Well, Adobe builds the capability in for some reason, as do other document management system vendors. You don't think that file size matters for people storing thousands of pages, as the users of a document archiving system would?
It just now occurred to me that you can get a 4 X REDUCTION in memory size by using the larger pixels, but you get a 7 X INCREASE in memory requirements by switching from a Binary bit map to 8 bit gray-scale, and a 15 X increase by switching to 16 bit Color!...How is this supposed to be a benefit?
I'll take one more shot at this. There is no switching from a binary bitmap to grayscale. The scanning and processing software recognizes most of the letters either as text (if it's doing OCR) or at least as pure black. It handles those in one way. It recognizes the background as a color image and handles it in another way. Because the 'R' is faint compared to the other letters, it's treated as part of the background and processed as just a gray area of the background image. The whole background image is stored as a color image, and the 'R' is part of it--it's not "switched" to being in color, nor does it have its dynamic range increased. (As I'm sure you realize, if you scan a black-and-white photo at the same settings as you would use for a color photo, you get a file the same size as if it were a color photo. The computer doesn't "understand" that gray isn't really a color--unless you tell it so.) If the background is downsampled, the 'R' is downsampled along with it. The important thing is that the computer doesn't know it's an 'R'. We can recognize it, but the software just thinks it's a gray smudge.
Here's something from a vendor of PDF compression software:
High accuracy recognition rates are achieved by leveraging advanced image processing techniques including: re-sampling, foreground and background separation, auto-rotation, and font learning. [Emphasis mine.]And this theory makes more sense to you than different source image formats?
What I see is a choice between believing that the BC anomalies are the result of some combination of automatic PDF processing functions; or they're the result of someone sitting down with multiple source files and (using Adobe Illustrator, mind you, not Photoshop or some other tool much better suited to the task) copying and pasting letter by letter--a 'B' from this file, an 'R' from another, a different 'R' from yet another; a box from here, another box from there--to assemble a forgery. Occam's razor only cuts one way for me on that question.
The DESTINATION SURFACE is all one resolution and either a 24 or 32 bit color pixel depth. It can "represent" 4 x larger pixels by using 4 pixels of it's surface to represent each pixel of the image. It can "represent" binary bit map images by turning all 24 bits on (White) or off (Black). The destination surface resolution is a CONSTANT. It ought not "create" a 4x normal pixel resolution on a background smudge it doesn't recognize. It ought to simply render to the surface the image that is loaded.
Now you seem to be making the argument that on a supposedly black and white ORIGINAL document, the scanner (and software) cannot distinguish sufficient contrast between the BLACK of the letter, and the WHITE of the page to recognize it as anything but the background, yet our eyes can easily distinguish that it is not?
(As I'm sure you realize, if you scan a black-and-white photo at the same settings as you would use for a color photo, you get a file the same size as if it were a color photo.
It *IS* a color photo. It's colors are gray scale renderings of the three primary colors as represented by the binary bits in the memory surface allocated for this purpose.
The computer doesn't "understand" that gray isn't really a color--unless you tell it so.) If the background is downsampled, the 'R' is downsampled along with it.
Downsampled? A new term for "Deus ex machina? Yeah, when I don't recognize something, I make the resolution four times worse, rather than just leave it alone.
The important thing is that the computer doesn't know it's an 'R'. We can recognize it, but the software just thinks it's a gray smudge.
If you are making a copy, the computer doesn't need to know what it is, n'est-ce pas?
I have thought about this a bit. A better argument for you would be that the Adobe program is using a MPEG type compression algorithm on image tokens somehow deemed by the software to need less detail. You could further argue that this is a benefit in applications OTHER than creating exact copies, for which this software might be used most of the time. (rapid video rendering comes to mind.) Then the question becomes why some moron thought it was a good idea to do this instead of making an exact copy? (It still doesn't explain the "Halos" around each letter either.)