Bitrates and Compression
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
Text is available under the terms of the DAISY Consortium Intellectual Property Policy, Licensing, and Working Group Process.
Text is available under the terms of the DAISY Consortium Intellectual Property Policy, Licensing, and Working Group Process.
