Why Top Gear reports look bad on DVDO Edge

[jgrg]

I think I've worked out why, in contrast to their studio footage, which looks OK, field reports on Top Gear look bad. I recorded a clip and looked at it on my Mac. The video player doesn't, as far as I can tell, do any de-interlacing. The studio footage showed the combing you expect from interlaced video. There is, however, no combing in the reports, which look pixelated, with jagged edges. Using Apple's Pixie tool to look at the pixels in detail I can see that it looks like the report video has been de-interlaced by line doubling of fields. So to the Edge it is progressive, and it looks particularly bad when it blows this up to 1080p to fit my screen since the scaling algorithm makes the jagged edges of diagonals more pointy.

I attach two enlargements from my clip. The first are the hands of someone in the studio audience clapping, so you can clearly see the combing. The other is from a report, and is the edge of a box in the back of a veteran car from a static shot, where you can very clearly see the line doubling.

[eiren]

I get this in the Snuff Box DVD (also from the BBC Snuff Box: Michael Cumming: Amazon.co.uk: DVD)

Basically it's originally recorded as video and then it's converted to give it a film-like look (as per Top Gear) so they deinterlaced it and just used every other frame. As such, the deinterlacing used to do this was of poor quality and resulted in the jaggies you see on most diagonal edges.

What worked to get rid of it was to switch EDGE over into Game mode, and that overrode the problem. This forces the EDGE to construct each output frame from only a single input field using its deinterlacer's diagonal processing. The downside to this is that you may lose a little detail (or not, depending on how the original deinterlacing was done) and it will introduce some flicker into the image. It will get rid of the jaggies, however.

OR you can just put it down to botched source material.

[petes]

Originally Posted by jgrg

I think I've worked out why, in contrast to their studio footage, which looks OK, field reports on Top Gear look bad. I recorded a clip and looked at it on my Mac. The video player doesn't, as far as I can tell, do any de-interlacing. The studio footage showed the combing you expect from interlaced video. There is, however, no combing in the reports, which look pixelated, with jagged edges. Using Apple's Pixie tool to look at the pixels in detail I can see that it looks like the report video has been de-interlaced by line doubling of fields. So to the Edge it is progressive, and it looks particularly bad when it blows this up to 1080p to fit my screen since the scaling algorithm makes the jagged edges of diagonals more pointy.

I attach two enlargements from my clip. The first are the hands of someone in the studio audience clapping, so you can clearly see the combing. The other is from a report, and is the edge of a box in the back of a veteran car from a static shot, where you can very clearly see the line doubling.

In general, Top Gear just looks horrible whatever you do to it - which is pity. Once you've seen it, you want to look at the lovely automobilia (if such a word exists), but can't help looking at the horrible stepping in the image of the A-pillar on that Veyron - grrrrr

[mackie1]

I noticed this with Clarkson's Thriller DVD. I guess they use the same production method for these DVDs. I was a little worried by it as it was the first DVD I tried in my new Oppo DVD player and it looked somewhat crap!

[Liam @ Prog AV]

Why oh why are Top Gear still filming in SD?? The Polar Expedition one (which was shown in HD) had some truly amazing footage - with all these sexy cars and cool camera shots surely it needs to be done in HD.

[jgrg]

Originally Posted by eiren

What worked to get rid of it was to switch EDGE over into Game mode, and that overrode the problem. This forces the EDGE to construct each output frame from only a single input field using its deinterlacer's diagonal processing. The downside to this is that you may lose a little detail (or not, depending on how the original deinterlacing was done) and it will introduce some flicker into the image. It will get rid of the jaggies, however.

That's a great tip, thanks. My work around had been to put my satellite receiver into 1080i, but the Edge in Game Mode looks better. Have just ordered a universal remote, so I should be able to use the discrete codes for Game mode on/off instead of hunting through several layers of menus.

Also sent a feature request to DVDO to add a "force video mode" option to the Edge.

[jgrg]

Originally Posted by Liam @ Prog AV

Why oh why are Top Gear still filming in SD?? The Polar Expedition one (which was shown in HD) had some truly amazing footage - with all these sexy cars and cool camera shots surely it needs to be done in HD.

Yes, since Top Gear is one of the BBC's most popular shows, surely it will be near the top of the list for HD production.

I don't understand why these shows can't shoot in progressive SD video. Would double the vertical resolution compared to how they are currently doing it. Maybe such cameras don't exist?

[Barcoing Mad]

I suspect that the Top Gear production team are the most stupid.............in the world.

[jgrg]

Originally Posted by Barcoing Mad

I suspect that the Top Gear production team are the most stupid.............in the world.

They're not the only offenders. I've seen the same thing with Five's Gadget Show reports, and the Holby City Christmas special (might also apply to all of their other episodes, but I don't watch it). I wonder if it is the same production company?

[NicolasB]

Originally Posted by jgrg

I don't understand why these shows can't shoot in progressive SD video. Would double the vertical resolution compared to how they are currently doing it. Maybe such cameras don't exist?

Maybe they feel that the higher frame rate (and consequent improvements to smooth motion) are worth the loss of vertical resolution? It's by no means guaranteed that 576p/25 will look better than 576i/50.

Using an interlaced source doesn't usually halve the vertical resolution, anyway. You only drop all the way to half-res if every pixel in the frame is in motion (e.g. if the camera is panning). If part of the picture is the same as it was one frame ago then (assuming correct deinterlacing) you get the same resolution within that portion of the picture as you would with a progressive source.

[jgrg]

Originally Posted by NicolasB

Maybe they feel that the higher frame rate (and consequent improvements to smooth motion) are worth the loss of vertical resolution? It's by no means guaranteed that 576p/25 will look better than 576i/50.

Using an interlaced source doesn't usually halve the vertical resolution, anyway. You only drop all the way to half-res if every pixel in the frame is in motion (e.g. if the camera is panning). If part of the picture is the same as it was one frame ago then (assuming correct deinterlacing) you get the same resolution within that portion of the picture as you would with a progressive source.

Yes, sure. Was just thinking that in the case of this botched footage, where they clearly want the "film look", why not shoot progressive instead of discarding half the fields to make rubbish line doubled progressive from interlaced video?

[jgrg]

Originally Posted by jgrg

They're not the only offenders. I've seen the same thing with Five's Gadget Show reports, and the Holby City Christmas special (might also apply to all of their other episodes, but I don't watch it). I wonder if it is the same production company?

Yes, Holby City, on now, is the same. Very nasty.

[Barcoing Mad]

James and Oz boozing around Britain last night...very, very nasty both over HDMI (576p) and with interlaced RGB over scart in a C2. No-one should be blaming their VPs.

[eiren]

Channels seem to show things slightly different too. Although I am not a fan, when Neighbours was shifted from the BBC to Channel 5... it seems to have been converted from video to that film-esque look by Channel 5.

The same happened when they shifted Home & Away over from ITV.

I'm quite ashamed to admit to have noticed this

[kingfats]

Originally Posted by eiren

Channels seem to show things slightly different too. Although I am not a fan, when Neighbours was shifted from the BBC to Channel 5... it seems to have been converted from video to that film-esque look by Channel 5.

The same happened when they shifted Home & Away over from ITV.

I'm quite ashamed to admit to have noticed this

I noticed that as well,my wife watches it though not me.