[Icecast] converting mp3's to aac+ or ogg

Chris MacDonald chris at thoughtsoft.net
Mon Jun 26 19:21:51 PDT 2006


For archiving from source media (CD usually) to flac? I typically use 
EAC either from Windows or Wine as it allows for the most configuration. 
Off the top of my head I think Sound Juicer will do it for *nix, though 
there are probably others that work just as well.

Chris

Dave wrote:
> Hi,
>    Thanks. As is usually the case circumstances kind of put this 
> project on a few days hold, but i was wondering what do you use for 
> flac conversion?
> Thanks.
> Dave.
>
> ----- Original Message ----- From: "Chris MacDonald" 
> <chris at thoughtsoft.net>
> To: "Dave" <dmehler26 at woh.rr.com>
> Cc: <icecast at xiph.org>
> Sent: Sunday, June 25, 2006 7:03 PM
> Subject: Re: [Icecast] converting mp3's to aac+ or ogg
>
>
>> Taking the 128 mp3 and re-encoding to flac won't fix any quality 
>> issues you may have as they will retain the same 'flaws'. In the end 
>> you'll end up with the same quality as you would have seen going from 
>> 128 mp3 to q3 ogg. One nice thing about ezstream is that you can 
>> specify decoders for multiple formats so if going and ripping all 
>> your media again is too daunting a task you could just use the mp3s 
>> you have, then slowly start ripping to flac as you have time and 
>> ezstream will take care of using the right decoder.
>>
>> I'm flattered you think I have customers and all manner of users ;) 
>> but I just use ezstream/icecast for myself, at least for now I just 
>> have my one stream. As an example configuration just take a look at 
>> the vorbis example that comes with ezstream. It's very close to what 
>> you want, and any changes you need to make are pretty 
>> straightforward. Take note though, the stream information in the 
>> configuration is informational only, to actually modify the encoding 
>> options of the stream itself.  Look under the 'reencoding' section of 
>> the config and modify the command ezstream will use as the encoder. 
>> Any options for oggenc you can find out by checking out the man 
>> pages, but you probably just want to play with the with the quality, 
>> in which case you'd change '-q 0' to whichever you'd like.
>>
>> To my knowledge it isn't possible to get icecast or ezstream to 
>> change the bitrate of the stream dynamically to meet a client's 
>> bandwidth restrictions so what you'd want to do is have two streams, 
>> one low quality and one high quality. For this you'd be running two 
>> instances of ezstream, each with their own encoder settings to change 
>> the quality to suit your needs.
>>
>> Chris
>>
>> Dave wrote:
>>> Hi Chris,
>>>    Thanks. What i've got are 128kbps mp3's. I encoded them using 
>>> abcde as it did everything with one command and worked over an 
>>> entire CD. It used lame as it's backend and encoded at 128k. 
>>> Question, what if i went from mp3 to flac, which would enable me to 
>>> have my original mp3's as they are, plus a mirrored area of flac 
>>> files, then use ezstream to send those flac files as ogg. If that 
>>> wouldn't blow to much up quality wise i'd rather do it that way than 
>>> reencode everything. For your streams do you have both dialup and 
>>> broadband users? If so, i'd like to see your reencode settings so i 
>>> will know what to punch in, so far getting the quality right has 
>>> been hit and miss. Are any of your customers windows users using 
>>> winamp?
>>> Thanks.
>>> Dave.
>>>
>>> ----- Original Message ----- From: "Chris MacDonald" 
>>> <chris at thoughtsoft.net>
>>> To: "Dave" <dmehler26 at woh.rr.com>
>>> Cc: <icecast at xiph.org>
>>> Sent: Sunday, June 25, 2006 6:09 PM
>>> Subject: Re: [Icecast] converting mp3's to aac+ or ogg
>>>
>>>
>>>> Yeah, ezstream is a source client just like ices0, but the manner 
>>>> in which they go about processing files or playlists may differ. I 
>>>> don't know too much about ices0 but in the configuration for 
>>>> ezstream you can either specify a single file to stream or you can 
>>>> point it to an m3u playlist and it will play though that, I'm not 
>>>> sure this is compatible with how you currently queue media.
>>>>
>>>> In terms of quality, I'm pretty picky which is why I wanted my 
>>>> source media in a lossless format. I chose flac but there are 
>>>> others, think wav + compression; tracks I archive are usually 
>>>> 50-80% of their raw size, of course this varies from track to 
>>>> track. In your case going from mp3 to ogg, your ability to notice a 
>>>> difference will depend on the bitrate of the source mp3 and the 
>>>> resultant ogg stream. Something like a 256kbps vbr mp3 to a q3 
>>>> (~110kbps vbr) ogg vorbis stream will still sound fine (I did this 
>>>> before deciding to do al my archiving in flac), but if you took a 
>>>> 128kbps mp3 and did the same you'd notice the change. Again, it 
>>>> varies from person to person and I'd imagine you'd just have to try 
>>>> it yourself to see what you'd like, it's less a science and more a 
>>>> preference.
>>>>
>>>> The box that does my re-encoding on is an AMD 1800 with 512MB RAM 
>>>> and also does icecast, apache, mysql, sendmail, pretty much the 
>>>> whole shebang and I haven't had a problem. Though, mind you I'm 
>>>> only re-encoding for one stream whereas you'd be doing multiple 
>>>> streams. The flac decoder seems content with ~2% of the processor 
>>>> and the ogg encoder seems to like ~40% and again, this is hardly a 
>>>> science and undoubtedly 'your mileage will vary'.
>>>>
>>>> Chris
>>>>
>>>> Dave wrote:
>>>>> Hi Chris,
>>>>>    Yes that helps a lot, thanks. I'm currently using ices0, which 
>>>>> worked fine when all i wanted to stream was mp3's. You've sold me 
>>>>> on ogg, and ezstream can it work as ices0 does? As i said i'd 
>>>>> really not like to do all this reencoding again, how much of a 
>>>>> quality loss will i be looking at if i go from mp3 to ogg? I'm not 
>>>>> familiar with the flac format at all. Does it have any kind of 
>>>>> compression, i'd rather not have something like all these wavs 
>>>>> around or similar if i could help it. As for the box how much of a 
>>>>> hit will it take? What kind of machine do you use for your encoding?
>>>>>    Thanks.
>>>>> Dave.
>>>>>
>>>>> ----- Original Message ----- From: "Chris MacDonald" 
>>>>> <chris at thoughtsoft.net>
>>>>> To: "Dave" <dmehler26 at woh.rr.com>
>>>>> Cc: <icecast at xiph.org>
>>>>> Sent: Sunday, June 25, 2006 4:46 PM
>>>>> Subject: Re: [Icecast] converting mp3's to aac+ or ogg
>>>>>
>>>>>
>>>>>> Hey Dave,
>>>>>>
>>>>>> Personally I use ezstream as a source client as it's designed to 
>>>>>> re-encode your stream (it's available at www.icecast.org). I've 
>>>>>> set up my radio to re-encode my archived flacs to ogg vorbis then 
>>>>>> out to icecast and it works quite well.
>>>>>>
>>>>>> As for quality, vorbis is apparently one of the nicer formats at 
>>>>>> low bitrates. I'm not sure about aac though, I'd imagine there 
>>>>>> isn't much in the way of support for it so you'd be much better 
>>>>>> off with ogg. Either way though, re-encoding from a lossy format 
>>>>>> (mp3) to another lossy format (ogg/aac) you'll notice some sound 
>>>>>> degradation from your source mp3, this is entirely why I archive 
>>>>>> in flac.
>>>>>>
>>>>>> I'm not sure what you want to do for dialup/broadband quality 
>>>>>> settings but I'd probably just run two mounts for each station, 
>>>>>> one low bitrate and one higher. One thing you have to keep in 
>>>>>> mind though is that all this re-encoding would happen on the fly 
>>>>>> so you need to make sure the machine you'd be doing it with was 
>>>>>> up to the task.
>>>>>>
>>>>>> Not sure if any of the above helps, but I'd imagine it presents 
>>>>>> some options at least.
>>>>>>
>>>>>> Chris
>>>>>>
>>>>>> Dave wrote:
>>>>>>> Hello,
>>>>>>>    I've got a FreeBSD 6 machine running icecast2 and 
>>>>>>> ices0streaming four different streams of mp3's. Now i have a 
>>>>>>> need to stream the same content as either aac+ or ogg vorbis 
>>>>>>> whichever would be easiest to set up and give the best quality. 
>>>>>>> I want these new streams to handle both broadband and dialup 
>>>>>>> users without sacrificing quality. My problem is i really really 
>>>>>>> do not want to have to manually go through my media again and 
>>>>>>> bring them in to aac+ or ogg, doing it once for mp3 was bad 
>>>>>>> enough. I used abcde to handle this, and as i said i'd like to 
>>>>>>> find an automated way of reworking these files. Any suggestions 
>>>>>>> welcome.
>>>>>>> Thanks.
>>>>>>> Dave.
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Icecast mailing list
>>>>>>> Icecast at xiph.org
>>>>>>> http://lists.xiph.org/mailman/listinfo/icecast 



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