
White Paper M600
Media formats
Audio formats
Format | Description |
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| Advanced Audio Coding. AAC is the latest audio coding standard, defined in the |
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| quality than MP3 at the same bit rate, or for the same audio quality it uses a 30 per cent |
| lower bit rate. It supports the coding of multichannel audio, with up to 48 main chan- |
| nels and 16 |
| trade off between quality, memory and processing power requirements. They include: |
| Main Profile (MP), Low Complexity (LC) and Scalable Sampling Rate (SSR). The Media |
| player can play |
| The Sound recorder use the |
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| Adaptive Multi Rate. |
| for the mobile environment, requiring as little as 4.75 Kbps bandwidth. |
| to convey voice recordings in MMS, 3GPP video clips or streams. M600 records AMR |
| using 12.2 Kbps with a sample rate of 8 kHz. |
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AU | Similar to WAV, this is an audio format commonly used in the Macintosh, Unix and |
| Java™ worlds. It is not commonly used for content on mobile devices. |
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iMelody | A format commonly used for monophonic ringtones. (M600 ringtones can use up to 40 |
| voices.) |
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MIDI | Musical Instrument Digital Interface. |
| MIDI is not a recording of music, but a description which enables a local synthesizer to |
| play the music from the instructions included in the MIDI file. Since a MIDI file only rep- |
| resents player information, it is far more concise than formats that store the sound |
| directly. An advantage is very small file sizes. A disadvantage is the lack of specific |
| sound control. MIDI is ideal for polyphonic ringtones. (M600 ringtones can use up to 40 |
| voices.) |
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| adapted for mobile phones and other portable products. The objective is to secure |
| interoperability between products with different sound capabilities. |
| Initial recommendations for using |
| separate document, Scalable Polyphony MIDI Device |
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MP3 | MP3 is the file extension for MPEG audio layer 3. Layer 3 is one of three coding |
| schemes (layer 1, layer 2 and layer 3) for the compression of audio signals. Layer 3 |
| uses a very efficient compression method, removing all irrelevant parts of a sound sig- |
| nal that the human ear cannot perceive. The result is, CD digital audio (CDDA) is con- |
| verted to MP3 with almost untouched quality, compressed by a factor of around 12. |
| The high compression of audio in MP3 files makes them relatively small, though MP3 |
| files can be created with different size and quality compromises. The small file size, |
| together with the excellent sound quality, are the main reasons for the |
| massive popularity when sharing music over the Internet. |
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RMF | Rich Music FormatTM. A file format developed by Beatnik combining the compact size |
| of MIDI files with the high quality of sampled sound. |
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36 | February 2006 |