720p better than 1080i

Robbie G said:
Probably end up being a total anticlimax
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Well, I was right. The box hasn't been matched in Virgin's inventory, i.e. it apparently somehow got through their system without the serial number being logged. Accordingly it is currently a brick, at least until someone at VM adds the serial number to the inventory (24 hrs apparently).

I'm not the world's most patient guy and this is like that feeling you get when you receive a new graphics card or monitor, switch it on, and it's b0rked. Ho hum!
 
Just had a call from VM. The box they sent me was designed to work in a different area (apparently batches of serial numbers are locked to certain regions). They're sending me another out tomorrow. Had better be another Samsung version!
 
Robbie G said:
Had better be another Samsung version!
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If it's a SA box, just ring them after a few days and say it's crashing a lot and is slow (it actually is slow and will crash a lot anyway). They should replace it with a Samsung box.

The amount of times our SA box crashed in a day was unreal. Surely they must have tested the boxes before rolling them out, and known exactly how **** they are. :p
 
asim18 said:
If it's a SA box, just ring them after a few days and say it's crashing a lot and is slow (it actually is slow and will crash a lot anyway). They should replace it with a Samsung box.

The amount of times our SA box crashed in a day was unreal. Surely they must have tested the boxes before rolling them out, and known exactly how **** they are. :p
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Knowing and caring are two different things :D.

Will certainly consider pestering their faults department if I get a SA box though. The other problem with the SA boxes is that the menus aren't sharp in 1080i mode.
 
Demon said:
Since video is shot at only 30fps, technically you aren't losing any information at all, you are getting 1920*1080 resolution at the same frame rate as it was recorded..

720p60 is irrelevant, since the video was still only shot at 30Hz (Max)...
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Sorry mate but thats BS there are broadcast cameras that shoot at 1080p 50/60 and 720p 50/60

Progressive is always relevant.
 
Phil2008 said:
Ah, dont decent tv's do that with fast moving objects on 1080i?
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I've been running our V+ HD box in 1080i since day 1, (been about a year now). Never had any of the issues that man described in the video, and it looks noticeably better than 720p.

I'm 100% sure. Even watching snooker on Eurosport HD, absolutely perfect.

What that man is doing is playing back 1080i content without any de-interlacing. This is a stupid thing to do and there will obviously be artifacts. I don't think he mentioned de-interlacing a single time, which makes me think he's a troll who just doesn't like interlacing for some weird personal reason and wants other's to hate interlacing as well.

And just FYI; DVD Video, the biggest and most popular form of video distribution for over a decade, IS INTERLACED VIDEO!!!

We have a 1080p Samsung LE46M87/BDX btw, bought it from OcUK about 4 years ago!.
 
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No, the guy in the video is right in that interlaced video will display the comb effect artifacts while playing fast motion footage. He seems to talking about interlaced video that is 50/60 fields per second (raw footage from cameras mostly) where the comb effect will be more visible. What is probably broadcast over the majority of stations these days is 25/30 frames per second that's converted to 50/60 fields per second meaning that the fields are simply duplicated. Live news is usually still broadcast interlaced these days and if you're TV/set-top box displays it correctly you'll notice the motion is a lot more fluid and the comb effect more noticeable. If they don't then it'll just be de-interlaced (combining one odd and even field to make a complete frame) to display at 25/30 frames per second.
 
Rozzy85 said:
No, the guy in the video is right in that interlaced video will display the comb effect artifacts while playing fast motion footage.
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Only if you're doing it wrong. :)

I'd say a snooker ball is very fast moving, so why didn't I see a single comb artifact during the whole World Championship on Eurosport HD?

I'd say Top Gear is very fast moving, so why haven't I seen a single comb artifact on BBC HD?

The answer is, the TV is recognising that it's an interlaced signal coming from the V+HD box, and is displaying it properly.

If you play an interlaced file over a progressive signal (eg. A monitor connected to pc) then you will need to enable software de-interlacing in the video player. This is because the monitor/TV wont know the file is interlaced, due to the fact that the signal it is receiving is progressive. This is when you will get artifacts.
 
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asim18 said:
Only if you're doing it wrong. :)

I'd say a snooker ball is very fast moving, so why didn't I see a single comb artifact during the whole World Championship on Eurosport HD?

I'd say Top Gear is very fast moving, so why haven't I seen a single comb artifact on BBC HD?

The answer is, the TV is recognising that it's an interlaced signal coming from the V+HD box, and is displaying it properly.

If you play an interlaced file over a progressive signal (eg. A monitor connected to pc) then you will need to enable software de-interlacing in the video player. This is because the monitor/TV wont know the file is interlaced, due to the fact that the signal it is receiving is progressive. This is when you will get artifacts.
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This is largely true..

I was corrected earlier in the thread about source material being available in 50/60Hz formats, but the essence of all this is that no matter what, all material is re-encoded to 1080p25 or 1080i25 and that's what's presented to the various platform set top boxes.. As long as your TV can correctly de-interlace, you will get no combing artefacts (unless they are encoded at source, which may happen in some old stuff, but I would say it's quite rare)..
So in reality, if any set top box has 720p or 1080i options only, then for a Full HD set, you really should use 1080i unless you have a gimped TV.. If you have a non Full HD set, then it's going to be a case of suck it and see, either the Set top box will have to de-interlace then down sample to 720p, and all the TV has to do is resample to it's native resolution, or feed 1080i straight to the TV, see if that's better at de-interlacing and scaling..

That youtube video is out of date for the UK at least, all delivery methods use 1080i25 at worse, which by it's definition won't ever give combing artefacts with simple de-interlacing.
 
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Largely true, but poor deinterlacers will often display similar artifacts on very fast moving stuff, e.g. your snooker ball example. There are two main ways of deinterlacing, bob and weave, with several other fancy methods that are largely combinations of the two depending on motion. Bob will give you an unstable picture but very good motion and no combing, whilst weave is the opposite. Many TVs are now so good at deinterlacing that you won't notice either issue, but many older sets don't do a great job. Remember, setting your box to 720p doesn't give you a 720p feed, it just does the deinterlacing on the box and sends the resulting signal progressively. If you've got a 1080p TV though you'll get the box deinterlacing and scaling, which is generally a bad idea on cheap hardware. If you've a 1080p set let the TV do the work.

Interlacing is still done for broadcasts because it's half the bandwidth, but if you watch something like the still shots of food on masterchef you'll struggle to notice the difference between 1080i and 1080p. If there's a lot of motion you're actually at 1080 /2, (i.e. < 720) and so 720p is the better option, but remember - the feed is still 1080i, so setting the box to 720p doesn't give a 'better' result, just a different one :)
 
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