Here is a sample I found, extract of a well-known Van Halen title : Jump. The first seconds are really hard to encode, and I expect mpc to feel at ease with such sample. But the surprise is really big : --standard fail (easy ABX), --extreme fail (easy ABX), --insane too, and the --quality 10 test (express test) gave me a 16/20 score ! In comparison, vorbis 1.0 is more difficult for me to abx at -q 6 (but the bitrate is near 400 kbps).
http://membres.lycos.fr/guruboolez/ (http://membres.lycos.fr/guruboolez/)
Can someone confirm my impressions (headphone needed I suppose) ?
MPC --standard sounds OK to me - didn't try ABX or anything. Maybe a slightly longer sample would help?
MPC --standard sounds OK to me - didn't try ABX or anything. Maybe a slightly longer sample would help?
I'm not sure that a longer sample can help you. I've just upload a longer file.
Note that the first try I did was not concluant. I abruptly heard a small but significant difference (noiser sound, brighter too : can not really explain, and my percepcton are distorded by illness). This difference is not removed by higher bitrate.
no more test ?! Thanks to Chun-Yu.
I tried again. The first two minutes, I wasn't able to hear any difference with any file. Then, ABX tests were concluant again :
ABC/HR Version 0.9b, 30 August 2002
Testname:
1L = C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc6(114).wav
2L = C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc6 (179).wav
3L = C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc5(114).wav
4R = C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc7(114).wav
5L = C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc10.wav
6R = C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc8(114).wav
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General Comments:
première tentative sur le sample 2 (le 1 étant trop dur)
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1L File: C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc6(114).wav
1L Rating: 3.7
1L Comment:
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2L File: C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc6 (179).wav
2L Rating: 2.5
2L Comment:
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3L File: C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc5(114).wav
3L Rating: 3.0
3L Comment:
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4R File: C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc7(114).wav
4R Rating: 3.3
4R Comment:
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5L File: C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc10.wav
5L Rating: 4.6
5L Comment:
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6R File: C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc8(114).wav
6R Rating: 4.2
6R Comment:
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ABX Results:
Original vs C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc6(114).wav
13 out of 16, pval = 0.011
Original vs C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc6 (179).wav
10 out of 12, pval = 0.019
Original vs C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc5(114).wav
12 out of 12, pval < 0.001
Original vs C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc7(114).wav
11 out of 12, pval = 0.003
Original vs C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc10.wav
11 out of 16, pval = 0.105
Original vs C:\Ma musique\jump\20. Jump [HDCD Remaster] (2).mpc8(114).wav
12 out of 12, pval < 0.001
The test I performed was blitz-test, really fast.
The codec was the mppenc 1.14, and one with the old 1.79c at --xtreme profile. I decoded all files with the 1.93 mppdec version. Note that the worst file I founded was suprinsingly the --extreme profile from Andree Buschmann. It's hard for me to to organize into a hierarchy the 6 files. Difference are subtile between mpc files. But I'm sure that there is a real progress between mpc --standard, and mpc --quality 10, and that the extreme profile from the old codec is not as good in this sample than the 1.14 one.
Yes, I hear it
first winabx round (listening and guessing...) mpc --standard --xlevel (mppenc 1.14b)
21:07:54 1/1 p=50.0%
21:09:00 1/2 p=75.0%
21:09:32 2/3 p=50.0%
21:10:24 3/4 p=31.2%
21:10:41 4/5 p=18.8%
21:10:56 5/6 p=10.9%
21:11:55 6/7 p= 6.2%
21:12:17 7/8 p= 3.5%
21:13:11 8/9 p= 2.0%
21:13:16 test finished
Btw, Guruboolez, I've read here somewhere that you hear a difference with (quote) "2000 year old string instruments" encoded with mpc.
I suspect the same problem with "only 400 year old" baroque strings, but I haven't found a clear abx-able sample yet, do you have one?
-tm
Btw, Guruboolez, I've read here somewhere that you hear a difference with (quote) "2000 year old string instruments" encoded with mpc.
I suspect the same problem with "only 400 year old" baroque strings, but I haven't found a clear abx-able sample yet, do you have one?
No. The erhu (2000 year old) sample concern LAME --alt-preset only, and not mpc. I recently found the same problem with a 300 year old flute The only « problem » with mpc with these instrument is the average bitrate, not the quality. Yesterday, I encode a whole harpsichord disc with mpc standard : 1.14 gave me a 220 average bitrate, and 1.15alpha reached 235 kbps ! For low bitrate encoding (under 100 kbps) with these recordings, mpc is one of the worst codec I heard.
But I never heard an artifact or a difference between original with a 'classical' encoding with musepack (> standard). I searched, but never found. I'm sometime able to hear subtile difference with --standard, but score are really fragile, and I can't conclude anything from it.
And thanks for the test, and for the results
mppdec gets some 'overdrives' (whatever that is? something to do with the fact the file is kinda 'hard limited'?), i used --xlevel in cli as well:
mppdec Jump_long.mpc
MPC Decoder SV7 1.1 3DNow/SSE (C) 1999-2002 Buschmann/Klemm/Piecha/Wolf
decoding of file 'Jump long.mpc'
to device /dev/audio (Windows WAVEOUT Audio)
195.0 kbps, 0:07.49, SV 7.0, Profile 'Standard' (Release 1.1)
0:07.47 (runtime: 6.48 s speed: 1.15x)
18 Overdrives, maximum level 34208, rerun with --scale 0.95784
edit: cant abx with ver 1.1 profile standard
edit2: ok, sounds like at the beginning the right channel wont hit in at the right time, but still cant abx that.
mppdec gets some 'overdrives' (whatever that is? something to do with the fact the file is kinda 'hard limited'?), i used --xlevel in cli as well:
mppdec Jump_long.mpc
MPC Decoder SV7 1.1 3DNow/SSE (C) 1999-2002 Buschmann/Klemm/Piecha/Wolf
decoding of file 'Jump long.mpc'
to device /dev/audio (Windows WAVEOUT Audio)
195.0 kbps, 0:07.49, SV 7.0, Profile 'Standard' (Release 1.1)
0:07.47 (runtime: 6.48 s speed: 1.15x)
18 Overdrives, maximum level 34208, rerun with --scale 0.95784
I doesn't have this problem. Tried mppdec -> file & -> device, and no errors.
I haven't perform again a test with --xlevel switch : EAC comparison tool indicate a total identity between mpc --standard and --standard --xlevel.
Thnx for reply
MPC --standard sounds OK to me - didn't try ABX or anything. Maybe a slightly longer sample would help?
I'm not sure that a longer sample can help you. I've just upload a longer file.
Note that the first try I did was not concluant. I abruptly heard a small but significant difference (noiser sound, brighter too : can not really explain, and my percepcton are distorded by illness). This difference is not removed by higher bitrate.
Tested MPC v1.14 --standard, abx 16/24 and 11/16, combined is 27/40 (p-val < 0.02). Hard to ABX, with a vacuum cleaner going in the background!
The MPC version adds a lower "growl" to the sound not present in the original... or maybe it removes the growl, I don't know. It's hard to describe...
I wonder if adding some sound to the beginning of the file will improve quality, like it sometimes does with Lame? Will test by copying clip several times over and ABXing a portion from the middle...
Have you try anything higher than --standard ?
A small and rare difference with --standard doesn't bother me, but a audible difference at --extreme and above is more annoying
Have you try anything higher than --standard ?
A small and rare difference with --standard doesn't bother me, but a audible difference at --extreme and above is more annoying
Standard is right on the limit of my perception. The sample clip's noise is similar to the frequency of my screeching processor fans, which makes it hard to hear.
I keep getting somewhat-significant results with Jump.wav (11/16), and I think I can hear a difference. But I can't clearly hear a difference when I listen to the "looped" sample. To make the looped sample, I copied Jump.wav five times in a row to make a 2.6 second clip, encoded the whole clip, decoded it, and then extracted the third loop of Jump.wav (approximately 1.05 seconds to 1.55 seconds) for testing.
guruboolez, I will try a higher setting on Jump.wav, but I may not be able to provide conclusive results until tomorrow (12 hours for me). Perhaps you can test a "looped" sample to hear if it makes a difference?
I'm tired too, but confident.
I looped the original file, encoded it at --quality 10 (I'm very confident !), opened the waveform in cooledit, cut the third part, and saved it in .wav.
Then I opened ABC/HR, loaded the original, the looped too, and the previous --quality 10 (based on simple Jump.wav) at the same time.
I wasn't able to hear anything B)
I tried again, but at --quality 7 (--insane with mppenc 1.14).
ABX score are now interesting :
40/60 and 27/30 for the second mysterious file. Is one better than the other ? Why xx/60 ?
The details are instructive :
0 of 1, p = 1.000
1 of 2, p = 0.750
1 of 3, p = 0.875
2 of 4, p = 0.688
3 of 5, p = 0.500
4 of 6, p = 0.344
4 of 7, p = 0.500
5 of 8, p = 0.363
5 of 9, p = 0.500
6 of 10, p = 0.377
6 of 11, p = 0.500
7 of 12, p = 0.387
8 of 13, p = 0.291
9 of 14, p = 0.212
9 of 15, p = 0.304
9 of 16, p = 0.402
9 of 17, p = 0.500
9 of 18, p = 0.593
10 of 19, p = 0.500
11 of 20, p = 0.412
11 of 21, p = 0.500
11 of 22, p = 0.584
12 of 23, p = 0.500
13 of 24, p = 0.419
13 of 25, p = 0.500
14 of 26, p = 0.423
15 of 27, p = 0.351
16 of 28, p = 0.286
17 of 29, p = 0.229
18 of 30, p = 0.181
19 of 31, p = 0.141
19 of 32, p = 0.189
20 of 33, p = 0.148
21 of 34, p = 0.115
21 of 35, p = 0.155
22 of 36, p = 0.121
22 of 37, p = 0.162
23 of 38, p = 0.128
23 of 39, p = 0.168
23 of 40, p = 0.215
23 of 41, p = 0.266
24 of 42, p = 0.220
25 of 43, p = 0.180
26 of 44, p = 0.146
27 of 45, p = 0.116
28 of 46, p = 0.092
29 of 47, p = 0.072
30 of 48, p = 0.056
31 of 49, p = 0.043
32 of 50, p = 0.032
33 of 51, p = 0.024
34 of 52, p = 0.018
35 of 53, p = 0.013
35 of 54, p = 0.020
36 of 55, p = 0.015
37 of 56, p = 0.011
37 of 57, p = 0.017
38 of 58, p = 0.012
39 of 59, p = 0.009
40 of 60, p = 0.007
The first twenty are non-significative : 11/20. Then, the following ABX score are slightly better : 12/20 [on 21-40] and 20 last ABX are really good : 17/20.
I need a warm-up, like an athlete
In these conditions, it's difficult to conclude that SAMPLE 1 (40/60) is better than SAMPLE 2 (27/30).
Sample 1 is the looped file, and the 'easiest' and second sample is the simple_jump file.Nevertheless, I had a strong feeling that sample_2 different (and more degraded) was from sample_1. I tried to ABX 1 against 2 : 17/20. Details :
0 of 1, p = 1.000
1 of 2, p = 0.750
1 of 3, p = 0.875
2 of 4, p = 0.688
2 of 5, p = 0.813
3 of 6, p = 0.656
4 of 7, p = 0.500
5 of 8, p = 0.363
6 of 9, p = 0.254
7 of 10, p = 0.172
8 of 11, p = 0.113
9 of 12, p = 0.073
10 of 13, p = 0.046
11 of 14, p = 0.029
12 of 15, p = 0.018
13 of 16, p = 0.011
14 of 17, p = 0.006
15 of 18, p = 0.004
16 of 19, p = 0.002
17 of 20, p = 0.001
...A perfect 15/15 on the end of the test.
You were right : same audio informations can be encode differently !
kinda hard to belive only my mppdec is 'biased', has any1 else got to the same 'overdriven' situation? (cos if that is the case you been abxing decoder clipping imho)
edit: i got same overdrives with mppenc 1.14 beta and mppdec 1.93j
edit2: @Tim Mervielde&SometimesWarrior: you forgot to mention how the file was decoded?
edit3: if i ignore the decoder warning, file is actualy clipping (tested in sound forge, clipping just after 6s)
kinda hard to belive only my mppdec is 'biased', has any1 else got to the same 'overdriven' situation? (cos if that is the case you been abxing decoder clipping imho)
.../... (tested in sound forge, clipping just after 6s)
The artifact appeared at the first second, not at the sixth
kinda hard to belive only my mppdec is 'biased', has any1 else got to the same 'overdriven' situation? (cos if that is the case you been abxing decoder clipping imho)
.../... (tested in sound forge, clipping just after 6s)
The artifact appeared at the first second, not at the sixth
i guess soundforge & its peakmeter arent really reliable then
MPC Decoder SV7 1.93j 3DNow/SSE (C) 1999-2002 Buschmann/Klemm/Piecha/Wolf
decoding of file 'Jump long.mpc'
to device /dev/audio (Windows WAVEOUT Audio)
193.0 kbps, 0:07.49, SV 7.0, Profile 'Standard' (Beta 1.14)
0:07.47 (runtime: 6.48 s speed: 1.15x)
15 Overdrives, maximum level 33735, rerun with --scale 0.97127
edit: eac wav editor as second opinion, this clipping appears at just around 1st s: