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Old 10-23-2006, 12:47 PM
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Default Blu-ray format question

If anyone here knows anything about the specific details on blu-ray, can you answer this question:

On DVD's even if a movie was 2.39:1 it still used the entire 720x480 and filled in the rest with black pixels. Does blu-ray do the same thing? i.e. fill 1920x800 with video and the rest with black pixels, or only have a 1920x800 video file? If it was only a 1920x800 video file, it would be able to use a lot of bits more efficiently to distribute them through the movie, and not just through black space. Or, even better, if the entire 1920x1080 was filled with video, then scaled back to 1920x800 when playing back on a HDTV, While PC's supporting 2584x1080+ or future TVs could play these movies at higher resolution than standard 1080p HD.
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Old 10-25-2006, 04:21 AM
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okay here it goes, ever since dvds, they have always shown a full 480i/p resolution when in widescreen, vhs on the other hand used part of its resolution for the black bars when they made a letterbox movie. Blu-ray/HD-DVD do the same thing as DVD, the 1080p is the full resolution of the picture that you see. Think of it like this, all the video is what you see without the bars, when looking at a 2:40:1 movie the black bars are being added in by the player (not necessarily true but its a good way to think of it) basically to answer your question, unless the newer resolution tvs 1440p or higher have a good scaler, you are not really going to get a better picture with a 1080p source. I hope that answers your question.
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Old 10-25-2006, 02:26 PM
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okay here it goes, ever since dvds, they have always shown a full 480i/p resolution when in widescreen, vhs on the other hand used part of its resolution for the black bars when they made a letterbox movie. Blu-ray/HD-DVD do the same thing as DVD, the 1080p is the full resolution of the picture that you see. Think of it like this, all the video is what you see without the bars, when looking at a 2:40:1 movie the black bars are being added in by the player (not necessarily true but its a good way to think of it) basically to answer your question, unless the newer resolution tvs 1440p or higher have a good scaler, you are not really going to get a better picture with a 1080p source. I hope that answers your question.
I understand that for the most part, but the black bars for 2.4:1 movies on DVD were added in the file, not by the player, as the file was 720x480, not 720x360. 720x360 would preserve the aspect ratio, as well as using more bits towards the movie instead of towards black bars. Another Idea, since DVDs 720x480 is not a 1:1 pixel aspect, DVD already use scaling for widescreen. Another thought I was having was to take that whole 720x480 picture, fill it all with stretched video to fit the entire frame in without black bars, then scale it out on HDTVs and PCs at 1144x480, and have a better picture than 2.4 movies playing at approximately 856x360.

Now I thought this idea would work well with blu-ray because instead of a movie being played at 1920x800 (which is what it sounds like it does, putting the 1920x800 video in a 1920x1080 video file, putting black bars in the file.) The movie file would be 1920x1080 (full movie picture stretched) then, when it is played on future equipment, such as 1440p or 2160p , or future PC monitors, that video would then be played at 2584x1080 instead of 1920x800. Do you understand my point?

Basically I'm saying put the full resolution of the blu-ray (1920x1080) to use instead of wasting part of it with black bars, using up bits, as it will look better in future equipment. Either that or just use a resolution of 1920x800 and allow more bits to be used on the movie instead of black bars.
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Old 10-25-2006, 11:40 PM
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Originally Posted by morphinapg View Post
I understand that for the most part, but the black bars for 2.4:1 movies on DVD were added in the file, not by the player, as the file was 720x480, not 720x360. 720x360 would preserve the aspect ratio, as well as using more bits towards the movie instead of towards black bars. Another Idea, since DVDs 720x480 is not a 1:1 pixel aspect, DVD already use scaling for widescreen. Another thought I was having was to take that whole 720x480 picture, fill it all with stretched video to fit the entire frame in without black bars, then scale it out on HDTVs and PCs at 1144x480, and have a better picture than 2.4 movies playing at approximately 856x360.

Now I thought this idea would work well with blu-ray because instead of a movie being played at 1920x800 (which is what it sounds like it does, putting the 1920x800 video in a 1920x1080 video file, putting black bars in the file.) The movie file would be 1920x1080 (full movie picture stretched) then, when it is played on future equipment, such as 1440p or 2160p , or future PC monitors, that video would then be played at 2584x1080 instead of 1920x800. Do you understand my point?

Basically I'm saying put the full resolution of the blu-ray (1920x1080) to use instead of wasting part of it with black bars, using up bits, as it will look better in future equipment. Either that or just use a resolution of 1920x800 and allow more bits to be used on the movie instead of black bars.
Unfortunately, the black bars you see on a 2.35:1 or 2.40:1 movie, as well as pillarbox bars are actually part of the encode. The upside of this is since there is no motion in the black bars, they hardly take up any space in the bandwidth. I have heard that there is an anamorphic spec for either Blu-ray or HD DVD, but it is not enabled at this point, and I don't know if is mandatory in the current players, but I doubt it, as there are no setting preferences to indicate that.

I do know that the first HD-shot movies (Star Wars, Episode II; Once Upon a Time in Mexico; etc.) were actually shot full-frame, and then cropped with letterbox to arrive at a 2.35:1 picture. I was surprised to learn this at first, especially to see it happening in the Lucasfilm camp. Movies shot on the Viper, however, (Collateral, Miami Vice), I believe may have actually been anamorphically squeezed to allow all the picture information to fill the cinemascope aspect ratio.
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Old 10-25-2006, 11:57 PM
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Unfortunately, the black bars you see on a 2.35:1 or 2.40:1 movie, as well as pillarbox bars are actually part of the encode. The upside of this is since there is no motion in the black bars, they hardly take up any space in the bandwidth. I have heard that there is an anamorphic spec for either Blu-ray or HD DVD, but it is not enabled at this point, and I don't know if is mandatory in the current players, but I doubt it, as there are no setting preferences to indicate that.

I do know that the first HD-shot movies (Star Wars, Episode II; Once Upon a Time in Mexico; etc.) were actually shot full-frame, and then cropped with letterbox to arrive at a 2.35:1 picture. I was surprised to learn this at first, especially to see it happening in the Lucasfilm camp. Movies shot on the Viper, however, (Collateral, Miami Vice), I believe may have actually been anamorphically squeezed to allow all the picture information to fill the cinemascope aspect ratio.
There was a sort of anamorphic setting in DVD at 2.11:1 or something like that, but it was never used. And that bit about black bars not takign much space is only if the most effectively use the codec, but by some of the reviews I have heard, some early blu-rays may not be using the codecs the best. When I used my MPEG2 codec properly, I could get good quality at 2-3 mbps, whereas most people recommend 6-9 mbps for good quality.

Last edited by morphinapg; 10-26-2006 at 12:02 AM.
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Old 10-26-2006, 02:54 AM
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see i have read from many sources that the movies on DVD with black bars are not a part of the resolution.
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Old 10-26-2006, 09:05 AM
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Originally Posted by resevilfan86 View Post
see i have read from many sources that the movies on DVD with black bars are not a part of the resolution.
for 16:9 movies that is true but not for 2.40:1 movies
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