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November 16th, 2004, 03:13 PM | #46 |
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One possibility is that fx1 already has progressive ccd's, they are just disabled for working in that mode.
It makes no sense that Sony would develop diffrent ccd models for each camera model. Would be way too expensive. Another thing about "better resolution". Sony's Japanise site tells that z1 has 1070000 pixel ccd's and there would be no reason for more pixels, because hdv is 4:2:0 format, isn't it? So with green ccd's pixel shift you can easily get 1440x1080 for luma and 720x540 for chroma components. |
November 17th, 2004, 08:20 AM | #47 |
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I may be wrong, but I understand 4:2:0 works on two fields to give the chroma (red difference & blue difference) sample (compressed),
so (something like this)... field 1 = Y sampled full (4), Ycr at every other pixel (2), Ycb no sample recorded (0) field 2 = Y sampled full (4), Ycb no sample recorded (0), Ycb at every other pixel (2) This makes the chroma sampling more like 8:2:2 (relatively speaking?!) but means the chroma compression is temporal (across two fields) unlike the more straightforward 4:1:1 of NTSC. I would think the spatial detail is improved (vs.4:1:1) on stills but drops on motion. Reds and Blues will 'lag'/'precede' the luma motion. I don't know of an easy way of extracting Ycr and Ybr 720x540 chroma information as it swaps from field to field... any ideas ? (please correct any of the above if necessary - any experts out there ?)
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November 17th, 2004, 09:13 AM | #48 |
Obstreperous Rex
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<< One possibility is that fx1 already has progressive ccd's, they are just disabled for working in that mode. >>
Actually no, this is not the case at all... both the FX1 and Z1U have identical CCD blocks, and they are NOT progressive scan... just wanted to clear this up now before it goes any further. |
November 17th, 2004, 09:20 AM | #49 |
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With interlaced picture each field is sampled separately, so chroma component pixel is same in lines 1 and 3, eg.
With quick googling I found this: http://members.aol.com/ajaynejr/vidbug2.htm heath |
November 17th, 2004, 09:31 AM | #50 |
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<<<-- Originally posted by Chris Hurd : << One possibility is that fx1 already has progressive ccd's, they are just disabled for working in that mode. >>
Actually no, this is not the case at all... both the FX1 and Z1U have identical CCD blocks, and they are NOT progressive scan... just wanted to clear this up now before it goes any further. -->>> How can you be so sure? Do you have specs for that ccd? Anyway, this is getting little funny; EBU announced their recommendations for hdtv in Europe last month and it is that all hdtv in Europe should be progressive. This makes sense, because there are no interlaced displays after couple of years. Now sony offers a standard (1080i50) that nobody benefits... With new chips there should not be any noticable price diffrence with interlaced and progressive. Do they really think that hdcam buyer would buy hdv if it had progressive picture? |
November 17th, 2004, 10:02 AM | #51 |
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Hi Toke,
I stand corrected on the 4:2:0 sampling, it appears that the even/odd lines do not refer to field lines but are even/odd per each field (lines 1 and 3, 2 and 4, as you put it). This means that extracting to 720 x 540 must produce an interlaced image IF all chroma samples are to be retained, ie just drop the 4:0:0 lines, but keep the 4:2:2 from EACH field. That also means that to 'drop-every-other-field' to get 540p will still leave you with 4:2:0 sampling - so a smarter de-interlace method should be used to maximise the chroma info present on the 1080i ts. Any ideas on how DVFilm / MB handle 4:2:0 ?
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November 17th, 2004, 10:59 AM | #52 |
Obstreperous Rex
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Hi Toke,
<< How can you be so sure? >> Well, for one thing, if these cameras offered true progressive scan, Sony would say so. Instead, they have insisted all along that they are NOT progressive scan. Why would they lie about it? << Do you have specs for that ccd? >> Yes. See http://www.linuxelectrons.com/articl...40907063048435. Hope this helps, |
November 17th, 2004, 12:16 PM | #53 |
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<<<-- Originally posted by Chris Hurd : Hi Toke,
<< How can you be so sure? >> Well, for one thing, if these cameras offered true progressive scan, Sony would say so. Instead, they have insisted all along that they are NOT progressive scan. Why would they lie about it? << Do you have specs for that ccd? >> Yes. See http://www.linuxelectrons.com/articl...40907063048435. Hope this helps, -->>> Sony says that camera does not offer progressive scan. Has somebody from Sony said anything about ccd chip? Designing these chips and building production lines for them is so extremely expensive, that Sony needs to use several years same chips. If they have been clever enough, they have made a chip that also supports progressive scan, so next year when competititor brings out progressive camera and nobody wants interlaced anymore, they can also bring out new progressive camera and still use the same chips. This is of course speculation, but it makes sense? Nothing about interlaced/progressive in that article... And of course Sony wouldn't tell about hindering their new precious model. Anyway this is just what they (and others) are doing along all their product lines. Cheaper cameras can have more expensive camera's capabilities just by tweaking their software. Do you also believe that Sony is making diffrent ccd's (and chipsets) for HDW-730 than for HDW-900? Wasn't it about a year a go when cinealta doubled it's sensitivity just by software update? |
November 20th, 2004, 01:33 PM | #54 |
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Man, some people just don't want to see the truth... This entire thread was B.S. and a big waste of time, just lock it or delete it. |
November 20th, 2004, 11:14 PM | #55 |
Obstreperous Rex
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Sorry you feel that way, Donal... but we don't delete threads.
I don't see any reason to lock it but I might edit the thread title. |
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