My app is downloading images from url and sometimes these images are completely transparent with size 600 x 400 pixels or even more. I would like to detect such images and ignore them. Is there a way to do it?
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I am making a game sorta like cookie clicker, and I want the images to look 8 bit. I use a macbook pro retina, which has four pixels for every one pixel on a normal screen. On Chrome and Safari, instead of each pixel being represented by 2x2 pixels, I get a bunch of blurry blobs... I don't have this problem on FireFox. There's this one website called pixeljoint.com that is made for pixel art, and I don't have the blurry problem there. Whenever I open one of the images from PixelJoint in a new tab, the image goes back to blurry. I heard that the problem is that the images are scaled before they are displayed on chrome and safari, but I'm not too sure.
Here are two screenshots to show what I'm talking about:
I would also like to point out that the images are normal .gif files.
I am aware that you can convert a gif file to an svg with this link
and an svg file looks fine on retina.
All I want to know is how PixelJoint makes the pixels look so smooth.
I figured it out, you need to use CSS!
<style>
img {image-rendering: optimizeSpeed;image-rendering: -moz-crisp-edges;image-rendering: -webkit-optimize-contrast;image-rendering: optimize-contrast;image-rendering: pixelated; -ms-interpolation-mode: nearest-neighbor; }
</style>
I found this in the source code, so I guess this is how PixelJoint does it.
I created an extension for Firefox and made a simple icon for it.
But when I tested it in the Addon manager the icon appeared blurry despite my source image was fine.
I started to experiment with different sizes and shapes of the icon.
Figured out that the icon container is 48x48 pixels and the default addon icon is 32x32.
But for any experiments the result was the same.
So I created a simple rectangle icon drawing it by pixels so it shouldn't blur anyway:
But the result blurred again:
There is some sub-pixels around the rectangle though the border should be crisp...
In pixels view:
Also I found the default extension icon (a puzzle piece) and in pixels it looks perfect but in the manager the borders are blurred a little though it's not obvious at first glance.
Are you sure this is not happening when you save the image? I don't know what app you are using, but many photo apps try to compress jpm images when you save them by default. Check this first.
Usually this does not happen with png images, so you could try using a png image instead as well.
It was silly enough... The broblem was the page scale not 100% on the Addons page. Pressed Ctrl+0 and all restored.
It happens sometimes on other web pages when I zoom in/out the view and images lose their sharpness.
We have a sprite of many icons which is 10564px x 80px. The icons are arranged horizontally.
In every other browser except IE10 the icons/images show up when being used as background images for tags with specific CSS to apply the relevant position.
When viewed in IE10 they do not show up at all and actually when you try to view the png file directly from the URL in IE10 it doesn't show either.
Any ideas?
After extensive testing, it turns out it's a limitation on the width of the PNG canvas and IE10.
PNG images would work and can be viewed right up until 8000px wide but no more than that, after that they just don't render.
After more testing it's related to whether or not they are transparent. PNGs with transparency just don't show at all whereas images without transparency show as a black block (canvas).
Whether or not MS will fix this remains to be seen... we live in hope!
The fix for us is to reduce the width of our sprite to 8000px and have two or more rows of icons/images well spaced out.
The fixes is only to separate the each individual image as single with minimum size, which will be less than 8000px wide;
I am trying to reference images with a greater height than width (portrait format) in KML script for Google Earth; however, the image always comes out as landscape, or rotated left 90 degrees, e.g.
<img id="id_photo" src="2012_01_21-dscf03.jpg" width="500"></img>
I've tried everything I could think of. Is there a image tag to correct this, e.g., format="portrait"?
Thanks,
Walter
This sounds like an example of EXIF only rotation. Which GE probably doesn't honour.
Some cameras etc, 'rotate' a image so its the right way up by setting a flag in the EXIF data. The raw JPG itself, is still in the landscape format.
A display (or convert) program, should hopefilly notice this 'rotation required' flag, and rotate the image.
But Google Earth probably doesnt honor it, so you are just seeing the baseline image as its actully stored (unrotated)
Recommend trying one of the applications mentioned here:
http://jpegclub.org/losslessapps.html
(many note they have automatic correction - so should "fix" your jpg files)
This is already an old thread, but I stumbled on the same problem. And did not find a solution for my situation. Eventually I found a way around, so I thought I'd share it here.
Basically the solution is to rotate the offending images twice, once 90° to the left and then back again.
What you had was an image with a width larger than the height, but with an orientation tag that tells an application to rotate it 90° (but Google Earth does not).
After rotating it twice it is an image with width and height switched, and an orientation tag that says not to rotate it.
Now any application, including Google Earth, will display it correctly.
I used ExifTool to write the tags for all my images to a CSV file, created a list from that with all the pictures to rotate, and used that list to tell IrfanView twice to rotate them.
I have an application that is set in landscape mode because of the content it contains. One of the things I want to do is take a picture of a piece of paper. I present the UIImagePickerController locked in portrait mode because it fits the paper size. After the user takes the picture I load that image as a background on a UIWebView. The reason I use a webview is because sometimes I need to load a .pdf there as well. Anyway, I'm setting the background using CSS. Here is the code...
//img is the path to an image.
myHtml = [NSString stringWithFormat:
#"<html><head>"
"</head>"
"<body><img src='%#'></body></html>", img];
[resume loadHTMLString:myHtml baseURL:baseURL];
The problem is, the image is displayed in landscape when the app returns to the UIWebView. Everything else is normal as far as text etc. Is there some reason that images are rotated 90 degrees to fit properly or something? I have tried pretty much everything with no luck.
The other thing is that we I retake a picture and reload the webView the old image remains.
You need to change the orientation of the image from its exif header if there is orientation info available in it. Identifying the picture orientation is the hard part, rotation of imgs can be done easily using css -webkit-transform: rotate(-90deg);
It does have to do with the exif data. While using a webkit transform may be ok for use in just the web view once, if you want to use the image later and have it always be the right orientation I'd use the categories given here:
http://vocaro.com/trevor/blog/2009/10/12/resize-a-uiimage-the-right-way/
The article does a great job explaining exactly why the rotation occurs and the code does a nice job of 'fixing' the 'problem' so that you can then make use of the image without having to do extra things or worry about whether it'll be displayed correctly (even though the UIImageView takes the orientation into account).
You can resize with this to the same size it originally was, and it should fix the orientation issue.