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So I'm doing a pre-study on how to implement a responsive design to an existing site with a lot of images. These images would be nice if we could serve differently to the visitor according to device size, pixel ratio and/or bandwidth.
The site is using Akamai as a CDN so we must have a solution that uses different URLs for different image sizes. Doing this by Javascript is fine, we require it anyway.
I was looking at CSS-tricks spreadsheet (http://css-tricks.com/which-responsive-images-solution-should-you-use/) and specifically Foresight.js (https://github.com/adamdbradley/foresight.js) seemed to be the right stuff for us.
Basicly the markup would look something like this:
<img data-src="/images/imagefile.jpg" data-width="320" data-height="240" class="fs-img">
<noscript>
<img src="/images/imagefile.jpg">
</noscript>
But then I noticed that Google will ignore any fallback images placed within tags. This could be devastating to our SEO since the images from the press room are essential to be indexed by Google et al.
So my question is, how do you serve SEO friendly-enough images responsively? Is removing the src-attribute killing SEO? There will still be all the other attributes, the alt-one most important I guess.
yea, image alt tag is very important from search engine optimization point of view. Here there is no harm to resize the image by considering devices or element. Make sure you use meaningful image name to get them up in image search result of Google.
Interesting...
I don't really feel that you =need to "alt" tag all of the copies. From SEO point of view this is both redundant and somewhat spammy (imagine Google's response to a website in which each URL holds 5 [or more] different sized version of the same image, all with the same exact alt tags... )
Allowing Goolge to Recognize tags of the "default size" image should be enough for your SEO purposes.
Another workaround I can think of is to always have live links to all the different sizes (while presenting only one personalized version)
I`m not sure if its feasible, but you don't have to many version or want to present a few selected ones, this will do.
This will not solve the alt tag issue, but at least they all be crawled and indexed separately.
Also, alt tag is really over-rated. Speaking from almost 10 years of experience I can say that is's effect is marginal, at best. Especially if you link to the image includes the relevant KW.
If still worried, you can link to a different HTML page, containing said image and alt tag it there but it sound like too much trouble to me...
Hey guys I was looking for different approaches/algorithms for placing textual/non-textual content in a book layout having 2 sides. So essentially it should look like a user is reading a book & content placed in a 2 page layout.
If you guys have any directives or suggestions on how to go about doing this. Way to decide how many content items can fit into 2 pages, no overflow. Suppose a page is 425 px BY 600 px & we have 2 such pages fit side by side (dimensions are flexible).
Any pointers appreciated?
P.S. I know this is not a pure programming question per se but more of an algorithmic question. If so, please direct me where this question can be best asked.
EDIT 1
I want to use this algorithm in a website application & not in a standalone app, so please consider that.
EDIT 2
I would like to mention that the order of the content items is pre-decided.
If your goal is to display data in a book like format, then the easiest method would be to reuse an already existing toolkit for doing text layout. I think the best tool for this purpose would be LaTeX, which is an evolution of the original digital typesetting program.
In order to use it you will have to convert your data into the LaTeX format, which is relatively painless (I have done it several times with several types of data). In this document you can specify that you want a book format, how large the pages are, and much more. You can then render the text to pdf/ps and then display the two pages of a "book" side by side.
If what you are looking for is the actual algorithms to do it yourself, you might search around the TeX/LaTeX community for information.
I'm building an art gallery website that updates its images via AJAX, for those who have javascript enabled, rather than request multiple page loads. I assume this will appear as though my site has a high bounce percentage. I understand that search engines will not be able to index dynamic content, but will such a misinterpreted bounce rate hurt my search engine ratings, even if I have many return visitors?
Short answer, no.
Bounce rate is (if even relevant here) is the least of your problems. Worry more about the content on the page. The search engines are much better at reading dynamic content than they used to be.
If your site is 100% dynamic ajax... you might have problems. IF it's just a gallery, you'll be fine IMO. Use nice titles on pages, text on pages, alt tags etc... give the spiders lots to read.
it actually may have good bounce rate via ajax which do not normally counted by normal anlaytics ( google or whatever) systems. bounce rate is normally indicator of user activity on your site and does not depend on how much time the url changed.
I use GWT on my penwag.com website, and for some time used the approach where it was nearly 100% AJAX. I did a revamp not too long ago (see http://penwag.blogspot.com/2010/04/april-penwag-update.html) basically to change who's in the driver's seat. Now, The basic navigation is controlled by HTML, there's a lot more HTML content than there used to be. This helps in a number of ways. First, search engines have more to work with. Second, the navigation is simpler. Third, separation of concerns is easier to achieve, since each page is its own module. Fourth, integration with third-party tools is more seamless. Things that specifically affected penwag.com were Google Ads integration and Google Friend Connect integration. This is probably true of most gadgets out there: they're designed to be embedded in HTML, and embedding them into a GWT component is harder.
Some of what I said here is specific to GWT, but a lot of it is true whatever AJAX framework you're using.
I have an idea to implement a deep zoom type interface hosted in a browser for sports training data (speed, distance, heart rate etc.) However, rather than images I actually want to zoom into a hierarchy of information. For example, the initial display would contain a grid of years - hover over 2008, for example, and spin the mouse wheel (or click) will zoom into that year but during the zoom I want 2008 to fade out and be replaced with a calendar of months. Again zoom into a month and the months are replaced with the months calendar, zoom into a day and you finally see a chart with the training data plotted on it. All the time only dates with actual data would be highlighted in some fashion.
My question is whether this would even be possible and whether anyone has seen examples of this already. I'm imagining that most of the time the next level of information could be cached in the browser (in fact, because this is calendar-based, I can calculate most of that and cache the dates to be highlighted.) I could also zoom into an empty chart whilst an Ajax thread is fetching the data to display.
I've never tried anything like this before and I'm especially interested in whether DHTML would be capable of this sort of zoom (I suspect not and I would have to resort to Silverlight) and whether the Ajax execution would be uninterrupted whilst the browser rendering thread is kept busy zooming.
For Deep Zoom on images in JavaScript/Ajax there's the excellent Seadragon Ajax library by Microsoft Live Labs.
If you're looking into smooth and interactive zooming on content besides images such as text, video & vectors, have a look at the open source OpenZoom SDK I've developed over the last couple of months.
You probably could not achieve very smooth zooming with an javascript/ajax type interface, but a zoom interface would be possible. The pragmatic ajax book has a great chapter on implementing a Google maps clone. Theres no need for the technique to be restricted to zooming in and out of tiled images. The image elements can just as easily be any HTML you want. A fade effect could be applied to the zoom operation so when you move up and down a layer you get something similar to what you described. I recommend grabbing the book (Its a pragmatic programmers book, so theres a cheap and immediately downloadable PDF version available. Read the chapter, think about the techniques and then see if you think its practical for your vision. good luck.
Seadragon Ajax continues to evolve and is now OpenSeadragon:
http://openseadragon.github.io/
I've also been keeping a list of various zooming technologies, many of which use JavaScript:
https://github.com/iangilman/zooming
I don't believe ajax or dhtml are good solutions for what you are trying to achieve. I think flash/flex or silverlight may be the best option.
Check out the "scale" effect in jQuery. Here's a link. I haven't used it myself, but it might be able to do what you want. You'd have to swap out some content for different content at the right point, or your html would get too big.
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What is the name of the technology behind Google Maps which allows the server to send only the part of the map requested from the user to enhance the performance, and is there any library to handle this?
The technology could generically be described as a map server. The map server generates a map for the requested location from a large set of pre-generated map tile images covering the entire planet. The map server may overlay data from other databases on top of this. The combination of a map viewer client and geographical database is traditionally called a Geographical Information System (GIS).
Anyone can write web applications that embed Google maps using the Google Maps API.There is also a fine open source map server (called MapServer) should you wish to deploy your own map server.
As stated, Google generated all of these 256x256 tiles and is just serving the relevant tiles. From your comments it seems that you are looking for something to generate these tiles for you. Several people have written code to chop an image into tiles - for instance http://crazedmonkey.com/blog/googletilecutter or http://www.klokan.cz/projects/gdal2tiles/ both seem to be able to do what your looking for.
If you look at the link for a google maps page it will look like this:
http://maps.google.com/maps?f=q&hl=en&sll=37.0625,-95.677068&sspn=53.345014,88.769531&ie=UTF8&ll=41.226264,-81.454246&spn=0.012507,0.021672&z=16
The javascript code on the page and the server code use the numbers in the link to determine the location of the map you are viewing, the zoom level, and the size of your viewing window to determine the tiles to send to your browser.
There are commercial libraries that can provide the mapping data as well as tools to display and navigate the data. One I've seen used before is Geomicro
This is something that you can try out yourself with OpenSource,
http://www.geoserver.org
http://www.openlayers.org
and
last but not least
http://geowebcache.org/
You should be able to setup a minimal environment that does something similar to maps.google in a couple of hours.
You can also use the Google Maps API with your own images. Of course, they don't need to be a map; they can be any images. This will allow the user to drag and zoom, like in Google maps.
Here's a nice rundown of an open source stack for generating Web-based maps from one of the founders of EveryBlock.com: http://www.alistapart.com/articles/takecontrolofyourmaps
The generic name for the underlying discipline is GIS.
Are you asking for more details out of general curiosity, or do you have a specific technical need for a project?
Google gets high definition satellite shots from services that sell these images, they then store and crop this images and serve only those that are required when you look at a certain point. That is, have you noticed when you zoom-in and out that you get to see squared tiles appearing? those are the ones Google Server is serving you.
You also have to consider how they handle the load with the Google File System and MapReduce
It's just a huge image consisting of square chunks that are downloaded indepedently (using AJAX and so on). I believe it's done by some kind of internal Google libraries (could be also GWT).
More on this topic:
http://blog.grimpoteuthis.org/2005/02/mapping-google.html
Google Maps and Google Earth use something known as KML, or "Keyhole Markup Language", which is a special variant of XML. It's named in tribute to the first geo-tracking satellites. You can store information on a location in Google Earth (and it will eventuall trickle down to Google Maps) by using this markup to geocode its specific latitude and longitude coordinates. You can even include altitude.
Not to answer the question, just broader the information. Microsoft has something called "Deep zoom" for Silverlight that makes it easy to do that kind of effect.
Its a free composer where you tile upp your pictures (or one big picture) and do some other settings, then it breaks it down to a lots of smaller pictures in subfolders, one folder for each zoom-level. And then creates a page that can consume those in a smooth way.
A good blog entry about it:
http://weblogs.asp.net/jgalloway/archive/2008/03/21/why-silverlight-2-deep-zoom-really-is-something-new.aspx
I'm working on a cross browser viewer for very large historic plans and scetches. A good help for the first steps (an old blog) I found at http://www.cadmaps.com/gisblog/?p=7
to understand image pyramids (that's what Google Maps works with).
With a 'tiler' I produce a lot of images like testImage_0001111100.png. 0001111100 is i.e. 5th zoom level and x / y position in the image pyramid.
Most of calculation (neighbor images, image stack up and down) is done serverside by php called by ajax requests.
I'm struggling in the moment with (not insolvable) problems in smooth shifting and zooming. That's my problem - but read the article.
AJAX allows you to update part of the page from the javascript. Basically the javascript makes a request back to the webserver and replaces part of the existing page with the result.
JQuery is one library that makes this easier. I don't know what google uses.