So, how to change the depth?
 

Nevertheless, xdpyinfo also says that 24 and 32 color depths are supported. Any way to experiment with this? If I write /etc/X11/Xorg.conf with Depth 24, will it work? Is there any program like xrandr which can change the color depth on-the-fly?

Re: Screen Colours
 

The thread "N900 color depth: 16million or 65K collors?" with six posts has been merged into this thread.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

I can say its 16 million, I don't see the colour lack like i do on a pc with 65k.

The spec says its 16mill so it is. End of.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

funny that, the German site listed as 65k! This is indeed confusing, official europe Nokia did list "up to 65K colour"and GSMARENA listed 16M colour. What to believe? are we all being lied by NOKIA or by ourselves?

65K colours:
http://europe.nokia.com/find-product...specifications

16M colours:
http://www.gsmarena.com/nokia_n900-2917.php

This can't be right. The N97 mini has 16.5mil colours and listed on Nokia official site.
http://europe.nokia.com/find-product...specifications

But N900 on the other hand has better colour and sharper, much better resolution and still only say 65K?

This is very misleading. Can anyone this this to Nokia and confirm the fact?

Re: Screen Colours / Color Depth: 16 million or 65K?
 

This can't be right! Even my N95-1 has a 16M colour. Nokia flagship can't be this low! Can it be possible that Nokia has fallen this cheap???

Re: Screen Colours / Color Depth: 16 million or 65K?
 

May I ask you, if you think N900 has "better colour and sharper, much better resolution" why should you care whether it's 65K or 16M? :)

Re: Screen Colours / Color Depth: 16 million or 65K?
 

this is the same reason why people buy snapdragon based mobiles, even if the experience is slower than on a different device.
it must be 1ghz or more, if not you're soooo from 1990..

Re: Screen Colours / Color Depth: 16 million or 65K?
 

A machine is only as good as it's slowest / weakest part...

By the same token its all about the sum of its parts too, and their interaction with each other that results in the final throughput.

Everyone comments on the clarity and resolution of my 900's screen. I don't care if its only 16bit colour depth. I'm happy and people envy the screen on my phone.

Nuff sed <big grin>

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Since people don't seem to be able to tell the difference anyway (it's really only possible with undithered gradients - but then you see clearly that it's 65k), why should marketing not simply write 16m in the specs as this sounds so much better? :)

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Because it would be unethical to market a feature you don't have? ;-)

Re: Screen Colours / Color Depth: 16 million or 65K?
 

The hardware supports 16 million
The OS supports 16 million

for performance, the OS is running the hardware at 65k colors.

It would be an interesting experiment to see how it performs running at a 32 bit depth, but not that interesting.

Note that even if X is running at 16 bit, it should(/might/I can't really remember anymore) be possible for an app to directly access/set the hardware framebuffer and display video/images at 32 bit depth.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

All LCDs used on mobile phones use TN-Film LCD matrices which gives them 6-bit per color (or in human-readable numbers - 64 levels of red, green and blue). However, since programming in 18bit is a bit awkward, again, while the displays can show 18bit (3 x 6bit per color), or 262144 different colors, framebuffers are limited to 16-bit (or 65536 different colors).

So N900, just like any other mobile device featuring a LCD screen, is capable only of 16-bit color palette (or less). And it doesn't stop only on cell-phones, most, if not all of the laptops also have 18-bit screens, but since they have greater resolution and stronger hardware they could do away with working on 24-bit palette and using various dithering methods to give an illusion of fuller color fidelity. M/PVA and H/S-IPS screens that could display real 24-bit color palette are way too expensive and way too power consuming for mobile devices.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

save for the iphad ... it uses ips, and is "mobile(ish)"

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Yes, but hardly a handheld, and certainly not a mobile phone... What's even more perplexing is that Apple uses TN-Film on their MacBooks (incl. Pro), while they've added an IPS screen on an arguably useless device, especially where such a screen is not needed at all...

Re: Screen Colours / Color Depth: 16 million or 65K?
 

The clarity of the screen doesn't help on the colours fluctuating when watching movies or display high quality images on it. If we have 16Mil colours then we can display higher definition images and displaying its colour vividly and exactly like how it supposed to be.

165xxxxxxcolurs > 65356colours

The more colours the better display, and no need dithering just to fool the eyes to believe that the colour is there.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

It seems like everyone thought the N900 has 16M colour TFT resistive screen, but it actually got only a fraction of the 16M colours. 65k is just out dated. After find out about this, my N900 seem to be an old lady with so much cosmetic makeup on to flush the flaw.. of the imperfection.


I've found mixed of blog said that the N900 has 16M colours and some say 65k colours.

http://www.conceptsnews.com/htc-hd2-vs-nokia-n900/
"The display is great at both phones.The resolution is the same 800X480 but the HD2 has a screen of 4.3” wider than the N900 that only has 3.5”.But that’s not a big loose for the N900 because it has 16M colors when the HD2 only has 65k.But not so bad after all."


http://www.phonegiz.com/2010/02/nokia-n900-review.html
"The fully functional keyboard QWERTY is not the only easy feature for you to gain comfortable usage of the phone but also the touchscreen. The N900 has a 3.5 inch capacitive touch screen TFT 16 million colors and offers resolution 800 x 480 pixels. The series features screen acceleration sensor for the automatic sensor and proximity to disable the auto-off included."


http://www.articleultimate.co.cc/?p=1028
"Whereas Nokia N900’s 3.5 inches TFT Touch Screen has 480 x 800 Pixels resolution and offers 16 Million colours. "


http://en.wikipedia.org/wiki/Nokia_N900
"The Nokia N900 has a 3.5 inch resistive touchscreen with a resolution of 800 × 480 pixel (WVGA, 267 ppi) capable of displaying up to 16.7 million colors.[30] The LCD is transreflective to permit usability over a wide range of luminosity (from daylight to dark)."

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Outdated you say? What other cell phone has an LCD panel with 16.7M colors? Show me one that is publicly available and I'll personally refund your N900 purchase! For f. sake, MacBook Pro (and all the older iMacs) has a worse screen than the N900 (same kind of panel, but much lower dpi), and it is used on a daily basis by those who claim to be graphics professionals.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Easy. Every LCD smartphone done until today has been 65k.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

hey so instead of an argument how about we find out how to fix the issue, how can we change the bitdepth to show more than 65K cuz this is really bothering me, esp if the screen and OS are capable id at least like to see the downside for myself.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Can anyone help this situation out? I mean do we know which cfg's control bit depth?

Re: Screen Colours / Color Depth: 16 million or 65K?
 

You cannot change the bit depth, unless you want to break all the software on your device - framebuffer is set to 16bit, and all the applications expect it to be, which is quite reasonable - using 18bit instead of 16bit is an entrance to a whole world of pain when it comes to programming and no sane programmer would use it.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Changing the depth in Fremantle would break hildon-desktop mostly, but not every program.

In the doable realm is trying to show something in the LCD at a higher depth than 16bpp (NOT the system UI), AFAIU the controller supports 24bpp framebuffers. How to tell if the actual LCD panel is 16 or 18 is over me though.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

yeah would be great if we can somehow hack this to make the N900 running at 24bits depth without breaking anything. But how?

It's bother-some me so much with the 65k colours.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Gradients can turn out horrible on the screen I've noticed :(

Re: Screen Colours / Color Depth: 16 million or 65K?
 

At least on my summit loaner dmesg reports:

I didn't manage to find any specs on this, but the Fremantle driver code for that panel contains an #ifed-out acx565akm_set_mode() that allegedly handles 16/18/24bpp and this comment:

On the other hand the version that was submitted to linux-omap a couple of days ago doesn't contain either of the above.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Yes I've noticed that too. Especially on Maemo Forum tabs gradient. All become a series of colours stacking up

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Mind to share the command here? I want to see what mine say

Even windows XP running at 32bits colour.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

I couldn't find any info about the panel either, other than it being a Sony "low power" one (thus I really doubt it handles 24bpp). So we don't know what it really handles.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Test for you: http://www.lagom.nl/lcd-test/gradient.php

Before saying N900 screen is bad, go check your desktop screen.

Even my old IPS gaming display (NEC 20WGX) is not perfect in that test. Looks clean on 2490WUXi... and hence the price.

I'm more than happy with a current color depth since I can't really tell the difference for normal use case.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

??????????????????????
gradient is quite visible on mine. Badly blocks with even the black and white picture. My Dell Monitor with a crappy machine that cant even watch Youtube still produce better gradient than my N900.

This picture below is from a crappy no graphic card PC.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

this is from n900

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Now let see how you going to counter this? A picture worth a thousand words. So please do not say 16bits colours is better than 32Bits colours even without any graphic enhancement.

Take a look and compare..

This is from my crappy 10years old PC...

Re: Screen Colours / Color Depth: 16 million or 65K?
 

That's normal, one uses 24-bit palette, the other 16-bit so you'll of course have visible blocks with a lesser number of colors. But you'll have the same view on all hand-held devices featuring LCD screens out there.

However, try to snap a photo with a high-quality camera if you want to actually see the real quality of the screen. Or lower color depth to 16-bit on your desktop machine and then try to compare the screens. Or compare the N900's screen with some other cell-phone/MID device with an LCD screen and you'll see how good actually is the N900's screen.

Grabbing a snapshot DOES NOT show the screen quality, but a framebuffer that is yet to be sent to the screen via the graphics card.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Mind to do that then? I don't have camera lying around. This is why this post say 16bits!! and 65K colours! If the OS can boosting to 24bits or 32bits even better, then those blocks will be less. Linux can do that too, not just windows, changing graphic depth is all depending on the graphic driver. But why on earth didn't NOKIA by default set it to 24bits or 32bits? May be because Nokia doesn't have the right driver?


Beside, sharpness is not better quality screen, quality screen doesn't always depending on the sharpness of the picture, it also depending on rendering colours and depth of the screen as well.

You can have a sharp screen with crappy rendering and it won't be any quality to it. Take a look at a black and white!! Will you say black and white screen a good quality screen? The screen can be good but there is the colour is not real then it is not a quality screen.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

We're telling you that _YOU_ DON'T have a 24bpp lcd _anywhere_. Your desktop's TFT is hardly 24bpp (most probably 18). Mine's 18bpp. And I've seen +$1000 flat tvs with a 14bpp panel! And 32bpp output is nonsense.

I personally CAN'T see the difference between 16 and 18bpp and thus the reason I'm asking for a conclusive test. A gray gradient just doesn't cut it.

Pretty funny you mention it, because Yes. Gyricon or eInk are so good.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

I don't have a high-quality camera capable of capturing such details, but I have a professional calibrated S-IPS screen (which goes way above the standard NTSC color gamut, 128% to be precise) which dwarfs any MVA/PVA and TN-Film LCD panel out there, and of course it will look way better than on the N900. But it is foolish to compare such a screen to the N900's... You seem to have some heavy misconceptions about the display technology.

1) There is no such a thing as 32-bit color depth when it comes to screens. For a real 32-bit color palette (that is 8 bits per color + 8 bits for the alpha channel) you'd need to have a screen that is capable of achieving alpha on its pixels, and so far not even commercially available transparent OLED screens cannot do that. 32-bit was chosen for the exact same reason as 16-bit is used on the N900 even tho it is able to handle 18-bit - ease of programming. 32-bit is a size of an unsigned integer in almost every programming language, and 16-bit is unsigned short (and 8-bit is a byte), so you can easily manipulate pixels as numbers, in a computer and memory friendly way without non-standard bitwising overhead. Of those 32-bit that Windows reports, only the lower 24 bits are used (R(8b) + G(8b) + B(8b)) - alpha channel is completely ignored.

2) N900 has a TN-Film LCD, just like all the other smartphones out there with an LCD screen (and 99.5% laptops as well), and TN-Film cannot show a 24-bit palette - it uses 6 bits per color, hence it cannot physically show more than 64 levels per color, and thus the maximum color depth it can show is 18-bit, or 262144 colors (R(6b) + G(6b) + B(6b)). You can set the frame buffer to 64 bit if you like, but the screen will show only 18-bit. You cannot physically have more colors than that on N900. And you cannot have more colors than that on cheapo desktop monitors as well!

3) 6-bit is a non-standard data size and it would be extremely difficult and impractical to use it. As I've said, no sane programmer would want to change every single graphic library to accommodate such non-standard behavior. There are three possible approaches to using such a display:

1. To use a 24-bit frame buffer, where the screen's controller would try to interpolate the unavailable colors by dithering methods
2. To use a 18-bit frame buffer where you'd have a huge processing and programming overhead working with non-standard data types
3. To use the first lower-depth frame buffer of standard size, which in this case is 16-bit (R(5b) + G(5b) + B(5b), the highest bit is ignored), where you have no overheads.

While the first solution could potentially result in a better color reproduction (you have physical access to four times more colors than when limited to 16 bit), and which is precisely why it is used on desktop computers, you need to put the things in the right context - a mobile device does not have necessarily enough power and/or memory to handle such overhead gracefully, and the more data needed to be processed eats more battery. Further, you don't have a luxury of a high-powered graphic card (graphic cards in computers of today, even the cheapest ones, usually feature a high-powered RAMDAC working on 400+MHz - by itself its almost as powerful as the CPU of N900) and huge amount of memory so you can waste a full byte per pixel (on N900's screen that would be 384kb overhead, and trust me, that is a lot for a mobile device), and displays themselves have powerful controllers for dithering that eat more juice - and all that while you don't have to worry about extreme miniaturization and without concerns for battery usage.

The second approach is so silly that, to repeat, no sane programmer would consider it.

So, the third option is the most practical for a device such as N900. Yes, you get a lesser number of colors, but you massively gain on the performance and battery life, which is in this use case much more important than being able to show a full-available color fidelity on such a tiny screen. Nobody will do serious graphic work on the N900, actually nobody would do it on a TN-Film screen even if dithered, so I don't see what's the problem there. Sure, N900 could theoretically do it, but Hildon would probably need to be rewritten, there would be a serious performance impact, and I'm not clear whether there is a ditherer within the screen controller in the N900 at all, so that would probably need to be written as well further adding on the performance impact; I won't even comment how would that affect the battery life.

You couldn't be more wrong. Color fidelity is but a note in a long list of requirements for a quality screen. Quality screen does not need to be color at all, there are far more important properties to be considered first - a quality screen may not do all the things possible, but what little it does, it does on a professional level in an appliance that needs those properties. For a CAD designer screen geometry, sharpness and precision are of utter importance, for a print designer correct color reproduction is imperative, for trade shows the most important aspect is angle of viewing etc. TN-Film screens try to do a bit of everything, and they excel at nothing except the price and power consumption - which is actually a quality in the context of mobile devices where aforementioned qualities are not as much important.

So, with everything said, N900 has an exceptional screen for such a device. And there is quite a small number of mobile devices with a screen on par with N900's - and none of those has higher color palette (except those featuring OLED screens, but then you get other issues such as inability to see anything on them in a brightly lit room or under a direct sunlight, seriously crippling them as mobile devices).

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Noticed one strange thing,if you view the picture in Photos app then gradient is noticeable but if you make is desktop background then the it looks perfect as pc.So does it mean the Photos app dispalys 65k and desktop background displays 16 million??can ant boday confirm it?

Re: Screen Colours / Color Depth: 16 million or 65K?
 

maxximuscool, do you realise that screenshot is irrelevant and will depend on monitors people watching it on? ))
It only matters for yourself.

I'm only saying that most people won't tell the difference without testing display.
It is a quality/price question, there is always tradeoff and 24 bit capable screens just don't fit into mobile budget.

p.s. also most budget LCD screens doing hardware dithering to cover the lack of color depth.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

Photoshop tries to draw "real" colors, windows likely applies dithering to make it look smooth with colors you are capable of displaying.

Re: Screen Colours / Color Depth: 16 million or 65K?
 

See the difference