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 Post subject: Re: Picture quality scale by format
PostPosted: 21 Mar 2018, 01:07 
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elahrairrah wrote:
UMD video had a resolution of 480x272 if I remember correctly (the exact resolution of the PSP screen.) I've never seen a UMD movie in practice, but since the capacity of UMD was just under 2GB I can't imagine the bitrate on the video was very high if they wanted to put a whole movie on one UMD.

So to put it in perspective, the highest bitrate on DVD-Video is 6Mbps. A 90 minute movie at that data rate would need to just over 4GB storage, and a 2 hour movie would need 5.4GB (which is why dual-layer DVDs were necessary for a lot of movies at the highest bitrate.)

Thus in order to get at least a 90 minute movie on a 1.8GB UMD, the bitrate couldn't be higher than somewhere between 2-3Mbps. Even less than that if they wanted to be sure to be able to put a 2 hour movie on 1 UMD.

So if that were to be put on the list, it would at best be below DVD, but beyond that, wouldn't know where exactly to put it.


Sounds reasonable. According to Wikipedia (and this is not cited, so who knows if its true or not) UMDs were encoded at 720x480, but scaled down for the PSP.

Its been awhile since I watched one, but I remember they looked decent enough. Which is not surprising given the screen size. You could get a TV adapter to play your PSP on a TV.

But I agree that UMD would likely place below DVD.
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 Post subject: Re: Picture quality scale by format
PostPosted: 21 Mar 2018, 03:40 
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They probably used the same transfers as the DVD releases (which were 720x480) for the UMDs, but just downconverted them.
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 Post subject: Re: Picture quality scale by format
PostPosted: 21 Mar 2018, 14:01 
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They even had p0rn on UMD in Japan !

Has anyone ever seen one of those Sony HDVS discs in action ?

@ elahrairrah - Thank you for the very informative post earlier.
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 Post subject: Re: Picture quality scale by format
PostPosted: 22 Mar 2018, 05:14 
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Audioboyz1973...thanks for the explanation....

A W-Vhs tape from a BD source should look really good....that W-Vhs tape in a 32" CRT tv will "feel" more you know "Imax" than the DVD,but the DVD color resolution and lights would be much better I guess


A very interesting Wikipedia talk;

.-.....ED-Beta's "500" lines of horizontal luminance resolution could only be maintained with super-duper clean heads - after an hour or so of playback, it would start to drop off below 400 until the heads were cleaned again - ED-Beta was INCREDIBLY sensitive to head-clogging. Also, the color resolution of ED-Beta was 40 lines MAX and often much worse

LD's chroma res was the full 120 lines for Orange-Cyan (I-Axis) colors (40 lines for RGB Q-Axis) and later Kurary, Sony DADC, and (finally!) Pioneer LDC mastered/pressed discs had 2 MHz of full RGB (not just I-Axis) chroma bandwidth - which was encoded with Faroudja's SuperNTSC system.

Oh, one other problem with ED-Beta and SuperVHS as compared to LaserDisc - their luma bandwidth is too high for the noise levels of the tape - in other words, they made ED-Beta and SuperVHS sharper so you could see more of the noise... in terms of the 'optimal' resolution level VS noise tradeoff, SuperBeta and Super High-Band Beta-Is were just about optimal. If JVC had set the resolution limit of S-VHS to around 300 lines or so, it would have been a much better 'match' to the noise levels of the format and a better picture would have been the result... it's amazing that neither Sony nor JVC increased the chroma bandwidth... JVC had numerous patents for VHS to expand chroma bandwidth to beyond 100 lines for all 3 colors but in a backwards compatible manner - it worked in a similar manner to the 16-bit, 48kHz digital audio extension to S-VHS that was, sadly, never allowed to be released here in the USA. It was encoded by a depth multiplex 11MHz carrier "under" the video along with the analog AFM audio.

ED Beta color res 40 lines
SVHS color res 30 lines
LD color 120 lines
DVD color >240 lines

In analog output signal terms, typical luma frequency response maintains full amplitude to between 5.0 and 5.5 MHz. This is below the 6.75 MHz native frequency of the MPEG-2

DVD better signal to noise ratio plus component encoding

I love analog but we have a big winner on SD resolution formats the DVD .
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