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To: pissant

actually this doesn’t really prove anything

>There is only ONE way for the lack of any green-shaded >pixels to occur on the image.

There are so many variables you haven’t mentioned including how the original was scanned, under what settings the scanner was at, the condition of the CCD, was it sent through an ADF, was it skewed, was it deskewed with software, was it scanned in a non lossy format and then converted later to JPG, if so how many times, what software did that conversion, and not to mention the original document and it’s condition.

You also talk about converting JPG to 8 bit using an editor and this is the reason for the green missing. The green could be missing for many reasons including the scanner and it’s settings, the settings when the document was originally converted into JPG and how many times that was done. Just converting to 8 bit doesn’t mean you lose green anyways. That process is called color quantization where you are going from say 24 bit to some more limited palette, 16 or 8 bit or whatever. If green is a predominant color in the image it would not be lost when going to 8 bit if the color quantization software is any good, that’s the whole idea behind color quantization. You generate a histogram of colors and use the most prevelant along with a small subset of general paleete colors. Sure doing this step is not as good as staying in 24 bit but certainly can’t be construed as the ONLY reason green was lost in this JPG scanned image.

JPG is a lossy algorithm in the first place and once the image was scanned it was converted from spatial domian into the frequency domain and the compression process was done. Not all JPG compression/decompression software is exactly the same and can produce different results. This was not mentioned. Do they have a non lossy format for the scanned document ? That would still be subject to limitations of the scanning device but certainly WAY better than lossy JPG that may have been scaled and compressed several times before hitting the website.

I worked in the document scanning industry as a software developer and have written JPG compression/decompression software and image viewing software and also worked on hardware for scanners. There are simply WAY too many variables you have not mentioned to draw any conclusions from these images. For all anybody knows these JPG images could have gone through several compression steps, and even some scaling. You would need to look at the original document because what we have here is not compelling evidence.

Also if they were going to fake it why not just fake the entire certificate rather than try photoshop trickery ? That’s a very simple looking certificate that could be easily duplicated.


67 posted on 07/15/2008 8:57:37 PM PDT by JohnInSoCal
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To: JohnInSoCal
There are simply WAY too many variables you have not mentioned to draw any conclusions from these images. For all anybody knows these JPG images could have gone through several compression steps, and even some scaling. You would need to look at the original document because what we have here is not compelling evidence.

Exactly.

Thanks for your post, and welcome to FR!

70 posted on 07/15/2008 9:22:24 PM PDT by cynwoody
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To: JohnInSoCal

Sure ace, create one like it via scanning. Welcome to FR, troll.


77 posted on 07/15/2008 10:29:55 PM PDT by pissant (THE Conservative party: www.falconparty.com)
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