I am connecting my Nexus 4 to a projector - but the resulting image is trapezoidal due to keystone. I want to be able to control this using software such that the image that goes out of the android is already corrected for this problem (In such a case, the projection will get smaller for the wider edge of the trapezoid and will be equal to the narrow edge; the remaining area can be black pixels.) There are two things to do here - one is the actual algorithm for keystone correction, which I think I have found here - Algorithm for software keystone correction. Any other efficient algos? And the second is how to modify the displayed screen in android to the one I want to send (if I were somehow able to change the android screen resolution to a trapezoidal value!). I don't mind distorting the phone display as long as the projected display is good. Also, would prefer this for any running app, not necessarily my app. Thanks a ton!
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First off, grovelling apologies for what is probably a painfully newbie-ish question - I am entirely new to Android phones. I have tried searching - came across this thread, for example: http://forum.xda-developers.com/showthread.php?t=1124669 - but haven't found much in the way of practical solutions yet. This may conceivably be more of an "Android question" than a "Galaxy S2 question" as well, I'm not sure....
Anyway: one of things I use my phone for an awful lot is watching videos. What I'd like to be able to do is get the the display a little closer to a properly callibrated TV - so the whitepoint should be somewhere near D65, proper white balance across the whole grey-scale, the gamma somewhere near 2.2 across the scale, primary colours not too saturated, and so on.
The main problems at the moment seem to be that the white point is pushed quite badly towards the blue, and that the green primary colour is oversaturated (this is in line with the findings in the thread above). So my question is: what can one do about this?
I've investigated the "Display" settings menu, and discovered the "auto-adjust screen power" option which (again, according to the thread above) improves the gamma (reducing black-crush) at the cost of somewhat reducing maximum brightness. I've also spotted the "background effect" option; setting this to "Movie" makes colours a bit less over-saturated, but green saturation still isn't right. And within the standard video-playing application I've got the "colour balance" set to "Warm", which helps with the blue push a little, but not enough.
Are there any other display adjustment/callibration options that I've missed? Are there any apps which allow the display characteristics to be tweaked? And are there any 3rd-party video-playing apps which allow more precise callibration of the overall colour balance without compromising playback performance?
I am working with a partner in developing an app that would go in between the apps and basically control it in order to show a uniform control of the pixels. Basically what we are trying to do is have pixel level control of the display regardless of the content on the phone.
My Questions are:
1. Does the smartphone developer API provide access to the frame buffer of the display, which can be modified for each frame that is displayed on the screen?
2. Does the smartphone have enough time to run a 2D filter on each frame before it gets displayed? Will the phone processor be fast enough that you can filter each image and still keep up with the output frame rate (e.g. 30 frames per second). Each calculation that will need to be calculated takes time for the processor to calculate, but how much? Can the phone do all of the calculations it will need to under 1/30 seconds AND keep up with normal app processing without affecting the overall frame rate. Much of this is based on the software that is developed to solve the problem, so the real question really isn't "Does the phone have enough real time," but rather " is the phone fast enough to handle a garden variety 2D convolution on top of everything it already does".
3. Will this level of control be achievable without root to be able to reach more people with unrooted devices or is this achievable only by root level permissions.
I do hope I am in the right area to post this very important question in the the development process. We need to get this sorted out first before we can begin programming.
All the help would be very much appreciated. Thanks xda!
Hey guys,
I've been working on a small projector using a high aperture camera lens in small box (painted matte black internally) and have tried various mirrors and magnifying glasses to reverse the mirrored effect that is projected. With a mirror the image is inverted back to normal but has some flaws. Without the mirror the image comes backwards. I have found apps to reverse landscape mode so the image projected is upright, but the image is still inverted (text is backwards).
I've mounted a box with the lens on a tripod and I can place the device inside, adjust it to the preferred size and adjust the lens focus till the image becomes clear. The projection is only visible in low light/unlit rooms with even full brightness. I'll share what I've done at some point as soon as the project is complete, I've found it extremely useful already for watching videos on the walls and ceiling, though my main goal is to use it to project images onto a canvas to be traced and painted over. Rather then spend $100+ on a projector, I figured I'd save the money and use what I have available.
I've searched endlessly for a solution. Mirrors and/or additional lenses cause too much light loss and quality distortion. The ideal solution would be to invert the reversed landscape so the projection appears in full brightness, quality and allows the projection to appear "normal"... Through remote access the device could be controlled without removing it from the projector housing.
For static image projection I could manually flip the image, but I'd like to have the entire display flipped for full functionality of all apps, games, movies, etc...
So far I've managed to get a crisp display projected at about 40 inches although the color is slightly desaturated.
Perhaps this isn't something that an app can solve but maybe a custom kernel could.
If somebody were to make an app that did this, I'm sure it would be marketable.
Any suggestions or help with this would be greatly appreciated.
Thanks in advance,
-Kompster
I have a Geniatech ATV1220 android set top box running android 4.2.2 and am using an arduino with motion sensor connected to it to modify content on a website when someone is in front of the sensor via NodeJS.
This works great, but what I would like to do is to manipulte the complete system viewport of the android system. For example if someone steps in front of the sensor, the whole system should be displayed in a reduced size like 1/4 original at the bottom right side of the screen while the other area should just display black or basically nothing.
It is really hard to find something because of the pretty common keywords like display, viewport, size and so on. I could probably do it dependent on individual applications but I also want to use it in third party applications, which I cannot modify.
Currently I am sometimes using commands like this:
Code:
echo 1 >/sys/class/graphics/fb0/blank
to modify the actual content that is displayed, in this case it all turns black/blank and I wonder if there is a similar way to achieve what I want to do. Any help is greatly appreciated.
Do you think it would be possible to achieve variable refresh rate of Xperia 1 mark 3 screen?
I mean display instead of always running in 120Hz or 60Hz would run in 120Hz when scrolling and even in 1Hz or 10Hz when nothing moving on screen (for example reading or watching a picture).
That would help with battery life and reduce the heat.
We could select to always run in 120Hz or in hybrid mode.
Do you think software can do this?
I think it's possible if someone work with software or fw.
the real question is if Sony will work on that (probably not) or if modding community will work on that when and if TWRP or other rom will support Xperia 1 III.
Maybe (but this is just a big speculation) with the new android release google will support variable refresh rate inside Android
Unless the screen can run at those refresh rates, sony can't do anything. if the hardware is not capable, software/firmware can't do anything. My take on this is if our xperia 1 III had vrr screens, sony wouldve already implemented it in their android to take advantage of it. so therefore, our screens most likely aren't vrr and therefore stuck at 60 or 120hz.
as for the 40hz in game mode, the screen still runs at 60hz as per developer settings show refresh rate, so it only reduces the fps of the game, not the refresh rate of the screen.
I think probably we will get the "ProMotion" feature on an update. I hope sony does it.
What is ProMotion feature?
Since this device was released tbh we didn't receive any new feature/function or changes to better for our phone.
Apart from reducing cpu's clock speed to reduce abnormal extreme heating there are either feature removals (like Music - disablement of downloading metadata from Internet) or just security patches... Literally nothing. I still hope for vivid mode for better colors and many updates to camera (4k 60fps in main camera, 21:9 picture s in main camera, night mode, better quality as I noticed some blur on the edges + pics are too soft). Also hoping for better battery utilisation and maybe bring back super stamina mode.
And bring back sony Album and other xperia iconic apps :/
Sony Album can be side loaded from APK Mirror. I loaded it but deleted it because I saw no benefit...YMMV. I believe there are other "Sony" apps available there also.
Indeed it is available and still working, but we do not know for how long it will work, especially after new system updates. Like android 12, then 13 etc