asf convert to MP3 and the size is 10 times bigger!!!

[pachow]

Hi Spoon and all,

First of all, may I express my sincere thanks to Spoon since he is the first one that could provide a program to me to solve my problem!!

My case is, I am in Hong Kong and there are some audio clips in .asf format. I want to convert the .asf format to MP3 format so that I could save the audio clip to my Sony Clie and listen when I go to work. However, when I convert a 50 minutes .asf file (approximately 4 mb) to MP3 file, it becomes to 50 mb after it is coneverted to MP3 format. I want to know why the file size become so big and is it possible to maintain the same size after the conversion?

Thanks a lot to all and if you could give me a hand on this, it definitely helps me a lot!!!!

Best regards
Paul in Hong Kong

[daren]

You didn't mention what the MP3 settings were, so I'll make a
few assumptions....

Try using mono instead of stereo and a much lower bitrate, this
should get the filesize down (at the cost of quality, but then the
quality of the ASF file is probably pretty low for 50mins in a 4mb
file, so it shouldn't make too much difference). A lower sample
rate will also get the size down (at the cost of quality).

Make sure that your mp3 player can handle the bitrate and
sample frequency you are planning to use.

HTH
Daren.

[kenny heath]

AT THE 192 CBR SETTINGS YEILD A 7-TO-1 RATIO OF COMPRESSION FROM .WAV THAT WOULD PUT 1MIN OF MP3 TO ABOUT 1MB FILE WHERE A 1MIN WAV IS A LITTLE LESS THAN 10MB GOOD GENERAL RULE OF THUMB FOR MP3

[pachow]

Thanks for all with a quick reply and I feel the care in this website!!

Does it mean that 1 min of MP3 equal to 1mb if I convert the file from .asf to mp3? If this is the case, it match my query because the tape of the .asf is about 50 mins and now the mp3 file after conversion is 50mb! However, can I use other method to compress the mp3 file down to 4 mb? I ask this because the original .asf file is about 4mb!!

Thanks for seeing this message and give me a hand!!

[Spoon]

Try a much lower bit rate, lower frequency, mono?

[pachow]

Even mono, lower bit rate (96 per sec), the size is still at 20mb!! How can I do?? Thanks!!

[daren]

Try a lower sample rate/frequency, this will allow you to choose
lower bitrates.

Daren.

[Unregistered]

Re: asf convert to MP3 and the size is 10 times bigger!!!

I need a program which can convert from ASF to MP3

[Spoon]

Re: asf convert to MP3 and the size is 10 times bigger!!!

dBpowerAMP Music Converter with the Windows Media Audio Codec from 'codec central'

[Spoons]

Re: asf convert to MP3 and the size is 10 times bigger!!!

someone said somwhere that the original file should have the same frequency settings as the converted file. so if the original is in mono then you should also convert it to a mono frequency. so check what setting/bitrate stereo/mono the original is then convert to ogg or whatever in the same settings. but if that's still too big then yeh lower the bitrate.

[RossRoy]

Re: asf convert to MP3 and the size is 10 times bigger!!!

No Razgo, the frequency only relates to how many times per second the audio is sampled (the value expressed in Hz)

You can easily transform a Stereo signal to a Mono, you can even upgrade a mono signal to a stereo one, but both left and right channel would play the exact same thing, the file would still be fine.

Same goes for bitrate. The bitrate is totally something else.. I actually have no idea what it relates to, all I know is that a WAV is encoded at 1411 kbps, and when transcoded to a 128 kbps MP3 it sounds fine.

Same goes for bits, you can easily take a 16 bit sound file and make it an 8 bit or even 24 bit.

The problem really resides in frequency, or the number of samples taken per second. Since this is the only variable in audio file that is directly related to the time variant, changing this value without a professional frequency converter will result in an accelerated or decelerated file. Let's say for example that I have an audio file encoded at 44100 Hz (CD specs) and do a basic MP3 conversion but using 22050 Hz, well, if there's no special frequency conversion filter applied, the file will be twice as long, because there will be only 22050 sub-second units in a second, instead of the original 44100 sub-unit per second (Hz are sub-unit, they represent "cycle per seconds").

I hope this clears it up a little... And I really hope I am not mistaken in this

[Spoons]

Re: asf convert to MP3 and the size is 10 times bigger!!!

i guess what i meant was that when converting source file with "X" frequency/Hz the end file should also have the same "X" frequency/Hz for the best quality outcome. in a sense that is transcoding. so i didn't mean it can't be done but rather the output file may not be of a perfect result.

[Spoons]

Re: asf convert to MP3 and the size is 10 times bigger!!!

now i remember it was you who said it :D here: http://forum.dbpoweramp.com/showthre...ight=frequency

"So, since any audio file is frequency dependent, you need to make sure you destination frequency matches the original freuqency, in our case 8000 Hz whereas most codec defaults to the CD quality of 44100 Hz.

So, if you want to make a WAV file out of your ASF, just make sure to set the frequency to 8000 Hz or "Freq as source". "

[Spoon]

Re: asf convert to MP3 and the size is 10 times bigger!!!

All the codecs are slowly getting the 'as source' option, Wave has it in latest dMC, Ogg has it (uploading now).

[Unregistered]

Re: asf convert to MP3 and the size is 10 times bigger!!!

Do you record radio2 or 903 program??
The original file is only 16k/sec so, pick 16k/sec and 8000HZ, the file size will small as asf format..

Hi Spoon and all,

First of all, may I express my sincere thanks to Spoon since he is the first one that could provide a program to me to solve my problem!!

My case is, I am in Hong Kong and there are some audio clips in .asf format. I want to convert the .asf format to MP3 format so that I could save the audio clip to my Sony Clie and listen when I go to work. However, when I convert a 50 minutes .asf file (approximately 4 mb) to MP3 file, it becomes to 50 mb after it is coneverted to MP3 format. I want to know why the file size become so big and is it possible to maintain the same size after the conversion?

Thanks a lot to all and if you could give me a hand on this, it definitely helps me a lot!!!!

Best regards
Paul in Hong Kong