Computer

JPEG Isn’t a file format. Image Analyst Mike Pound explains why not in our first in a series about how JPEG works. Colourspaces: https://youtu.be/LFXN9PiOGtY Elegant Compression (The LZ Method): https://youtu.be/goOa3DGezUA Capturing Digital Images (The Bayer Filter): https://youtu.be/LWxu4rkZBLw Discrete Cosine Transform: https://youtu.be/Q2aEzeMDHMA http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer
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Surely decimal numbers are easier to understand than binary? So why don’t computers use them? Professor Brailsford explains the relationships between binary, power and simplicity. EXTRA BITS: https://youtu.be/NlWuTYhF8KM Colossus & Bletchley Park: https://youtu.be/9HH-asvLAj4 Inside a Data Centre: https://youtu.be/fd3kSdu4W7c Steve Furber on ARM: https://youtu.be/1jOJl8gRPyQ Fishy Codes – Bletchley’s Other Secret: https://youtu.be/Ou_9ntYRzzw http://www.facebook.com/computerphile Tweets by computer_phile This
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The story of recursion continues as Professor Brailsford explains one of the most difficult programs to compute: Ackermann’s function. Professor Brailsford’s programs: http://bit.ly/1nhKtW4 Follow Up Film from the Prof in response to this film: https://www.youtube.com/watch?v=uNACwX-O5lk What on Earth is Recursion?: http://youtu.be/Mv9NEXX1VHc Fibonacci Programming: http://youtu.be/7t_pTlH9HwA Heartbleed, Running the Code: http://youtu.be/1dOCHwf8zVQ VR Series: COMING SOON! Please note,
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Commonly used grep was written overnight, but why and how did it get its name? Professor Brian Kernighan explains. EXTRA BITS: https://youtu.be/bSaBe6WiC2s Inside an ALT Coin Mining Operation: COMING SOON Unix Pipeline: https://youtu.be/bKzonnwoR2I https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile
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Colossus was one of the very first electronic, special purpose, computers and it was created almost two years earlier than the better known ENIAC. We visit Bletchley Park, home of the code breakers, and TNMoC, The National Museum of Computing. Professor Brailsford shows us the Colossus replica. The Most Difficult Program to Compute?: https://youtu.be/i7sm9dzFtEI Computer
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How do digital cameras turn light into the data that computers can handle? In this second part of our computer vision series, Image Analyst Mike Pound explains the Bayer Filter. Professor Steve Furber on the BBC Micro: https://youtu.be/y4WG549i3YY 2D Images: http://youtu.be/06OHflWNCOE Universe of Triangles: http://youtu.be/KdyvizaygyY?list=PLzH6n4zXuckrPkEUK5iMQrQyvj9Z6WCrm Pushing the Atari Limits: http://youtu.be/3OdtfsXOkEY http://www.facebook.com/computerphile Tweets by computer_phile This
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Image filters make most people think of Instagram or Camera Phone apps, but what’s really going on at pixel level? Image Analyst Dr Mike Pound explains some of the most common filters. Secrets Hidden in Images (Steganography): https://youtu.be/TWEXCYQKyDc JPEG ‘files’ & Colour: https://youtu.be/n_uNPbdenRs The Dress: https://youtu.be/Tw0PlGpaqy4 The VR Cave: https://youtu.be/STMcWUtQr1Y JPEG Discrete Cosine Transform (DCT):
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Secure Hashing Algorithm (SHA1) explained. Dr Mike Pound explains how files are used to generate seemingly random hash strings. EXTRA BITS: https://youtu.be/f8ZP_1K2Y-U Tom Scott on Hash Algorithms: https://youtu.be/b4b8ktEV4Bg http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: http://bit.ly/nottscomputer Computerphile is a sister project to
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Machine Learning where you put in a fraction of the effort? What’s not to like? – Dr Michel Valstar explains Active & Cooperative Learning. https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: https://bit.ly/nottscomputer Computerphile is a sister project to Brady Haran’s Numberphile. More
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When a Bitcoin Miner Mines, what is happening? Dr Mike Pound exposes the process.. note: at 3:39 Mike mentions a Bitcoin is mined every ten minutes when it is actually a block that is mined every ten minutes, at time of recording a successful block generates 12.5 new Bitcoins. Password Cracking: https://youtu.be/7U-RbOKanYs Onion Routing (TOR):
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Should Apple unlock a terrorists iPhone for the FBI? Professor Ross Anderson explains how this is a “Pandora’s Box” situation. Buffer Overflow Attacks: https://youtu.be/1S0aBV-Waeo $5 Computer: https://youtu.be/WR0ghM3U0M4 AI Safety: https://youtu.be/IB1OvoCNnWY EXTRA BITS: https://youtu.be/6iGxNku7ilw http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: http://bit.ly/nottscomputer Computerphile
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Before laser-printers, high quality print-outs were the domain of typesetters, expensive and tightly controlled. In 1979 a Bell Labs team reverse engineered one in their summer vacation. Professor Brailsford has the details. EXTRA BITS – More on Printing and Typesetting History: https://www.youtube.com/watch?v=HdModNEK_1U Mainframes and the Unix Revolution: http://youtu.be/-rPPqm44xLs To find out how the 1980 Bell
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The back door that may not be a back door… The suspicion about Dual_EC_DRBG – The Dual Elliptic Curve Deterministic Random Bit Generator – with Dr Mike Pound. EXTRA BITS: https://youtu.be/XEmoD06_mZ0 Nothing up my sleeve Numbers: https://youtu.be/oJWwaQm-Exs Elliptic Curves: https://youtu.be/NF1pwjL9-DE https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science
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Just what is functional programming? We asked a member of the team that created Haskell: John Hughes, Professor of Computer Science at Chalmers University of Technology in Gothenburg. http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: http://bit.ly/nottscomputer Computerphile is a sister project to
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Cookies are controversial and new laws governing them have been introduced in Europe. Extra footage: http://youtu.be/_d0G6FZ_kR4 Featuring Tom Rodden from the University of Nottingham’s Department of Computer Science. http://bit.ly/nottscomputer Follow Computerphile… http://www.facebook.com/computerphile Tweets by computer_phile Video by Sean Riley. Computerphile is a sister project to Brady Haran’s Numberphile. See the full list of Brady’s video
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Correction : as oodles of commenters have pointed out, the clock face should go from 0 to n-1. Also, worth reminding people that Mike has simplified the notation in this video (as he mentions). Mike explains the mathematics behind one of the most important pieces of computer security. (Simplified version with colour mixing analogy linked
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Hitler’s High Command didn’t use Enigma, they used a faster system called Lorenz, but when Allied forces first encountered it, they had no idea what it was and code-named it ‘Tunny’ (Tuna). Professor Brailsford explains why this relates to the early days of Computer Science Next Video in this series: https://youtu.be/yxx3Bkmv3ck The Professor’s Notes: Undulator
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Audible free book: http://www.audible.com/computerphile DoS or Denial of Service Attacks are one thing, but Amplified Denial of Service Attacks could threaten the internet itself. Tom Scott explains what they are. More from Tom Scott: http://www.youtube.com/user/enyay and https://twitter.com/tomscott http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computerphile is a sister project
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Making yourself the all-powerful “Root” super-user on a computer using a buffer overflow attack. Assistant Professor Dr Mike Pound details how it’s done. The Stack: https://youtu.be/7ha78yWRDlE Botnets: https://youtu.be/UVFmC178_Vs The Golden Key: iPhone Encryption: https://youtu.be/6RNKtwAGvqc 3D Stereo Vision: https://youtu.be/O7B2vCsTpC0 Brain Scanner: https://youtu.be/TQ0sL1ZGnQ4 http://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer
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Connecting via SSH to a remote machine is second nature to some, but how does it work? Dr Steve Bagley. Dr Mike Pound on Hashing (mentions padding but full video on padding is planned to follow): https://youtu.be/DMtFhACPnTY https://www.facebook.com/computerphile Tweets by computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University
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