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View Full Version : Uncompressed @ 1411, 1412, and 1378 Kbps ?



Chris CA
08-13-2011, 04:30 PM
Hi Guys - I've ripped some tracks in Uncompressed FLAC. When viewing these files with different programs the Kbps are displayed differently for the exact same file. For example J River Media Center displays a track at 1412 Kbps and my Linux server displays the same track at 1378 Kbps.

Two Questions:

1. Shouldn't uncompressed rips always be 1411?

2. Why are different applications displaying different Kbps rates for the same file?

Thanks for your time and the help.


Chris Connaker

Founder
Computer Audiophile

JDCFH
08-13-2011, 05:24 PM
Hi Guys - I've ripped some tracks in Uncompressed FLAC. When viewing these files with different programs the Kbps are displayed differently for the exact same file. For example J River Media Center displays a track at 1412 Kbps and my Linux server displays the same track at 1378 Kbps.

Two Questions:

1. Shouldn't uncompressed rips always be 1411?

2. Why are different applications displaying different Kbps rates for the same file?

Thanks for your time and the help.


Chris Connaker

Founder
Computer Audiophile

Not sure why different programs are showing different bit rate but i do know that not all lossless audio will be a constant bit rate of 1411Kbps.

When i rip to ALAC my CD's are variable bit rates and lossless :thumbup:

Spoon
08-13-2011, 06:04 PM
I am guessing it is just rounding errors, some software would not even tag the ID tag into account when determining the bit rate....

mkmkatemail
02-01-2012, 02:36 PM
Hi Guys - I've ripped some tracks in Uncompressed FLAC. When viewing these files with different programs the Kbps are displayed differently for the exact same file. For example J River Media Center displays a track at 1412 Kbps and my Linux server displays the same track at 1378 Kbps.

Two Questions:

1. Shouldn't uncompressed rips always be 1411?

2. Why are different applications displaying different Kbps rates for the same file?

Thanks for your time and the help.


Chris Connaker

Founder
Computer Audiophile

Hi Chris,

Kbps stands for kilobits per second. What's going on here is that one program counts one kilo-bit as 1024 bits and the other as 1000 bits (1411 / 1.024 ~= 1378)
Your rips are obviously lossless, count with me:
CD quality means 44.100 kHz sampling rate (44100 samples per second), 16-bit resolution (two bytes per sample), stereo (twice as much)
44100 * 2 * 2 = 176400 BYTES per second -> 176400 * 8 = 1411200 BITS per second (here's your 1411 kbps) or 1411200 / 1024 = 1378.125 kbps

Hope this makes sence.
Cheers Michal

Chris CA
02-01-2012, 02:46 PM
Hi Chris,

Kbps stands for kilobits per second. What's going on here is that one program counts one kilo-bit as 1024 bits and the other as 1000 bits (1411 / 1.024 ~= 1378)
Your rips are obviously lossless, count with me:
CD quality means 44.100 kHz sampling rate (44100 samples per second), 16-bit resolution (two bytes per sample), stereo (twice as much)
44100 * 2 * 2 = 176400 BYTES per second -> 176400 * 8 = 1411200 BITS per second (here's your 1411 kbps) or 1411200 / 1024 = 1378.125 kbps

Hope this makes sence.
Cheers Michal

Understood Michal. Thank you very mich for the straight forward math / explanation. It makes total sense.

I'll assume 1412 us just a rounding error by the application.

Thanks again.

Chris