Bitrates and Compression

Original Author(s): Lynn Leith
Depending upon the codec and compression level selected, a variety of file sizes can be achieved. The following table shows the disk space requirements, along with a comparison of total time per CD. Note that it is possible to add external codecs such as MPEG 3 to the list of available codecs in lpStudio/Pro and Sigtuna DAR 3.

Table of bitrates and compression ratio

Format/CoDec Kbits/sec Bits/sec MB/hour Hours/CD (625 MB)
PCM 16 bit stereo 44 KHz (CD-DA) 1411 1411200 605.62 1.03
PCM 16 bit mono 44 KHz 706 705600 302.81 2.06
PCM 16 bit mono 22 KHz 353 352800 151.41 4.13
DVI/IMA ADPCM (4 bit, mono) 44 KHz 176 176400 75.70 8.26
DVI/IMA ADPCM (4 bit, mono) 22 Khz 88 88200 37.85 16.51
DVI/IMA ADPCM (4 bit, mono) 11 KHz 44 44100 18.93 33.02
MPEG-1 / MPEG-2, Layer 2 / 3 (mono)
(quality defined by layer, bit rate and sampling frequency)
96 96000 41.20 15.17
64 64000 27.47 22.76
56 56000 24.03 26.01
48 48000 20.60 30.34
40 40000 17.17 36.41
32 32000 13.73 45.51
24 24000 10.30 60.68

WARNING: Care should be taken to select the lowest amount of compression that is required. One drawback to audio compression is that as the amount of compression is increased, the audio quality decreases.

Depending upon the codec and compression level selected, a variety of file sizes can be achieved. The following table shows the disk space requirements, along with a comparison of total time per CD. Note that it is possible to add external codecs such as MPEG 3 to the list of available codecs in lpStudio/Pro and Sigtuna DAR 3.

Table of bitrates and compression ratio

Format/CoDec Kbits/sec Bits/sec MB/hour Hours/CD (625 MB)
PCM 16 bit stereo 44 KHz (CD-DA) 1411 1411200 605.62 1.03
PCM 16 bit mono 44 KHz 706 705600 302.81 2.06
PCM 16 bit mono 22 KHz 353 352800 151.41 4.13
DVI/IMA ADPCM (4 bit, mono) 44 KHz 176 176400 75.70 8.26
DVI/IMA ADPCM (4 bit, mono) 22 Khz 88 88200 37.85 16.51
DVI/IMA ADPCM (4 bit, mono) 11 KHz 44 44100 18.93 33.02
MPEG-1 / MPEG-2, Layer 2 / 3 (mono)
(quality defined by layer, bit rate and sampling frequency)
96 96000 41.20 15.17
64 64000 27.47 22.76
56 56000 24.03 26.01
48 48000 20.60 30.34
40 40000 17.17 36.41
32 32000 13.73 45.51
24 24000 10.30 60.68

WARNING: Care should be taken to select the lowest amount of compression that is required. One drawback to audio compression is that as the amount of compression is increased, the audio quality decreases.

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This page was last edited by LLeith on Tuesday, August 10, 2010 14:41
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