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Need info about the MELP bitstream format..?

Started by Khubaib February 24, 2004
Dear membes
I need to know the bitstream format of the MELP's 54 bit frame.?. I
know what are the different bits (the number of bits for different
parameters) in the bitstream, e.g. this is the 54 bit format
Pitch index 7
Jitter flag 1
Bandpass voicing decision 4x1
Gain for second half of frame 5
Gain for first half of frame 3
LSP frequencies (10 line spectrum pairs) 25
Fourier magnitudes (10 harmonies) 8
Sync bit 1
Total 54
What i need to know is, what are the LSB's and what are the MSB's..?
e.g. Where is pitch index lies, at the LSB side, or the MSB side..?.
Thanx
Khubaib



Hi,
See the pdf http://65.90.39.159/html/voicecompress.pdf
if you havent seen it already. I think the info on page 6 might be of help
Regards,
Abhijeet Khubaib <> wrote:
Dear membes
I need to know the bitstream format of the MELP's 54 bit frame.?. I
know what are the different bits (the number of bits for different
parameters) in the bitstream, e.g. this is the 54 bit format
Pitch index 7
Jitter flag 1
Bandpass voicing decision 4x1
Gain for second half of frame 5
Gain for first half of frame 3
LSP frequencies (10 line spectrum pairs) 25
Fourier magnitudes (10 harmonies) 8
Sync bit 1
Total 54
What i need to know is, what are the LSB's and what are the MSB's..?
e.g. Where is pitch index lies, at the LSB side, or the MSB side..?.
Thanx
Khubaib

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Khubaib-

> I need to know the bitstream format of the MELP's 54 bit frame.?. I
> know what are the different bits (the number of bits for different
> parameters) in the bitstream, e.g. this is the 54 bit format
> Pitch index 7
> Jitter flag 1
> Bandpass voicing decision 4x1
> Gain for second half of frame 5
> Gain for first half of frame 3
> LSP frequencies (10 line spectrum pairs) 25
> Fourier magnitudes (10 harmonies) 8
> Sync bit 1
> Total 54
> What i need to know is, what are the LSB's and what are the MSB's..?
> e.g. Where is pitch index lies, at the LSB side, or the MSB side..?.

The bits u see above are *after* codebook processing -- u have to back up before
codebook quantization in the encode side of the algorithm to clearly see output
parameters.

-Jeff