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Has the way the 4:3 flag is broadcast been changed?

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  Has the way the 4:3 flag is broadcast been changed? "J. P. Gilliver" <G6JPG@255soft.uk> - 2026-09-07 21:28 +0100
    Re: Has the way the 4:3 flag is broadcast been changed? NY <me@privacy.net> - 2026-09-13 21:11 +0100
      Re: Has the way the 4:3 flag is broadcast been changed? "J. P. Gilliver" <G6JPG@255soft.uk> - 2026-09-13 22:39 +0100
      Re: Has the way the 4:3 flag is broadcast been changed? Brian Gregory <void-invalid-dead-dontuse@email.invalid> - 2026-09-13 23:39 +0100
        Re: Has the way the 4:3 flag is broadcast been changed? "J. P. Gilliver" <G6JPG@255soft.uk> - 2026-09-14 03:12 +0100
          Re: Has the way the 4:3 flag is broadcast been changed? Brian Gregory <void-invalid-dead-dontuse@email.invalid> - 2026-09-18 22:50 +0100
            Re: Has the way the 4:3 flag is broadcast been changed? "J. P. Gilliver" <G6JPG@255soft.uk> - 2026-09-19 00:36 +0100
          Re: Has the way the 4:3 flag is broadcast been changed? Brian Gregory <void-invalid-dead-dontuse@email.invalid> - 2026-09-18 22:57 +0100
            Re: Has the way the 4:3 flag is broadcast been changed? "J. P. Gilliver" <G6JPG@255soft.uk> - 2026-09-19 00:38 +0100
              Re: Has the way the 4:3 flag is broadcast been changed? Brian Gregory <void-invalid-dead-dontuse@email.invalid> - 2026-09-19 05:03 +0100
                Re: Has the way the 4:3 flag is broadcast been changed? "J. P. Gilliver" <G6JPG@255soft.uk> - 2026-09-19 22:01 +0100
      Re: Has the way the 4:3 flag is broadcast been changed? richard@cogsci.ed.ac.uk (Richard Tobin) - 2026-09-14 09:55 +0000
        Re: Has the way the 4:3 flag is broadcast been changed? NY <me@privacy.net> - 2026-09-14 14:37 +0100
          Re: Has the way the 4:3 flag is broadcast been changed? "J. P. Gilliver" <G6JPG@255soft.uk> - 2026-09-14 19:15 +0100
      Re: Has the way the 4:3 flag is broadcast been changed? wolfgang s <see@sig.nature> - 2026-09-18 09:19 +0000
        Re: Has the way the 4:3 flag is broadcast been changed? NY <me@privacy.net> - 2026-09-18 13:09 +0100
          Re: Has the way the 4:3 flag is broadcast been changed? "J. P. Gilliver" <G6JPG@255soft.uk> - 2026-09-18 22:13 +0100
          Re: Has the way the 4:3 flag is broadcast been changed? Brian Gregory <void-invalid-dead-dontuse@email.invalid> - 2026-09-18 22:42 +0100
          Re: Has the way the 4:3 flag is broadcast been changed? wolfgang s <see@sig.nature> - 2026-09-20 19:03 +0000

#70528 — Has the way the 4:3 flag is broadcast been changed?

(Or have they stopped bothering?) SD Freeview.

On my elderly but still functional Panasonic TV (TX-L22X20B), when 4:3
material was being transmitted - properly, rather than including the
black bars sometimes with a dog in them - such as the original (and
sometimes startlingly green due to film fading!) All Creatures Great and
Small, and assorted other programmes (such as some BBC4 archive music
programmes), the TV displayed it wrongly - i. e. filling the full width,
so appearing squashed or stretched - unless I turned the subtitles off.
(I presume doing subtitles _and_ rendering the picture pillarboxed was
just too much processing load for whatever processor it contains.) If I
turned subtitles off, the picture appeared properly pillarboxed.

But recently, such material is filling the screen whether I turn the
subtitles off or not; I've noticed it on the Catherine Cookson stuff on
channel 20 on Sunday afternoons (I _think_ that has changed and used to
be displayable correctly), and I'm seeing it now on the Mastermind 1977
being shown on channel 9 (BBC Four) now (Monday 7, 21:00) - i. e. it's
appearing full-screen, so squashed or stretched, regardless of whether I
have subtitles on or not.

Since I very much doubt there has been any OTA firmware "up" (down) date
of such an old set, have the broadcasters just abandoned setting the
flag altogether? Seems to apply to both BBC and whoever is responsible
for channel 20 (U&Drama). (If they have, I'd rather have the broadcast
include the side black bars - at least the picture would not be distorted.)

On my bedrrom setup (HD-capable TEKNIKAL set-top box), BBC4 SD on
channel 9 is also showing the old Mastermind full-screen (stretched); on
HD (channel 106) it is showing correctly, i. e. pillarboxed. (Toggling
subtitles makes no difference on either resolution, but I wasn't
expecting it to on that setup.)
-- 
J. P. Gilliver. UMRA: 1960/<1985 MB++G()ALIS-Ch++(p)Ar++T+H+Sh0!:`)DNAf

-I said to myself, "If it's my time to go to hell, I'm takin' him with
me." - 82-yo lady bodybuilder after beating up a burglar (odJRDx3tA0w)

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#70529

On 07/09/2026 21:28, J. P. Gilliver wrote:
> (Or have they stopped bothering?) SD Freeview.
> 
> On my elderly but still functional Panasonic TV (TX-L22X20B), when 4:3
> material was being transmitted - properly, rather than including the
> black bars sometimes with a dog in them - such as the original (and
> sometimes startlingly green due to film fading!) All Creatures Great and
> Small, and assorted other programmes (such as some BBC4 archive music
> programmes), the TV displayed it wrongly - i. e. filling the full width,
> so appearing squashed or stretched - unless I turned the subtitles off.
> (I presume doing subtitles _and_ rendering the picture pillarboxed was
> just too much processing load for whatever processor it contains.) If I
> turned subtitles off, the picture appeared properly pillarboxed.
> 
> But recently, such material is filling the screen whether I turn the
> subtitles off or not; I've noticed it on the Catherine Cookson stuff on
> channel 20 on Sunday afternoons (I _think_ that has changed and used to
> be displayable correctly), and I'm seeing it now on the Mastermind 1977
> being shown on channel 9 (BBC Four) now (Monday 7, 21:00) - i. e. it's
> appearing full-screen, so squashed or stretched, regardless of whether I
> have subtitles on or not.
> 
> Since I very much doubt there has been any OTA firmware "up" (down) date
> of such an old set, have the broadcasters just abandoned setting the
> flag altogether? Seems to apply to both BBC and whoever is responsible
> for channel 20 (U&Drama). (If they have, I'd rather have the broadcast
> include the side black bars - at least the picture would not be distorted.)
> 
> On my bedrrom setup (HD-capable TEKNIKAL set-top box), BBC4 SD on
> channel 9 is also showing the old Mastermind full-screen (stretched); on
> HD (channel 106) it is showing correctly, i. e. pillarboxed. (Toggling
> subtitles makes no difference on either resolution, but I wasn't
> expecting it to on that setup.)

Some channels use the widescreen flag properly: they broadcast 4:3 
archive programmes using the full 720 pixels of width, and set the flag 
to tell the TV "display this in the centre of the screen and do not 
stretch 4:3 to 16:9". Some of the UKTV channels (eg Drama, Yesterday) 
used to do this at every transition between 16:9 adverts and 4:3 programme.

Mainstream channels such as BBC1 and ITV broadcast everything as 16:9, 
so 4:3 programmes occupy the centre of the 16:9 frame and hence only a 
proportion of the 720 pixels are used: the rest is used for the black 
border. This means that the horizontal resolution of the picture is crap 
(to use a technical term!).

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#70530

On 2026/9/13 21:11:58, NY wrote:
[]
> Some channels use the widescreen flag properly: they broadcast 4:3 
> archive programmes using the full 720 pixels of width, and set the flag 
> to tell the TV "display this in the centre of the screen and do not 
> stretch 4:3 to 16:9". Some of the UKTV channels (eg Drama, Yesterday) 
> used to do this at every transition between 16:9 adverts and 4:3 programme.

But in the last month or so (?), I've found cases where - same channel,
same actual programme - I cannot now display the picture unstretched,
where I could before. Hence my query. In other words, they're still
using the full 720 pixels (or whatever) of width - no actual
transmission of black sidebars - but they've stopped using the flag
properly. I see it as a combination of don't knoq/don't care (most
likely), and (if paranoid) a deliberate attempt to make archive material
look bad.>
> Mainstream channels such as BBC1 and ITV broadcast everything as 16:9, 
> so 4:3 programmes occupy the centre of the 16:9 frame and hence only a 
> proportion of the 720 pixels are used: the rest is used for the black 
> border. This means that the horizontal resolution of the picture is crap 
> (to use a technical term!).

Ah, but at least they can put a DOG in the black bit. :-)
-- 
J. P. Gilliver. UMRA: 1960/<1985 MB++G()ALIS-Ch++(p)Ar++T+H+Sh0!:`)DNAf

All that glitters has a high refractive index.

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#70531

HD is always 16:9 and there is, as far as I know, no flag.
It's up to the people who configure things at the studio and transmitter 
to correctly add appropriate black bars when necessary.

-- 
Brian Gregory (in England).

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#70532

On 2026/9/13 23:39:25, Brian Gregory wrote:
> HD is always 16:9 and there is, as far as I know, no flag.
> It's up to the people who configure things at the studio and transmitter 
> to correctly add appropriate black bars when necessary.
> 
Yes, the relevant prog.s (e. g. vintage Mastermind), when I looked on my
HD set (when they were being broadcast on an HD channel as well as an SD
one), were correctly pillarboxed. It's just when viewed on my SD set (on
an SD channel, obviously), or the HD set on an SD channel, they have
started to appear full-screen, and thus distorted (squashed/stretched).
Until sometime in the last month or so, that set displayed such material
pillarboxed automatically (though for some reason I had to turn
subtitles off for that to work). Now it doesn't; I can only assume that
the broadcasters - who are clearly broadcasting the material full-width
- have stopped setting the flag.
-- 
J. P. Gilliver. UMRA: 1960/<1985 MB++G()ALIS-Ch++(p)Ar++T+H+Sh0!:`)DNAf

The beauty of a double entendre is that it only means one thing
- attributed to Ronnie Barker

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#70541

On 14/09/2026 03:12, J. P. Gilliver wrote:
> Yes, the relevant prog.s (e. g. vintage Mastermind), when I looked on my
> HD set (when they were being broadcast on an HD channel as well as an SD
> one), were correctly pillarboxed. It's just when viewed on my SD set (on
> an SD channel, obviously), or the HD set on an SD channel, they have
> started to appear full-screen, and thus distorted (squashed/stretched).

I think maybe it's just being done because some people (idiots?) like it 
better that way.

"I paid a fortune for this huge screen, why aren't you using all of it?"

Much in the same way that some people will stretch a photo to fill a gap 
left for it on a website even if it means the photo gets horribly 
stretched or squashed.

-- 
Brian Gregory (in England).

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#70543

On 2026/9/18 22:50:46, Brian Gregory wrote:
> On 14/09/2026 03:12, J. P. Gilliver wrote:
>> Yes, the relevant prog.s (e. g. vintage Mastermind), when I looked on my
>> HD set (when they were being broadcast on an HD channel as well as an SD
>> one), were correctly pillarboxed. It's just when viewed on my SD set (on
>> an SD channel, obviously), or the HD set on an SD channel, they have
>> started to appear full-screen, and thus distorted (squashed/stretched).
> 
> I think maybe it's just being done because some people (idiots?) like it 
> better that way.
> 
> "I paid a fortune for this huge screen, why aren't you using all of it?"

I remember when shortscreen sets first appeared - back in CRT days - it
was around one Wimbledon, which wasn't being broadcast in Widescreen;
but a lot of people seemed to have that attitude (or didn't know any
better). Now male tennis players are quite chunky already, or a lot of
them are; but seen squashed to fit a short screen, they looked
positively Neanderthal.>
> Much in the same way that some people will stretch a photo to fill a gap 
> left for it on a website even if it means the photo gets horribly 
> stretched or squashed.
> 
Yes. At least X (twitter) tends to use original aspect ratio, or at
least the people I follow do - though that leads to a different problem
for one of those I follow, as he uses a camera (presumably a 'phone)
that seems to have about a 3:1 ratio. (And he will insist on using it
vertically, and most of what he posts are landscapes.)
-- 
J. P. Gilliver. UMRA: 1960/<1985 MB++G()ALIS-Ch++(p)Ar++T+H+Sh0!:`)DNAf

The voices of Radio 4 continuity and newsreading have been keeping me
right for as long as I can remember. I can call on a million different
information sources, but it doesn't make sense unti I've heard it from
Peter, Harriet, Charlotte and the rest.
- Eddie Mair in Radio Times 10-16 November 2012

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#70542

On 14/09/2026 03:12, J. P. Gilliver wrote:
> Yes, the relevant prog.s (e. g. vintage Mastermind), when I looked on my
> HD set (when they were being broadcast on an HD channel as well as an SD
> one), were correctly pillarboxed. It's just when viewed on my SD set (on
> an SD channel, obviously), or the HD set on an SD channel, they have
> started to appear full-screen, and thus distorted (squashed/stretched).
> Until sometime in the last month or so, that set displayed such material
> pillarboxed automatically (though for some reason I had to turn
> subtitles off for that to work). Now it doesn't; I can only assume that
> the broadcasters - who are clearly broadcasting the material full-width
> - have stopped setting the flag.

Have you ever seen any of the Indian news channels on satellite? They 
are full of feeds from events or remote studios at the wrong aspect ratio?

I suspect the BBC is almost unique among the worlds broadcasters in 
really wanting to do everything correctly and in the highest possible 
quality.

-- 
Brian Gregory (in England).

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#70544

On 2026/9/18 22:57:14, Brian Gregory wrote:
> On 14/09/2026 03:12, J. P. Gilliver wrote:
>> Yes, the relevant prog.s (e. g. vintage Mastermind), when I looked on my
>> HD set (when they were being broadcast on an HD channel as well as an SD
>> one), were correctly pillarboxed. It's just when viewed on my SD set (on
>> an SD channel, obviously), or the HD set on an SD channel, they have
>> started to appear full-screen, and thus distorted (squashed/stretched).
>> Until sometime in the last month or so, that set displayed such material
>> pillarboxed automatically (though for some reason I had to turn
>> subtitles off for that to work). Now it doesn't; I can only assume that
>> the broadcasters - who are clearly broadcasting the material full-width
>> - have stopped setting the flag.
> 
> Have you ever seen any of the Indian news channels on satellite? They 
> are full of feeds from events or remote studios at the wrong aspect ratio?
> 
> I suspect the BBC is almost unique among the worlds broadcasters in 
> really wanting to do everything correctly and in the highest possible 
> quality.
> 
They're better than many - but the vintage Mastermind I was watching was
on a BBC channel (2 or 4). The HS version (102 or 106) _was_ correctly
pillarboxed, but the SD one was not.
-- 
J. P. Gilliver. UMRA: 1960/<1985 MB++G()ALIS-Ch++(p)Ar++T+H+Sh0!:`)DNAf

The voices of Radio 4 continuity and newsreading have been keeping me
right for as long as I can remember. I can call on a million different
information sources, but it doesn't make sense unti I've heard it from
Peter, Harriet, Charlotte and the rest.
- Eddie Mair in Radio Times 10-16 November 2012

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#70545

On 19/09/2026 00:38, J. P. Gilliver wrote:
> They're better than many - but the vintage Mastermind I was watching was
> on a BBC channel (2 or 4). The HS version (102 or 106) _was_ correctly
> pillarboxed, but the SD one was not.

Ah, now that does seem unusual to me, but recently I haven't been 
watching a huge amount of off air TV.

Perhaps you should double check you don't have a setting like 
Letterbox/PanScan/Scale/Auto somewhere in you TV or set top box that has 
been set wrongly. My satellite box has this, and weirdly PanScan is the 
correct setting, not Auto! I think I've seen similar settings on TVs too.

-- 
Brian Gregory (in England).

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#70549

On 2026/9/19 5:3:30, Brian Gregory wrote:
> On 19/09/2026 00:38, J. P. Gilliver wrote:
>> They're better than many - but the vintage Mastermind I was watching was
>> on a BBC channel (2 or 4). The HD version (102 or 106) _was_ correctly
>> pillarboxed, but the SD one (2 or 9) was not.
> 
> Ah, now that does seem unusual to me, but recently I haven't been 
> watching a huge amount of off air TV.
> 
> Perhaps you should double check you don't have a setting like 
> Letterbox/PanScan/Scale/Auto somewhere in you TV or set top box that has 
> been set wrongly. My satellite box has this, and weirdly PanScan is the 
> correct setting, not Auto! I think I've seen similar settings on TVs too.
> 
Good steer, but I am aware of all those settings in my TV and box - in
particular, on one of my TVs, it would display 4:3 material, broadcast
with the correct flag, correctly pillarboxed if I turned the subtitles
off (!). But suddenly that no longer caused such material to be
displayed correctly - hence my original post in this thread; it was
prompted by some programme, same time same channel(s), that previously
had displayed correctly, now not doing so.
-- 
J. P. Gilliver. UMRA: 1960/<1985 MB++G()ALIS-Ch++(p)Ar++T+H+Sh0!:`)DNAf

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#70533

In article <118702e$u449$1@dont-email.me>, NY  <me@privacy.net> wrote:

>Mainstream channels such as BBC1 and ITV broadcast everything as 16:9, 
>so 4:3 programmes occupy the centre of the 16:9 frame and hence only a 
>proportion of the 720 pixels are used: the rest is used for the black 
>border. This means that the horizontal resolution of the picture is crap 
>(to use a technical term!).

Do they use the same bitrate as for 16:9 programs?  If so, there
should be less compression which will to some extent compensate
for the lower resolution.

-- Richard

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#70534

On 14/09/2026 10:55, Richard Tobin wrote:
> In article <118702e$u449$1@dont-email.me>, NY  <me@privacy.net> wrote:
> 
>> Mainstream channels such as BBC1 and ITV broadcast everything as 16:9,
>> so 4:3 programmes occupy the centre of the 16:9 frame and hence only a
>> proportion of the 720 pixels are used: the rest is used for the black
>> border. This means that the horizontal resolution of the picture is crap
>> (to use a technical term!).
> 
> Do they use the same bitrate as for 16:9 programs?  If so, there
> should be less compression which will to some extent compensate
> for the lower resolution.
Very true. Except... Old 4:3 programmes were made using analogue cameras 
and stored on analogue videotape. This introduces noise that doesn't 
compress well. BBC channels often increase the bitrate of 
made-on-analogue archive programmes to compensate for this. Some other 
broadcasters don't bother - and the picture quality is worse.

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#70535

On 2026/9/14 14:37:41, NY wrote:
> On 14/09/2026 10:55, Richard Tobin wrote:
>> In article <118702e$u449$1@dont-email.me>, NY  <me@privacy.net> wrote:
>>
>>> Mainstream channels such as BBC1 and ITV broadcast everything as 16:9,
>>> so 4:3 programmes occupy the centre of the 16:9 frame and hence only a
>>> proportion of the 720 pixels are used: the rest is used for the black
>>> border. This means that the horizontal resolution of the picture is crap
>>> (to use a technical term!).
>>
>> Do they use the same bitrate as for 16:9 programs?  If so, there
>> should be less compression which will to some extent compensate
>> for the lower resolution.

And, if there is compression, the side black bits should compress almost
to nothing, which should also add to the available bits.

> Very true. Except... Old 4:3 programmes were made using analogue cameras 
> and stored on analogue videotape. This introduces noise that doesn't 
> compress well. BBC channels often increase the bitrate of 
> made-on-analogue archive programmes to compensate for this. Some other 
> broadcasters don't bother - and the picture quality is worse.

I didn't know that. Though professional-quality VTRs would have pretty
low noise.
-- 
J. P. Gilliver. UMRA: 1960/<1985 MB++G()ALIS-Ch++(p)Ar++T+H+Sh0!:`)DNAf

"Farc gorillas who live in the plains of the undies ..."
- automatic subtitling seen on BBC one o'clock news, 2016-8-25,
by Cynthia Hollingworth.

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#70536

NY <me@privacy.net> wrote in news:118702e$u449$1@dont-email.me:

> Mainstream channels such as BBC1 and ITV broadcast everything as 16:9, 
> so 4:3 programmes occupy the centre of the 16:9 frame and hence only a 
> proportion of the 720 pixels are used: the rest is used for the black 
> border. This means that the horizontal resolution of the picture is
> crap (to use a technical term!).

The effective resolution left is 540x576. That is absolutely adequate 
for SD. 720 pixel columns is higher resolution than analogue PAL ever 
was.

-- 
Currently listening:  https://www.youtube.com/watch?v=_yMTnAw0yYg

http://www.wschwanke.de/  usenet_20031215 (AT) wschwanke (DOT) de

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#70538

On 18/09/2026 10:19, wolfgang s wrote:
> NY <me@privacy.net> wrote in news:118702e$u449$1@dont-email.me:
> 
>> Mainstream channels such as BBC1 and ITV broadcast everything as 16:9,
>> so 4:3 programmes occupy the centre of the 16:9 frame and hence only a
>> proportion of the 720 pixels are used: the rest is used for the black
>> border. This means that the horizontal resolution of the picture is
>> crap (to use a technical term!).
> 
> The effective resolution left is 540x576. That is absolutely adequate
> for SD. 720 pixel columns is higher resolution than analogue PAL ever
> was.

Is it? I thought that 720 was chosen specifically (*) to be about 4/3 of 
the number of rows (576), after the Kell Factor for interlacing is taken 
into account (ie the *perceived* vertical resolution of an interlaced 
display is less than for a progressive display).

Given that almost every TV nowadays uses a non-CRT display, so the whole 
screen is illuminated for the whole frame, interlaced or progressive is 
fairly irrelevant: it's a difference only of delivery, rather than of 
display.


(*) In the same way that the analogue bandwidth was limited to about 5.5 
MHz which limits horizontal resolution. 5.5*10^6 / (625*25) = 352, which 
is 352 pairs of alternate black/white pixels, so 704 pixels in total. 
And lo-and-behold, that's exactly the resolution that the BBC uses, 
whereas a lot of other broadcasters add 16 pixels to give 720.

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#70539

On 2026/9/18 13:9:11, NY wrote:
[]
> Given that almost every TV nowadays uses a non-CRT display, so the whole 
> screen is illuminated for the whole frame, interlaced or progressive is 
> fairly irrelevant: it's a difference only of delivery, rather than of 
> display.

Mostly true, but not entirely: fast-moving things have more ragged edges
via i, assuming the movement is horizontal.

The main improvement with constant lighting is the removal of flicker,
the avoidance of which was a _main_ reason to use 50 or 60 (the
bandwidth reduction being the other [reason for interlacing]); now we
have steady lighting, it can be seen that an actual rate of 10 or 12 is
sufficient for many subjects.
[]
-- 
J. P. Gilliver. UMRA: 1960/<1985 MB++G()ALIS-Ch++(p)Ar++T+H+Sh0!:`)DNAf

There are two kinds of fool. One says, "This is old, and therefore
good." And one says, "This is new, and therefore better."
-John Brunner, science fiction writer (1934-1995)

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#70540

On 18/09/2026 13:09, NY wrote:
> (*) In the same way that the analogue bandwidth was limited to about 5.5 
> MHz which limits horizontal resolution. 5.5*10^6 / (625*25) = 352, which 
> is 352 pairs of alternate black/white pixels, so 704 pixels in total. 
> And lo-and-behold, that's exactly the resolution that the BBC uses, 
> whereas a lot of other broadcasters add 16 pixels to give 720.

Have you noticed that some stations use 704*576 but sent as 720*576 with 
8 black pixels at beginning and end of each line. Very annoying on 
modern flat screens that usually show every pixel sent.

-- 
Brian Gregory (in England).

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#70551

NY <me@privacy.net> wrote in news:118j9l8$18lvp$1@dont-email.me:

>> The effective resolution left is 540x576. That is absolutely adequate
>> for SD. 720 pixel columns is higher resolution than analogue PAL ever
>> was.
> 
> Is it? I thought that 720 was chosen specifically (*) to be about 4/3 of 
> the number of rows (576),

4:3 would be exactly 768x576, and that is a format actually used in 
some editing systems. But this an idealistic value that was never 
achieved in the analogue era. Even 720 wasn't.

> Given that almost every TV nowadays uses a non-CRT display, so the whole 
> screen is illuminated for the whole frame, interlaced or progressive is 
> fairly irrelevant: it's a difference only of delivery, rather than of 
> display.

Yeah but if the original content never had 720 pixels per line to begin 
with, it doesn't matter if they throw away part of it by cropping the 
sides. And it doesn't:
 
> (*) In the same way that the analogue bandwidth was limited to about 5.5 
> MHz which limits horizontal resolution. 5.5*10^6 / (625*25) = 352, which 
> is 352 pairs of alternate black/white pixels, so 704 pixels in total. 

Yes absolutely, but you're forgetting something: The sync pulse took up 
about 20 percent of each line, leaving roughly 282 cycles, which 
applying Nyquist requires 564 pixels.

So if they broadcast an analogue era video production at 720x576 
widescreen and black side panels cropped to 540 pixels, you are still 
getting the full resolution of that videotape, or at least close enough.

-- 
Currently listening:  https://www.youtube.com/watch?v=_yMTnAw0yYg

http://www.wschwanke.de/  usenet_20031215 (AT) wschwanke (DOT) de

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