Stereo Tool

Have had a "veg out" day...where I haven't really wanted to think about anything. Will do more tests tomorrow.

I've done some tests myself, and the CPU load difference on my system is actually bigger than what you are measuring.

Still measuring now, will add the remaining results here later.

Preset Bojcha's webradio:
1:24 - 6.10
1:12 - 6.20 BETA 125 WITHOUT 'rrr rrr rrr' filter
1:09 - 6.20 BETA 125 (22% slower than 6.10)
1:11 - 6.20 BETA 125 without AEHP
1:14 - 6.20 BETA 125 without AEHP and STRICT BASS clipping

So:
- rrr rrr rrr filter costs 3 seconds (4%)
- AEHP costs 2 seconds (3%)
- STRICT BASS CLIPPING costs 3 seconds (4%)

Without clipper:
2:05 - 6.10
1:53 - 6.20 BETA 125
11% slower.

FM output + oversampling:
1:16 6.10
1:04 6.20 BETA 125
19% slower.

[Odd. a bit later I'm doing the same measurement and now I'm getting 1:18 vs. 1:02 -> 25% increase.]


So the CPU load appears to be around 20% higher than that of version 6.10. Caused by 3 things: Multiband, pre-ringing protection and clipping.


Edit: Now I also measured the difference in Multiband without the pre-ringing protection filter. And it's about 5% heavier than in 6.10. That must be the voice protection and band 1+2 link. In total this difference is small (about 1%).

--> Odd. The 2nd measurement of BETA125 FM above was done with these changes, and the CPU load is suddenly 6% higher than before. Might indeed be a memory/caching issue.


I will do a quick attempt to improve the performance of the pre-ringing protection (that should be relatively easy), but don't expect too much from it (because it only uses about 6% of the total, max gain would be around 2-3%). And I'll look into strict bass clipping and AEHP. But I won't spend more than a few hours on this.

One quick question about MB.
First there is Compress/Limit then clippers. Question is: Does Compress/limit reads signal after clippers?

No? Clipping is just the final step.

OK, I thought maybe it would be better to read after clippers. especially on last bands. (Feed-Forward)
btw. How's going Composite clipper?

Not started yet, first going to finish 6.20. Which is almost finished now (what remains is trying to improve the performance a bit and adjusting/adding new presets).

ow .. i have one.. or two.

FLAC files are delivered to Stereo Tool by Winamp in bigger chunks. Since it is useless to update the screen inside a chunk (would be overwritten immediately), this means that the refresh rate gets lower.

OK. Thanks for looking into it.

The veg-out has turned to weary resignation on things (not just this, many things), and brake job, lawn work, and other obligations are going to come into play in a few hours, so I'm going to continue to be a slacker for a while...

Because FLAC and Vorbis have different block sizes than the default Nullsoft MPEG plugin.

Nullsoft MPEG plugin is 512 samples per frame, where FLAC and Vorbis are 576 per frame. Stereo Tool (if this is the case) is updating the GUI only when a new frame is calling the callback of the DSP plugin. I know you wouldn't have experienced it, but the Winamp Breakaway plugin works the same way for the GUI, instead of running in its own thread.

If it's that way, putting it into its own thread could definitely maybe help to smooth out Stereo Tool operation under Winamp under high CPU usage.

[edit]
ah, hans answered this, in less words, hehe
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