Is there a way to control desktop colours?

[Tourist Trap]

Hi,

In Djvu viewer I've an option to change white background to black and black text to white. Not in adobe reader, not in any other softwares I have.

So I was wondering if one could get this kind of control level from the API?

It may seem unlikely but they have done a lot about what they call accessibility (for disabled persons), so maybe it's the kind of feature sitting somewhere in a corner.

Any idea?

[St_W]

Google (or any other search engine) is your friend:
https://forums.adobe.com/thread/395433

[Tourist Trap]

Google (or any other search engine) is your friend:
https://forums.adobe.com/thread/395433

Thanks , this is a first step. Even if for what reason, adobe made this very unpracticable to switch in real time (one click) between reverse and normal.

Anyway, the main question remains. I'm now thinking about making a kind of screen saver that would replace the desktop colour scheme. The main advantage for this is energy consumption saving without killing the screen. Possible or not. I'll of course try to search about this on the web, but making screen savers in fb is just so easy.

[grindstone]

The main advantage for this is energy consumption saving without killing the screen.

That's only the case if you're still unsing an old CRT-monitor. The power consumption of a modern TFT-monitor doesn't depend on the brightness of the screen.

[Tourist Trap]

The main advantage for this is energy consumption saving without killing the screen.

That's only the case if you're still unsing an old CRT-monitor. The power consumption of a modern TFT-monitor doesn't depend on the brightness of the screen.

Even a bright white page is consuming equal amout of energy than a grey dark equivalent scene?

I wasn't aware of that change. The fact is I had a modern tv that was flat, and certainly not crt, even if I dont know if it was led or lcd or so on. This tv had a setting in the menu to lower the energy consumption. It seems that it was fading the colours.

[caseih]

I think what you meant to say was that the color and intensity of the pixels displayed has no bearing on the power consumption. Strictly speaking, brightness, though, is a function of the backlight, which will consume power depending on the level of brightness. That's why laptops dim the screen when on battery life, and darken it when the computer is inactive.

To Tourist Trap, yes he's correct. Displaying a full screen of grey is the same energy as displaying a full screen of white. Your TV's setting probably just lowered the backlight level.

EDIT: Just wanted to add that he said specifically applies to the TFT LCD displays common today. Many cell phones use OLED display, and now some larger monitors are starting to use the technology because of the ability to create vibrant colors. OLED displays emit light on a per-pixel basis, unlike LCD which just passes light through. Thus a dark screen on OLED does use less battery than a bright screen. This is one reason by Android in the past used to use a lot of dark themes. Many Android phones use OLED and thus the darker themes had better battery life. The iPhone was always LCD, so Apple has traditionally used very light backgrounds (white) for their UI because there was no additional cost to do so. I've heard the upcoming iPhone may offer an OLED screen, so it will be interesting to see if Apple adjusts their UI colors to enhance battery life.

[Zippy]

Plasma TVs, which are flat-screen, are subject to burn-in and their power consumption varies with picture brightness. I should say "were" flat-screens, as they are no longer sold.

The now-ubiquitous LED/LCD screens do not vary consumption by picture brightness, technically, but the always-on backlights can use more electricity if turned "up" to compensate for bright ambient light.

If it is not a plasma or CRT type then a screen saver will neither save the screen from burn in or save electricity.

See caseih's post for OLED screens, this outside my experience.
.

[Tourist Trap]

Ok that makes sense. This tv had an option to compensate ambiant luminosity, so in sunny ambiance maybe it was where the consumption was increased due to backlight.

My second concern, left aside the problem of energy consumption (even if my netbook seems to save energy by reducing brightness or similar, as well as the samsung tablet), is about the fact that the reading comfort tends to get fastly exhausted if the colour scheme is bright. At least switching sometimes the colours gives some rest to the eyes.

Aside again, but about the eyes exhaustion, I'm running personally this little experiment those days.
1/I'm reading some docs on tablet with scrolling the screen -> reduced amount of eyes moves. I get the eyes blurred very fastly and have to pause reading.
2/I use the page per page scrolling, and read from up to down like with a real book -> I feel much better from the eyes point of view. Of course this is reducing the overall comfort if I'm trying to run over a big document very fast. But the gain for the eyes is really effective.

So I even wonder why there is still no application to help people get reminded to keep a minimal amount of eyes exercice. This would be easy to implement with the forward camera, that is watching you. And even without this, I can think of many other ways.

Ok this was just to say that not much is done today for ergonomy/accessibility (and energy saving strategies engraved os api side without necessarily hardware in mind - which would be really nice). Not enough anyway.

[caseih]

On my Linux PC I run a program called "redshift" that gradually reddens the display as dusk comes on. I find this reduces my eye strain. I also have a similar app on my phone and tablet, called Twilight. I find reducing the harsher blueish color of the screen at night (particularly when the lights in my house are all about 2700k) makes my eyes feel better. Whether it reduces problems with sleep patterns I can't say, though, which is what some people claim. A popular Windows utility to do this is called f.lux[1]

When it comes to reading on a device, I love my Kindle. The reflective display is gentler on the eyes (less flicker too). I dream of a day when we'll have displays that are full color, high resolution, and capable of fast frame video that are 100% reflective, like a magazine page. In the meantime I really wish dual-mode technology would get better and become more available. I wish my phone had a high-res reflective mode on it for use in bright sunlight. I had high hopes for the Pixel Qi screen, but apparently it never quite turned out to be as good as hoped. For those that don't know the Pixel Qi had two modes. One was more like a normal TFT LCD display with a blacklight for use in doors, and the other was a 100% reflective mode where ambient light was used only, though the screen was black and white only but could be used in full sunlight.

[1] https://justgetflux.com/

[Tourist Trap]

[1] https://justgetflux.com/

It seems that kindle like screens are definitely nice for the eyes. Even in pc, I've always prefered the non-bright screens in any case. It's really more comfortable on the long run.

I've checked about flux stuff. Not a bad concept. Even quite smart. Just wondering why it doesnt rely on the cameras for sampling ambiance in real time?

Whatever, about eyes movements, that are so essential to prevent the eyes to get exhausted (even broken after a while), this is a demo below where I show what I would expect from a careful manufacturer.

This demonstrate a visual alarm when you are likely being reading text document. It triggers a red light (supposedly hardware diod), that one should look at each 5 seconds. The alarm is stopped at button press, but in reality it should stop and come back a little more randomly.

Code: Select all

 'draws a tablet

#macro _Data(relativeCounter, absoluteCounter)
	data 
#endMacro

type CHRONOMETER extends OBJECT
	declare static function ResetTime() as double
	declare static function ReturnEllapsedTime() as double
	declare static sub DrawChronometer(byval x as integer, byval y as integer)
	private:
	static as double	initialTime
end type
dim as double	CHRONOMETER.initialTime
function CHRONOMETER.ResetTime() as double
	CHRONOMETER.initialTime => TIMER
	'---->
	return CHRONOMETER.initialTime
end function
function CHRONOMETER.ReturnEllapsedTime() as double
	'---->
	return (TIMER - CHRONOMETER.initialTime)
end function
sub DrawChronometer(byval x as integer, byval y as integer)
	dim as double	t => CHRONOMETER.ReturnEllapsedTime()
	'
	line (x, y)-step(8*len(str(t)), 12), rgb(240,250,245), bf
	draw string(x,y + 2), str(t), 0
end sub

sub TabletReadAndDraw()
	dim as integer	counter
	dim as integer	x, y
	
	'border
	restore BORDER
	for counter = 1 to 9
		read x, y
		if counter=1 then
			pReset(x, y)
		else
			line step-(x, y)
		end if
	next counter
	'screenborder
	restore SCREENBORDER
	for counter = 1 to 5
		read x, y
		if counter=1 then
			pReset(x, y)
		else
			line step-(x, y)
		end if
	next counter
	restore BUTTON
	for counter = 1 to 5
		read x, y
		if counter=1 then
			pReset(x, y)
		else
			line step-(x, y)
		end if
	next counter
	'
end sub

sub DrawDocument()
	line (114,44)-step(170,270), rgb(200,150,250), bf
	line (120,50)-step(160,260), rgb(240,250,250), bf
	for i as integer = 1 to 30
		draw string (124 - 5*rnd(),58 + i*8), "hello document text", rgb(20,20,40)
	next i
end sub

sub EyeAttentionCatcherTrigger()
	static as double	initialTime
	static as integer	n
	'
	if (TIMER - initialTime)<2 then
		n += 1
		if n>=0 then 
			circle (112,340), 8, rgb(250,n,120), , , , f
		else
			circle (112,340), 9, 0, , , , f
		end if
	else
		initialTime = TIMER
		n = -50
	end if
end sub

function TestButton() as boolean
	dim as integer	gmX, gmY, gmBtn
	getMouse gmX, gmY, , gmBtn
	'
	if gmX>=171		andAlso _ 
	   gmX<=234		andAlso _ 
	   gmY>=345		andAlso _ 
	   gmY<=357		then
		if gmBtn>0 then
			'---->
			return TRUE
		else
			'---->
			return FALSE
		end if
	else
		'---->
		return FALSE
	end if
end function

'______________________________________________________INIT
screenRes 400, 400, 32
CHRONOMETER.ResetTime()

'______________________________________________________MAIN
TabletReadAndDraw()
#macro _Repaint()
	paint (1,1), rgb(100,20,20), rgb(255,255,255)
	paint (104,33), rgb(255,255,255), rgb(255,255,255)
	paint (107,37), rgb(40,80,120), rgb(255,255,255)
	paint (172,347), rgb(200,200,200), rgb(255,255,255)
#endMacro
_Repaint()
circle (112,340), 12, rgb(200,220,120), , , , f
circle (112,340), 9, 0, , , , f
DrawDocument()

do
	screenLock
		DrawChronometer(10,10)
		if CHRONOMETER.ReturnEllapsedTime()>5 then
			EyeAttentionCatcherTrigger()
		else
			circle (112,340), 9, 0, , , , f
		end if
	screenUnlock
	'
	if TestButton() then
		screenLock
			_Repaint()
			DrawDocument()
			CHRONOMETER.ResetTime()
		screenUnlock
	end if
	'
	sleep 15
loop until inkey()=chr(27)


getKey()


'______________________________________________DATA SECTION
'border
BORDER:
_Data(001, 001)		103, 32
_Data(002, 002)		290, 32
_Data(003, 003)		297, 39
_Data(004, 004)		297, 356
_Data(005, 005)		290, 362
_Data(006, 006)		103, 362
_Data(007, 007)		98, 356
_Data(008, 008)		98, 39
_Data(009, 001)		103, 32

'screenborder
SCREENBORDER:
_Data(010, 001)		106, 36
_Data(011, 002)		287, 36
_Data(012, 003)		287, 324
_Data(013, 004)		106, 324
_Data(014, 005)		106, 36

'button
BUTTON:
_Data(015, 001)		171, 345
_Data(016, 002)		234, 345
_Data(017, 003)		234, 357
_Data(018, 004)		171, 357
_Data(019, 005)		171, 345

'(eof)

[caseih]

I've checked about flux stuff. Not a bad concept. Even quite smart. Just wondering why it doesnt rely on the cameras for sampling ambiance in real time?

I suppose the reason is that the theory behind flux is that the screen color is as much about your circadian rhythm as anything else. When it's the middle of the day, the harsher blue color is okay as that's what your eyes and brain are used to anyway (sunlight is pretty white and intense actually), even while you're indoors. It's as night starts to come on that your brain begins to expect the hues to redden. The theory is that the blueish light when it's not actually daytime can disrupt your sleep cycle. There's not a lot of evidence to support this theory that I know of, though. For me my computer is right next to a big window, so the synchronizing to the clock works perfectly.

[Tourist Trap]

I suppose the reason is that the theory behind flux is that the screen color is as much about your circadian rhythm as anything else. When it's the middle of the day, the harsher blue color is okay as that's what your eyes and brain are used to anyway (sunlight is pretty white and intense actually), even while you're indoors.

Ok! It's true that on computers I use, I always add more red value, for green or blue in excess tends to irritate me.

But I've also noticed that sometimes an excess of blue was just Ok. So I guess now that it should have occured in the mornings!