Hi,
1)I wanted to how many subbands are there in Mpeg4 AAC.
2) Are the subbands and scale factor bands same ?
3) Can Joint stereo coding, PNS and TNS be applied to all subbands or only some parts of subbands.
Please reply immediately.
Thanks and Regards
Shreya
Full Version: Subbands in Mpeg4 AAC
1. 1024 subbands (MDCT Coefficients).
2. No, the number of scale factor bands depends on sampling frequency and is 51 (I think) for 44100Hz. The number of subbands they contain roughly corresponds to the Bark scale.
3. They can all be applied to selective scale factor bands.
/Pontus
2. No, the number of scale factor bands depends on sampling frequency and is 51 (I think) for 44100Hz. The number of subbands they contain roughly corresponds to the Bark scale.
3. They can all be applied to selective scale factor bands.
/Pontus
QUOTE(squid @ Jan 7 2005, 01:37 PM)
1. 1024 subbands (MDCT Coefficients).
2. No, the number of scale factor bands depends on sampling frequency and is 51 (I think) for 44100Hz. The number of subbands they contain roughly corresponds to the Bark scale.
3. They can all be applied to selective scale factor bands.
/Pontus
2. No, the number of scale factor bands depends on sampling frequency and is 51 (I think) for 44100Hz. The number of subbands they contain roughly corresponds to the Bark scale.
3. They can all be applied to selective scale factor bands.
/Pontus
Hi,
On what part of spectral band the joint stereo,TNS and PNS are applied ?
Thanks and Regards
Shreya
MS, PNS and TNS are (selectively) applied to individual scale factor bands, so each scale factor band can have an independent configuration of MS/PNS/TNS. For example stereo correlation is typically larger at lower subbands and in this case MS can be turned on for the lower scale factor bands and turned off for the higher scale factor bands.
/Pontus
/Pontus
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