want to make. True CD quality would be lossless FLAC but that's overkill for most things. To get files that are pretty much indistinguishable from the source, I'd recommend around 256 kbps. Using variable bitrate is also good, it can save a lot of space with no noticeable loss of quality.[/color]

[John]

Also, you might beware of upscaled mp3s. There are people who think converting a low-quality mp3 into a high-quality one will make it sound better, so you'll sometimes end up finding high-bitrate files that sound awful, and that'll be the reason.

[Roxie Faye]

[quote name='Korey'][FONT="Franklin Gothic Medium"]In all of iTunes's infinite wisdom, they created a file type that does not work for most media players outside of iPods. Talk about wanting to create brand loyalty :rolleyes: . I've tried some programs and they really don't help if you have to convert the files to MP3's, since they lose a generation going down a level.[/FONT][/QUOTE]
[color=#9933cc]That must be why I've never heard of an .m4a file type until yesterday - I've never owned an ipod, and I've never used itunes. The brand loyalty is also both ingenius (on the part of apple) and completely frustrating at the same time (for everyone else). Thanks for the info. ^^[/color]

[quote name='John']Unless you plan on venturing into the expensive world of high-quality audio, I personally don't think there's any reason to use any file but mp3. It's far and away the most popular and well-supported, and the quality and compression are more than good enough for your average listener.[/QUOTE]
[color=#9933cc]This is probably the best answer ever. Keeping everything in mp3 just makes life easier. Also, thank you for the advice on using itunes, should I need to convert a file. Sankyuuu.

Des: You are just a font of knowledge, you know that? ;) Really, though, I appreciate all of the explanations and wikipedia links. I looked over them and everything makes a lot more sense, now. I would use winamp, but the extensive library function on it turns on the OCD in me, and I decided a long time ago, for the protection of my sanity, to just give up on organizing my music six ways sideways from Sunday by forgoing a library altogether. However, the player that I do use (Quintessential Player - which supports mp3, wma, and vorbis), has a plug-in for AAC, which I just downloaded, and my shiny new .m4a song is playing quite nicely, so I'm happy about that. Thanks again![/color]

[Desbreko]

[color=#4B0082]Er, just to clear this up, Apple didn't create the MP4 container format (which has been around for years now), though it was based on their QuickTime .mov format. They just started using the .m4a extension to differentiate MP4 files that are audio only. If a player supports AAC but doesn't recognize the .m4a extension you can just change it to .mp4 and it should work.[/color]

[quote name='Roxie Faye'][color=#9933cc]Keeping everything in mp3 just makes life easier.[/color][/QUOTE][color=#4B0082]This is the kind of thinking that prevents newer and superior formats from gaining support. >_>; If no one uses them, support will be even slower to expand. I'm all for AAC completely replacing MP3.[/color]

[quote name='Roxie Faye'][color=#9933cc]I would use winamp, but the extensive library function on it turns on the OCD in me, and I decided a long time ago, for the protection of my sanity, to just give up on organizing my music six ways sideways from Sunday by forgoing a library altogether.[/color][/QUOTE][color=#4B0082]Heh, I never even touch Winamp's library or playlist functions. I just sort my files into directories by artist and album.

By the way, I think you can choose not to install the library functionality.[/color]