Google Data Center... this is the Cloud!!!

You can see it at.... Google Official Blog

Very few people have stepped inside Google’s data centers, and for good reason: our first priority is the privacy and security of your data, and we go to great lengths to protect it, keeping our sites under close guard. While we’ve shared many of our designs and best practices, and we’ve been publishing our efficiency data since 2008, only a small set of employees have access to the server floor itself.

Today, for the first time, you can see inside our data centers and pay them a virtual visit. On Where the Internet lives, our new site featuring beautiful photographs by Connie Zhou, you’ll get a never-before-seen look at the technology, the people and the places that keep Google running.

The server floor in Council Bluffs, Iowa

Night falls over our Lenoir, North Carolina data center  

 In addition, you can now explore our Lenoir, NC data center at your own pace in Street View. Walk in the front door, head up the stairs, turn right at the ping-pong table and head down the hall to the data center floor. Or take a stroll around the exterior of the facility to see our energy-efficient cooling infrastructure. You can also watch a video tour to learn more about what you're viewing in Street View and see some of our equipment in action.


Finally, we invited author and WIRED reporter Steven Levy to talk to the architects of our infrastructure and get an unprecedented look at its inner workings. His new story is an exploration of the history and evolution of our infrastructure, with a first-time-ever report from the floor of a Google data center.

Fourteen years ago, back when Google was a student research project, Larry and Sergey powered their new search engine using a few cheap, off-the-shelf servers stacked in creative ways. We’ve grown a bit since then, and we hope you enjoy this glimpse at what we’ve built. In the coming days we’ll share a series of posts on the Google Green Blog that explore some of the photographs in more detail, so stay tuned for more!

Posted by Urs Hölzle, Senior Vice President, Technical Infrastructure

Gmail and GoogleDocs

Hello!,

We have just created some files with OpenOffice and talked about file formats. Which office package do you use...which file formats do you create?.

Siân... do you have a gmail account? Tell us about your mail.
Have you ever done a blog in blogger? Tell us.
What for do you use Internet?.

We are now learning to use GoogleDocs. With GD, you can use programs in the cloud, and also store your files (you can create and upload files). You can create labels or collections. A file can be in different labels.
An you can also share your files with everyone... or just with certain email addresses.

- Google Docs lets you create, share, and collaborate on documents online. And it just got better with rebuilt editors for documents, spreadsheets, and drawings, designed to improve collaboration, increase speed, and create richer documents.-

Unit 1 - INITIAL: starting to work!

Hello everybody!.

New course, Unit 1: we'll learn how to be in contact, how to publish in the blog, basic ICT concepts and Google Drive.

Let's start!

Just to start a class

Hello,

just to see a class!

Unit 5 - Digital Video concepts

Basic Digital Video Concepts

The following is a list of aspects of digital video that can be manipulated with standard video-editing software. It is important to be familiar with these terms so you can create video optimized for web delivery.

Movie length

It's a simple principle -- limiting the length of your video clip limits its file size. Videos longer than a minute or two may cause prohibitively long download times. If you must serve longer videos, consider one of the streaming video solutions.

Frame size

Obviously, the size of the frame has an impact on the size of the file. "Full-screen" video is 640 480 pixels. The amount of data required to deliver an image of that size would be prohibitive for most web applications. The most common frame size for web video is 160 120 pixels. Some producers go as small as 120 90 pixels. It is not recommended that you use a frame size larger than 320 240 with current technology. Actual size limits depend mostly on CPU power and bandwidth of the user's Internet link.

Frame rate

The frame rate is measured in number of frames per second (fps). Standard TV-quality video uses a frame rate of 30 frames per second to create the effect of smooth movement. For the Web, a frame rate of 15 or even 10 fps is more appropriate and still capable of producing fairly smooth video playback. For "talking head" and other low-motion subjects, even lower frame rates may be satisfactory. Commercial Internet broadcasts are routinely done as low as 0.5, 0.25, or even 0.05 frames per second (resulting in a slideshow effect rather than moving video).

Quality

Many video-editing applications allow you to set the overall quality of the video image. The degree to which the compression algorithms crunch and discard data is determined by the target quality setting. A setting of Low or Medium results in fairly high compression and is appropriate for web delivery. Frame rate and quality are often traded off in different degrees in relation to each other, depending on the application, to reduce bandwidth requirements.

Color bit depth

The size of the video is affected by the number of pixel colors in each frame. Reducing the number of colors from 24- to 8-bit color will drastically reduce the file size of your video, just as it does for still images. Of course, you also sacrifice image quality.

Data rate (bit rate)

This is the rate at which data must be transferred in order for the video to play smoothly without interruption. The data rate (also called "bit rate") for a movie is measured in kilobytes per second (K/sec or Kbps). It can be calculated by dividing the size of the file (in K) by the length of the movie (in seconds). So, for example, a highly compressed movie that is 1900K (1.9 MB) and 40 seconds long has a data rate of 47.5K/sec.
For streaming media in particular, a file's data rate is more important than its total size. This is due to the fact that the total bandwidth available for delivery may be severely limited, particularly over a dial-up connection. For example, even an ISDN line at 128 Kbps offers a capacity to deliver only 16K of data per second. 



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Compression

Digital video wouldn't be possible without methods for compressing the vast amounts of data necessary to describe sound and frame images. Video files can be compressed in a number of ways. This section looks at a variety of compression schemes and introduces the methods they use for achieving compression rates. Understanding your options can help you make better decisions for optimizing your video files.

25.2.1. Lossless Versus Lossy Compression

Compression can be "lossless," which means no information is lost and the final file is identical to the original.
Most compression schemes use forms of lossy compression. Lossy compression sacrifices some data from the file to achieve much higher compression rates. Lossy compression schemes, such as MPEG, use complicated algorithms that toss out data for sound and image detail that is not discernible to the human ear or eye. The decompressed file is extremely similar in character to the original, yet is not identical. This is similar to the way JPEG handles still images.

25.2.2. Spatial Versus Temporal Compression

Spatial (or intraframe) compression takes place on each individual frame of the video, compressing the pixel information as though it were a still image.
Temporal (or interframe) compression happens over a series of frames and takes advantage of areas of the image that remain unchanged from frame to frame, throwing out data for repeated pixels.
Temporal compression relies on the placement of key frames interspersed throughout the frames sequence. The key frames are used as masters against which the following frames (called delta frames) are compared. It is recommended that a key frame be placed once every second; therefore, if you have a frame rate of 15 fps, set your key frame rate once every 15 frames.
Videos without a lot of motion, such as talking head clips, take the best advantage of temporal compression. Videos with pans and other motion are compressed less efficiently.

25.2.3. Video Codecs

There are a number of codecs (compression/decompression algorithms) that can be used to compress video files for the Web. Many of these codecs can be applied to several different file formats (discussed in the next section of this chapter).
Video-editing software packages often offer a long list of codecs in their compressor list options. Here we focus on just those that are relevant to video intended for web delivery. 



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Video File Formats

As with audio, in the early days of the Web, adding video to a web page meant using one of the currently available video formats (such as QuickTime or AVI) and linking it to a page for download. The evolution of streaming media has changed that, and now adding video content like movie trailers, news broadcasts, even live programming to a web site is much more practical and widespread.
This section looks at the video formats that are most common for web delivery.

25.3.1. QuickTime Movie (.mov)

QuickTime is a highly versatile and well-supported media format. While originally developed as a video format, it has evolved into a container format capable of storing all sorts of media (still images, audio, video, Flash, and SMIL presentations). For the complete list of file formats supported by QuickTime, see http://www.apple.com/quicktime/specifications.html.
QuickTime, a system extension that makes it possible to view audio/video information on a computer, was introduced by Apple Computer in 1991. Although developed for the Macintosh, it is also supported on PCs via QuickTime for Windows. QuickTime has grown to be the industry standard for multimedia development, and most hardware and software offer QuickTime support. Both Netscape Navigator 3.0+ and Internet Explorer 3.0+ come with QuickTime plug-in players, so the majority of web readers are able to view QuickTime movies right in the browser.

25.3.1.1. Streaming

QuickTime movies can be streamed using a number of streaming server packages, including Apple's QuickTime Server for Mac OS X or its open source Darwin Streaming Server for Unix. To give the illusion of streaming from an HTTP server (pseudo-streaming), create FastStart Quicktime movies, which begin playing right away and continue playing as the file downloads.

25.3.1.2. Creating QuickTime movies

You can take care of rudimentary video editing, such as deleting and rearranging, right in Apple's free QuickTime Player. The QuickTime Pro version ($29.95) offers more features and is sufficient for most basic tasks. For advanced video editing, use a professional video editing tool such as Adobe Premier or AfterEffects (most video editors support QuickTime). You may also use a file converter, such as Cleaner from Terran Interactive (http://www.terran.com) to convert existing files to QuickTime format.
Other video editing applications for the Mac include iMovie (which ships free on newer Macintoshes) and Final Cut Pro, a more professional video editing program.
An important step to remember when saving a movie is to make it self-contained. This process resolves all data references and prepares the file to go out on the Internet on its own. You will also be asked to pick a codec (QuickTime supports several). Cinepak is a good general purpose codec; Sorenson is more efficient but not as well supported.

25.3.1.3. Reference movies

Another interesting feature of Version 2.0 and higher of the QuickTime plug-in is its support for reference movies. Reference movies are used as pointers to alternate versions (or "tracks") of a movie, each optimized for a different connection speed. When a user downloads the reference movie, the plug-in ensures that the best track for the current connection speed is played.
You could also save a version of your movie that doesn't use the Sorenson codec in the reference file. This movie will play for users who don't have the latest plug-in version, ensuring backwards compatibility.

Unit 5 - Digital Video: create your films!

Hello,

Here yo have a video...on how to make a video with Pitivi, a free software you can use in your Lliurex or Ubuntu OS, or download it to use it on Windows OS.

Have a look!. Try to find the new vocabulary about video and write it down on a new post in your ICT blog.

The Ubuntu Tutorial...




Another one...

Unit 4 - Digital Image: beginning with GIMP

Hello again,

We are now learning how to work with Gimp.

Read this text...and then create a new post at your blog. See you on Monday.

source: http://www.gimptalk.com/index.php?/topic/34102-beginning-with-gimp-starting-tutorial-for-new-users/

Beginning with GIMP -- Starting Tutorial for new users

So you have just started with GIMP, and now you are completely lost as to what to do next? There are windows and buttons everywhere and nothing makes sense? If so, this is the tutorial for you. 

The idea is for you to get going with a quick run-through of setting up a vanilla install of GIMP, followed by you doing your first little image in the program.

Installing GIMP

GIMP exists for many different computing platforms, including Linux, Windows and Mac. The current stable versions are 2.6.x and this tutorial will not be fully correct if you are using an older version than 2.6.0. Once GIMP is installed, you can see what version you have in the menu Help->About (to find the menu see below).

• Linux downloads can be found here: http://www.gimp.org/downloads/
• Windows installers here: http://gimp-win.sourceforge.net/
  Photocomix has made a convenient Python-support install package [here], which adds support for the many filters and additions written in Python. Read the install instructions before asking about it. 
• Mac downloads here: http://www.gimp.org/macintosh/

First of all it should be remembered that GIMP's interface is extremely flexible. You can add and remove windows from it as you like.

To the top left you have the Tool box. This contains the most commonly used functions of the program, quite literally the artist's box of utilities. These tools are in fact so often used that almost all of them also have default keyboard shortcuts for even faster access. You are wise to learn most of these by heart if you want to be effective. 

Attached to the bottom of the tool box is the Tool options dock. This shows the settings for each tool and thus changes depending on which tool is currently active. In the image we see the tool options for the paintbrush tool. 

To the far right we have a dock that contains several things in one. What we see at the moment is the empty Layer list window. As we start creating a new image, this list will start to fill with layers.

You also see that there are a bunch of tabs in the upper part of this window, clicking these will bring forth other functionality.

Below the layer list, another dock is attached, containing the list of brushes usable by GIMP. Brushes are, quite like their real-world counterpart, things you use to mark down things on the canvas. They can be used to emulate actual paint brushes, but also be used as "stamps" for creating nice effects, as well as be animated. 

There are two more tabs in this dock, these show lists of patterns and gradients respectively (click them to see). Patterns create seamless mosaics of structure (you could for example use a pattern to paint a checker board). Gradients produce transitions between colours in various ways. All brushes, patterns and gradients can be modified and customized by the user. **this in gray is not so important**

In the center you find the main dock window (Formally this is actually called the Empty Image window). This is the main work area. It starts out small, but it will resize to hold your image when you create or load one. It also is also here you find the menu. To close GIMP you can either close this window or close the tool box (or use the menu File->Quit).

source: http://docs.gimp.org/en/gimp-first-steps.html

This section provides a brief introduction to the basic concepts and terminology used in GIMP. The concepts presented here are explained in much greater depth elsewhere.

Images

Images are the basic entities used by GIMP. Roughly speaking, an “image” corresponds to a single file, such as a TIFF or JPEG file. You can also think of an image as corresponding to a single display window.

A GIMP image may be quite a complicated thing. Instead of thinking of it as a sheet of paper with a picture on it, think of it as more like a stack of sheets, called “layers”. In addition to a stack of layers, a GIMP image may contain a selection mask, a set of channels, and a set of paths.

In GIMP, it is possible to have many images open at the same time.

Layers

If a simple image can be compared to a single sheet of paper, an image with layers is likened to a sheaf of transparent papers stacked one on top of the other. You can draw on each paper, but still see the content of the other sheets through the transparent areas. You can also move one sheet in relation to the others. Sophisticated GIMP users often deal with images containing many layers, even dozens of them. Layers need not be opaque, and they need not cover the entire extent of an image, so when you look at an image's display, you may see more than just the top layer: you may see elements of many layers.

Resolution

Digital images comprise of a grid of square elements of varying colors, called pixels. Each image has a pixel size, such as 900 pixels wide by 600 pixels high. But pixels don't have a set size in physical space. To set up an image for printing, we use a value called resolution, defined as the ratio between an image's size in pixels and its physical size (usually in inches) when it is printed on paper. Most file formats (but not all) can save this value, which is expressed as ppi — pixels per inch. When printing a file, the resolution value determines the size the image will have on paper, and as a result, the physical size of the pixels. The same 900x600 pixel image may be printed as a small 3x2" card with barely noticeable pixels — or as a large poster with large, chunky pixels. Images imported from cameras and mobile devices tend to have a resolution value attached to the file. The value is usually 72 or 96ppi. It is important to realize that this value is arbitrary and was chosen for historic reasons. You can always change the resolution value inside GIMP — this has no effect on the actual image pixels. Furthermore, for uses such as displaying images on line, on mobile devices, television or video games — in short, any use that is not print — the resolution value is meaningless and is ignored, and instead the image is usually displayed so that each image pixel conforms to one screen pixel.

Selections

Often when modify an image, you only want a part of the image to be affected. The “selection” mechanism makes this possible. Each image has its own selection, which you normally see as a moving dashed line separating the selected parts from the unselected parts (the so-called “marching ants” ).

A large component of learning how to use GIMP effectively is acquiring the art of making good selections—selections that contain exactly what you need and nothing more. Because selection-handling is so centrally important, GIMP provides many tools for doing it: an assortment of selection-making tools, a menu of selection operations, and the ability to switch to Quick Mask mode, in which you can treat the selection channel as though it were a color channel, thereby “painting the selection”.

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Now go to your Blog and answer these questions, in a short way:


1-What's Gimp?
2-How can you get Gimp and use it in your computer, at home?
3-Make a list of windows in Gimp.
4-Make a list of words related with digital image.
5-Make a list of words related with using Gimp.
6-Why do we use layers?
7-Is it important to make a selection, when using Gimp?
8-What can you find out in Internet about me? (gimp logo)

Unit 2 - Operating Systems

Hello again!!

We come back for a week to Unit 2. As you can read a wikipedia article:

"An operating system (OS) is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system. A user cannot run an application program on the computer without an operating system, unless the application program is self booting"




I also liked this web where you can read:

"When you turn on your computer, it's nice to think that you're in control. There's the trusty computer mouse, which you can move anywhere on the screen, summoning up your music library or Internet browser at the slightest whim. Although it's easy to feel like a director in front of your desktop or laptop, there's a lot going on inside, and the real man behind the curtain handling the necessary tasks is the operating system.

Most desktop or laptop PCs come pre-loaded with Microsoft Windows. Macintosh computers come pre-loaded with Mac OS X. Many corporate servers use the Linux or UNIX operating systems. The operating system (OS) is the first thing loaded onto the computer -- without the operating system, a computer is useless.

More recently, operating systems have started to pop up in smaller computers as well. If you like to tinker with electronic devices, you're probably pleased that operating systems can now be found on many of the devices we use every day, from cell phones to wireless access points. The computers used in these little devices have gotten so powerful that they can now actually run an operating system and applications. The computer in a typical modern cell phone is now more powerful than a desktop computer from 20 years ago, so this progression makes sense and is a natural development".

Just a joke!!!

I also found interesting the list of functions this web lists:

"An operating system performs these services for applications:

• In a multitasking operating system where multiple programs can be running at the same time, the operating system determines which applications should run in what order and how much time should be allowed for each application before giving another application a turn.
• It manages the sharing of internal memory among multiple applications.
• It handles input and output to and from attached hardware devices, such as hard disks, printers, and dial-up ports.
• It sends messages to each application or interactive user (or to a system operator) about the status of operation and any errors that may have occurred.
• It can offload the management of what are called batch jobs (for example, printing) so that the initiating application is freed from this work.
• On computers that can provide parallel processing, an operating system can manage how to divide the program so that it runs on more than one processor at a time."

Now, go to your blog and write down:

1. What an Operating System is.
2. Which Operating Systems are most used.
3. Make a list of words related with Operating systems and ICT you can find in the text you read above.

Come back to classes!!!

Hello!...