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720p V 1080i: Whats Better For Fast-action Sport?


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This program was shot in 1080i60 (or at least finished in i). They then made a 60-50 digital conversion, without decent motion compensation. The Aust copy was 1080i50

The zooming and panning impressed me; seemed better than what is normally available.

However, faced with the above information that the Art Museum program was 1080i60 converted to 1080i50 and then somehow broadcast by the ABC at 720p50, plus doubts raised in other posts, I have to ask:

Are there
any
programs that ABC HD receives from overseas for broadcast in Australia that are in true 50p, i.e. not converted from 50i, and not 50p derived from film scanned at 25fps?

Is the only material ABC HD broadcasts in true 50p certain programs it produces in the studio for live broadcast?

Does ABC HD broadcast any true 50p material at all?

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Searching the net for more info about NHK, the Japanese television broadcaster that producted the Art Museum programs, I came across this interesting snippet:

NHK, which first began research into HD in 1964, has now started public testing of the next-generation Ultra HD standard in 2007. NHK's Ultra HD technology includes a resolution of 7680 x 4320, which is up to 16X clearer than HDTV. The prototype super-fast cameras can capture data at a rate of 4,000 frames per second and the audio component is 22.2 (as compared to today’s 5.1 surround sound).

Full article here.

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I'm a digital TV newbie and am trying to digest the information in this forum particularly in respect to motion blur.

First off, I have a Sony 46X LCD with quoted response time of 8ms. Rounding up to 10ms that would seem to indicate that it can cope with 100 refreshes a second - much faster than would ever be asked of it and certainly much faster than the 24/25 fps that movies use without getting blur.

From what I am hearing here, motion blur is an artifact of either image compression or of scaling - is this correct?

One thing I have noticed is that a Blu-Ray Casino Royal disk played through a PS3 has more motion blur than e.g. the HD Shrek that Ch 9 broadcast last weekend (it looked absolutely brilliant). I guess this leads to the question - who but the blur in Blu-Ray! :blink:

Also if the LCD refresh rate is more than enough, why the Shervo ads saying Plasma does so much better?

Would appreciate anyone putting me right!

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Guest tom smud

ive noticed that ch 7 have been broadcasting afl in sd ...do u think its because thereve gotton a lot of complaints about the blocking artifacts during high activity [and perhaps they can swing their cameras more wildly to provide better football coverage]

cause i reckon that the little square blocks all over my screen happened a lot more on 7 that 10 and i dont beleive its because 7 got more games with higher activity rates

do u think 9 would have had less touble with this had they had the the rights

on a personal note..EDDIE AND HIS TEAM SUC

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From what I am hearing here, motion blur is an artifact of either image compression or of scaling - is this correct?

Also if the LCD refresh rate is more than enough, why the Shervo ads saying Plasma does so much better?

Motion blur is a flaw with your lcd screen. Look at a good plasma screen compared to your sony lcd and you will see much less motion blur.

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From what I am hearing here, motion blur is an artifact of either image compression or of scaling - is this correct?

Also if the LCD refresh rate is more than enough, why the Shervo ads saying Plasma does so much better?

The compression of the source video can cause video with fast motion to 'break up', but this is not strictly motion blur (it looks horrible nonetheless). To see this, watch HDTV football during fast pans on a screen not affected by motion blur. Bandwidth restrictions on the tv broadcasters cause them to have to compress the video feed - hence introducing artifacts, especially where there is a rapid change in the picture (which doesnt have to be motion across a picture. Water (wave motion), for example, can look just as horrible)

Scaling (with a decent scaler) shouldn't add motion blur.

LCD's also have a different problem that is inherent to their technology (ie motion blur) - for more info read -> (Here - and follow the embedded link in the post for a great article)

It is a problem that is seen even on LCD's with very fast refresh rates.

J.

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All,

As I have stated elswhere in this forum, all DVDs both SD and all HD formats are recorded at 24 or 25 frame/s.

AlanH ... to help me understand, does it mean the NTSC sd-dvds are 24/25 frame/sec too?

Thanks.

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Film is 24 frames per second.

PAL DVD’s created from film source are 25 progressive frames per second (with 4% speed up), encoded as 50i (50 fields per second, two fields per progressive frame)

NTSC DVD’s from film source are 24 progressive frames per second encoded as 60i (60 fields per second) with 3:2 pull up to convert the field rate.

Video shot on an interlaced video camera, be it 576i for SD or 1080i for HD, has 50 distinct capture intervals per second and should always be deinterlaced to 576p 50 or 1080p 50.

Only film or other 24fps progressive contend is deinterlaced to 24/25 frames per second.

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As I have stated .... all HD formats are recorded at 24 or 25 frame/s.

Thanks Owen, sorry to be a pest but I really want to get to the bottom of this matter.

According to specs on Toshiba website for hd-dvd player HD-E1:

"HD DVD discs containing high definition content at a field rate of 50Hz or a frame rate of 25Hz cannot be played on HD-E1. Should you have any questions about the frame rate of your disc, please contact the disc vendor".

Does it mean HD-E1 accepts 24Hz discs only, or mean something else?

Thanks.

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Thanks Owen, sorry to be a pest but I really want to get to the bottom of this matter.

According to specs on Toshiba website for hd-dvd player HD-E1:

"HD DVD discs containing high definition content at a field rate of 50Hz or a frame rate of 25Hz cannot be played on HD-E1. Should you have any questions about the frame rate of your disc, please contact the disc vendor".

Does it mean HD-E1 accepts 24Hz discs only, or mean something else?

Thanks.

BluRay supports 1080p 24, 1080i 60, and from memory 1080i 50 as well. Although I doubt there is ever going to be much in that format.

Don’t know about HDDVD.

All players can output 1080p 24 as 1080i 60 to be compatible will all HDTV’s and if the display handles this properly there will be no difference to native 1080p 24 output.

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Firmware upgrade expected apparently, according to a website:

HD DVD discs containing high definition content at a field rate of 50Hz or a frame rate of 25Hz cannot be played on the HD-E1 without a firmware update. Firmware updated is expected in the future. Should you have any questions about the frame rate of your disc please contact the disc vendor.

I think the great majority of HD-DVDs are in 1080p24, which most players output as 1080 p (or i) 60.

This week I ordered an HD-DVD, Van Helsing, via the internet (on Tues morning from EzyDVD Adelaide, by surface post, which arrived at my Brisbane letterbox on Friday). The XPL files on the HD-DVD sure enough state 60 fps.

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...

(ref 1, ref 2 ...)

The research here refers to people sitting at 3 times screen height or 4 times screen height from a 1920x1080 screen and reporting on 720p, 1080i and 1080p material encoded at different bit rates. The conclusion is that 720p is generally to be preferred to 1080i, and 1080p is something to aim for for the future. There was also a finding that 1080p can compress surprisingly efficiently, and perform surprisingly well at lower bitrates.

Whilst I applaud the experimental technique, I have to say that my own observations of free to air 1080i and 720p broadcasts at a viewing distance of 3 times screen height accord with the conventional wisdom that 1080i provides more detail than 720p. HD material broadcast by ABC HD looks much better than SD and is satisfying to watch (broadcast format is 720p), but does lack the extra detail that can be seen on some 9HD and 10HD programs (1080i). My own preference based on FTA reception (in Brisbane) is that I prefer 1080i to 720p.

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The compression of the source video can cause video with fast motion to 'break up', but this is not strictly motion blur (it looks horrible nonetheless). To see this, watch HDTV football during fast pans on a screen not affected by motion blur. Bandwidth restrictions on the tv broadcasters cause them to have to compress the video feed - hence introducing artifacts, especially where there is a rapid change in the picture (which doesnt have to be motion across a picture. Water (wave motion), for example, can look just as horrible)

Scaling (with a decent scaler) shouldn't add motion blur.

LCD's also have a different problem that is inherent to their technology (ie motion blur) - for more info read -> (Here - and follow the embedded link in the post for a great article)

It is a problem that is seen even on LCD's with very fast refresh rates.

J.

Thank you very much for that, Scalpel. That's a pretty amazing article you referenced.

All in all, despite the plasma fanboy's comment just before yours, I consistently prefer the look of the picture on an LCD to a plasma (personal thing, I know) and have been getting way too sensitive to the motion blur issue! If I just relax and stop specifically looking for blur I don't notice a thing and just enjoy the show.

PS3 games look great, broadcast tv looks great (even sport) and I re-watched Casino Royal in Blu-Ray and felt like I was at the cinema. No problems unless you go looking really hard for them.

Looks like I'll have to retract my line about putting the blur in Blu-Ray, but thought it was funny at the time :blink:

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Whilst I applaud the experimental technique, I have to say that my own observations of free to air 1080i and 720p broadcasts at a viewing distance of 3 times screen height accord with the conventional wisdom that 1080i provides more detail than 720p. HD material broadcast by ABC HD looks much better than SD and is satisfying to watch (broadcast format is 720p), but does lack the extra detail that can be seen on some 9HD and 10HD programs (1080i). My own preference based on FTA reception (in Brisbane) is that I prefer 1080i to 720p.

I strongly agree with your observations mate. In my experience with decent bit rate US sourced content; 720p always looks soft compared to 1080 formats. (provided you sit close enough to the screen)

As for 1080i v 1080p, well I have never been able to tell the difference for film source, as one would expect, but true interlaced 1080i 60 from an interlaced video camera has much smoother motion then 1080p 24/25.

I think the conclusions drawn from Ref 1 and 2 may have been flawed by the use of the internal deinterlacer in the Pioneer Plasma used in the evaluation. The use of a small 50” screen is also not helpful.

The use of immature AVC Mpeg4 compression could also be a factor in the perceived poor performance of 1080i. All the content I have compared has been in the mature and well optimized Mpeg2 format. 1080i performs outstandingly well in Mpeg2 with adequate bit rate, were as 720p has always be a great disappointment to me at the same bit rates. In fact I have always had trouble classifying 720p as HD, it’s that soft in comparison to 1080i.

It’s important to note that 24 frame per second film source was not used in the comparison, only 50 frame per second source. So for film source the evaluation is invalid.

It appears that the main thing the observers where looking for with regard to “image quality” where compression artifacts.

With the 3 video formats presented in uncompressed form there was great difficulty in seeing any difference between the three formats, which is very telling in my view.

From what I have seen, Mpeg 4 formats behave poorly with true 1080i content, which confirms the findings of the report, however Mpeg2 in my experience performs dramatically better, but the performance of decent bit rate Mpeg2 was not evaluated.

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Whilst I applaud the experimental technique, I have to say that my own observations of free to air 1080i and 720p broadcasts at a viewing distance of 3 times screen height accord with the conventional wisdom that 1080i provides more detail than 720p. HD material broadcast by ABC HD looks much better than SD and is satisfying to watch (broadcast format is 720p), but does lack the extra detail that can be seen on some 9HD and 10HD programs (1080i). My own preference based on FTA reception (in Brisbane) is that I prefer 1080i to 720p.

I think the conclusions drawn from Ref 1 and 2 may have been flawed by the use of the internal deinterlacer in the Pioneer Plasma used in the evaluation. The use of a small 50†screen is also not helpful.

They chose the 50" screen as representative of enthusiast gear, but given the use of front and rear projectors and the growing availability of 65"+ flat panels, their thinking now looks to have been off the mark. Re the de-interlacer, their damned if they do and their damned if they don't. If they could somehow run a test without any deinterlacing they'd be open to criticisim that it wasn't a representative test as all but the ALiS panels deinterlace ...

The use of immature AVC Mpeg4 compression could also be a factor in the perceived poor performance of 1080i. ...

Very possibly, and they do note that (for 1080p50) they were trying to anticipate hardware encoders of 2-3 years hence.

It’s important to note that 24 frame per second film source was not used in the comparison, only 50 frame per second source. So for film source the evaluation is invalid.

Given that the EBU is looking at this as a "studio" format (i.e. replacing 720p50 & 1080i50 with 1080p50) comparing against film sources is not invalid, it is irrelevant.

With the 3 video formats presented in uncompressed form there was great difficulty in seeing any difference between the three formats, which is very telling in my view.

What is the implication of this however? One could argue that at 3h (1.87m) 720p should be distinguishable from 1080 formats, but as no one (outside of video labs and experimental setups) looks at uncompressed content does this finding actually really tell us anything? Experiences such as MLXXX, yours, and others where you find that "720p has always be a great disappointment to me at the same bit rates" are more telling are they not?

From what I have seen, Mpeg 4 formats behave poorly with true 1080i content, which confirms the findings of the report, however Mpeg2 in my experience performs dramatically better, but the performance of decent bit rate Mpeg2 was not evaluated.

Yes, as I commented earlier, the lack of a comparison with MPEG2 is a decided frustration.

Adrian

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All film or other 24fps source is converted to 25fps for Oz and always has been.

The original source would have been 24fps which can be easily converted for PAL or NTSC markets.

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All film or other 24fps source is converted to 25fps for Oz and always has been.

The original source would have been 24fps which can be easily converted for PAL or NTSC markets.

there are exceptions ....my" ace ventura's 1 and 2" and "nightbreed" but the dvd sleeve clearly lables them "ntsc"

plus the cult zone 1 label "blue underground" directly exports to oz

there probably others

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there are exceptions ....my" ace ventura's 1 and 2" and "nightbreed" but the dvd sleeve clearly lables them "ntsc"

plus the cult zone 1 label "blue underground" directly exports to oz

there probably others

I prefer the sound from NTSC DVDs where the source material is 24fps film. The playback from such DVDs is at the original speed of the performance (correct tempo, pitch and timbre) if your DVD player and TV can handle NTSC.

Of course sport is primarily disseminated by TV, rather by DVDs.

With television, there is a long tradition of running 24fps films at 25fps for compatibility with the PAL 50fps transmission standard in the UK and Australia. And an established practice of creating PAL DVDS from films by speeding up the scanned film by 4.167% for the transfer to PAL.

I am not aware of current Australian studio practice with material arriving from the USA in non-PAL video formats, e.g. 23.976p, 29.970p or 59.940i.

__________________________________________

At the risk of taking this discussion too far off-topic, I thought I'd refer to this webpage as an excellent demonstration of the potential difference in image detail as between PAL DVDs (720x576) and HD-DVDs (1920x1080). The text is in Spanish, but the images speak for themselves. The frames are from one of the Lord of the Rings movies. Click on the DVD button for the (upscaled) DVD version of a cropped section of the original frame, and the HD-DVD button for the HD-DVD version of the cropped section.

Although an example of the 1280x720p format is not shown, it would be intermediate in its image detail.

The relevance of this is to this thread is that when I watch 1080i broadcasts of some tv shows (e.g. House on 10HD) I do see the extra detail compared with 720p, and this is enjoyable and real. It is not something that is merely subtle (on my 60" 1920x1080 SXRD screen).

I guess the obvious point is for someone to come forward and state they prefer the smoothness that 720p [or even 576p] might bring to some sports coverage. And could comment on whether they are aware of (or concerned by) any lack in detail compared with 1080i coverage. How much 720p sport does ABCHD broadcast anyway?

____________________________

Here's another example of differences in detail for different resolution formats. If you click on the image of the frame from I ROBOT, in differing resolution versions, the full size 2.5MB jpeg file can take a little while to load. Scrolling to the left-hand side of the full image, and then scrolling downwards, faciliates the comparison. The detail of the 720p version is a big improvement on the 576p version, and the detail in the 1080p version is somewhat better again.

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there are exceptions ....my" ace ventura's 1 and 2" and "nightbreed" but the dvd sleeve clearly lables them "ntsc"

plus the cult zone 1 label "blue underground" directly exports to oz

there probably others

Obviously if it says NTSC on the label it’s not a PAL DVD intended for Oz.

Anyone can import NTSC DVD’s but that not the point

All DVD’s intended for Australia are labelled PAL, and if region coded are region 4.

Film sourced content will be encoded at 25fps on PAL DVD’s.

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This is one reason I prefer the sound from NTSC DVDs where the source material is 24fps film. The playback from such DVDs is at the original speed of the performance (correct tempo, pitch and timbre) if your DVD player and TV can handle NTSC.

Of course sport is primarily disseminated by TV, rather by DVDs.

With television, there is a long tradition of running 24fps films at 25fps for compatibility with the PAL 50fps transmission standard in the UK and Australia. And an established practice of creating PAL DVDS from films by speeding up the scanned film by 4.167% for the transfer to PAL.

I am not aware of current Australian studio practice with material arriving from the USA in non-PAL video formats, e.g. 23.976p, 29.970p or 59.940i.

mate...dont talk about pal and ntsc

i love cult movies

so[the movies] not being part of the major studio out-put i have hunt all around the world for the best copy

a dozen different companies may put out the same flick...so i got to do my homework and find the best one with concerns about ..16/9...uncut...muliple audio ....flagged for progressive...subjective choices on masteringetc...etc

so my dvds may come from any dvd zone in any format[zone 2 has japan and england thus has ntsc and pal....go figure]

thats ok .....but my dvd player doesnt auto select format....so got read the dvd cover ...find the format ...then configure the player....WHAT A HASSLE

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Obviously if it says NTSC on the label it’s not a PAL DVD intended for Oz.

Anyone can import NTSC DVD’s but that not the point

All DVD’s intended for Australia are labelled PAL, and if region coded are region 4.

Film sourced content will be encoded at 25fps on PAL DVD’s.

no there not...and i just told u some exceptions !

go to jb's and have a look at "ace ventura" dvd

labeled "region 4" and "ntsc"

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no there not...and i just told u some exceptions !

go to jb's and have a look at "ace ventura" dvd

labeled "region 4" and "ntsc"

Some people in Oz have dvd players and tvs that can handle NTSC, but the Australian standard is PAL, and that is what is used for television broadcasts in Australia.

Although the sound is usually better from an NTSC dvd (because it is usually at the true speed of the performance), the vertical resolution may be inferior as the format is usually 720x480 rather than the PAL standard of 720x576. And the 3:2 pulldown process in the NTSC compatible DVD player that converts the 24fps film frames to 60fps NTSC [59.94i] for the NTSC compatible TV, can introduce judder during panning.

I don't know whether an Australian tv station would ever try to broadcast content from an NTSC dvd but if they did try, there would be conversion issues.

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no there not...and i just told u some exceptions !

go to jb's and have a look at "ace ventura" dvd

labeled "region 4" and "ntsc"

Region 4 encompasses South America and Mexico, both NTSC areas, so region 4 DVD’s can be NTSC, however Australia and New Zealand are PAL ONLY.

If you get an NTSC DVD here it is an import NOT intended for the Australian market.

Most modern TV’s are multi standard, so NTSC DVD’s will display on them, but older TV’s are often PAL only and are not NTSC compatible.

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Some people in Oz have dvd players and tvs that can handle NTSC, but the Australian standard is PAL, and that is what is used for television broadcasts in Australia.

Although the sound is usually better from an NTSC dvd (because it is usually at the true speed of the performance), the vertical resolution may be inferior as the format is usually 720x480 rather than the PAL standard of 720x576. And the 3:2 pulldown process in the NTSC compatible DVD player that converts the 24fps film frames to 60fps NTSC [59.94i] for the NTSC compatible TV, can introduce judder during panning.

I don't know whether an Australian tv station would ever try to broadcast content from an NTSC dvd but if they did try, there would be conversion issues.

im not disputing anything u say

im just saying ntsc disc's are sold as region 4 in oz

the people bringing them in are probably tight-arses and dont want to pay for the conversion

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At the risk of taking this discussion too far off-topic, I thought I'd refer to this webpage as an excellent demonstration of the potential difference in image detail as between PAL DVDs (720x576) and HD-DVDs (1920x1080).

I don't think there is any debate that 1080p24 is better than 720p24 which is better than 576p24.

Likewise, 1080p50 is better than 1080i25 ("i25" seems to be used in different ways on different websites... I mean that both refresh 50 times a second, but the "i25" only does every 2nd line during each refresh). Obviously the i25 is half the data so much smaller transmission!.

I'd like to summarise my understanding of the debate... someone will tell me if /where I've misunderstood.

The debate starts when you compare 1080p25 with 1080i25. The interlaced refreshes 50 times a second, but only half the lines, while the progressive refreshes 25 times a second but all the lines. Then we get more confusing by adding 720p50 into the equation.

It seems the most vocal in this thread say that 1080i25 is better because there are 50 new pictures a second. Even though it's interlaced, they say a good deinterlacer can effectively compensate for missing lines (the latest developments doing particularly good jobs).

Thus, they say, 1080i25 looks pretty close to 1080p50. Hence 1080i25 is better than 1080p25

Back to the beginning - we know 1080p50 is better than 720p50.

But what about 1080i25? Does it REALLY look like 1080p50? or because of the approximations, does 720p50 look better?

Note that although deinterlacers are getting better and better, for the really fast motion stuff they still simplify the picture to 540 lines...

I think the answer is that IF you have a 1080p screen, and the latest & best deinterlacers, then 1080i is best ... since it will still downgrade to half resolution when it's moving fast, but we can't notice it because it's moving fast (and when it slows down it gives the full resolution).

... If you have a 768line screen then 720p will be better - but if you're watching 1080i then make sure you have a good deinterlacer.

So guys... I don't want you to rehash what you've said... but is that a fair summary?

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