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64 kbps listening test 2005
Reply #150
I think it'd be better to conduce an 128 kbps test once LAME 3.97 and Nero AAC are out.

64 kbps listening test 2005
Reply #151
I vote for WMA9 Pro and Sdt because:
1) Not the same codec
2) wma9 pro was never tested to 64 Kbps
3) hardware compatibility is not a problem : HE-AAC or MP3Pro are not compatible with hardware
4) wma9 sdt vs wma9 pro fight is very interessing

WMA9 Standard setting
I think that for very bitrate the best setting could be that:
cscript.exe wmcmd.vbs -a_codec WMA9STD -a_mode 4 -a_setting 64_44_2 -a_peakbitrate 96000 -a_peakbuffer 5000 -input C:\Audio -output C:\Audio

-> Max bitrate is 96 Kbps : lower variability
-> Max buffer = 5 sec : lower variability
In fact with these setting wma9 is between real VBR and real CBR and IMO it's better for overall quality at very low bitrate

WMA9 Pro sample
In theory it's impossible to make WMA9Pro with exact bitrate at 64Kbps (no profil for 64 Kbps target bitrate) but if you want I can make these encoding with exactly 64 Kbps for each sample in two pass mode.

  • rjamorim
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64 kbps listening test 2005
Reply #152
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2) wma9 pro was never tested to 64 Kbps


It is not even meant to be used at 64kbps.

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3) hardware compatibility is not a problem : HE-AAC or MP3Pro are not compatible with hardware


HE AAC is actually playable on some cell phones. And MP3pro is playable on several Thomson/RCA devices, among other brands.

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4) wma9 sdt vs wma9 pro fight is very interessing


It is not a fight. Not even Microsoft is interested in that fight! For them, WMA Std is the consumer codec, meant to be used for CDDA resolution at 64kbps. WMA Pro is the professional codec meant to be used at high resolutions, multichannel streams, at bitrates higher than 128kbps.

Quote
WMA9 Standard setting
I think that for very bitrate the best setting could be that:
cscript.exe wmcmd.vbs -a_codec WMA9STD -a_mode 4 -a_setting 64_44_2 -a_peakbitrate 96000 -a_peakbuffer 5000 -input C:\Audio -output C:\Audio

-> Max bitrate is 96 Kbps : lower variability
-> Max buffer = 5 sec : lower variability
In fact with these setting wma9 is between real VBR and real CBR and IMO it's better for overall quality at very low bitrate


Settings tweaking IST EVUL.

Quote
WMA9 Pro sample
In theory it's impossible to make WMA9Pro with exact bitrate at 64Kbps (no profil for 64 Kbps target bitrate)[a href="index.php?act=findpost&pid=319462"][{POST_SNAPBACK}][/a]


There you go. WMA Pro is not meant to be encoded at 64kbps.
  • Last Edit: 11 August, 2005, 08:18:45 PM by rjamorim
Get up-to-date binaries of Lame, AAC, Vorbis and much more at RareWares:
http://www.rarewares.org

  • pieroxy
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64 kbps listening test 2005
Reply #153
Quote
Regarding samples, I have enough now, thank you. It's a bit hard to decide which ones to use, since almost all of them are more or less killer samples.
[{POST_SNAPBACK}][/a]


Beware of the bias of testing only killer samples. Comparing codecs on killer samples will only give you a hint on how they perform... on killer samples. Not on regular music. See [a href="http://www.hydrogenaudio.org/forums/index.php?showtopic=36184]here[/url] for a thread on the subject.

  • level
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64 kbps listening test 2005
Reply #154
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Beware of the bias of testing only killer samples. Comparing codecs on killer samples will only give you a hint on how they perform... on killer samples. Not on regular music. See here for a thread on the subject.
[a href="index.php?act=findpost&pid=319563"][{POST_SNAPBACK}][/a]

Not necessarily. You remember that many killer samples (in particular here in this thread) are only regular music. In other words, are situations of the real life. Tuning any encoder with "difficult parts of music" (killer samples) in order to do it more robust is the way as HA has managed to improve the performance of the encoders.

  • xmixahlx
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64 kbps listening test 2005
Reply #155
Quote
Beware of the bias of testing only killer samples. Comparing codecs on killer samples will only give you a hint on how they perform... on killer samples. Not on regular music. See here for a thread on the subject.
[a href="index.php?act=findpost&pid=319563"][{POST_SNAPBACK}][/a]

keep your ridiculous ideas on conducting listening tests to your own thread.


later

  • echo
  • [*][*][*]
64 kbps listening test 2005
Reply #156
Quote
Quote
Regarding samples, I have enough now, thank you. It's a bit hard to decide which ones to use, since almost all of them are more or less killer samples.
[{POST_SNAPBACK}][/a]


Beware of the bias of testing only killer samples. Comparing codecs on killer samples will only give you a hint on how they perform... on killer samples. Not on regular music. See [a href="http://www.hydrogenaudio.org/forums/index.php?showtopic=36184]here[/url] for a thread on the subject.
[a href="index.php?act=findpost&pid=319563"][{POST_SNAPBACK}][/a]

Heh, now this has become a fact? 

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I think it'd be better to conduce an 128 kbps test once LAME 3.97 and Nero AAC are out.

I think that would be more interesting for everyone...

64 kbps listening test 2005
Reply #157
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I think that would be more interesting for everyone...
[a href="index.php?act=findpost&pid=319720"][{POST_SNAPBACK}][/a]


I bet the two encoders will be released right after my summer vaction is over.  Hope not.

  • rjamorim
  • [*][*][*][*][*]
64 kbps listening test 2005
Reply #158
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I bet the two encoders will be released right after my summer vaction is over.  Hope not.[a href="index.php?act=findpost&pid=319726"][{POST_SNAPBACK}][/a]


You might have LAME 3.97 beta before your vacation is over, but you'll hardly have final!
Get up-to-date binaries of Lame, AAC, Vorbis and much more at RareWares:
http://www.rarewares.org

64 kbps listening test 2005
Reply #159
Would you test with a beta or a final?

  • rjamorim
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64 kbps listening test 2005
Reply #160
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Would you test with a beta or a final?[a href="index.php?act=findpost&pid=319738"][{POST_SNAPBACK}][/a]


Wise words from Roberto:

Ask the Developers opinion. That way, you save your face and don't get cornered in case everything blows up.
Get up-to-date binaries of Lame, AAC, Vorbis and much more at RareWares:
http://www.rarewares.org

64 kbps listening test 2005
Reply #161
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Settings tweaking IST EVUL.


arghhhhhh .... 
then 2 pass streaming mode with default setting : it's an usual mode in WMEnc
cscript.exe wmcmd.vbs -a_codec WMA9STD -a_mode 4 -a_setting 64_44_2 -input C:\Audio -output C:\Audio

default are:
- 1.5*bitrate for maxbitrate
- 3 sec for maxbuffer

Quote
There you go. WMA Pro is not meant to be encoded at 64kbps.


In fact q10 quality is perhabs this mode ... but it's just impossible for you to obtain the good target bitrate for your specific samples tests ...
  • Last Edit: 12 August, 2005, 07:53:04 PM by Sagittaire

  • guruboolez
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64 kbps listening test 2005
Reply #162
Quote
Quote
Beware of the bias of testing only killer samples. Comparing codecs on killer samples will only give you a hint on how they perform... on killer samples. Not on regular music. See here for a thread on the subject.
[{POST_SNAPBACK}][/a]

keep your ridiculous ideas on conducting listening tests to your own thread.
[a href="index.php?act=findpost&pid=319701"][{POST_SNAPBACK}][/a]

Pieroxy's ideas have nothing ridiculous. He was very clear: a listening test involving VBR and CBR encoders should include low-bitrate encodings, mid-bitrate encodings and high-bitrate encodings.
I'm [a href="http://www.hydrogenaudio.org/forums/index.php?showtopic=36184&view=findpost&p=319058]quoting[/url] Pieroxy:
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So in an ideal test, you would have 160kbps, 130kbps and 90kbps samples. THAT would be representative, not merely 128kbps.


Now I'm quoting someone who's not used to post "ridiculous ideas" about listening tests, ff123:
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Ideally, you'd like the bitrate distribution to look somewhat like a bell curve with its mean at 128 kbit/s.

=> Exactly the same "ridiculous" idea about the "ideal" test.

And ff123 followed:
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For the 48 kbit/s test, if there are VBR codecs, I think we should strive to have about an equal number of bitrates above and below the average bitrate (which should work out to be 48 kbit/s on average across the sample set).

Would you also say that ff123 has ridiculous ideas about listening test organisation? I'd really like to see that...



I posted the bitrate distribution curve of VBR encoders involved in my latest 80 kbps listening test:
http://foobar2000.net/divers/tests/2005.07...UTION_WMA80.png
http://foobar2000.net/divers/tests/2005.07...ION_aoTuV80.png

For both encoders, ~50% of the total samples were encoded with a bitrate lower to the targeted bitrate, and the ~50 remaining percent were encoded with a bitrate superior to the targeted bitrate. The distribution is close to the perfect curve for WMA and classical music (150 samples), with both mean and median at exactly 80 kbps. The curve is perfectible for aoTuV (median is 75 kbps), but distribution is also near-symetrical from both side of the median value.
It was maybe luck - I don't know - or maybe a consequence of the huge number of samples involved in my test (150+35) which maybe help to get a good distribution.
  • Last Edit: 19 August, 2005, 12:27:47 AM by guruboolez