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#1
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Pinging Alan, Mike and David: more info on the Iwo Jima picture enlargements
Hi, guys.
Would you or anyone just lurking be at all interested in my posting the full text of the several E-mails I exchanged with the fellow who did those 1,600% image increase's of my Mt.Suribachi picture? Perhaps you might glean something useful that I didn't and clear this up. We'd all learn something in the process, maybe... -- ATM, aka Jerry |
#2
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Pinging Alan, Mike and David: more info on the Iwo Jima pictureenlargements
All Things Mopar wrote:
Hi, guys. Would you or anyone just lurking be at all interested in my posting the full text of the several E-mails I exchanged with the fellow who did those 1,600% image increase's of my Mt.Suribachi picture? Perhaps you might glean something useful that I didn't and clear this up. We'd all learn something in the process, maybe... Why not post them here? I've looked at the images posted in the alt.binaries group, and find the enlargement job VERY good. It is not something that can be done in photoshop (CS2), at least not anything simple. I do see artifacts, but every method has artifacts. Roger |
#3
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Pinging Alan, Mike and David: more info on the Iwo Jima picture enlargements
Today Roger N. Clark (change username to rnclark) spoke these
views with conviction for everyone's edification: Would you or anyone just lurking be at all interested in my posting the full text of the several E-mails I exchanged with the fellow who did those 1,600% image increase's of my Mt.Suribachi picture? Perhaps you might glean something useful that I didn't and clear this up. We'd all learn something in the process, maybe... Why not post them here? Yes, /here/...They're just text, I was just trying to gauge interest as the task isn't trivial...I've got to find them again, and reformat for best readibility and keep things in chronological order so people can follow what was said to who by whom. I've looked at the images posted in the alt.binaries group, and find the enlargement job VERY good. It is not something that can be done in photoshop (CS2), at least not anything simple. I do see artifacts, but every method has artifacts. Roger, enlarging or shrinking do not create artefacts to the strict definition of the term. These are blobs, streaks, spots, etc. near sharp corners and often on broad expanses of color or even brightness/contrast, and are caused almost excluively by the lossy nature of JPEG compression. In the 618 x 479 original scan that I posted, that I have no way of knowing who did it or how it was done or when, but is readily available in numerous web sites, it is likely that the image was saved, possibly edited and/or resized, then saved again back to JPEG, perhaps many times. Each time you do that, the damage gets worse until the image is just so much mush. Unless the original scanner just plain didn't know what they were doing, there wouldn't be any artefacts in a BMP or TIFF, but there well might be jaggies... -- ATM, aka Jerry |
#4
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Pinging Alan, Mike and David: more info on the Iwo Jima picture enlargements
All Things Mopar wrote:
Hi, guys. Would you or anyone just lurking be at all interested in my posting the full text of the several E-mails I exchanged with the fellow who did those 1,600% image increase's of my Mt.Suribachi picture? Perhaps you might glean something useful that I didn't and clear this up. We'd all learn something in the process, maybe... Yes, I would be interested. I wonder where the original negative is? David |
#5
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Pinging Alan, Mike and David: more info on the Iwo Jima picture enlargements
Today David J Taylor spoke these views with conviction for
everyone's edification: Would you or anyone just lurking be at all interested in my posting the full text of the several E-mails I exchanged with the fellow who did those 1,600% image increase's of my Mt.Suribachi picture? Perhaps you might glean something useful that I didn't and clear this up. We'd all learn something in the process, maybe... Yes, I would be interested. I wonder where the original negative is? I'd have to go digging to re-find who Joe Rosenthal worked for as a photo-jouranlist, but I imagine both the neg and the copyright are owned by them, probably for the Pulizter Prize winning flag raising shot, as well. But, I suppose Rosenthal's family may also have something to say. I searched around quite a bit almost two years ago to see if I could /buy/ a larger, higher quality print or a larger graphics file. If they exist, I couldn't find any foir sale. I would've paid a high price and if I ever do find a print or an image for sale, even into the hundreds of dollars, I will buy it in a NW minute! Yes, there's sometimes a larger print can be found in a book or on a calendar, but the few I've seen appear to have been printed from that same 618 x 479 image, hence the quality isn't any better for a re-scan, by definition, plus I'd have to deal with the "noise" coming from the half-tone printing process dots. Incidently, although I'd known about my father's "exploits" all my life, including the Worcester news paper photo, I didn't get the digital one until April, 2004. By sheer coincidence, on April 4, 2004 - the 91st anniversay of my father's birth - my wife and I joined the Big Beaver United Methodist Church in Troy, Michigan (that's about 10-11 miles NNW of Detroit). I was sitting in a pew thinking about the fact that we were formally joining this congregation when it hit me that it was also my father's birthday. So I set out to find more factual info about his Marine "career." During my search, I ran across yet another pic with my father in it. This one was taken by an unnamed Marine Combat Photographer, who was actually taking a picture of Joe Rosenthal from behind him. Joe looms large in the foreground, and only 3-4 Marines are shown small in the background. One of them, though, is my father. I have searched long and hard, including through some veterans groups, trying to find a way to let DOD, or at least the Marine Corps, know that my father /is/ in that picture. I don't have anything at like legally valid "proof", but I've got a number of data points, including other pictures here there and everywhere, that at least place him at the scene. But, sadly, nobody seems interested in adding even one name to the 20 men in the picture. Who knows, maybe /their/ families are also trying to get their loved one some recognition? Think I'm proud of him? Not. I am /extremely/ proud of him. While he won no decorations for valor, and was only promoted from PFC to CPL just before discharge in late November, 1945 mainly to entice him to re-up, he is still a really /big/ contibutor to the war effort in my mind. (No-thing to do with this NG,but I've got a neat civilian picture of him taken in 1959 with Chuck Connors, "The Rifleman", when Conners was touring the Plymouth Lynch Road Assembly Plant where my father works. He is shown with an ice cream cone behind his back. He'd just bought it for 25 cents on his relief and wouldn't throw it away. Then, the Chrysler photographer moved /behind/ him and took the shot. Chrysler gave my father the "8 x 10 B& W glossy as a souvenier) Given that a typical Marine Company was maybe 200-250 men, I'd guess that over 10% of the survivors of the /entire/ company that successfully assaulted Mt. Suribachi are in that photo! I'll start looking for the original E-mails between that fellow who did the digital enlargements and me, and see if I can put together a coherent story to post in this NG. If nothing else, /I/ would like to better understand the algorithm/technology that was used. Maybe someone can understand the math better than me, and can identify what software app(s) were used, so we could all D/L or buy them. Thanks for your continued interest, David. -- ATM, aka Jerry |
#6
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Pinging Alan, Mike and David: more info on the Iwo Jima pictureenlargements
All Things Mopar wrote:
Today Roger N. Clark (change username to rnclark) spoke these views with conviction for everyone's edification: I've looked at the images posted in the alt.binaries group, and find the enlargement job VERY good. It is not something that can be done in photoshop (CS2), at least not anything simple. I do see artifacts, but every method has artifacts. Roger, enlarging or shrinking do not create artefacts to the strict definition of the term. These are blobs, streaks, spots, etc. near sharp corners and often on broad expanses of color or even brightness/contrast, and are caused almost excluively by the lossy nature of JPEG compression. Enlarging and shrinking an image requires interpolation. ALL interpolation algorithms have artifacts, at least all I've seen. If you compare your original small image with the largest one, you can see artifacts. I'll point out one. From the left, go to the first raised rifle and the guy standing below the raised rifle (looks like his tongue is sticking out). No go to the next guy to the right in front. He has a funny smile with his mouth curved upward in an unnatural way (his left side) and a line goes almost up to his nose. If you look at the original image, it is obvious that area is really a shadow from his cheek. The interpolation mangled the guy's smile. I suspect the noise that was added in as to mask artifacts, but in my opinion, was done very well. Other artifacts include halos around contrast boundaries, a common sharpening artifact. Roger |
#7
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Pinging Alan, Mike and David: more info on the Iwo Jima picture enlargements
Today Roger N. Clark (change username to rnclark) spoke these
views with conviction for everyone's edification: Enlarging and shrinking an image requires interpolation. ALL interpolation algorithms have artifacts, at least all I've seen. If you compare your original small image with the largest one, you can see artifacts. I'll point out one. Resampling using any algorithm, interpolation or simple pixel resize, can and does produce damage. But the term "artifact" first came to prominence during the early experiences with JPEG, after people first saw the damage from over compression. From the left, go to the first raised rifle and the guy standing below the raised rifle (looks like his tongue is sticking out). No go to the next guy to the right in front. He has a funny smile with his mouth curved upward in an unnatural way (his left side) and a line goes almost up to his nose. If you look at the original image, it is obvious that area is really a shadow from his cheek. The interpolation mangled the guy's smile. I suspect the noise that was added in as to mask artifacts, but in my opinion, was done very well. Other artifacts include halos around contrast boundaries, a common sharpening artifact. I already said I could see the artefacts, but I don't think they were caused by resizing down to the original size I have from whatever it was originally scanned at, nor when it was resized up. Exagerated, yes. Created, I don't think so. Being that I'm a visual sort of a guy, I don't know how to use the analytical tools in PSP 9 to examine an image, and I don't parlez vous PS CS. So, I'm very curious to know how you can tell that your examples above were caused by interpolation and not the more likely cause, over compression at some point, and/or multiple open/edit/re-save cycles. -- ATM, aka Jerry |
#8
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Pinging Alan, Mike and David: more info on the Iwo Jima pictureenlargements
All Things Mopar wrote:
Today Roger N. Clark (change username to rnclark) spoke these views with conviction for everyone's edification: Enlarging and shrinking an image requires interpolation. ALL interpolation algorithms have artifacts, at least all I've seen. If you compare your original small image with the largest one, you can see artifacts. I'll point out one. Resampling using any algorithm, interpolation or simple pixel resize, can and does produce damage. But the term "artifact" first came to prominence during the early experiences with JPEG, after people first saw the damage from over compression. Artifacts in digital imaging is much older than jpeg. I learned of it in the 1970s in graduate school. Yes digital imaging was being done back then, pre CCDs. I was using a vidicon, 256x256 if I remember correctly, system that digitized with electronics filling 6 feet of rack space, and a fifty pound camera head, cooled to dry ice temperatures. Being that I'm a visual sort of a guy, I don't know how to use the analytical tools in PSP 9 to examine an image, and I don't parlez vous PS CS. So, I'm very curious to know how you can tell that your examples above were caused by interpolation and not the more likely cause, over compression at some point, and/or multiple open/edit/re-save cycles. Without knowing the exact techniques and algorithms used in the processing, one can't be sure of where things were introduced versus where they were exaggerated. In my experience with scientific interpolation, including writing imaaging interpolation algorithms, it is my experience that there is no perfect interpolation algorithm for this type of problem. What is the likely cause is that the interpolation in the upsizing is imperfect (causing the fundamental artifact) which the sharpening and other processing steps enhanced. Some algorithms invent data (e.g.fractals) which may look good in many cases, but is scientifically incorrect, thus all the added "information" is artifacts. Other algorithms try and do little "inventing" linear, cubic spline and others, but these cause other artifacts. One hopes the artifacts have minimal detriment to the final image appearance. Roger |
#9
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Pinging Alan, Mike and David: more info on the Iwo Jima picture enlargements
Today Roger N. Clark (change username to rnclark) spoke these
views with conviction for everyone's edification: All Things Mopar wrote: Today Roger N. Clark (change username to rnclark) spoke these views with conviction for everyone's edification: Enlarging and shrinking an image requires interpolation. ALL interpolation algorithms have artifacts, at least all I've seen. If you compare your original small image with the largest one, you can see artifacts. I'll point out one. Resampling using any algorithm, interpolation or simple pixel resize, can and does produce damage. But the term "artifact" first came to prominence during the early experiences with JPEG, after people first saw the damage from over compression. Artifacts in digital imaging is much older than jpeg. I learned of it in the 1970s in graduate school. Yes digital imaging was being done back then, pre CCDs. I was using a vidicon, 256x256 if I remember correctly, system that digitized with electronics filling 6 feet of rack space, and a fifty pound camera head, cooled to dry ice temperatures. Being that I'm a visual sort of a guy, I don't know how to use the analytical tools in PSP 9 to examine an image, and I don't parlez vous PS CS. So, I'm very curious to know how you can tell that your examples above were caused by interpolation and not the more likely cause, over compression at some point, and/or multiple open/edit/re-save cycles. Without knowing the exact techniques and algorithms used in the processing, one can't be sure of where things were introduced versus where they were exaggerated. In my experience with scientific interpolation, including writing imaaging interpolation algorithms, it is my experience that there is no perfect interpolation algorithm for this type of problem. What is the likely cause is that the interpolation in the upsizing is imperfect (causing the fundamental artifact) which the sharpening and other processing steps enhanced. Some algorithms invent data (e.g.fractals) which may look good in many cases, but is scientifically incorrect, thus all the added "information" is artifacts. Other algorithms try and do little "inventing" linear, cubic spline and others, but these cause other artifacts. One hopes the artifacts have minimal detriment to the final image appearance. Not exactly taking you on, but the above seems like spin to me. A minute ago you were lecturing me on why artifacts are created simply by interpolation, rather than by overenthusastic JPEG compression. But you still haven't shown anything quantitative to refute my definition of the term. Could you perhaps post some examples that either support or refute the various opinions expressed herein? As to "looking good but being scientifically incorrect", this is /exactly/ my point. Since normal people only look at and print images, not examine them mathematically except while post-processing their scans or digitals, the point you're making is not only moot, but irrelevant. I got into this thread only to point out that there are methods, which you say you've personally implemented in software, that can easily defy the "rules" of either upward or downward resizing. I still like the bigger images but haven't been able to track onto the techology used to create noise- free versions, but I still sleep fine at night with only a postage stamp picture of my father. -- ATM, aka Jerry |
#10
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Pinging Alan, Mike and David: more info on the Iwo Jima picture enlargements
All Things Mopar wrote:
Would you or anyone just lurking be at all interested in my posting the full text of the several E-mails I exchanged with the fellow who did those 1,600% image increase's of my Mt.Suribachi picture? I'm also interested. -- Mike Warren My web gallery: http://web.aanet.com.au/miwa/mike |
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