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Archive for the ‘By Alex’ Category

Alex: Linear and Non-Linear Video Editing Systems

Having just finished a video editing project, I find it fair to launch into an explanation here.

Video editing suites have changed substantially over the past couple of years. At the beginning, film was edited manually. The special effects of that age were limited and often simple. Even transitions were incredibly easy. 

The film industry term ‘cut’, to refer to a rapid change in scene (no less than 1 frame), is derived from the ancient technique of doing so. Back then, film strips were literally cut by the editor and pieced together again to form a final video. It was crude, and any error on the part of the editor would result in irreparable damage. You can imagine the pressure that they were under at that time.

It also meant that video editing was linear. Editors had to start at the beginning and piece everything together bit by bit. Sure, they could assemble everything outside of sequence, but it still went from the beginning and straight to the end. Nothing more.

A Sony BVE-910 linear editing system's keyboard

These controls were specially designed for linear video editing. Image via Wikipedia.

When computers were invented, they further enhanced the limitability of linear editing systems. At this point, random access still had not been invented, so that the editor had to load pieces up in order and assemble them like so. I have never run a linear editing system, so I can hardly go into the details.

Today, however, the majority of video editing happens on non-linear video editing software, like iMovie, Adobe Premiere, or Sony Vegas. These programs are use non-destructive video editing techniques, rather like how Adobe Photoshop works.

The principle is simple. These editing suites, instead of editing the video, simply write a text file stating the location of the video clip, which sections of the video clip to play, and then where that is placed in the relative timeline. This means that the original video file is never altered or edited — being non-destructive — but the fact it writes the relative position on the timeline also means that they could be rearranged at leisure. After all, you’re not moving about 1.5Gb of video data — you’re simply rewriting one line of text in a 1KB file.

Naturally, this revolutionised the film industry. Now, nearly all video editing takes place on some non-linear video editing software because of its ease.

The downside to using non-linear video editing software was that none of the actual video files were placed together. As a result, the software file itself was meaningless. To share the actual video, the user needed to render the video out, so that each individual bit was converted into a video, and assembled to form the final film. This process often took hours, perhaps even days, depending on the intensity of the editing. In other words, the system traded the time around, granting ease and speed of editing and increasing time needed to produce the product.

Premiere logo.

Adrian loves this program. Image via Wikipedia.

Still, Adobe Premiere runs fine on me, and I’m not complaining. Even if it does drain my RAM a bit. A bit more than a bit. 

Get the joke?

Alex: The Power of HTML — Hey, That’s My Language!

Written by Alex:

You see HTML referenced everywhere; it’s practically on every single corner of anything Internet related. On websites, on posting services (like WordPress), even in a tonne of reference books.

English: The XHTML source for Wikipedia.

What HTML/XHTML looks like. Image via Wikipedia.

HTML, in short, is the language of webpages. It is a standardised computing language that all web browsers understand, and is one of the backbones that allow webpages to be displayed similarly across different browsers and operating systems. (There’s also CSS, but that’s for another time.)

Español: Tim Berners-Lee En el Foro de la Gobe...

Tim Berners-Lee. Image via Wikipedia.

HTML stands for Hyper Text Markup Language, was invented by the physicist Tim Berners-Lee, the founder of the World Wide Web. Later on, when the internet became more accessible, it got messed up in the so-called browser wars. It became standardised by W3C and has evolved into its current state, HTML 5.

There’s also XHTML. XHTML stands for eXtensible Hyper Text Markup Language, and it’s basically a cross between XML and HTML. For most users, it’s okay to regard XHTML as a more powerful, but more picky version of HTML.

Okay, so that’s a history lesson over, now what does this have to do with anything Adrian’s doing?