In their press release, +LG Mobile states, quoting:

accurate colors and clear images without any distortion

Here are measurements of Korean G2 F-320K display that +Erica Griffin has for review.
What I see in those measurement is a different story that what the manufacturer states.

Some diagram interpretation:

CIE gamut and saturation view:
First thing, gamut is a bit larger than sRGB standard with green reaching further, on y axis mostly which means maximum green will be a tad more intense, it's not too bad and as-is will probably just look nice.
However if you look at the saturation, something is happening here:

Green and Blue channels mostly are extremely compressed.
As a result, green at 75% saturation is above sRGB standard coordinates, blue at 75% saturation is not much different from 100% blue.
Cyan gets the same treatment as green and blue.
Red saturation is less compressed, LG was more careful here as it's easy to make people's face look red so people identify this as over-saturated colors immediately.

Gamma and Luminance curves:
Gamma constantly above 2.2 which is the usual calibration target, and about average of sRGB standard.
Average gamma value ends up at 2.46, with an actual contrast ratio of 1097:1 (dynamic contrast neutered)
What does that means? You can see the result in Luminance diagram: the image looks artificially too dark.
It's not that bad when you're in dark viewing conditions, but kinda extreme for a smartphone you will use also in bright viewing conditions: making some things hard to see.
Making the image darker also automatically increase color saturation.

White point temperature:
It seems LG chose D75 illuminant here as target (7500K) even if a spectro would be required to give a perfectly accurate reading.

My conclusion here is clear:
LG say what people and the press want to hear: "accurate colors" but does something else.
They're also surfing on the urban legend stating that IPS displays have accurate colors, bashing their Samsung in the process (which is well deserved on some aspects). Yet aren't they're trying to mimic them at the same time?

Both selective color saturation increase and gamma and darker response curve are here to make the image pop regardless of color accuracy.
Those two elements seem like an attempt to make this IPS display look like an AMOLED panel, or at least a "vibrant display".

It might look good to some buyers but please, LG, don't state you're calibrating your display for accurate colors […] without distortion while you're applying processing with a very specific agenda, that has nothing to do with color accuracy.

Will the non-Korean G2 have displays that are targeting color accuracy?
We'll know that in a couple days.

#supercurioBlog #display #measurements #color


In Album LG G2 display measurements (Korean F-320K)

Source post on Google+

New +YouTube Android app is nice and all with all the cool UI features but its video scaling is a joke

The update doesn't use a video surface anymore which leads to several issues:

– Poor bilinear scaling on most devices or no scaling at all (nearest neighbor) instead of the hardware scaling which is usually extremely high quality (lanczos or better) even on low end hardware that comes automatically with video surfaces.

– colorspace conversion issues leading to banding, black & highlight crushing or clipping as reported by a kind follower on twitter.

I get that multitasking is nice, but compromising with video quality is never a good idea.

Note: When you take a screenshot of your tablet displaying a video surface, you get a software conversion that is not what's actually shown on display by hardware decoding and scaling.

#supercurioBlog #video #YouTube #scaling


Source post on Google+

Calibrating my Nexus 7 (2013) to standard sRGB 6500K

First attempt & beta profile

I'm currently writing a solution that will, as absolute first on market to calibrate your tablet using a colorimeter or spectrophotometer.
No erratic slider tuning here, this is the real deal with 256 values per channel.

With this solution, Nexus 7 (2013) will becomes a tool of choice for professional photographers and graphic creators to showcase their work on the go, thanks to a display that might rival their desktop monitor in terms of color reproduction accuracy.
As there's always variation between devices in production, the key is to allow the user to calibrate his device on his own.
(It requires having access to a sensor)

So far, color calibration has not been a priority of +Android Developers or manufacturers:
Most devices are released without any calibration effort, and Android OS doesn't provide any solution to the situation either, being incompatible with ICC profiles.

I'm very early in the development of this solution as I got my tablet yesterday, but in the meantime, here's some measurements with a profile targeting D65, the standard sRGB white point.

+Romain Guy there's a few photographers in your dev teams. Do you think anyone would be interested integrating such feature in Android?

– Contrast ratio is 1103:1
– This is my very first attempt, I'm sure even better results can be obtained.

#supercurioBlog #calibration #display #color #development


In Album Nexus 7 (2013) first D65 display profile

Source post on Google+

Got my Galaxy S Wi-Fi Player 4.2

Its globally convincing (zippy, IPS display with alright color rendering, no obvious bug/flaw) especially for the price: I bought mine for 139€ shipping included on +eBay .

But it sounds a bit off to me so I had to measure the output.
RMAA measurements show THD and IMD+Noise higher than any WM8994 / WM1811 device I tested so far 🙁

My ears are just too sensitive: ruins listening experience. grrr.

You can compare to stock unmodified Nexus 10, powered by the same #WolfsonMicro #WM1811

#supercurioBlog #audio #measurements

RightMark Audio Analyzer test : Galaxy S Wi-Fi 4.2 Volume Max
RightMark Audio Analyzer test : Galaxy S Wi-Fi 4.2 Volume Max

Source post on Google+

Which kind of display and audio performance can you expect from a 99€ Android Gaming tablet

I found the DEA Factory MyPlay one around here and was curious to measure what can be expected such a cheap device.

So here's a few observations I share with you today.

#supercurioBlog #measurements

DEA Factory MyPlay gaming tablet audio and display observations

Source post on Google+

Don't miss my review of Galaxy S II audio performance :)

#supercurioBlog #audio #measurements #article

Samsung Galaxy S 2 (International) Review – The Best, Redefined
Intro. We’ve asked Francois Simond (supercurio), creator of the very popular project-voodoo and voodoo-sound improvement packages, and Android hacker focused on sound, video, and image, to set the…

Source post on Google+

Work in progress in my Screen Tuning app

Satisfyingly accurate hardware color profile for Samsung Galaxy Tab 10.1

White point is changed to 6500k instead of its native 8200k, without reducing gamut.
Take a look at the resulting Delta E 😉

#supercurioBlog #calibration #color #display


In Album Working on a 6500K profile for Galaxy Tab 10.1 (9 photos)

Source post on Google+