Originally Posted by Ungermann
You should have said "25PsF" right from the start ;-)
It makes deinterlacer's job oh so much easier. Seriously, BBC could have chosen either 720p50 to save bitrate and prevent image from breaking down, or maybe even 1080p50 @ 16 Mbit/s.
1080p50 isn't supported in any of the standard DVB profiles yet is it? If they had gone for 1080p50 they'd have had to create a new standard - and production at 1080p50 is still marginal (and thus expensive). The driving force for the 3G infrastructure required is 3D 1080/50i - not 2D 50p...
The arguments about 720p50 vs 1080i25 (aka 50i) have been done to death. The UK has gone 1080i25 - Sky, the BBC, C4, ITV - industry wide. All the major international sporting events are 1080i.
Other European countries - Scandinavia, Germany - have gone 720p50.
With AVC encoding being twice more effective, as they claim, why not? I encoded 1080p60 @ 18 Mbit/s myself from the Panasonic TM700 camcorder, and it looks great.
Yep - but 1080p50 and 1080p60 are unsupported profiles in the DVB specs - so weren't (and still aren't) options for broadcast.
Instead, they decided to stick to stupid 1080i with 1440 pixels across and lower-than 10 Mbit/s bitrate. Where is progress in that?
The 1440 is entirely pragmatic. HD Cam and DVC Pro HD are the two most widespread acquisition standards. Both subsample to 1440 at acquisition - there is no >1440 horizontal resolution.
Sure - live content and some high-end stuff mastered to HD Cam SR has horizontal content >1440 - but this is not the bulk of output - and 1440 is still a lot better than the 1280 of 720p.
I'm not getting into the bitrate discussion - but H264 encoding has got a LOT better since 2006 when the original DVB-T and DVB-S BBC HD trials ran - and were delivering poorer picture quality at 18Mbs than we now get at 10Mbs.
No, 1080p25 is not natively supported, thanks to Sony, it screwed everybody once again.
Thought I hadn't got that wrong... Very US movie-studio centric stance.
With 1080PsF25 you are at the mercy of deinterlacer. 720p50 with frame repeat is more compatible and reliable, I think.
Yep - but you then lose a huge amount of horizontal resolution, some vertical resolution and don't get the benefits of improved temporal resolution.
De-interlacers are getting better as well... Though not universally.
Top Gear is 25PsF for featured segments, and true 50i for studio stuff.
Yep - a choice I like. A 25PsF studio always looks wrong and never feels live. The track sequences are also 50i and feel right. The films look beautifully filmic - the contrast works well.
My software player is not smart enough to switch from interlaced to progressive, so I switch it manually. My set-top media player cannot handle PsF at all. So many problems because of freaking interlace. BBC could be a pioneer, instead it drops bitrate and packages "film look" into interlace feed. Pitiful.
My PC de-interlaces using vector adaptive pretty well, as does my DVB-S2 satellite receiver. No nasty indecision between crude bob and weave.
Back to the thread: I got a 720p25 encode of Sherlock, looks nice and clean on my 60Hz TV, no ghosting or combing except for the credits, but who cares about them. I watched the first episode so far, looks nice. Different from what I used to.
The 1080i25 (aka 50i) Blu-ray looks cracking - 30+Mbs. (DTS HD HR not MA audio I think - but around 2Mbs)