Samsung Galaxy S6 Phone System Update Today

My Samsung Galaxy S6 smartphone was running Android 6.0.1 until today, when the notification reached me, that a System Update was available.

So once I got home, I eagerly installed that, and my phone is now running Android 7.0 – which is also known as Nougat.

I am impressed with this, even though the main feature I see is the screen layout. Obviously, there is more to Android Nougat than that. But, while it seems at first glance that everything worked as planned, I cannot honestly claim that everything is in fact 100%, because I haven’t had the time to test many of the new features yet.

For the moment, I’d say that the update was a success.

There was one detail which I specifically did check. One of the usage habits with which I’ve used Marshmallow and Nougat in the past, was to white-list some of my apps, from Battery Optimization. The reason I need to do this, is my desire to allow some of these apps to run in the background, even though I may not be making any foreground use of them. And, these apps are often older, in that their devs have not adapted them to the newer ways of allowing this to happen. Since modern Android aggressively kills apps that fit this description, my devices have white-lists of apps that should not be killed.

What I did expect is that the update to 7.0 would roll back all my personal white-lists. But I still want them. If the app is too outdated to run on 6.0.1 correctly, then it will probably also be too outdated to run on 7.0 correctly.

It took me a few tries, to find where I can do this.

One of the things which Samsung has done with this update, is to design a UI which is user-friendlier, and also more different from Stock Android, than earlier Samsung versions were. And this means that if I want to find something advanced, I need to poke around in the new settings menu a bit.

I have restored my own preference, that my phone is to have a more extensive white-list, for Battery Optimization, than I feel the Tablet should have. And this relates to the fact that while I do want my phone to send me my many notifications, there is little use if the same notifications are always sounding on the tablet. Chances are, I’ll have my phone in my shirt-pocket, while I’m sitting in front of my tablet. And then, if I want my tablet-view of something that the phone just notified me about, manually activating the corresponding app on the tablet works just fine.

I think that any data-miners might get confused by my habits, of inviting many notifications on my phone, but often not tapping on them, to open the corresponding app-pages. But the way I’m set up, the notification text itself usually gives me enough information, that I can just swipe the notification away, and still have a general sense of what’s going on in the world.

Dirk

(Edit 05/20/2017 : )

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Thoughts About Software Equalizers

If a software-equalizer possesses GUI controls that correspond to approximate octaves, or repeated 1-2-5 sequences, it is entirely likely to be implemented as a set of bandpass filters acting in parallel. However, the simplistic bandpass filters I was contemplating, would also have required that the signal be multiplied by a factor of 4, to achieve unit gain where their low-pass and high-pass cutoff frequencies join, as I described in this posting.

(Edit 03/23/2017:

Actually, the parameters which define each digital filter, are non-trivial to compute, but nevertheless computable when the translation into the digital domain has been carried out correctly. And so a type of equalizer can be achieved, based on derived bandpass-filters, on the basis that each bandpass-filter has been tuned correctly.

If the filters cross over at their -6db point, then one octave lower or higher, one filter will reach its -3db point, while the other will reach its -12db point. So instead of -12db, this combination would yield -15db.

The fact that the signal which has wandered into one adjacent band is at -3db with respect to the center of that band, does not lead to a simple summation, because there is also a phase-shift between the frequency-components that wander across.

I suppose that the user should be aware, that in such a case, the gain of the adjacent bands has not dropped to zero, at the peak of the current band, so that perhaps the signal will simplify, if the corner-frequencies have been corrected. This way, a continuous curve will result from discrete settings.

Now, if the intention is to design a digital bandpass filter with greater than 6 db /Octave falloff curves, the simplistic approach would be just to put two of the previous stages in series – into a pipeline resulting in second-order filters.

Also, the only way then to preserve the accuracy of the input samples, is to convert them into floating-point format first, for use in processing, after which they can be exported to a practical audio-format again. )

(Edit 03/25/2017 :

The way simplistic high-pass filters work, they phase-shift the signal close to +90⁰ far down along the part of the frequency-response-curve, which represents their roll-off. And simplistic low-pass filters will phase-shift the signal close to -90⁰ under corresponding conditions.

OTOH, Either type of filter is supposed to phase-shift their signal ±45⁰, at their -3db point.

What this means is that if the output from several band-pass filters is taken in parallel – i.e. summed – then the center-frequency of one band will be along the roll-off part of the curve of each adjacent band, which combined with the -3db point from either its high-pass or its low-pass component. But then if the output of this one central band is set to zero, the output from the adjacent bands will be 90⁰ apart from each other. )

(Edit 03/29/2017 :

A further conclusion of this analysis would seem to be, that even to implement an equalizer with 1 slider /Octave properly, requires that each bandpass-filter be a second-order filter instead. That way, when the signals wander across to the center-frequency of the slider for the next octave, they will be at -6db relative to the output of that slider, and 180⁰ phase-shifted with respect to each other. Then, setting the center slider to its minimum position will cause the adjacent ones to form a working Notch Filter, and will thus allow any one band to be adjusted arbitrarily low.

And, halfway between the slider-center-frequencies, the gain of each will again be -3db, resulting in a phase-shift of ±90 with respect to the other one, and achieving flat frequency-response, when all sliders are in the same position.

The problem becomes, that if a 20-band equalizer is attempted, because the 1 /Octave example already required second-order bandpass-filters, the higher one will require 4th-order filters by same token, which would be a headache to program… )

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