I'm using Firefox 22.0 on Windows 7. When I load a scaled png image, the image jitters/shakes a little about a second after it is loaded. What's going on?
<a href="bozo">
<img style="height:45px;" src="http://images.cdn.rackspace.com/header/logo-rackspace.png">
</a>
Here is a jsfiddle. I can reproduce the behavior by clicking Run.
I do not see this behavior on Chrome or IE.
I couldn't reproduce, but it jitters because you set the size (and the wrong) by using CSS.
The image is 46 pixels in height and is first loaded as this, then the CSS is applied to it at 45 pixels which shrinks it by 1 pixel, hence the jitter. This little difference will show on the screen in a glimpse as it also affect the width, perhaps enough visible on some systems to make it appear to jitter.
If you set the image size to 46 pixels it should go away, or by setting the size as attributes:
<img height="46" ...
Related
I have many small icons in my website. Instead of loading all of them independently, I am thinking of using CSS sprites due to performance gain.
Consider the following code
<div style="width: 24px; height: 24px;background: url('img.png') -10px -10px;"></div>
vs
<img src="css-sprites.png" style="width: 24px;height: 24px;">
As expected, both gives same result. When loading as an image (second case), if I keep resolution of actual image a higher value, say 128*128, and using 24*24 for display, I am getting better resolution even when we zoom the page in browser (tested in mozilla).
But when using css sprites, since I have to keep the same display resolution in the sprite, the image gets blurred when zooming.
Is this expected behavior or am i doing something wrong? Is there any way to overcome this issue when using css sprites?
I do not have much experience with html and first time going to use css sprites. Please help.
Edit: also, many posts I could see in internet about cross-browser issues while zooming. Is this some point of concern even now?
If your sprite size is 200x200 px, and you want to get better resolution by zooming - make you background-size: 100px 100px;. So if you will zoom to 200% - the quality of you image will still be good. Obviously, your sprite image should be twice bigger the size you are going to use on your website. To avoid problems - do not mix % and px or any other different units in one background-size. Use only px in your case and everything will work just fine.
Summarizing. Make sprite twice bigger, set background-size twice smaller the size of sprite image. Tested it in Chrome and FF. Works fine on zooming.
If you are familiar with svg files - try to do your own vector font (for icons) using http://fontastic.me/. No scaling issues will disturb you. You can set size by font-size and make them any color by color in CSS, like a text.
I have a WordPress site, which has an issue with the logo.
If you'll view it on a desktop(not retina),
it will be blurred after load BUT after scaling-up and scaling back its appearance becomes normal.
The source image height is 100, and height is 50, so why does it gets blurred?
I believe it is the original image resolution that create this.
Optimising your picture for the actual size would solve your problem I believe or setting the custom CSS to the following (with the current image size):
.nm-header-logo img {
height: 51px;
}
When an image is bigger than what you set it for 50px the browser shrinks the images to that size. In a lot of cases the result is not good and it may even be worse in some browsers (e.g. Chrome). You end up with blurry or jagged edges. Since you still need retina support you should try using 2 images, a smaller one that has 50px height that will load for non retina and one for retina which is twice as big. You have to modify the code for that:
You can use this method here.
E.g.
<img srcset="logo-twice-as-big.jpg 2x"
src="logo-normal-size.jpg" alt="Logo">
Try adding this property to your image.
.nm-header-logo img {
image-rendering: pixelated;
}
The image-rendering property defines how the browser should render an image if it is scaled up or down from its original dimensions.
The possible values are : auto | crisp-edges | pixelated
pixelated: as the image changes size the browser will preserve its pixelated style by using nearest-neighbour scaling. This value only applies to images that are scaled up.
I can reproduce this issue in both Chrome and Firefox.
This is SVG image in question:
https://www.iconfinder.com/icons/284101/editor_hambuger_list_menu_view_icon#size=512
And this is the minimum code which reproduces the problem:
<img
style="width: 15px; vertical-align: middle;"
src="data:image/svg+xml;base64,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" /> Menu
You can play with it and see it in action at:
http://jsfiddle.net/adamovic/s3dZ2/1/
Anyone has an idea why this Scalable Vector Graphics gets resize where lines becomes unproportional and also any idea how to fix this good?
BTW, in production I'm resizing this image to 1EM, to appear next to text "Menu" but to reproduce this issue it is the simplest way.
UPDATE: Updated example from 11.5px to 15px, reproducing same issue.
In production I'm using width: 1EM; or something like that for responsive design, any idea how to responsive scale this image so that lines are proportional?
Maybe some fix like min-width and max-width could work, but I couldn't make it work ever with some mozilla image specific commands.
At 11.5 pixels in with the height of the image should be 6.3 pixels. Of those, 1.1 pixels should be the height of each black line, and 1.5 pixels the height of each white line. And on top of that the browser resizes the picture to 6 pixels height.
If the image had 1 pixels for each line (both white and black) and the size multiple of 5, it would look great.
Later edit
In the given picture a black line is 16.67% of image size(all lines reprezent 50%) and a white line is 25%. So... for a height of 8 pixels the a black line has a height of 1.3 pixels and a a white line 2 pixels. On paper the smallest image that looks good and unaltered has 2 pixels for black line and 3 for the white line, meaning an image with 12 pixels height.
Basically if one pixel has to share both white and black lines the browser will create a shade of gray that is the average of the two as it can only display one color.
EX: a pixel has to show 0.67 white(#FFFFFF or 255,255,255) and 0.33(#000000 or 0,0,0) black:
0.67*255 + 0.33*0 = 170.85 (aproximatly 171) so the color displayed is (#ABABAB or 171,171,171)
Theoretically, SVG image is infinitely scalable. In practice however, the screen has limited resolutions, so if you scale an SVG too small, it won't look very good due to pixelations.
To avoid this problem, you need to set a minimum size for the icon at the point where it still looks good. High quality small-sized vector iconsets would usually be designed to have in such a way that their major lines lie in a grid of integer proportion for many different sizes, so that they will look crisp on different sizes; some icon designers might also provide a separately-drawn raster icons for low resolutions.
Inferring from the size declaration in the SVG, the icon you linked seems to have been designed for 22x12 or multiples of it.
On small sizes, you probably should also use media-queries so that small icons are scaled in a step-ladder of sizes with sizes that are known to look good rather than strictly depending on the viewport size.
If you take the following image:
http://ecx.images-amazon.com/images/I/41uxky7oT8L._SL160_.jpg
place it in an html file with an IMG tag, then resize it to width 160 but do not set the height setting, and are on Firefox, you will see an ugly black line under the image.
For instance:
<img src="http://ecx.images-amazon.com/images/I/41uxky7oT8L._SL160_.jpg" alt="" width="160" />
or
<img src="http://ecx.images-amazon.com/images/I/41uxky7oT8L._SL160_.jpg" alt="" style="width:160px;" />
(Note I'm using FF 3.6.3 on Ubuntu Linux 8.04 LTS, if that matters.)
Note I don't want to set height because then the image would look funny when all I want to do is change the width so that fits nicely in a column of amazon products. Plus, I cannot always accurately predict the image height, and some APIs to inspect the image may slow a website down too much.
So, why do you think the black line appears, and what can I do programmatically in the HTML or CSS to prevent it? Note I've already tried setting the style of background-color for the image to #FFF and I still get this issue.
Resize the image with JavaScript as needed to prevent distortion by the browser. I do it because only Opera and Chrome "smooth resize" large images to tiny sizes.
I've read all over the Internet that I should not define fonts (or anything) with absolute pixel height/width/size and instead, use EM ... so that on higher resolution displays, my web site can scale appropriately.
However, what do I use to define IMAGE height/width ... because images won't scale well (they look pixelated)
UPDATE:
To clarify, I'm not referring to page zoom. I'm referring to how to make my web application resolution independent so that it will look correct on higher DPI displays.
I know this question is a bit old, but want to put this out there for anybody who may come along later. When talking about mobile devices which have higher pixel densities, the mobile browsers will zoom the page in by an amount to make it appear as though the web page is not very small. Devices implement this zooming as per the CSS 2.1 specification.
For example, many devices today have a 1.5x pixel density ratio compared to desktop monitors. As a result, the mobile browser will zoom websites by about 150% to compensate for the extra pixels. The new retina display has a 2x pixel density ratio... and as such the browser zooms in websites by about 200%.
Point of the matter - developers should not have to worry about different resolution devices. If you wish for your images to show up clearly on high resolution devices, you will need a higher resolution image. You generally don't have to worry about 1.5x devices as the quality difference is negligible and not worth the effort. However, the new retina display causes some really blurry images, and as a result you should use 2x the image.
So for the following image, you would want to export a 600x400px image in order for the image to show up clearly on the new retina display:
<img src="photo.jpg" style="width:300px; height:200px" />
Font sizes should be set in em (or %) because if the user changes the text size in IE (View > Text Size), text set in px (or have a fixed size somewhere up the inheritance chain) won't be resized. (Other browsers have no problem resizing text set in px.) See How to size text using ems for more on this.
Images with px dimensions are not resized when the user changes text size; images with em dimensions are resized. So if an image's size should be relative to the text size (a rare case), then use em. Otherwise px dimensions is fine.
For page zoom (where the browser makes everything larger or smaller), it doesn't matter if dimensions (text or image) are defined using em or px.
Normally, I use em for most elements and exact pixels for images. Your images will not scale with everything else when the text size is adjusted, so you need to review how the page looks at different text sizes and adapt when required, but I find this a reasonable compromise (versus scaling the images that is).
Using em when resizing the text in IE, it becomes larger than it should when made larger, and smaller than it should when made smaller.
The solution that works in all browsers, is to set a default font-size in percent for the body element:
body {font-size:100%;}
h1 {font-size:2.5em;}
h2 {font-size:1.875em;}
p {font-size:0.875em;}
http://w3schools.com/css/css_font.asp
You can find a perfect example of image styling using px with source code here: http://w3schools.com/css/css_image_gallery.asp. The images scales perfectly with the text increasing or decreasing it.
see the solution of this page
http://nickcowie.com/2005/elastic-images/
HTML
<div class="imageholder">
<img src="/images/tim_underwood_rb2.jpg" class="vertimage43 floatleft">
<img src="/images/joe_smash1v.jpg" class="vertimage43 floatright">
</div>
CSS
.widecolumn .imageholder {
width:51.5em;}
.widecolumn .vertimage43 {
height:32em;
margin:0;
padding:0;
width:24em;}
It's not really possible to make a page resolution-independent when it comes to images.
You can use SVG for images, because vector graphics truly are indepent of DPI, but this won't work well for photos.
You can use high-resolution images and display them at smaller size. This way, when sized up, they look a lot better. On some browsers, the downscaled image won't look too bad.
This is an example page, http://www.cssplay.co.uk/menu/em_images it has high-res images that are sized with ems. On Opera with page zoom, the high res images retain their clarity at higher zoom levels.
For retina devices you can also have a second image twice the size and add #2x to the file name...
so if you have a 200px x 300px image called image.jpg you just put in another one that's 400px x 600px and name it image#2x.jpg and retina devices will display that instead.