I implemented an application for image zooming based on this tutorial, and it works well.
However, when I zoom in on the image, it loses its clarity. I want to have image zooming that preserves quality and clarity. How can I set that up?
If I understand your question correctly, then awoodland's comment is right, and this is impossible. Despite what TV crime shows use as plot devices, you can't get infinite clarity out of any photograph. If you could, what would stop you from zooming in on any photo repeatedly until you got down to the molecular level?
When you zoom in on a digital image, what you're really doing is ignoring parts of the image and only looking at a small section of it. If you're starting with a zoomed-out image, then zooming in is like unfolding a crumpled-up dot-matrix printout and cutting out a square in the middle to look at; there was more information hidden in the crumpled area that you couldn't see before. But once you "unfold the paper all the way," that's it. If you try to look closer, you can make the individual dots (or pixels) bigger, but you don't get any more useful information because it's not there to begin with.
Converting to a vector image won't help you because of how vector images work. They save the relative positions of important points and then put down whatever size lines and shapes are needed to make a given size work. You can't reverse-engineer the rules from a single static image.
For example, if the top half of a 500px tall photo is solid blue, it could be because a rule says the top 250px of the image should be blue, or it could be because a rule says the top half of the image should be blue. If you're automatically converting to a vector image, the computer has no way to know which of those rules is correct, or if you happen to be looking at a special case of a much more complicated rule. As a result, your generated vector image would expand in completely inappropriate ways.
Related
I am working on a widget, where I need to have a chart displayed in addition to some text fields. I have figured out how to generate a visualization of the graph and then convert it to a bitmap, which gets placed in the ImageView. The problem is the following:
In a normal Android app, I would get the width and height of the ImageView and pass these as parameters for the bitmap generation. This way, the image will be fitting perfectly within its container. Since I am using a home screen widget, this is not possible, as far as I am aware, though. As a result of this, I am trying to derive the size of the ImageView by trying to figure out what size would the text fields have, but I also have to calculate those and so far have had no luck with getting it right. What I end up with is always having excess space above and beneath the image, or on its sides and the size of this is really varying according to the screen the widget is presented on. You can see some examples in the two links below.
Example A This is the default widget size. For this screen, only a small gap can be seen on the sides of the graph.
Example B Resizing the widget and recalculating the size leads to having bigger gaps on the two sides, though. For other screens the issue can be even more jarring.
My question is:
How could I get/calculate the necessary resolution for my bitmap?
Good day guys.I want to make the bottom part of my own image an curved line.Not to talk back and forth here is an image which i want to get into the application.
Important to notice that i have reached 10th result of the google and everything i came up was only some curved image not in my desired way,the whole image was curved and the lines of 4 parts were connected to single one.
So basically i want the image to be as rectangle as it comes from server and only curve the bottom part of a bitmap.Is that even possible?
Noticae the bottom line is curved,that what i want to achieve,and rest parts are rectangle.Thank you for your time.
If you are trying to change the image itself, photoshop or any editing tool is the right way to do it. besides if you are getting the image from a server somewhere then getting the image adjusted from the server, instead of modifying it on the client side(o your app) has lot of benefits.
But, if want to change the look not the image itself, then that could be achieved by creating a custom image view like answered here.
You can also use a card view hold your image view to achieve some curves, although i don't think that would be efficient or satisfactory for your case.
Sometimes, editing the image in Photoshop is the right way. This can save your android app CPU time.
I am working on an application in which I am using a frame layout. In the frame layout there are three classes as follows:
creating image
checking the pixel of the image the user touches
drawing the image
But when I am touching on the same color, it is giving me a different color value. If anyone wants to see my code then it is there. If you want to check which image is used by me then the images are as follows:
the second image which is used for getting the pixel:
Can any one tell me why it is not giving me correct value of the color on touch on the image
?
Edited1
my edited code of the imagein class is as follow [code after editing4
My guess is that you are making assumptions based on the the pixel coordinates of the image, and not translating the coordinates as they exist once Android resizes your art. You should see what Android thinks the image size is, after it's drawn to your View and make sure that the spot you're touching is the same spot that you're expecting to be touching.
I am wondering what would be the best practice for android. To draw or to load an image?
For example I want to have a circle that is green filled with the text 25 in it.
-Should I have it in .PNG image file and just load it to the imageview placeholder when I need it?
OR should I load it in Java (by determining the position in java and load it from my res folder)?
OR Should I draw it (draw a circle, fill color, add text field inside)?
On another note, to have a checkmark, what do advise me to do?I don't even know how to draw that
I really need your help in this
Thank you so much
I'd actually argue that there is a single right answer. You should use a shape with a set color and text view inside it. It is easy to do what you've described in xml, see: Oval Gradient in Android for an example (there are a number if you google for android shapes). This will be less CPU/memory intensive than loading a bitmap, and more importantly, it will work for and look good on every screen size. As an added bonus of the user has changed their default font sizes, a textView/shape can respect that and a static image can not. Just set the background of your TextView to be the shape drawable (either in xml or programatically).
To get a bitmap to look good on multiple devices (a must for android development) , you will need a number of different versions of the same bitmap at different resolutions (XHDPI, HDPI, MDPI... etc).
Check marks are harder because they don't conform to a standard shape. Those you probably will have to make pngs for.
It depends on what you want to do.
Rendering a bitmap will be faster, but you cannot manipulate it after it is drawn.
So, for your case, you have a green circle with 25 written it. Do you also need a green ball with 23 and another with 24 in it? What about other colors?
It really depends on the amount of variation you need. At a certain point the overhead of using dozens of images will not be worth the evert of drawing to a canvas. Or, depending on how complex the images are, it will be.
The question is not "Which is better?", but instead, "Which is better for what I need to do?"
I'm not an expert on Android development but after seeing your question I have done a bit of reading and came across this article on displaying images with android that is relevant and includes some code to possibly help you out. http://www.javacodegeeks.com/2011/07/android-game-development-displaying.html
As for your image of a check mark, why dont you just go into photoshop or paint and use the line tool to draw a checkmark and then fill it in with color and save it as a .png perhaps?
I'm entirely new to Android development, and I'm interested in making a live wallpaper. I was thinking about looping a set of pictures instead of drawing the animation. Is this a possible approach? If possible is this a suitable or ideal way of doing it, does it eat up memory and would i need images with different resolutions because of the fragmentation?(hundreds of different devices)
Thanks in advance :)
Sure, it should be fairly simple.
The main part of the Wallpaper engine is the Drawing of course. You need to handle the drawing manually, there is no easy way to loop through images... you need to code it. You will have to continuously monitor the time which has passed and adjust the displayed image based on that. You are given a Canvas object to draw to and it is all done during run-time in code.
The Wallpaper engine class has a event called onSurfaceChanged which gives you the width and height of the Surface which you will be drawing to. It will be called everytime the screen dimensions change (like if the phone is put into Landscape mode for instance). You need to have code that will handle any combination of width or height for all the device types out there. You will need to decide if you are going to stretch, center, tile or crop (Or a combination of those) the source images to fit any particular screen size. I would recommend scale to fit so that the image is either taller or wider than the screen and center the image either vertically or horizontally (cropping the extra bits) once that is done. I personally just use one source size and resize it to fit. You can opt to use several source files if you want which is the recommended approach I believe, but it's a little confusing.
I would start by creating a Live Wallpaper which just draws something basic like a shape to the screen. Then work out how to display an custom image and take it from there.
Good luck
You will need to be very careful about memory if taking a frame approach to animation--probably will not be possible to animate full frames--much more practical to move sprites on a background. See, fr'instance: http://davidjhinson.wordpress.com/2010/05/19/scarce-commodities-google-android-memory-and-bitmaps/
what if you have a png frame animation that is set at a certain x and y position that sits in a spot on the background image, both would have to be rescaled