Alliedassault - View Single Post

Mr.Buttocks · 01-16-2005, 08:58 PM

[quote="Kenny Banya":272f5]
educate me on bitrates plz freak:[/quote:272f5]

I covered all this at Uni but I'm not going to try to put it into my own words at 2:53am, I'll spaz it up. It'll make more sense if you read this.....

[quote=Wikipedia]
Bit rate

The bit rate, i.e. the number of binary digits streamed per second, is variable for MP3 files. The general rule is that the higher the bitrate, the more information is included from the original sound file, and thus the higher the quality of played back audio. In the early days of MP3 encoding, a fixed bit rate was used for the entire file.

Bit rates available in MPEG-1 layer 3 are 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s (103 bits per second), and the available sample frequencies are 32, 44.1 and 48 kHz. 44.1 kHz is almost always used as this is the audio CD frequency, and 128 Kbit has become the de facto "good enough" standard. MPEG-2 and (non-official) MPEG-2.5 adds more bitrates: 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kbit/s.

Variable bit rates are also possible. Audio in MP3 files are divided into frames which all have a bitrate marker, so it is possible to change the bitrate dynamically as the file is played. This was not originally done, but VBR is in extensive use today. This technique makes it possible to use more bits for parts of the sound with high dynamics (much "sound movement") and less bits for parts with low dynamics, increasing quality and decreasing storage space further. This method compares to a sound activated tape recorder which saves the tape space from when silence was prevalent for the times when sound is being heard. Some encoders utilize this technique to a great extent.[/quote]

Other mp3 info here: [url="http://en.wikipedia.org/wiki/MP3"]http://en.wikipedia.org/wiki/MP3[/url]

	(#21)
Mr.Buttocks is Offline Major General Posts: 12,924 Join Date: Feb 2004 Location: The Continent of Africa	01-16-2005, 08:58 PM [quote="Kenny Banya":272f5] educate me on bitrates plz freak:[/quote:272f5] I covered all this at Uni but I'm not going to try to put it into my own words at 2:53am, I'll spaz it up. It'll make more sense if you read this..... [quote=Wikipedia] Bit rate The bit rate, i.e. the number of binary digits streamed per second, is variable for MP3 files. The general rule is that the higher the bitrate, the more information is included from the original sound file, and thus the higher the quality of played back audio. In the early days of MP3 encoding, a fixed bit rate was used for the entire file. Bit rates available in MPEG-1 layer 3 are 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s (103 bits per second), and the available sample frequencies are 32, 44.1 and 48 kHz. 44.1 kHz is almost always used as this is the audio CD frequency, and 128 Kbit has become the de facto "good enough" standard. MPEG-2 and (non-official) MPEG-2.5 adds more bitrates: 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kbit/s. Variable bit rates are also possible. Audio in MP3 files are divided into frames which all have a bitrate marker, so it is possible to change the bitrate dynamically as the file is played. This was not originally done, but VBR is in extensive use today. This technique makes it possible to use more bits for parts of the sound with high dynamics (much "sound movement") and less bits for parts with low dynamics, increasing quality and decreasing storage space further. This method compares to a sound activated tape recorder which saves the tape space from when silence was prevalent for the times when sound is being heard. Some encoders utilize this technique to a great extent.[/quote] Other mp3 info here: [url="http://en.wikipedia.org/wiki/MP3"]http://en.wikipedia.org/wiki/MP3[/url]