Interlaced Scan Rendering (TV broadcast formats)

NTSC

NTSC is based on a 525-line, 60 fields/30 frames-per-second at 60Hz system for transmission and display of video images. This is an interlaced system in which each frame is scanned in two fields of 262 lines, which is then combined to display a frame of video with 525 scan lines. NTSC is the official analog video standard in the U.S., Canada, Mexico, some parts of Central and South America, Japan, Taiwan, and Korea.

PAL is the dominant format in the World for analog television broadcasting and video display (sorry U.S.) and is based on a 625 line, 50 field/25 frames a second, 50HZ system. The signal is interlaced, like NTSC, into two fields, composed of 312 lines each. Several distinguishing features are one: A better overall picture than NTSC because of the increased amount of scan lines. Two: Since color was part of the standard from the beginning, color consistency between stations and TVs are much better. In addition, PAL has a frame rate closer to that of film. PAL has a 25 frames per second rate, while film has a frame rate of 24 frames per second. Countries on the PAL system include the U.K., Germany, Spain, Portugal, Italy, China, India, most of Africa, and the Middle East.

Progressive Scan

With the advent of home and office desktop computers, it was discovered that using a traditional television for the display of computer images did not yield good results, especially with text. This was due to the effect of interlaced scan. In order to produce a more pleasing and precise way of displaying images on a computer, progressive scan was developed.

Progressive scan differs from interlaced scan in that the image is displayed on a screen by scanning each line (or row of pixels) in a sequential order rather than an alternate order, as is done with interlaced scan. In other words, in progressive scan, the image lines (or pixel rows) are scanned in numerical order (1,2,3) down the screen from top to bottom, instead of in an alternate order (lines or rows 1,3,5, etc... followed by lines or rows 2,4,6). By progressively scanning the image onto a screen every 60th of a second rather than "interlacing" alternate lines every 30th of a second, a smoother, more detailed, image can be produced on the screen that is perfectly suited for viewing fine details, such as text, and is also less susceptible to interlace flicker.

Seeing this technology as way to improve the way we view images on a television screen, progressive scan has now been applied to the display of DVD and certain types of HDTV images.

Dolby Digital
Dolby Digital is a digital encoding system for audio signals that can be decoded by a receiver or preamplifier with a Dolby Digital decoder.

Dolby Digital is often referred to as a 5.1 channel surround system. However, it must be noted that term "Dolby Digital" refers to the digital encoding of the audio signal, not how many channels it has. In other words, Dolby Digital can be Monophonic, 2-channel, 4-channel, 5.1 channels, or 6.1 channels. However, in its most common applications, Dolby Digital 5.1 and 6.1 are often referred to as just Dolby Digital.

Best Takeaway in London

Mini-DV
Launched by Sony in 1995, DV (or Mini-DV) is the most popular consumer digital video format. DV camcorders provide what is arguably the best quality of all of the home video formats, with all models possessing the capability to transfer video signals out to another device (such as a Windows or Apple Mac computer) via FireWire – also known as i.Link. An increasing number of DV camcorders also make it possible to copy edited recordings back to the DV tape in the camcorder using what is known as DV-in;

Digital-8
This format was introduced by Sony in the late 1990s and uses 8mm videocassettes (as used by Video-8 or Hi-8) to record and replay a video signal identical to DV. Signals use FireWire (i.Link) to transfer a DV-specification signal out and – where appropriate – back in to the camcorder. Some Digital-8 models will enable users to insert standard analogue Video-8 and Hi-8 tape recordings and play them back, in addition to converting the signals as they are passed via FireWire to a computer for editing. Note that Digital-8 is a format that is being phased out by Sony, so consider with caution.

DVD
Hitachi first launched camcorders that record to 8cm DVD disks back in 2001, and several other major manufacturers soon followed suit. Like MICROMV, DVD camcorders use MPEG-2 compression prior to writing the signals to disk. One of the major problems of DVD camcorders has been the compatibility between DVD camcorders and home DVD players, though these are quickly being resolved. If you're planning to import your DVD footage into a computer for editing, you should note that editing DVD (MPEG2) compressed files is much more difficult than it is when working with a tape-based format like DV or Digital-8. Existing editing applications (as with those that are bundled with camcorders) aren't that good. However, the format is now very popular, and not everyone wishes to edit their movie projects;

HDD (Hard Disk Drive)
JVC is one company that is forging ahead with its drive to make Hard Disk recording camcorders more popular and push tape and disk-based formats aside altogether. The Everio G camcorder range is a good example of camcorders - or Digital Media Cameras as they're more properly called - which uses tiny internal hard disk drives very similar to the larger HDs used in all computers. The company's GZ-MG50 model enables recording of up to 7 hours at best quality. Apple's iPod MP3 players use very similar technology and provide a similar level of interactivity with the files saved onto them. HDD camcorders save files which can then be deleted, moved and transferred just like those on your computer or iPod. They also provide much more flexibility in terms of the order in which you can produce a playlist of favourite clips when showing people your material;

Solid-State
Also known as CardCams, these camcorders don't have any moving parts, tape, disk or otherwise. Instead, they record a compressed video stream to either a built-in memory chip or to a removeable card, such as an SD card as used in many digital still cameras. The Sanyo Xacti is an example of a Solid State camcorder. Whilst they're very handy, they're not suited to serious uses. In fact, they're pretty much a slightly higher quality equivalent of the video clips that can be shot with many modern mobile phones;

MicroDrive
Very similar in the way they're used to HDD camcorders, cams that record to MicroDrives use small, removeable drive units that provide up to 4GB (Gigabytes) capacity. MicroDrives are very expensive to buy, however, and at best quality they'll only store 60 minutes of video footage. Having experimented with its Everio range that use MicroDrives, JVC is now likely to concentrate on development of HDD models;

MICROMV
MICROMV is a format that was introduced by Sony with great optimism in 2001 that uses cassettes that are 70% of the size of DV cassettes which records in a format called MPEG-2, which is similar to that used in DVD disks. Although the limited number of MICROMV camcorders available contain i.Link connectors, it isn’t possible to transfer video to a computer without the use of special computer software (other than supplied by Sony with its models). Sony offers only one MICROMV model camcorder, and when that is withdrawn the format itself will be considered obsolete;

HDV and ProHD
HDV stands for High Definition Video (although some refer to it as High-Def DV) and Sony's format uses standard MiniDV cassettes to record video sequences whose resolution is 1080-lines as opposed to the standard definition 625 lines (or 525 in the USA, Canada, Japan, etc). HDV is fast becoming the format of choice for those wishing to shoot professional-quality video footage, not least because it offers the choice of HDV or DV recording on a MiniDV tape. ProHD is the JVC equivalent format of HDV;

DVCAM and DVCPRO
These are two formats that are based upon DV but which use a higher-specification recording system to produce pictures that are acceptable to broadcast TV channels and professional video producers. DVCAM is Sony's format, whereas DVCPRO is a format that was pioneered by Panasonic.

Cranes, West India Docks, London, originally uploaded by Craig Grobler.

The West India Docks are a series of three docks on the Isle of Dogs in London. Part of the original dock buildings now houses entertainment and leisure facilities such as the Museum in Docklands, 1802, The Ledger Building, Beluga Cafe, La Tasca, Leven Is Strijd, Bar 38, Dion and Scuzi.

I popped in for lunch at Scuzi and felt strangely at home while at the West India Docks. It became apparent that the architecture had it's roots in Dutch heritage which a lot of South Africa does as well. I'm not talking about old school Cape Dutch architecture but rather contemporary architecture as seen in the Cape waterfront and surrounding areas.

The docks remain open to ships and are now effectively protected from future major change by national and London Government policy. South Dock regularly plays host to medium-sized military vessels visiting London as it is the furthest point upstream that they can be turned around.

In 2005 planning permission was granted for a floating hotel in the shape of a modern yacht to be berthed in the South Dock, it seems that this will be a reality in the next 5 years.