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chitunes
2009-10-09, 22:17
If I understand the specifications on the Touch web page, Apple Lossless will no longer be transcoded to a lower bitrate, as is now the case using the Duet.

Can anyone confirm that? This would be a good reason to change.

Thanks.

JJZolx
2009-10-09, 22:39
If I understand the specifications on the Touch web page, Apple Lossless will no longer be transcoded to a lower bitrate, as is now the case using the Duet.

Can anyone confirm that? This would be a good reason to change.

I don't know a great deal about Apple lossless, but that can't be true of all Apple lossless files, can it? It must depend on the sampling rate of the file. Since the Duet and SB3 are only capable of 48 kHz decoding, higher rates must be downsampled. I wouldn't think a rip of a standard redbook CD at 16 bits, 44.1 kHz would have to be downsampled just because it's encoded in Apple lossless.

The Touch is capable of natively decoding 96 kHz sampling rates.

chitunes
2009-10-10, 13:42
I don't know a great deal about Apple lossless, but that can't be true of all Apple lossless files, can it? It must depend on the sampling rate of the file. Since the Duet and SB3 are only capable of 48 kHz decoding, higher rates must be downsampled. I wouldn't think a rip of a standard redbook CD at 16 bits, 44.1 kHz would have to be downsampled just because it's encoded in Apple lossless.

The Touch is capable of natively decoding 96 kHz sampling rates.

That's what I thought. But here's the readout from the controller under More Info for the Apple Lossless file of the Beatles' "Something" RM:

"File Format: QuickTime Movie" (don't get this either, but that's how the AL files are always listed)
"Bitrate: 827 kbps VBR (Converted to 705.6 kbps ABR)"

Any ideas?

atrocity
2009-10-10, 20:29
That's what I thought. But here's the readout from the controller under More Info for the Apple Lossless file of the Beatles' "Something" RM:

"File Format: QuickTime Movie" (don't get this either, but that's how the AL files are always listed)
"Bitrate: 827 kbps VBR (Converted to 705.6 kbps ABR)"

Any ideas?

My guess (only a guess!) is that this is due to the fact that Apple Lossless isn't as efficient as FLAC. Not trying to start an OS debate, I've just noticed while testing that ALAC files are *always* bigger than FLAC. I assume SqueezeCenter is telling you the bitrate of the ALAC file, transcoding it to FLAC, then reporting the bitrate of the FLAC.

iPhone
2009-10-10, 22:11
That's what I thought. But here's the readout from the controller under More Info for the Apple Lossless file of the Beatles' "Something" RM:

"File Format: QuickTime Movie" (don't get this either, but that's how the AL files are always listed)
"Bitrate: 827 kbps VBR (Converted to 705.6 kbps ABR)"

Any ideas?

I could be completely wrong about this, but isn't this just a display bug that is already filed? I remember somebody else asking about this in the last two weeks. Can't search effiecently now on my iPhone with just Edge coverage and very little of that

Mnyb
2009-10-10, 23:13
It's behaves in a similar way when SOX is used to transcode between 24/96 to 24/48 displaying bogus bitrates ? if it is what your are searching for.

IMHO remove that info don't display anything if its incorrect, just show "transcoded" flac>flac, alc>flac mp4>mp3 , WMA>flac or whatever is going on it would give way more useful info .

The culprit is that The vbr rate can only be retrieved for a file after it's coded, it a statistic ?

As transcoding is done on the fly you don't realy now until after the fact so the devs have opted to show some "typical" rates for that kind of file ? in some cases it s very near the real rate in some cases a bad gues, just ignore enjoy the music :)

funkstar
2009-10-11, 06:26
That's what I thought. But here's the readout from the controller under More Info for the Apple Lossless file of the Beatles' "Something" RM:

"File Format: QuickTime Movie" (don't get this either, but that's how the AL files are always listed)
"Bitrate: 827 kbps VBR (Converted to 705.6 kbps ABR)"

Any ideas?
iPhone is right, currently there is no way to get the actual bitrate from the transcoding process, so they just show a rough estimated average for a Flac file (roughly half the bitrate of a CD).

that is a lossless bitrate, so don't worry about it. I would only be concerned if it was 320kbit or lower, which would mean it is being transcoded to a lossy format by mistake.

chitunes
2009-10-11, 11:42
iPhone is right, currently there is no way to get the actual bitrate from the transcoding process, so they just show a rough estimated average for a Flac file (roughly half the bitrate of a CD).

that is a lossless bitrate, so don't worry about it. I would only be concerned if it was 320kbit or lower, which would mean it is being transcoded to a lossy format by mistake.

Thanks everyone. You addressed my main concern that the lossless quality is not diminished.

JJZolx
2009-10-11, 13:53
iPhone is right, currently there is no way to get the actual bitrate from the transcoding process, so they just show a rough estimated average for a Flac file (roughly half the bitrate of a CD).

What are you calling 'actual' bitrate? The bitrates shown by SbS aren't estimates, they're merely the rate at which the data needs to stream based on file size and track time.

For redbook audio, 44.1 kHz 16 bit stereo, the uncompressed bitrate is:

44,100 * 16 * 2 / 1000 = 1411 kbps

The computed bitrate in SbS for lossless files is:

file_size_in_bytes * 8_bits_per_byte / track_time_in_seconds / 1000

For example, a track of 8:48 with a file size of 60,023,175 bytes:

60,023,175 * 8 / 528 / 1000 = 909 kbps

sebp
2009-10-11, 13:57
I don't know a great deal about Apple lossless, but that can't be true of all Apple lossless files, can it?
AFAIK, Apple Lossless, like WMA Lossless, isn't a format supported natively by the IP3K Squeezeboxes.
It needs to be converted to something else the SB can play.

funkstar
2009-10-11, 15:25
What are you calling 'actual' bitrate? The bitrates shown by SbS aren't estimates, they're merely the rate at which the data needs to stream based on file size and track time.
By 'actual' bitrate, I mean the real rate of bits being sent to the player for tht track, either that that time (averaged over that second) or for the whole track.

A Controller or SB3 will display "705.6 kbps ABR" when transcoding regardless of the actual bit rate of the data being sent. It's possible a FLAC could hit that exactly, but unlikely. And as the ALAC in question in Post 3 is "827 kbps VBR" I would expect the FLAC to be closer to that than 705.6.

chitunes
2009-10-11, 16:33
AFAIK, Apple Lossless, like WMA Lossless, isn't a format supported natively by the IP3K Squeezeboxes.
It needs to be converted to something else the SB can play.


OK - that brings me back to my original question. It appears from the specifications for the Touch that it supports Apple Lossless as a native format no longer requiring transcoding. Pasted from the Touch website:

Technical Specifications
Audio
Audio formats
MP3, FLAC, WAV, AIFF, WMA, Ogg Vorbis, AAC, Apple Lossless
WMA Lossless, APE, MPC and WavPack supported through transcoding
Some formats may require additional software installation

Am I reading that correctly?

andyg
2009-10-11, 16:42
On Oct 11, 2009, at 7:33 PM, chitunes wrote:

>
> sebp;470777 Wrote:
>> AFAIK, Apple Lossless, like WMA Lossless, isn't a format supported
>> natively by the IP3K Squeezeboxes.
>> It needs to be converted to something else the SB can play.
>
>
> OK - that brings me back to my original question. It appears from the
> specifications for the Touch that it supports Apple Lossless as a
> native
> format no longer requiring transcoding. Pasted from the Touch
> website:
>
> Technical Specifications
> Audio
> Audio formats
> MP3, FLAC, WAV, AIFF, WMA, Ogg Vorbis, AAC, Apple Lossless
> WMA Lossless, APE, MPC and WavPack supported through transcoding
> Some formats may require additional software installation
>
> Am I reading that correctly?

We intend to support ALAC natively but we don't have the codec working
yet.

chitunes
2009-10-11, 16:57
On Oct 11, 2009, at 7:33 PM, chitunes wrote:

>
> sebp;470777 Wrote:
>> AFAIK, Apple Lossless, like WMA Lossless, isn't a format supported
>> natively by the IP3K Squeezeboxes.
>> It needs to be converted to something else the SB can play.
>
>
> OK - that brings me back to my original question. It appears from the
> specifications for the Touch that it supports Apple Lossless as a
> native
> format no longer requiring transcoding. Pasted from the Touch
> website:
>
> Technical Specifications
> Audio
> Audio formats
> MP3, FLAC, WAV, AIFF, WMA, Ogg Vorbis, AAC, Apple Lossless
> WMA Lossless, APE, MPC and WavPack supported through transcoding
> Some formats may require additional software installation
>
> Am I reading that correctly?

We intend to support ALAC natively but we don't have the codec working
yet.

Thanks for the quick response. Any idea if you'll have it working by the release date or another target date?

I'm guessing if not, a firmware update will be made available.

andyg
2009-10-11, 18:06
On Oct 11, 2009, at 7:57 PM, chitunes wrote:

>
> andyg;470847 Wrote:
>> On Oct 11, 2009, at 7:33 PM, chitunes wrote:
>>
>>>
>>> sebp;470777 Wrote:
>>>> AFAIK, Apple Lossless, like WMA Lossless, isn't a format supported
>>>> natively by the IP3K Squeezeboxes.
>>>> It needs to be converted to something else the SB can play.
>>>
>>>
>>> OK - that brings me back to my original question. It appears from
>> the
>>> specifications for the Touch that it supports Apple Lossless as a
>>> native
>>> format no longer requiring transcoding. Pasted from the Touch
>>> website:
>>>
>>> Technical Specifications
>>> Audio
>>> Audio formats
>>> MP3, FLAC, WAV, AIFF, WMA, Ogg Vorbis, AAC, Apple Lossless
>>> WMA Lossless, APE, MPC and WavPack supported through transcoding
>>> Some formats may require additional software installation
>>>
>>> Am I reading that correctly?
>>
>> We intend to support ALAC natively but we don't have the codec
>> working
>>
>> yet.
>
> Thanks for the quick response. Any idea if you'll have it working by
> the release date or another target date?
>
> I'm guessing if not, a firmware update will be made available.

I can't say for sure.

chitunes
2009-10-11, 18:35
On Oct 11, 2009, at 7:57 PM, chitunes wrote:

>
> andyg;470847 Wrote:
>> On Oct 11, 2009, at 7:33 PM, chitunes wrote:
>>
>>>
>>> sebp;470777 Wrote:
>>>> AFAIK, Apple Lossless, like WMA Lossless, isn't a format supported
>>>> natively by the IP3K Squeezeboxes.
>>>> It needs to be converted to something else the SB can play.
>>>
>>>
>>> OK - that brings me back to my original question. It appears from
>> the
>>> specifications for the Touch that it supports Apple Lossless as a
>>> native
>>> format no longer requiring transcoding. Pasted from the Touch
>>> website:
>>>
>>> Technical Specifications
>>> Audio
>>> Audio formats
>>> MP3, FLAC, WAV, AIFF, WMA, Ogg Vorbis, AAC, Apple Lossless
>>> WMA Lossless, APE, MPC and WavPack supported through transcoding
>>> Some formats may require additional software installation
>>>
>>> Am I reading that correctly?
>>
>> We intend to support ALAC natively but we don't have the codec
>> working
>>
>> yet.
>
> Thanks for the quick response. Any idea if you'll have it working by
> the release date or another target date?
>
> I'm guessing if not, a firmware update will be made available.

I can't say for sure.

When the codec is ready, I'd want to upgrade from my Duet. How can I find out if and when?

Thanks.

radish
2009-10-11, 19:08
Watch this space. Come release time, I'm sure the spec page will be updated if ALAC support isn't available.

funkstar
2009-10-12, 01:55
When the codec is ready, I'd want to upgrade from my Duet. How can I find out if and when?

Thanks.

There is also a bug listed for this:
https://bugs.slimdevices.com/show_bug.cgi?id=12421

Create an account and you will be able to CC yourself to it, or vote for it and be notified of updates.

gorman
2009-10-14, 01:44
Watch this space. Come release time, I'm sure the spec page will be updated if ALAC support isn't available.I couldn't care less, in all honesty, but if Logitech is not sure about supporting natively ALAC at launch it should do well by stating it clearly on the product page. There's no shame in stating something like

----------------------------------------------
ALAC*

*Native support might be added post-launch through a firmware update
----------------------------------------------

Logitech/Slimdevices has a good track record for keeping promises, they should bank on it and being transparent about the ongoing development process.

Smells like unintentional false advertising to me, otherwise. No malice, but it's not right.

chitunes
2009-10-14, 20:31
There is also a bug listed for this:
https://bugs.slimdevices.com/show_bug.cgi?id=12421

Create an account and you will be able to CC yourself to it, or vote for it and be notified of updates.

Done. Thanks for the tip. Can't believe mine was the first vote. Guess I won't be seeing native ALAC anytime soon!

Thanks for all the input

radish
2009-10-15, 07:02
Smells like unintentional false advertising to me, otherwise. No malice, but it's not right.
IMHO it's false advertising once the product is on sale. Until then, and this feature is present or not, it's all just conjecture. It's not exactly unusual for a product's final specs to differ from the originally announced ones.

gorman
2009-10-18, 02:01
I just wish to stress that I wasn't in any way implying malice, hence the "unintentional" bit.

Edit: although now ALAC native support is mentioned in the official product page, with price, buy me now and all the regular stuff.
Has it been added?

radish
2009-10-19, 08:41
I just wish to stress that I wasn't in any way implying malice, hence the "unintentional" bit.

Edit: although now ALAC native support is mentioned in the official product page, with price, buy me now and all the regular stuff.
Has it been added?

My understanding is that it was there, then it was discovered to be buggy and disabled. The plan is to add it back when there's time in the schedule - more details on the bugzilla link previously provided.

metalbob
2009-11-23, 07:18
When transcoding from ALAC to FLAC on any Squeezebox device (I don't have one yet, but waiting for the Touch release), is there any noticeable quality loss or any performance issues?