Friday, July 29, 2016

Movies How its Done?

with evaluation of computers, the movies that run on theater came to them as that can be stored in a hard disk. Hows this possible? What makes a movie run on computer. The  truth is movies run as same way as theater. theaters use sequence of images to run one after another so it will give an illusion as continuous thing. See our eye can only process data coming from 1/10 of a second, so anything less you will not find as 2 but a continuation of first i.e. if some pictures changes in 1/5 of a second you will see that it changes, but if it change in 1/24 the of a second you will see as continue animation. So we can trick the eye to believe it is real this is because fastest speed of our neuron take 1/10 of time to communicate so to send an image from eye to brain and process it will take more than 1/10 seconds of time and any thing coming between this to eye, we will not see and when second image comes and if it is moved slightly the brain will fill the gaps and let us see as it is moving or animated.

so if we show our brain image in every 1/24 th of a second we will see it as animated. So in computer where is the images comes from. As you know we can store images as series of pixels and can have array of these series of pixels stack one after the other. giving us a series of images one after the other. and player is able to call them in a given rate and draw them to display like 1/24 th of a second so we will see a series of images in front of us and our brain will think it is continues and let us see the movie.

it will take a lot of space to keep a movie in row form, since it is a series of image so compression is done. some of the images are removed and images also get compressed like you know in jpg or gif so it will reduce the size of the movie dramatically. With this quality also degraded but we get to see a nice movie.

for instance a movie on 1 hour will take 60X60 seconds and that is 60X60X24 frames. If it runs 24 images for seconds (which is called frame rate) and if the size of the image, that is width and height of the movie is 800X600 i.e. 800 pixels wide and 600 pixels in hight, then it will take 800X600X3 number of bytes since each pixel take 3 bytes to represent the colors RGB one for red one for Green one for Blue so to store whole movie it will take 60X60X24X800X600X3 bytes i.e. 124416000000 bytes or 115GB which is not the best to store in hard disks so it is compressed to something like 1.5 GB to save space. by methods like MPEG4

Thursday, July 28, 2016

Bridge network Server 2012 r2

Bridge Network Windows 2012

How to Bridge and configer

How to bridge windows 2008 Server

Enable and Configure NAT

Applies To: Windows Server 2008 R2
Network address translation (NAT) allows you to share a connection to the public Internet through a single interface with a single public IP address. The computers on the private network use private, non-routable addresses. NAT maps the private addresses to the public address.
Membership in the local Administrators group, or equivalent, is the minimum required to complete this procedure.
To enable network address translation addressing
  1. In the RRAS MMC snap-in, expand Your Server Name. If you are using Server Manager, expand Routing and Remote Access.
  2. Expand IPv4, right-click NAT, and then click Properties.
  3. If you do not have a DHCP server on the private network, then you can use the RRAS server to respond to DHCP address requests. To do this, on the Address Assignmenttab, select the Automatically assign IP addresses by using the DHCP allocator check box.
  4. To allocate addresses to clients on the private network by acting as a DHCP server, in IP address and Mask, configure a subnet address from which the addresses are assigned. For example, if you enter and a subnet mask of, then the RRAS server responds to DHCP requests with address assignments from through
  5. (Optional) To exclude addresses in the configured network range from being assigned to DHCP clients on the private network, click Exclude, click Add, and then configure the addresses.
  6. To add the public interface to the NAT configuration, right-click NAT, and then click New Interface. Select the interface connected to the public network, and then clickOK.
  7. On the NAT tab, click Public interface connected to the Internet and Enable NAT on this interface, and then click OK.
  8. If you want to add additional public addresses assigned to this interface or configure service and port mappings to computers on the private network, see IPv4 - NAT - Interface - Properties Page.
  9. To add the private interface to the NAT configuration, right-click NAT, and then click New Interface. Select the interface connected to the private network, and then clickOK.
  10. On the NAT tab, click Private interface connected to private network, and then click OK.

Additional references

Monday, July 25, 2016

Logical Thinking for Programming

Monday, July 4, 2016

Operating system

Early days when computer emerge there was programmers who write software to it. most of them were in low level languages like machine language and they were machine specific i.e. each machines software were written to it separately. Every machine use different sets of hardware and they have to handle differently so single program could not work on every machine programmers have to be written each machine separately.

These programs consist how to handle details like hardware how to send your report to printer i.e. instruction on printer how to print and sound instruction to play sound and instruction on display so they can be displayed correctly multi-tasking is a dream  they never even thought of and computers are assign single task. With the change of the hardware the software have to be change to adapt the needs of it.
Then people began to develop common platform to a compute that will manage hardware (takes care of how to handle and send instructions) and also resource management which make image of operating systems. The other software could be run on these systems depending on them so they need not to worry about the hardware or resource management tie OS did it for them. But still the OS depend on hardware and each machine have to be coded OS separately

With this things like DOS (Disk Operating system emerge) and a smart guy call bill gate had the chance to get hold of one of this he buy the system with the cording from the developer and did something miraculous, he separate the operation of hardware form the operating system so you have need not to code entire OS but the parts specifically handle that hardware which you may know now as drivers with this OS could run on multiple computers with minimum change OS are built to multi task, that is more than one process could run on single machine this is achieved by dividing time across different processes a few millisecond on process 1 and then few on process 2 then again few on 1 so on. It also handle resource management i.e. how they are shared among processes and also have mechanisms like deadlocks prevention that handle the conflicts of the resource with process. There is file manager that manage files you do not need to access hard disk directly OS do it for you so you only have to tell OS what you have to do (not how you need to do it) and OS will do it for you.

With the CLI (Command line Interface OS) we have come very far and now we have GUI(Graphical User Interface) Operating systems and many more facilities that you ever need.

for more info