JJZolx wrote: 
> You don't say which players you've tried without success.

Transporter, Squeezeplay and Radio...

JJZolx wrote: 
> One thing I've noticed about 24-bit FLAC is that the compression ratios
> tend to be much worse than their 16-bit counterparts, so that will
> compound the problem.

Yes. I think there is a reason for this due to the nature of the UPnP
HTTP streaming protocols.

When a UPnP media Control Point starts pushing a hi-res stream, it first
starts a transcoding process to convert (say) the original source format
(say WAV or AIF) to FLAC on the fly, and at the say time it must start
pushing the first few bytes of the stream to the player. In other words,
it starts pushing the stream before it knows the final length of the
stream.

Now the nature of HTTP streaming is that the server must send an HTTP
ContentLength header in its first response. But since it does not yet
know the final length of the transcoded stream it must therefore offer a
guessed value. In the case of FLAC, the easiest guess is ContentLength
:= Duration x Sample Rate x BytesPerSample x Channels x Compression
Ratio. However when transcoding FLAC the Compression Ratio is variable
depending on the content. Therefore very often such applications set the
FLAC transcoder so it applies zero compression. That way, you can send
ContentLength := Duration x Sample Rate x BytesPerSample x Channels x
1.0 at the start of the stream push process...

PS oddly enough, another advantage of zero compression FLACs is that it
requires less CPU power in the players to decode and play it. (But
obviously the other side of the coin is, as we see here, that it
requires more network throughput in the players to fetch the stream in
the first place. A classic trade- off...


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