Get image width and height in pixels - eclipse

so i have looked at a couple other questions like this and from what i saw none of the answers seemed to answer my question. I created a program that creates ASCII art, which is basically a picture of text instead of colors. the way i have the program set up at the moment you have to manually set the Width and Height of the pixels. If the width and height of the pixels is too large it simply wont work. so basically what i want to do is have a function to automatically set the width and height to the size of the picture. http://www.mediafire.com/?3nb8jfb8bhj8d is the link to the program now. I looked into pixel grabber but the constructor methods all needed a range of pixels. I also have another folder for the classes, http://www.mediafire.com/?2u7qt21xhbwtp
on another note this program is incredibly inefficient, i know that it is inefficient in the grayscaleValue() method, but i dont know if there is any better way to do this. Any suggestions on this program would be awesome too. Thanks in advance! (this program was all done on eclipse)

After you read the image into your BufferedImage, you can call getWidth() and getHeight() on it to get this information dynamically. See the JavaDocs. Also, Use a constructor for GetPixelColor to create the BufferedImage once and for all. This will avoid reading the entire file from disk for each channel of each pixel.
For further code clean up, change series of if statements to a switch construct, or an index into an array, whichever is more natural. See this for an explanation of the switch construct.
One last comment: anything inside a class that logically represents the state of an object should be declared non static. If, say, you wanted to render two images side by side, you would need to create to instances if GetPixelColor, and each one should have its own height and width attributes. Since they're currently declared static, each instance would be sharing the same data, which is clearly not desireable behavior.

Related

tableau adjust marks size using number

In Marks, click Size and there pops a slider where I can adjust the size of a shape. But how to accurately control the size, is there some property with numbers to accurately control it? I have two sheets to show something similar and I want to display exactly the same sized shapes.
If you want to ensure 'sizes' are the same across two worksheets, I'd suggest snapping the 'size' setting to the center on both, as this is the easiest option to select. You can then use a measure to set the size, if this is desirable, and then the difference in size will be relative on both worksheets.
There isn't a numerical value override for the size slider.
Ben is correct, there isn't yet a numerical value override for the slider. You can use parameters with Min/Max/Sum etc. and a variable to somewhat change the sizes but they have to have multiple entries per line. It is unfortunate that Tableau still doesn't get that people want both a 'relative' sizing system that uses numbers from the dataset and a 'static' sizing system that allows for shapes to be set to '11px' or something along those lines. Yes, you can control that kind of in the dashboard with a vertical and fill entire box etc; but that doesn't address the very real scenario where you want a user to be able to re-size on the fly. Just my two cents.
I ran into this today. Very annoying. Need to keep shapes the same size across all worksheets and therefore same on dashboard.

GtkTreeViewColumn resizing based on contents

So it turns out that we'd like to use fixed height mode, because it's faster and it doesn't constantly try to update the treeview — we saw a significant decrease in CPU use with a table that, unfortunately, may contain a few thousand rows and some 20-ish columns.
Oddly enough, merely turning off autosizing on all the columns doesn't help, one needs to set fixed height mode too.
But of course, the cell contents are of varying length (they're text and numbers), and it would be nice to update the column size time to time (ie. when I know they should be updated, and not all the time like autosizing unfortunately does).
So what I need is being able to figure out that the newly inserted row / cell has insufficient size (I guess something to do with the GtkCellRendererText and Pango will come handy), and then resize the affected GtkTreeViewColumn using set_fixed_width. I've looked at the source of GTK+ to see what they do when autosizing, but couldn't really make head or tails of it. My main problem here is getting to the text layout and/or the cell size requirements from a given TreeView/ListStore/iter combination.
I use perl-Gtk2, but answers are welcome in any commonly used language.

iOS: How to create and draw into (and save) an image larger than the screen?

We're creating an iOS photo app. In doing this, we have to create dynamically sized images up to about 2500x1600px. Once this image has been created, we want to draw smaller images on top of the big one reasonably quickly.
The problem as we can see it is that it's impossible to get a context larger than the screen resolution. The call does not crash, but it returns a nil-context. How can such a seemingly simple task be achieved?
Secondly, once this context is created, what is the fastest way to draw a small image at a given position on top of the big one?
Edit:
We found the solution. CGBitmapContextCreate returns nil because the width and height parameters were set as floats, not ints. Sometimes the solution is right there in front of you, and you're too blind to see it. Hopefully this answer can help other people that somehow have the same problem.
Make sure you specify integer widths and heights as the arguments to CGBitmapContextCreate, otherwise it returns nil. Otherwise, the size of the context should not matter as long as you can malloc enough memory for it.
It should be possible to get a context for almost any bitmap for which you can allocate/malloc enough memory, in your case multiples of 2500x1600x4 bytes of ARGB pixels.
You might also want to look into using a CATiledLayer, where you would only have to draw into the tiles covered by the smaller image. You may have to tile to support older devices which are limited by the max tile size that will fit into the GPUs texture cache.

Is it possible to determine the (pixel-)width of text-strings bevore SVGs are created with scripts

I am about the create a bunch of SVG graphics with (probabably) a perl script. These SVG graphics will contain text blocks. Since I want to "connect" such text blocks (of varying widths) with lines I'd like to know what width a text will be so that I can draw the connecting lines' length accordingly.
I have seen in SVG get text element width that it could be possible with java script. But that's probably not what I am after since I don't intend to host the SVG in a browser.
So, I thought that maybe there's a way to find out the desired width at the script's runtime. If someone can point me to a solution (also outside the realm of perl but on windows), I'd be very gratefu.
I did that exactly that about a year ago using PDF::API2 and advancewidth function: https://metacpan.org/module/PDF::API2::Content#width-txt-advancewidth-string-text_state-
Note that you need to correlate DPI of PDF and SVG: they may be different (I actually did that just dividing values by 1.25, you can be better).
PDF::API2 gives you very accurate values that works for Inkscape (in my case) well.

FlowCoverView How to change tile (texture) size?

I'm using FlowCoverView, an open source (and AppStore compliant) alternative to Apple's cover flow (you can find it here http://chaosinmotion.com/flowcover.m)
How can I change the tile (or texture as it's called in the library) size (statically at least)?
The code comes with a statically fixed 256x256 tile size. This is fixed using the TEXTURESIZE define and hard coding the number 256 within the code.
I tried to replace all 256 occurrence with the TEXTURESIZE define and it works... As long as the define is set to 256! As soon as I put another value, I get white 256x256 images in the flow view (I pass the correctly dimensioned UIImages through the delegate of course) :(
I can't find where in the code this 256 value is used. I repeat: all 256 occurrences were replaced by the TEXTURESIZE constant.
PS
Of course, the next step to improve this nice library will be to make the TEXTURESIZE a property, to be set at runtime...
Use this. It is much easier to implement then yours.
https://github.com/lucascorrea/iCarousel
Change the TEXTURESIZE to 512 . clean the build and run it