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576p is not HD

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Most American primetime shows transmitted in 1080i can be viewed in 1080p@25hz w/out interlacing artifacts. I think the only way you can view it this way is through a computer though.

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Most American primetime shows transmitted in 1080i can be viewed in 1080p@25hz w/out interlacing artifacts. I think the only way you can view it this way is through a computer though.

That's because they are shot on film. Same with most movies shown here...looks damn good too.

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DLP, LCD and plasma convert to progressive (apart, perhaps from the pseuo-interlace plasma, whatever its called - name slipped my memory)

What method do they use: weave, bob or motion adaptive? Am I right that in most cases an external deinterlacer in the source or video processor will usually do a better job

Those outputs are supported currently, btw {1080i, 720p and 576i}!

1080 24p is not supported, and as most movies are shot on film, this will be the format used, so how will current displays support it?

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Most American primetime shows transmitted in 1080i can be viewed in 1080p@25hz w/out interlacing artifacts. I think the only way you can view it this way is through a computer though.

That's because they are shot on film. Same with most movies shown here...looks damn good too.

Yup, either film or a digital video camera capable of doing 24/25p (I think The 4400 was done this way?).

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Yup, either film or a digital video camera capable of doing 24/25p (I think The 4400 was done this way?).

Not sure about The 4400 (IMDB doesn't have any tech specs), but this is definitely the right way to do 1080@50i - it is then capable of being 'cleanly' deinterlaced for progressive display, and 'degrades' gracefully to 1080@50p (albeit at half the possible frame rate).

- Miles.

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if you haven't opened them up yet, they're animated gif's set to alternate between the two every half a second or so

the one with the high definition logo on the bottom right corner of each shot is the one that's high definition (sorry.. "enhanced definition" as they say in this forum)

and the one without the logo is the dvd

i got lazy and couldn't be bothered labelling each screenshot with either a HDTV or DVD logo for 8 different shots

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Interesting, the ED channels are clearly higher in definition. I wonder if ED really is that much better or it was crappy dvd mastering. One presumes they would have ot master it again especially for the HD broadcast. Another problem is that many DVD's are reencoded from the 480p US dvd's. So try do this again, comparing 7's SD and HD transmission. :blink:

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right, anyone have the SD transmission of this? so we can compare? cuz i only record the HD channels, using DVR-MS (not enough hdd space for full .ts)

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Yup, either film or a digital video camera capable of doing 24/25p (I think The 4400 was done this way?).

Not sure about The 4400 (IMDB doesn't have any tech specs), but this is definitely the right way to do 1080@50i - it is then capable of being 'cleanly' deinterlaced for progressive display, and 'degrades' gracefully to 1080@50p (albeit at half the possible frame rate).

- Miles.

The process used by 1080i video cameras to record 1080 25P is called 'progressive segmented frame' (psf). The camera captures the whole image off the CCD each 25th of a second, although, usually, an electronic shutter limits the capture time to a 50th, to reduce blur. The resulting image is split into two fields and recorded as interlace, i.e. 1080i.

I think the 4400 was shot on video using 24p, (i.e. 29.97 psf, a sort of reverse video 3:2 pulldown).

Some one will correct me if I'm wrong here, but I think most progressive displays don't deinterlace 1080i to scale it. They simply treat each field as a progressive frame and scale the 540 lines to the display res.

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When next generation DVD movies are released on Blu-Ray/HD-DVD, they will most likely be in the format 1080p24 (or 1080sf24 I am not exactly sure what this format is), will current displays be able to accept this input or will players have to convert to say 720p or 1080i (can players interlace a progressive format?)

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When next generation DVD movies are released on Blu-Ray/HD-DVD, they will most likely be in the format 1080p24 (or 1080sf24 I am not exactly sure what this format is), will current displays be able to accept this input or will players have to convert to say 720p or 1080i (can players interlace a progressive format?)

I doubt they will be 24p. The 108024p or 24sf is really only a post production foemat. The comsumer realease will start with 108050i and as someone pointd out if the content was shot in a 'p' mode then the display would be a 'p' display, the only think being the 2 fields have the same image, but are presented in a time offset. Some displays will de-interlace etc.

Down the track there may be 24/25p discs but not for a while. When you see a 'PR' like "Presented in 24p", the cameras will in 'p' mode but the transmission has to converted back to interlace mode, with fields that are indentical.

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This is straight from my Terminator 2 Extreme DVD "Manual"

The previous transfer of T2 (the version that appeared on T2 The Ultimate Edition DVD) was created at the highest quality available at that time. However, since that time, many improvements have taken place in the realm of film-to-video transfers (also known as telecine).

Upon evaluation of the 1997 master elements, THX and Artisan determined that the picture quality and format of the high-definition (HD) images might not meet today's standards for HD distribution in the future. While video processing on this older master could have created a good quality image for DVD, time and effort would be spent on a master that had little future. THX is proud to take part in Artisan's decision to retransfer T2 using the latest telecine and post production technologies. This new film transfer has resulted in the superior images you will find on this DVD release.

Starting from the same interpositive (IP) print created from the original negative of the film used in 1997, THX supervised the transfer of the film into HD video. This new HD master could be called an "electronic film master" since it is an exact representation of the film recorded onto HD-D5 videotapes. The transfer and subsequent mastering were performed at International Video Conversions (IVC) in Burbank, California.

The technical format for the T2 electronic film master is 1920x1080 24PsF. Here is a brief explanation of what that means. 1920x1080 is the size of each video frame and is the current standard resolution of HD video. Each frame of the film is scanned into a frame of video that is 1,920 pixels wide and 1,080 lines high. Doing some math reveals that a picture size of 1920x1080 has an aspect ratio of 1.78:1 (1920 / 1080) which means that the width of the picture is 1.78 times the height of the picture. 1.78:1 is also known by the term 16x9 because 16/9 also equals 1.78.

Any movie that has an aspect ratio of 1.78:1 would fill a 1920x1080 frame size perfectly. However, T2 was released in an aspect ratio of 2.35:1 which means that the width of the picture is 2.35 times the height of the picture. Movies that have an aspect ratio larger than 1.78 would have to have black mattes (also known as letterboxing) added to the top and bottom portions of the screen in order to fit the enire width of the wider film frame into a 1.78:1 picture.

Because of letterboxing, in a frame size of 1920x1080, a 2.35:1 picture would have used the entire resolution width of 1,920 pixels, but would only use approximately 815 lines of the 1,080 available lines. The rest of the 265 lines would be used and wasted by the black mattes. A decision was made early to optimize the new master by transferring the movie FULL FRAME by scanning each film frame so that it filled the entire 1920x1080 area, thus increasing the resolution of the image. While this master is not formatted properly, it utilises every single line for the actual picture content and maximises the ability to perform needed restoration.

24PsF (or Progressive Segmented Frames) describes two things: the frame rate and how the picture was created. The number "24" means that the electronic film master plays back at 24 frames-per-second, just like film. In fact, the electronic film master matches the film, frame for frame--one frame of film equals one frame of video.

"Progressive Segmented Frames" means that each frame of video is created progressively , just like film. In order to understand what progressive means, here are the differences between the two ways of creating video frames: progressive and interlaced. The majority of standard definition consumer televisions create frames of video using interlacing, while many HD consumer televisions are capapble of creating video progressively.

With interlaced scanning the video frame is scanned as two seperate fields, thus:

* Top field (odd scan lines) scan line numbers 1, 3, 5, 7, 9, 11, etc. followed by

* Bottom field (even scan lines) scan line numbers 2, 4, 6, 8, 10, 12, etc.

* The video frame does not always capture the exact same content that a film frame contains

* Motion does not appear as smooth; diagonal lines are jagged

With progressive scanning the video frame is scanned in one complete pass thus:

* The complete video frame as: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

* The video frame caputres the exact same content that a film frame contains at any instance in time

* Motion is smoother; diagonal lines are smooth

* Video frames are easier to work with since they are complete frames and no parts of frames

you can find out more details at http://www.thx.com/T2

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Thanks Davo, so why wouldn't the film studios produce their new Blu-Ray/HD-DVD HD film transfers in 1920x1080 24PsF?

24PsF is only used in telecine and production. The reason it's called PsF rather than just PF (progressive frame) is because it is 'segmented', i.e. a single progressive frame is divided into two fields for recording. The purpose of PsF is to allow the use of facilities designed for interlace to be used for low frame rate (i.e. 24 or 25 fps) progressive. It's also a way for Sony to flog their ageing 1080i HD system to the film industry, rather than develop a proper progressive HD System. Ultimately films will be shot on super high resolution true progressive systems.

When a DVD is made the HD master is converted to either 480i or 576i. For NTSC systems that means a conversion to 30fps, i.e. 3:2 pulldown. For us it means speeding things up by 1 fps to 25fps. A PAL DVD is effectively 576 25PsF.

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