29 October, 2006

Format wars – Consumer Video

Format wars – Consumer Video

(O.K, I know, it’s been over two weeks – I do have a life)

For those of you old enough (and most of my 5 readers are) the Beta vs. VHS format wars on the home front along with the much smaller market of VideoDisk vs. PhonoVision and the DVD vs Dvix

Now there is a another battle looming between the “Blu-Ray” and the HD-DVD camps, for those of us who live outside of the larger DMA’s and for whatever reasons don’t have a DTH dish the only way you will see a true HD picture for some time is going to be from one of these.

One of these (Blu-Ray) uses a higher frequency laser with a shorter wavelength (4050 Angstroms) than the current DVD (and CD) of 6500 Angstroms so the cost of backwards compatibility and retooling of existing manufacturing means the dual layer HD-DVD will hit the market first and at a much lower initial cost.

Blu-Ray has the edge in storage, currently at about 50GB capacity for a single layer vs 30GB for dual layer HD-DVD and potential exists for multi layer capacity of over 100GB with is enough to store over 100 hours of standard definition video – all of the original Star Trek including bloopers and outtakes on one disk anyone?

If we go back to the Beta vs VHS wars there were several factors that contributed to the outcome

Betamax was a (marginally) better format, based on a ¾” industrial transport and threading scheme scaled down to a ½” form factor - also used in the pro BetaCam. Initially the consumer format limited to 1 hour per tape (BI on 500M) then BII had two hours but with a noticeable degradation and then eventually BIII with a tape speed so slow you could edit out commercials without a glitch during recording with the pause switch, initial consumer units were Mono for some time and until BetaHiFi the standard audio was nothing special and at BIII was awful.

VHS was cheaper to make, the modified M wrap is a less precise mechanism than Beta and the quality was never quite as good as the equivalent Beta although the SVHS format was quite good for its day it only showed its advantage if the tape was recorded from a
S-Video source (and displayed on a S-Video input monitor) and no rental distribution tapes were ever recorded that way. VHS had two other advantages, it started with two hour capacity so most movies could fit on one tape, and one of the dirty little secrets of the video rental industry – there was porn on VHS and not on Beta.

So the real driver of this battle will be the content providers, if you search the ‘net you will find 1000’s of hits for HD-DVD vs Blu-Ray, funny thing is most of them are over a year ago debating the ’05 holiday season – the content providers are reluctant to release their product in HD without some control over copying – a loosing battle.

09 October, 2006


Got a set of questions from a gate keeper at some 800lb gorilla of a company on at least it’s 3rd attempt to control a portion of the glass teat (nod to Harlan Ellison), makes one wonder just how anything gets done there

1) What are the NTSC & PAL frame rates?

NTSC (color) is 29.97 Frames per second (Monochrome - B&W) is exactly 30 Frames per second
PAL (and SECAM) is 25 Frames per second

2) Are you familiar with Telecine?
an open question, a Telecine is a device for transferring motion picture images from film to video, when transferring to PAL from the typical 24 Frame Per Second (actually, modern film is "double shuttered" each frame is projected twice for 48 images per second) there is a one to one movie frame to video frame correspondence slightly slowing the run time of the film when viewed, for transfer to NTSC (other than film shot as Todd AO which is 30fps) a 3:2 pull down sequence is used where alternating frames of movie are 'written' as 3 fields then 2 fields maintaining a realtime correspondence between the movie and video

Most MPEG encoders have an 'inverse telecine' function where repeated fields are detected and only process the first instance of the image

3) What is full D-1 resolution for NTSC & PAL?
the question is not correctly phrased and shows ignorance of the subject matter at hand - thanks for playing - don't call us, we'll call you

image resolution is the result of a combination of factors determined primarily by objective size, lens MTF (Modulation Transfer Function), Imaging device type and size

D-1 is an un compressed component digital video tape format that records a 270Mbps serial digital stream

this stream specification is correctly specified as ITU-R BT.601 (formerly known as CCIR 601) or SMPTE 259M and supports both PAL and NTSC line and frame rates (PAL is 625 lines including Vertical blanking, NTSC is 525 lines at the frame rates noted above) sampling the luminance at 720 (with at least 8 bits of resolution) and the two chroma difference values (at least 4 bits of resolution) at 360 times Per line often referred to as YUV 4:2:2 encoding

4) Are you familiar with H.264?


we'll see if I get a call back, until then, I’m not holding my breath