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wavpack -b1520

I know that's very strange using such high bitrate (especially if the source is mostly CDDA) of 1520 kbps.

But recently we tried a network stream with wavpack 4.40 and it worked! We tried out how high the bitrate can be in our connection without puffer. By testing this, I simply got the question: if you manually select the wavpack bitrate (-b1520), is it then also lossless like the normal lossless modes?

thx for response.

EDIT: there's no real stream of 1520 kbps then, only bits which are needed (seems to be the same as in normal mode), but the -bXXX options only allow our stream to work. Set the parameters to normal we can't get a stream... that's a bit strange!
FB2K,APE&LAME

wavpack -b1520

Reply #1
I know that's very strange using such high bitrate (especially if the source is mostly CDDA) of 1520 kbps.

But recently we tried a network stream with wavpack 4.40 and it worked! We tried out how high the bitrate can be in our connection without puffer. By testing this, I simply got the question: if you manually select the wavpack bitrate (-b1520), is it then also lossless like the normal lossless modes?

If you select -b1520 then you should always get a lossless output, and the bitrate would be almost the same as selecting regular lossless mode. When the file is done, WavPack will even report the compression as lossless if there were, in fact, no samples different. With quieter samples, you can specify lower bitrates and still get lossless (although you have to specify a rate somewhat higher than the pure lossless bitrate).

However, the decoder will always report these files as lossy, because it cannot know if the conversion was lossless or not. If you add MD5 sums (-m) you can tell on decode.



EDIT: there's no real stream of 1520 kbps then, only bits which are needed (seems to be the same as in normal mode), but the -bXXX options only allow our stream to work. Set the parameters to normal we can't get a stream... that's a bit strange!

I don't understand why this would happen. WavPack should behave the same with -b1520 as without.

The only difference is that normal mode would be somewhat faster. You could try -h or -x to slow it down a little.

wavpack -b1520

Reply #2
why wouldn't you just encode lossless again?

 

wavpack -b1520

Reply #3
Quote
If you select -b1520 then you should always get a lossless output, and the bitrate would be almost the same as selecting regular lossless mode. When the file is done, WavPack will even report the compression as lossless if there were, in fact, no samples different. With quieter samples, you can specify lower bitrates and still get lossless (although you have to specify a rate somewhat higher than the pure lossless bitrate).

However, the decoder will always report these files as lossy, because it cannot know if the conversion was lossless or not. If you add MD5 sums (-m) you can tell on decode.


I see, thanks

Quote
I don't understand why this would happen. WavPack should behave the same with -b1520 as without.

The only difference is that normal mode would be somewhat faster. You could try -h or -x to slow it down a little.


The stream is usually made for a specified bandwith which is needed. So in the config window of the stream connection is an option where you manually can select the size of the bits which are needed for stream. In fact, if we type in 1520 kbps then, there's a constant bitrate usage of 1520 kbps then, where the wavpack stream is in. The configuration is looking for this bitrate in the parameters set for the encoder (usually it's an CBR mp3 stream, but we could modify it for other encoders, too) But playing then the PLS data, foobar shows the normal bitrate of wavpack. Maybe we've got to look for a better way to stream.

thx for your replies.
FB2K,APE&LAME

 
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