AMTuring
25th November 2005, 03:04
I have not been active on the forum lately because of moving from one country to another, house hunting, work, etc.
I thought folks might be interested in the correlation comparison of the new LAME 3.97 beta. Here is a chart comparing 3.96.1 and 3.97 beta. I have seen some discussion over on HA about using --vbr-new instead of --vbr-old. So I included a comparison with --vbr-old.
http://putfile.com/pic.php?pic=11/32719533944.gif&s=x12
The points correspond to -V 0-6 and 8. -V 7 produces poor correlations on all versions. The spacing of average bitrates is much improved on 3.97 and the correlation values are very good.
As in my earlier post there were 35 x 30 second audioclips used in the comparison. This chart shows the average of all 35 clips.
However, the difference with 3.96.1 or even the retired 3.90.3 are still small. I would not worry about mp3 encoded with the old versions.
P.S. I found the problem with -V7. I forgot that it resamples to 33 kHz from the usual 44.1 kHz. I corrected the test and can now include this setting in the tests. I cleaned up the plot and zoomed in on two additional views to make the plots easier to read.
Updated plot:
http://putfile.com/pic.php?pic=11/32822570951.gif&s=x12
Zoom of 3.96.1 (current) vs 3.97 (beta):
http://putfile.com/pic.php?pic=11/32822574884.gif&s=x12
Zoom of 3.97 (beta) vbr old vs. new:
http://putfile.com/pic.php?pic=11/32822581915.gif&s=x12
I thought folks might be interested in the correlation comparison of the new LAME 3.97 beta. Here is a chart comparing 3.96.1 and 3.97 beta. I have seen some discussion over on HA about using --vbr-new instead of --vbr-old. So I included a comparison with --vbr-old.
http://putfile.com/pic.php?pic=11/32719533944.gif&s=x12
The points correspond to -V 0-6 and 8. -V 7 produces poor correlations on all versions. The spacing of average bitrates is much improved on 3.97 and the correlation values are very good.
As in my earlier post there were 35 x 30 second audioclips used in the comparison. This chart shows the average of all 35 clips.
However, the difference with 3.96.1 or even the retired 3.90.3 are still small. I would not worry about mp3 encoded with the old versions.
P.S. I found the problem with -V7. I forgot that it resamples to 33 kHz from the usual 44.1 kHz. I corrected the test and can now include this setting in the tests. I cleaned up the plot and zoomed in on two additional views to make the plots easier to read.
Updated plot:
http://putfile.com/pic.php?pic=11/32822570951.gif&s=x12
Zoom of 3.96.1 (current) vs 3.97 (beta):
http://putfile.com/pic.php?pic=11/32822574884.gif&s=x12
Zoom of 3.97 (beta) vbr old vs. new:
http://putfile.com/pic.php?pic=11/32822581915.gif&s=x12