I just started to study android so I barely know android library.
Would you introduce some library so I can figure out the problem?
The reason I'm trying it is that there is no available parameter to manage shutter speed.
I would like to exposure image sensor a long time but I found it's not supported by firmware.
So I planned to record a video and cut it. Then, combine it together so it would be like long shutter speed picture.
Thank you for reading
I don't really understand what you're trying to do.
How capturing multiple frames will allow you to simulate different shutter speed.
Assuming you know what you're doing, check out this SO.
You can start recording for any time period you want, save all the images to files/memory and then do whatever you want with the frames.
Related
In one of my application i need to record video of my own screen.
I need to make a video in that user can take video of their app how it possible?
first question is it possible so? if yes then how? any useful links or some help
Thanks
Pragna Bhatt
Yes, it is possible, but with certain limitations. I have done it in one of my projects.
Android 4.4 adds support for screen recording. See here
If you are targeting lower versions, you can achieve it, but it will be slow. There is no direct or easy way to do it. What you will do is, create drawable from your view/layout. Convert that drawable to YUV format and send it to camera (see some library where you can give custom yuv image to camera), camera will play it like a movies, you can save that movies to storage. Use threads to increase frame-rate (new multi-core device will have high frame-rate).
Only create drawable (from view) when there is any change in view or its children, for that you can use Global Layout Listener. Otherwise send same YUV image to camera.
Limitation:
You can not create video of more than one activities (at a time), or their transactions, because you are creating image from view. (Work on it yourself, may be you'll find a way)
You can not increase frame rate from a certain point, because it depends on hardware of your device.
In Android Studio we can both capture and record screen on our devices. When capturing the screen we have the option to directly frame our screenshot in device art or use online tool http://developer.android.com/distribute/tools/promote/device-art.html
When Recording Screen there is no option to frame it in device art and Google don't seem to provide any online option either.
What would be the fastest and easiest way for developers that want to showcase their screen recording in a frame from device art where a new video is created where device art is wrapped around our screen recording.
Give away your best tip. I would love a fast, free online service that solves this and guess there is one out there.
I've spent a substantial amount of time researching, but could also not find a service for it.
I have however written a guide for how to record screen, add device frame and convert to gif, which you can find here:
http://appdictive.dk/blog/how-to/2015/04/20/google_plus_gif/
The short version of it is:
Record screen
Get Device frame picture
Use Photoshop or other video editing software to add the frame as static picture to the video (guide briefly shows how to do this in Photoshop).
Hope this helps others searching for a solution to this as well.
There are very few services I've come across on the web that allow you to simply upload a video within device art frames, especially free platforms. However, if you have video editing software such as Adobe After Effects, you could import images and videos and create this yourself; albeit added cost and time against the earlier option.
Despite the above, I've managed to utilise Google's Device Art Generator page to extract the device frames they offer quite easily. All you need to do is create a solid background colour in Adobe Photoshop (as an example), say bright green, followed by uploading this to the generator. Download the image generated with the device art applied with the solid fill colour and then use the Magic Wand tool in Photoshop and simply delete the solid colour. With this in mind, the next course of action is to simply insert the video using After Effects in the transparent space now available. This is even a bit overkill, as you only need to overlay the video within the screen dimensions of the generated screenshot from Google, yet this gives you an idea of how you could achieve what you want.
I had the same problem and ended up writing an app to do that:
https://play.google.com/store/apps/details?id=de.mobilej.recapp
It works completely on the device - no plugin or desktop version yet. It needs Android 7.0+
I'm the author of the app - so sorry for referring to my own app.
Is it possible to record screen video of current running activity from same activity ?
I know how to take screenshot of current activity but don't have any idea about taking screen video record. How would I start with it ? I don't know how to start it.
There are no APIs yet in Android to do this directly. However, you could take screenshots of the app, and then merge them to make a video out of the images.
However, this process is quite tedious, and would probably take a lot of research and investigation.
Since you know how to take screenshots, a good starting point would be to look for libraries/APIs that can take in a series of images, and convert them into a video.
ffmpeg/JMF could be two good starting points.
After a lot of searching and days of experiments I haven't found a straight-forward solution.
I'm developing an app that user will interact with a pet on the screen and i want to let him save it as video.
Is there any "simple" way to capture the screen of the app itself?
I found a workaround (to save some bitmaps every second and then pass them to an encoder) but it seems too heavy. I will happy even with a framerate of 15fps
It seems to be possible, i.e. there is a similar app that does this, its called "Talking Tom"
It really depends on the way you implement your "pet view". Are you drawing on a Canvas? OpenGl ES? Normal Android view hierarchy?
Anyway, there is no magical "recordScreenToVideo()" like one of the comments said.
You need to:
Obtain bitmaps representing your "frames".
This depends on how you implement your view. If you draw yourself (Canvas or OpenGL), then save your raw pixel buffers as frames.
If you use the normal view hierarchy, subclass Android's onDraw and save the "frames" that you get on the canvas. The frequency of the system's call to onDraw will be no less than the actual "framerate" of the screen. If needed, duplicate frames afterwards to supply a 15fps video.
Encode your frames. Seems like you already have a mechanism to do that, you just need it to be more efficient.
Ways you can optimize encoding:
Cache your bitmaps (frames) and encode afterwards. This will work
only if your expected video will be relatively short, otherwise
you'll get out of storage.
Record only at the framerate that your app actually generates (depending on the way you draw) and use an encoder parameter to generate a 15fps video (without actually supplying 15 frames per second).
Adjust quality settings to current device. Can be done by performing a hidden CPU cycle test on app startup and defining some thresholds.
Encode only the most relevant portion of the screen.
Again, really depending on the way you implement - if you can save some "history data", and then convert that to frames without having to do it in real time, that would be best.
For example, "move", "smile", "change color" - or whatever your business logic is, since you didn't elaborate on that. Your "generate movie" function will animate this history data as a frame sequence (without drawing to the screen) and then encode.
Hope that helps
I write an application for Motorola Xoom tablet with Android 3.1 for my master thesis that can scan multiple QR Codes in real time with it's camera and that displays additional information in the display over recognised QR Codes.
The recognition is done with the ZXing android app (http://code.google.com/p/zxing/), I basically just changed the code of the ZXing app so that it can recognise multiple QR Codes at the same time and can do this scan continually, without freezing after a successful scan like the original app does. So my app is basically the ZXing app with continous scanning of multiple QR Codes.
But I'm facing a problem:
The recognition rate of QR Codes with the built in camera is not
very good. The ZXing app uses the pictures that it gets from the
camera preview. But these pictures do not have a very good quality.
Is there any possibility to make the camera preview making better
quality pictures?
P.S. I also tried to make real snapshots with camera.takePicture()
to get a better quality, but it takes too long to take the picture
so the real time experience for the user is lost.
Any help is highly appreciated!
Thanks.
Well, the question would be... why is the image quality that bad? Do the image have low resolution? Is the preview out of focus? I've worked with the ZXing Android app before and I know that it has a mechanism to keep the camera auto focusing the live scene.
If the auto focus mechanism is undergoing, then you are possibly decoding some images that might be out of focus. Rationaly, it would make sense to decode only when the camera is in focus, but that would delay the decoding process, since it would have to wait for the focusing to do the image processing phase. However, I wouldn't be too much worried about this for several reasons: 1) the auto focus is very quick, so there will be very few blurry images (if there are any at all), 2) the camera keeps focus for a sufficient amount of time that would allow for a couple decodings, 3) QRCodes typically do not require perfect images to be detected and decoded - they were designed that way.
If this is a problem for you, then disable the continous auto-focus and set the parameter to anything that suits you.
If the problem comes from low resolution frames, well increase it..., but QRCodes were also designed to be identified even in small resolutions. Also, keep in mind the increasing the resolution will also increase decoding time...