VS1033 Datasheet, PDF (26/70 Pages) List of Unclassifed Manufacturers – MP3/AAC/WMA/MIDI AUDIO CODEC

VLSI
Solution ^y
VS1033a PRELIMINARY
VS1033A
8. FUNCTIONAL DESCRIPTION
8.2.4 Supported AAC (ISO/IEC 13818-7) Formats
VS1033 decodes MPEG2-AAC-LC-2.0.0.0 and MPEG4-AAC-LC-2.0.0.0 streams. This means that the
low complexity profile with maximum of two channels can be decoded. If a stream contains more than
one element and/or element type, you can select which one to decode from the 16 single-channel, 16
channel-pair, and 16 low-frequency elements. The default is to select the first one that appears in the
stream.
Dynamic range control (DRC) is supported and can be controlled by the user to limit or enhance the
dynamic range of the material that has DRC information.
Both Sine window and Kaiser-Bessel-derived window are supported.
For MPEG4 pseudo-random noise substitution (PNS) is supported. Short frames (120 and 960 samples)
are not supported.
For AAC the streaming ADTS format is recommended. This format allows easy rewind and fast forward
because resynchronization is easily possible.
In addition to ADTS (.aac), MPEG2 ADIF (.aac) and MPEG4 AUDIO (.mp4 / .m4a) files are played,
but these formats are less suitable for rewind and fast forward operations. You can still implement these
features by using the safe jump points table and seek mechanism provided, or using slightly less robust
but much easier automatic resync mechanism (see Section 9.9).
Note: To be able to play the .mp4 and .m4a files, the mdat chunk must be the last chunk in the file.
AAC¹²:
Samplerate / Hz
Maximum Bitrate kbit/s - for 2 channels
≤96 132 144 192 264 288 384 529 576
48000 + + + + + + + + +
44100 + + + + + + + +
32000 + + + + + + +
24000 + + + + + +
22050 + + + + +
16000 + + + +
12000 + + +
11025 + +
8000 +
1 _{64000 Hz, 88200 Hz, and 96000 Hz AAC files are played but with wrong speed.}
2 _{Also all variable bitrate (VBR) formats are supported. Note that the table gives the maximum bitrate}
allowed for two channels for a specific sample rate as defined by the AAC specification. The decoder
does not actually have a lower or upper limit.
Version 0.6, 2005-01-05
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