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Does OGG uses SBR?

I like to have my musics in low bitrates. Now I'm using Mp3Pro format because gives me good sound quality at 64kbps. If you know a format that have a better sound quality than Mp3Pro at 64kps (or less!) please post your opinion.

Thx:)

Does OGG uses SBR?

Reply #1
No, Ogg Vorbis doesn't use SBR as it is heavily patented. Also, as Vorbis doesn't suffer from the same hi-freq-problems as MP3 does, SBR wouldn't really be a step forward. With the release of RC4 (quite soon I think) Ogg Vorbis will offer high quality even at low bitrates.

Does OGG uses SBR?

Reply #2
Soon, there'll be AAC+ (AAC+SBR) available too.

Watch my page for news.

Regards;

Roberto.

Does OGG uses SBR?

Reply #3
Technicalities MP3:


SBR relies on sending the signal through a MDCT anaylsis filterbank and duplicating the first 8 kHz of the spectrum, then taking it along with perceptually substituted noise and reconstructing the the last 8 kHz of the spectrum. Maikmerten stated below SBR is heavily patented and that is why Vorbis codec doesn't use it which is correct. SBR was designed as alternative to that of MPEG-1 Layer 3, because the original filterbank which was a hybrid adaptive / subband transform coder had certain structural weaknesses, quantization error become greater as you split the subbands repeatedly in bandpass filter, but you increase the stationary performance. This had drawbacks though becuase, pre-echo spreads to the time domain as the IMDCT is performed resulting in pre-echo, this becomes extremely noticiable when you use smaller frame sizes at a frequency response of 44.1 kHz,  96, 80, 64 kbps, etc.

Vorbis:

Vorbis is a strictly an adaptive transform coder which doesn't use any subbands, because they are patented and have various drawbacks as well advantages. Vorbis uses a a regular MDCT anaylsis filterbank in which the filter coeffcients are calculated. Adaptive transform coders can give good stationary results closer than that of subband coder at times, yet Vorbis has a good block switching algorithm for pre-echo control although not as fast, Vorbis uses it's own window functions as well (sine based), unlike MPEG-1 Layer 3 which uses a Kaiser/Bessel derived patented window.

Vorbis in the future will implement hybrid MDCT for tonals and stationaries, as well as a Discrete Wavelet Transform for transient signals which will totally illiminate block switching all together, because the transform is well time domain oriented and well suited for transient signals this should increase resolutionary performance in stationary signals and handle transients signals better that would otherwise create pre-echo (higher temporary resolution), this will be much better for lower-bitstreams as well as audio transparency, this should be even better than using SBR.
budding I.T professional

Does OGG uses SBR?

Reply #4
RJAmorim,

Primeiramente eu também sou braisileiro. É bom ver um conterrâneo por aqui.

Segundo o link da sua página está quebrado está quebrado porque não consigo acessar. Ele está correto?

Grato:)

Does OGG uses SBR?

Reply #5
yeah the site is not available again

Does OGG uses SBR?

Reply #6
Yeah, as usual.

Wait for the surprise.

 
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