Can anyone explain how this image protection trick is done? - graphics

If you look at this image
you can see it just fine (with anti theft diagonals over it.) in a browser but trying copying it and opening it up in your favorite image editor. The image is mostly black with the lines and an almost impossible to see version of the shape in editors.
I'm guessing they messed with the png meta data that browsers don't generally read but editors do?

It's not image protection. The file contains an alpha channel. The area between the hash lines has an alpha of 0, which means transparent. Many image viewers do strange things in this situation. They may, for example, clear the background to black before drawing the image.

Related

Coloured textures for POIs

I was trying to use a coloured texture (PNG 24/RGB) for a POI (bicycle_parking) and it was not being rendered. It was added properly as a texture, it just won't be rendered on the POI.
After some testing I came to believe that POIs only accept grayscale textures that can later be filled up with a color. Is this right?
I also found out that the icon needs to be of a specific size (I got it working only at 32x32 pixels and 512x512, but the scaling did not make it look good). Is there any information regarding this?
Now I have a grayscale icon (mostly white) but the fill color does not change the white as expected. This is as far as I got..
Here's a set of icons similar to the ones I need to render into POIs
How could I achieve adding this type of icons as the texture of a POI? Workarounds/hacks are welcome as well :)
Thanks!
The texture of the Poi must have a size that is a power of 2 and goes from 32x32 up until 512x512. Also make sure that the colour code of that image is RGB anything else wont work. For the best visual result you have to create 3 sets of pngs for different screen densities, for example see heatmap_legend.png then look at heatmap_legend#2x.png and heatmap_legend#3x.png, you can find them in the "common" folder.
So turns out that the color wasn't a problem after all. It was quite tricky to get one image working, but once I had the image working, adding color to it and saving the PNG worked just fine.
The problem with the image size I experienced is still happening. You need to export it in 32x32, 64x64 or 96x96 in order to StyleEditor not to crash when opening the file.

last state Animated Gif designed for html email in Fireworks cs5 fails in some clients

This is my second question, and I’m hoping to resolve an issue that I haven’t found addressed, though I did search for an answer.
Links and screenshots to problem are below. Using Fireworks CS5, I have created an animated gif consisting of 3 states that loops 3 times. It is built on layers, with the 3 states sharing only a background border. They do not share the background (the background is grouped layer consisting of a red box with a clipping path of white, which seems to work in the first two states, but fails in the third state) itself, or any other element.
It is a tile ad for an html e-newsletter, and it works on some clients (gmail, for instance), but the final state does not render properly in other clients (mac mail, for instance). To add to the issue, the same file was rendering correctly in Mac Mail earlier. The gif works if I open it in a browser (usually), as well.
I thought that animated gifs were very stable across platforms except for problems with looping in Outlook 2007 and I've never had this issue before (granted my experience is limited). Has anyone else had this experience? Does anyone have advice on this issue?
Many thanks,
Andrew.
Link to the good. This is the animated gif file. It may not work in all browsers (I did test the file thoroughly, but the weird issue just seems completely sporadic), but renders correctly in latest Firefox for Mac OS 10.7x.
Link to the bad. The third state is see-through, the background layer is not rendering.
Turn Off the Alpha Transparency in the optimization panel. After carefully examining each state, I realized that I had Alpha Transparency turned ON in the export. Even though each state had a solid red back ground, and even though the other states correctly rendered the solid red background, the Alpha Transparency was messing up the last state of the animation. To correct it, I simply turned OFF the Alpha Transparency. I don't know why I didn't think about that as the solution before. I hope this answer helps someone!

Why does IE change the color?

I've placed an image on top of a div. I'm trying to blend the image into the div (The div is a solid color). In Google Chrome, it looks great! The colors blend perfectly. In IE 7, however, the colors show a hard line even though they should be the same color! After some examination (a print screen put into paint.net to check the actual RGB values), IE 7 is actually lightning up my image.
The blend has to look seamless. Google Chrome was fine with this thus far. Any ideas why IE 7 wont display the color right?
The two browsers are using different rendering engines. There are minor differences between them in how they render graphics, particularly jpegs.
The differences are minor but unavoidable.
Most of the time it goes unnoticed; it only makes an appearance in cases like yours when you try to position it against an element with a solid background colour that is supposed to be the same.
You may be able to resolve the issue by using a different image format. Try saving the image as a PNG. PNGs tend to be rendered more accurately between the browsers than jpegs, so that might be enough to solve your problem.
If that doesn't solve your problem, you could try using PNGs alpha transparency feature to produce an image with a fade to transparent at the edge, and then overlap the background colour behind it. This will definitely give you a smooth transition, but is a bit more technical, so harder to achieve. It will also give you problems with older versions of IE (IE6 for sure, I think you'll be okay with IE7), as they had some major bugs with PNG transparency. (If this is an issue for you, there are work-arounds for this; google IEPNGFix for more)

Pixlelated borders when i save image as GIF with Transparent In Illustrator

World Map Images in Adobe Illustrator CS5
I have an image Map in illustrator CS5 which i want to save in GIF so as to reduce its size for web use. But when i save it, the map boundaries are having some white pixels all along the map boundaries of map.
I really dont know why has happened to it, but cant save it in Png-8, png-24 formate due to size constraint.
Any meaningful answer will be highly appreciate and thanks in advance.
Is your background a non-changable color? Maybe you can save the image with the same color as a background.
The problem is gifs don't support true transparency.
If this doesn't work can you provide the image you are trying to save (gif and png, I don't have AI right now)? Maybe there will be something I can do about the size or clearing the gif's edges.
transparent GIFs don't have an 8-bit alpha channel, like PNG does: a pixel in a GIF is either there, or it's not: if it's there, you can't see through it. This often means that an edge between transparent and non-transparent areas looks blocky.
There are two ways to deal with this... either use a PNG 24 (and the Illustrator Save for Web feature will help you to make it smaller), or in Illustrator create a background color layer behind your image before you export to GIF. If this background color layer is the same as the website you put the image on, the edges will blend nicely.

alpha transparency solution in IE

I am building a website with a TON of png-24 files that have transparent background. In IE 6 they obviously aren't displayed correctly, so I need some sort of reliable, good solution that will fix the PNG problem in IE and require little work and be reliable. Any good ideas?
For IE6 transparency I follow a personal flow:
1. If there is just one or two PNG images (like a logo, or a normal image) I just use filter:
#selector {background:none; filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src='test.png', sizingMethod='crop');}
Problems: If applied to a link, it will no longer be clickable. Possibly apply to the h1#logo and have the a be transparent.
2. If I have a lot of 24-bit PNG files, or special use cases (repeating background, etc), I use DD_belatedPNG
IMPORTANT FOR IE7 + IE8: You cannot animate or combine the filter:alpha (which is used for overall opacity on an element in IE and also used by jQuery to set opacity) property with 24-bit transparent PNG images. It changes it to look like 8-bit transparency, with everything that is not 100% opaque or transparent taking on a black background.
Here are a few good png fixes for ie6:
http://labs.unitinteractive.com/unitpngfix.php
http://www.twinhelix.com/css/iepngfix/
There are a lot IE PNG fixes on the net, which basically all work with the same technique. The older Internet Explorers do not support alpha in PNGs directly, but they all have a filter that does so. So writing the following code as part of a css of an object puts the image in the src to the background of the element:
filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src='image.png');
That way, you can easily display transparency in the Internet Explorer. However it's a lot easier to just get one of the png fix scripts (in JavaScript) and include it to your page inside of conditional comments. Then the script will make all your images working automatically.
We used Dean Edwards' IE7 for this. (So named before IE7 came out.) It's been good for that kind of thing.
There are currently many options to get this working. The standard is apply a DirectX filter through CSS to change make the PNG transparent in IE6. There are even scripts that will automatically do this when the webpage loads from an IE6 or less client.
http://www.google.com/search?btnG=1&pws=0&q=transparent+png+ie6

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