[QUOTE=jt-3d]I'm thinking, and indeed thought in the other thread about the same thing, that this image is already pixelated by the data transmission so when you blow it up, you get larger versions of the pixels.
QUOTE]

That makes good sense and is probably the correct explantion. My concern all along has been why this particular image is so pixelated in comparision with other Mars Express images. Perhaps this one experienced transmission problems while downlinking. That is one of the questions I posed to Dr Neukum.

The next post states that I have been told this before, that the strange shapes are compression artifacts. I keep saying to myself, "Yes, but" why so only on the Hale image? Your posit that the data arrived from the Mars Express already degraded sure could be the answer, but I would like to be able to verify that.

Thanks for the post.

JP

J.P.,

You never link the original images, so I went to the ESA website and grabbed one of the Hale Crater. It may or may not be the one you started with, however it illustrates the idea.

Here's the original:

http://esamultimedia.esa.int/images/...leCrater_H.jpg

If you look across the bottom of the image, you see all sorts of square and rectangular "shapes", especially in the light parts of the picture.

Let's consider two possible explanations:

1. The shapes are digital artifacts.
2. The shapes are not natural, and therefore were created by an alien civilization.

Now, if you look closely, you'll see that the shapes are "splattered" across all the smooth parts of the image.

The shapes have no "height". I see no shadows, no dark spots, like the surrounding craters.

There is blurring evident in many parts of the image.

So -- knowing the nature of digital cameras and image processing, which of the two explanations is more likely?

In fact, which is much much much much much much much more likely?

Señor, it is I who asked you your theory, since twice it has been suggested to you that it is compression artifacts. But perhaps you don't understand, since you answered a question with a question.

Ahh, so contacting this Professor Dr Gerhard Neukum of the ESA looks like your best bet. As for answers from forum members so far, I think you have a consensus that the photos suffer possible graphical glitches from compression artifacts. Now if you don't like that answer...

Good points. The fact that is much much more likely is bad image processing. The blurring in parts of the image are explained by the German processors is that "translucent clouds" obsured part of the image. I did link to the original images on the "Major Tom" post. This is the kind of answer I expected from the post, ie, a serious attempt to explain what we are seeing. Thank you.

JP

Thank you for your interest. Now let me examine what you have to offer. According to you, and others, I have be "told" several times that what I am seeing is compression artifacts. So that should settle the matter, right? Wrong. Let me turn the tables on you in a small exercise of logic. Suppose I "told" you that the obvious answer to the strange shapes was that based upon my experience as an Air Force pilot that the shapes were obviously El Paso, Texas, from 42 thousand feet.(The image really does resemble El Paso, strangely enough) You would probably say, "Prove it." So if I were right, I would go on to say that this shape matches Biggs Air Force Base and that funny triangle is the city center, etc. etc. In other words, I would provide some "proof" of my claim. All of you who have stated that what I am seeing is compression artifacts have made that assertion as if stating it made it so. I would like to see some of you who are making this assertion to back it up with some facts other than your assertion. Simply put, show me some examples of bad compression artifacts and how they could have crept into this photo. Show me that the odd shapes are typical of compression artifacts. Tell me how bad a bad transmission of data from the Mars Express could have degraded the image so much that a 200% blowup would cause such distortions. Try me, I'm honestly open to what you have to say. But don't tell me that because you say that's what it is, that the matter is settled.

As for you, Senor Big Eggs,(Nuts) (?) (By the way, they call me "Big Nuggs" from my gold mining endevors), I am short on theories given the animosity of the forum. I just want to know what causes these artifacts, and I am not going to go away because someone says, without any backup, that they are "pixelation or compression artifacts."

Thanks for the post.

JP

Uh, wrong. You don't get to turn the burden of proof onto us. You picked the Life in Space forum didn't you? Why do you think your images belong here? Back it up. Show it's not life on Earth that created your curiosities.

Nonetheless, if you want an example of JPEG artifacting, here are a couple of recent MER Spirit Microscopic Imager images at the Planetary Photojournal, one a 1-megabyte TIFF and one a 190K compressed JPEG.

TIFF
JPEG

Presumably (I presume!) the TIFF file is closer to the received raw image (though I suspect it has lost some dynamic range for presentation). The JPEG is compressed down to 20% the size of the TIFF. Compare them at a few-hundred percent magnification and witness the bountiful JPEG junk.

How they could have crept into the image you question? How should we know? It is a JPEG file. It is compressed. ESA processes images they put on display; they do all kinds of things to make them pretty for public consumption. These images on the ESA website are not scientific data files. They are pretty pictures. For one, it is a color composite and therefore has been manipulated from the original gray-scale images. For another, it is a manufactured 3D perspective view synthesized from the original 2D images. That involves at least creating a 3D model from one or more steroscopic pairs, surfacing the 3D model with a colorized 2D image, rotating the 3D model in space to get a slanted perspective view, perhaps rotating that to achieve the most aesthetic view. There's a huge amount of digital image manipulation going on there.

What is the pedigree of the image you question? When you can tell us how it was manipulated before ESA published it, then we can have a chance of pointing where the worst of the artifacting was likely inserted.

Why do you assume the artifacts were introduced during the transmission? I've never heard of that happening. Images may be compressed with loss before transmission to save bandwidth. They are transmitted digitally, so no noise would enter the image during transmission; either the data is there or it is not there. The compression artifacts were created either prior to transmission, or after reception during typical dressing up of the image for pretty-picture publication on the site.

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Lots of things cause the artifacts. The two most common types we see here are due to overenlargements of JPEG compressed images and introduction of artifacts by image processing (usually in Photoshop).

JPEG is a "lossy" compression technique, which means that a JPEG image has less data than the original, based on what the humans normally notice the most. In effect, it is designed to fool the eyes. That makes it handy for reducing bandwidth on "general consumption" images for the internet, but the process necessarily introduces artifacts. One type of artifact appear to be geometric shapes, especially if a portion of the image is enlarged. The degree of compression will determine the extent of artifacts introduced. You can test this yourself - just take some images, save them in JPEG at various compression levels, then take "close ups" of various sections. Different parts of images and different types of images will result in a variety of artifacts.

Image processing in Photoshop and similar products causes additional loss of information in an image and necessarily introduces additional artifacts - things that were not in the original image. Also, processing can make JPEG artifacts much more obvious. The upshot is that JPEG images are not considered good evidence for this type of image analysis. Photoshoping makes it even less useful.

Of course, these issues are not the only possible sources of image artifacts. You have to consider the characteristics of the imaging equipment, what filters or settings were being used for the image, any transmission issues, further processing after reception and every other step up to and including the characteristics of the video display you use to view the image.

Well, yes. This type of claim is very common. We've seen a number of examples in many different contexts of overprocessed JPEG images. Others have given you links to examples of compression artifacts. Here again is a discussion of the issue:

http://www.badastronomy.com/bad/misc...artifacts.html

Actually, I would say that this was an example of paraidolia. Recently, we had another fellow that looked at Mars rocks and thought they were "obviously" plants, bugs, sheep statues and many other things. In this case, low resolution blocky shapes without additional contextual information prove absolutely nothing, regardless of what you think they may look like. Given their source (photoshopped JPEG images) there really isn't much more to say about it.

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I've merged the two threads as they deal with the same topic.

This is most curious. So you actually expect that by blowing a picture up, to 200% or 500% that there should be a corresponding improvement in resolution, as well ? Or that small graphical errors should be less apparent than at native resolution ?? And as I've stated previously, you'd read what seems to be the leading theory here without actually presenting one of your own (sorry- are you really stating that you're and ex-pilot and that this is a treacherous ESA image of El Paso?). I don't quite understand if you're trying to cast aspersions on the image, or image processing technology, or if you're alleging alien life/cover-up -type theories.

There is certainly no need to be rude. There is no animosity here. The pixelation/compression-artifact "theory" has mountains of evidence behind it, and is a natural answer to the problem. If you have a competing theory, it is up to you to provide evidence for it, not to become angry at all of us.

It's pretty cool that you have a gold-mining background: the secret dream of some of us men. Don't try to mine for any hidden meaning(s) in my name, however- Wolverine imagines obscenity everywhere and hands out bans & suspensions, per some arcane interpretation of FAQ rules, like there is no tomorrow. "You have been warned."

Well, if you don't listen, people start to get sarcastic. Simple as that.

Yes, Pizza Hut has 5 locations in Berlin. Send him a meatlovers.

If you take the original photo and zoom in, do you see geometric artifacts? If not, then why do you think that heavy manipulation of the photo is going to give you a "more accurate" picture?

Photoshop is not an analyizing tool. It is a photo manipulation tool. I'm no expert on photoshop by any means, but I do have a working knowledge of it. It doesn't take much to drastically change the image in photoshop. And from what you say you did to the photo, you did alot of manipulation.

One has to ask why you did those specific changes in the first place? Why set your RGB to very little red, almost no green and full blue? Why sharpen the picture then procede to unsharpen it? Was there a scientific reason for these changes, or did it just look cool?

The point that I'm getting at is that if the original photo didn't show anything "geometric", why would the modifications you did expose these patterns? Or were they introduced by the above mentioned changes to the photo.

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"The universe is driven by the complex interaction between three ingredients: matter, energy, and enlightened self-interest." - G'Kar

Reading through this thread, I'll agree that people jumped on you kind of hard, J.P. So many others have "discovered" this phenomenon that the locals are kind of tired of it. It's kind of like when you go ask a question at the help desk, unaware that 20 people have just asked the guy the same question; then you wonder why he growled the answer at you.

You did some things right: You gave the source image, the software that you used, the process that you used, and showed your results.

You also did some things wrong: You could have simply asked, "What is causing these patterns?" Instead you made claims, some of them quite offensive to the people who have worked very hard for many years to build & operate this probe and to provide these beautiful pictures. I know you may not have realized it, but some of the things you said in your original post were very, very insulting.

Now then, on to the jpeg artifacts. You asked why they show up on the plains but not the mountains. These artifacts are most likely to show up in low contrast areas of the image, where there's not a lot of detail. The compression algorithm pays attenion to obvious changes, but makes up for that by compressing large areas where things don't change brightness or tone as much. The sky is an example of this. So is human skin.

To experiment with this, leave Mars behind and look at some ordinary pictures from here on Earth. Here is an example. Now, perform the exact same adjustments to this picture. Notice that you don't get such obvious artifacts on the eyes & hair (though there are some), but they're quite prominent on the cheeks, forehead, wrist & neck.

I'll bet you really wanted to find evidence of "something" in the Mars photos. You're not alone. But you need to understand the nature of what you're looking at; not what's in the picture, but the nature of the picture itself. How is the camera built? How is the image recorded? How was it transmitted? How was it processed on the ground? How is it displayed to you? What losses and alterations is the image susceptable to at each step of the process?

Now here's the really cool part:

If you're genuinely interested in these details (as opposed to somebody playing around with photoshop), if you study the relevant subjects and learn how it all really works, then you really honest-to-god can qualify on a spacecraft imaging team at ESA or JPL. Heck, you look at the people working there, they are just people in their 20s & 30s with a lot of curiosity, drive and enthusiasm for what they do. You could be one of them, and you can get the raw data and do this for real.

Of couse, then you will find out what it's like to have your life's work called a hoax...

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"Transport of the mails, transport of the human voice, transport of flickering pictures - in this century, as in others, our highest accomplishments still have the single aim of bringing men together." St. Exupery

Just ask Copernicus, Kepler, Brache if you don't believe Count Zero. It goes with the job.

Welllll... That's sort of talking about the guys up at the summit of discovery. I'm talking about the guys who get to build stuff. Who built the camera on the Voyager spacecraft? I don't know, but I do know that every time one of "his" pictures appears on TV or in a textbook or journal, he holds his head high.

One of my favorite episodes of From the Earth to the Moon is about the engineers who built the Lunar Module. These guys had to work long hours for years to solve a myriad of problems. The end result was seeing these things that they had built with their own hands carry men to the Moon.*

The point I was trying to make is that J. P. could become one of these people. He doesn't have to be a genius. If his ambition, discipline & perserverance matches his curiosity, then he could be one of the people building the next manned lunar lander. It is within his reach.

Rick

*I know a little bit about that feeling: I work in the only plant that makes the Digital Mirror Device that is at the heart of DLP televisions & projectors. Every time I see an ad, or a display in a store for this revolutionary new technology, I say to myself, "There's a little bit of me in there."

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"Transport of the mails, transport of the human voice, transport of flickering pictures - in this century, as in others, our highest accomplishments still have the single aim of bringing men together." St. Exupery

First of all, I would like to thank 01101001, Count Zero, Metricyard for taking the time to be patient and provide me with some excellent instruction and advice. You can rest assured that I followed up on all your input, learning all the way. Count Zero, I do apologize if I inadvertantly insulted anyone. Thanks especially for the explanation of the compression algorithum in low contrast areas. By the way, the lady is a real beauty. Metricyard, you are correct in that over processing was not necessary. On the image attached, I have corrected that mistake by only increasing contrast and brightness. I guess I fell into the habit because I use Photoshop to process my astrophotos, trying to pull out every bit of detail possible. So considering all your advice, here's what I did next.

1. Went to the ESA German site and downloaded their image of the Hourglass Crater, a 12 MB JPEG. I then compressed the image twice as a JPEG, reducing it to 1.89 MB. I then enlarged it to 200 %, and cropped out a 3 by 3 inch section and saved it. This is the first image attached. Compression artifacts are seen throughout the image, pretty well evenly distributed. I used the Hourglass Crater photo because it is the same camera that took the Hale Crater photo. I wanted to compare compression artifacts to compression artifacts using images from the same system.

2. Went to the ESA site and downloaded their image of the Hale Crater, a 5.8 MB JPEG. I then compressed the image once as a JPEG, reducing it to 1.2 MB. I then enlarged it to 200%, and cropped out a 3 by 3 inch section. This is the second image attached. The compression artifacts on this image are strikingly different than those on the Hourglass image. You also can see faintly in the upper left hand corner, in the mountain area, the beginning of additional compression artifacts similar to the Hourglass.

3. Went to the ESA site and downloaded their Bitmap image of Hale Crater, a 17.2 MB file. I enlarged it 200 %, cropped out a 3 by 3 inch section, and in keeping with Metricyard's advice, only increased the contrast and brightness in Photoshop. That image is number 3.

Here is what I think about the artifacts on the Hale image.

1. They are compression artifacts.
2. They are processing artifacts.
3. The shapes have been added during or post processing.
4. They are Mars surface artifact.

I'll take each in turn. They are compression artifacts. This seems to be the consensus of opinion. However, I am still not convinced for the following reasons: Comparison to the Hourglass shows the Hourglass artifacts being rather homogenious throughout the entire image. The Hale artifacts are irregular, odd shaped, and sporadic throughout the image. In addition, certain parts of the Hale image mimic very closely the Hourglass, indicating that homogenious artifacts are also present.

They are processing artifacts. As one of you mentioned, we do not know all the steps Dr Neukum and his team went through to make this "pretty" picture. The odd shapes I see certainly could have been introduced during this process. This is a very likely answer, but I won't know unless my query to the good Dr brings an answer.

The funny shapes on the Hale image have been added post processing. For example a hacker lifting the Hale picture off the site and layering in some funny artifacts. In other words, a hoax. I consider this very unlikely due to the numerous places one can find the original image.

They are Mars surface artifacts. Highly unlikely due to the known environment on Mars, now and in the past. But since the odd shapes are there in the image, this cannot be ruled out completely.

My conclusion is that the probable reason is number 2. I think I'll work on that one for a while.

I am not one of those people who see little green men hiding behind every over-enlarged image of Mars. But when I do seem something odd I like to find out what is causing it. I initially posted it here in the "life" forum, to be honest, to stir the pot a bit.

By the way, I'm old and retired with probably too much time on my hands.

JP

Attached Images

	Hourglass Crater Compression Artifacts.JPG (115.3 KB, 11 views)
	Hale_Crater_3d2 5.8 meg jpg reduced to 1.2 MB.JPG (95.1 KB, 11 views)
	Hale Crater German Site 17meg bitmap original.JPG (42.4 KB, 11 views)

What's the reason for the apparently exclusive hypotheticals? If an image is first compressed, say, to make it more manageable, and then processed to achieve some goal, and then you process the image some more to bring out rectilinear features, then how can you eliminate compression as one of the reasons for patterns you see just because it doesn't look exactly like other compression artifacts you have witnessed.

Don't rule out the possibility of combinations of possible sources for the artifacts you see.

You really need to ask your questions about either original unprocessed raw images from the source (with the knowledge of exactly what processing said source may have done before the image was available) or images for which you know the precise processing steps performed before you took custody.

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Here's a comparison you can try: Here is a Mars Express image stored in two different formats; tif & jpeg. The jpeg is 540kb, whereas the tif is 18,129kb. Why is the tif so much more? Because it does not compress data the way a jpeg does. It's pretty obvious why most of the pictures are only posted as jpeg. Remember that if you save the tif as a jpeg, you will introduce compression artifacts.

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"Transport of the mails, transport of the human voice, transport of flickering pictures - in this century, as in others, our highest accomplishments still have the single aim of bringing men together." St. Exupery

Mods, please bear with me. I think that the illustrations are neccesary to make the point.

Here's an experiment to illustrate compression artifacts:
1. From the "Start" menu on your computer, open up Programs>Accessories>Paint.
2. Set your image attributes to 2 x 2 inches.
3. Select the "Draw Line" option and select the broadest width.
4. Select "Draw Ellipse" and draw a circle:


5. Save this as a .bmp file (circle1.bmp).
6. Now click on the bucket fill icon and select the red color.
7. Click on the inside & outside of the circle to fill it in:


That looks nice & neat.
8. Save this as circle2.bmp
9. Open the circle1.bmp file again.
10. Save it as a jpeg file (circle1.jpg):


11. Click on the bucket fill icon and select the red color again.
12. Click on the inside & outside of the circle to fill it in:


Whoa! Yuck, what happened? When you saved it as a jpeg, it compressed the bits around the circle. If you check the size of the files you saved, you'll find the .bmp files are ~104kb, whereas the .jpg files are ~4kb.

The moral of the story is that jpegs are great for storing & transmitting images efficiently, but are not good for any sort of high-resolution photoanalysis.

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"Transport of the mails, transport of the human voice, transport of flickering pictures - in this century, as in others, our highest accomplishments still have the single aim of bringing men together." St. Exupery

Wow, excellent point and observation CZ.

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No, I don't think I made the hypotheticals mutually exclusive. I just said that I had yet to be convinced that the Hale images artifacts were typical compression artifacts. And please note, I purposely downloaded a large 17MB bitmap image, enlarged it 200% and only increased contrast and brightness on the third image I posted. Even without contrast and brightness adjustments the shapes are there, just a lot fainter. I do not consider that over processing. Which led me to the second hypothetical that the funny shapes were introduced into the image during the original manipulation of the data. And, I agree with you here, that a combination of processing steps by the German team could have led to the shapes, and that I'll never know unless I can get a rundown on the specific steps they took. So they could be compression artifacts of a type I have yet to see in anyone's examples (hypothetical 1) brought about by the data processing steps (hypothetical 2). So the two could be mutually inclusive. Now I have to go practice the circles and red paint lesson of the previous post.

JP

Attached is a cropped portion of the straight-on Hale TIFF ("RGB Colour Image") (warning: 17 megabytes), from Free University of Berlin :: Mars Express :: Hale Crater. It might be less processed than the synthesized 3D perspective you first looked at. It's from just left of the central crater peak. The only processing I did was cropping it and saving the result as a bitmap for attaching. The TIFF looked the same to me.

HaleArtifacts.bmp
(Excerpt from image of Freie Universität Berlin, Remote Sensing of the Earth and Planets group, Institute for Geosciences, Malteserstr. 74-100,D- 12249 Berlin.)

Grab it and magnify it a few-hundred percent. Focus on the left half of the image. The artifacts are subtle, but compare the blocks of checkerboarding, the blocks of vertical bars, the blocks of horizontal bars. That's astoundingly close to classic JPEG artifacting, like the explanatory DCT image at Wikipedia: JPEG.

My cropped excerpt isn't an enlargment but the block size evidences that it's been enlarged about 50%; I measure what should be 8x8 pixel JPEG DCT blocks to be roughly around 12x12. That's processing applied to the compression artifacts. Also, the block edges don't seem to be strictly horizontal and vertical, but tilted a few degrees clockwise, as if a compressed image were subsequently rotated. More processing. It wouldn't surprise me if the image were also smoothed a little after compression, for beauty; the artifact blocks have soft edges. More processing.

It's clear to me the original image captured on the Mars Express CCD endured JPEG-or-similar compression, and then further processing beyond that, before it made it to the FU Berlin website for public consumption. What would make it clear to you?

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It is clear to me that the image suffers from compression artifacts. The entire image displays exactly what you have been saying. The boys in Berlin must have "pushed" this image a bit, because the JPEG compression is embedded in the TIF image. Thank you for taking the time to lead me up my slow learning curve. The strange shapes are just that, strange JPEG compression artifacts. I guess life on Mars will have to wait for the microbiology guys after all.

To all who participated in this thread, particularly those of you who exhibited some patience with me, thank you also. It was stimulating.

JP

Yay. Thanks for saying so. Don't be disappointed. Mars is still a wondrous place. Nor feel alone. I imagine we've all been curious about similar in images until we figured out what we were really seeing. And some -- Richard C Hoagland leaps to mind -- still appear not to have figured it out. And thanks for having an open mind throughout.

How about if the next time -- there will be a next time -- someone comes here with magnified images, from some unearthly place, that shows evidence of rectilinear tool marks, you take your turn at trying to explain that their likely origins are mankind's very own imaging tools? It'll be fun.

===

Edit: Adding some keywords for searchers.

People who wind up at the (formerly) recommended Hale Crater video may have have been drawn by this descriptive text and these keywords. Now, they might be drawn here. If so, I hope they consider reading the whole topic Crater Hale Revisited.

Also:

And...

Here's a little more for the more discerning searcher:

Keywords: skeptical, skeptic, skepticism, critical thinking, debunk, truth, reality, image compression, jpeg, jpg, artifacts, mars express, mars, martian, hale crater, fields, buildings, technology, baloney, bilge, bunk, bunkum, claptrap, flapdoodle, flimflam, hogwash, hokum, hooey, hot air, humbug, humbuggery, malarkey, poppycock, tommyrot, tripe, wrong

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In that case, may I "recommend" this: www.marsanomalyresearch.com
you'll find an explanation, of sorts, there.


Curiously, it's run by a guy called J.P.

Oh, yeah, lovely explanations. For instance, from:

http://www.marsanomalyresearch.com/e...ars-swamps.htm

"In my last two Reports #090 and #091, I've shown evidence of biological forest life on Mars so clear, straightforward, and in one's face that it is really hard to ignore or misinterpret."

Sounds like another Extrasense . . .

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I say there is an invisible elf in my backyard. How do you prove that I am wrong?

Disclaimer: Avatar is not an official NASA image and does not imply any specific interplanetary or interstellar capability.

The Leif Ericson Cruiser

The site is a gem I tell you! fun for hours.

Is that fun before or after the insanity sets in?

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I say there is an invisible elf in my backyard. How do you prove that I am wrong?

Disclaimer: Avatar is not an official NASA image and does not imply any specific interplanetary or interstellar capability.

The Leif Ericson Cruiser

After. Take my word, please.

I've appreciated the detailed discussion on this board's various threads re the Hale crater "civilization" evidence. I'm convinced now that it's compression artifacts.

One thing about other Mars anomalies constantly sticks in my mind, though: Arthur C. Clark believed that the martian "trees" photos really were 95% uncontestable evidence for large plant forms existing on Mars, and he wasn't a gullible fool. What are your takes on that?

If this has been discussed elsewhere on this website, please forgive me.