>
> I guess I wasn't aware they were of two differing sizes until you
> pointed it out. I would normally expect such corruption to come from
> a truncated file. In that case, being too small is not of concern
> since the non-truncated version of the file would be larger.
>
> When I looked at both with a hex editor I was struck by their
> similarity. In fact, they were byte-for-byte identical up to the
> point of corruption of your file. The real difference was that your
> file was not truncated, it had an end of image marker, whereas CD's
> file was truncated. However, CD's file had good image bytes up to the
> point of truncation, yours did not stay good that deep into the image.
>
> That's when I got the bright idea to copy the extended good portion of
> CD's file and allow it to overwrite that same corrupt portion of
> yours. My hope was that maybe the corrupt area would get overwritten
> with good bytes at which point maybe there wouldn't still be any
> corruption. So in effect, the whole file could be repaired.
>
> Alas, not to be! The image simply became good a bit further, enough
> to match the area of good in CD's version, but the corruption
> immediately set in again. Thinking there may have been a loss of sync
> in transmission, I searched both copies of the files for short
> sequences of bytes in the other. There was no point where the two
> files had even a tiny amount of congruity past the point of corruption
> in your image. There was no way to put the files in sync and create a
> full image.
>
> My next guess was that the original truncated file had been on a
> crashed hard drive, and that during recovery it had gotten
> cross-linked with another file, thus ending up with an end of image
> marker. So I searched all the other files in the folder for a short
> sequence of bytes found in the corrupt area of your copy of the file.
> Nothing!
>
> My last attempt at sanity was to measure the height of the image frame
> on my monitor, and the height of the good part of the image as
> presented by CD's version, then worked out the ratio of good to bad
> and calculated a presumed full file size for a complete file. It
> matched yours within 4k but it seems evident to me your copy contains
> bytes from some other jpeg.
>
> I'm stymied.
>
> I checked the other file too. They both remain congruent up to the
> point of corruption, which is very deep in the file. CD's file
> finishes off fine, no corruption in the horizontal, and has an end of
> image marker.
>
> Your copy goes corrupt in the horizontal near the end. It too has an
> end of image marker, but is a much larger file than CD's - remember
> the two are congruent to the point of corruption, so it stands to
> reason it too has the ending bytes from some other jpeg.
>
> Now I'm really stymied!
>
I agree - your evidence has convinced me :)
It does seem as tho my versions have been the product of a merger to try
and correct the corruption and so hence the larger size. This is the usual
trick so seems quite likely.
I would say we should go with the CD images then.
Just leaves the thumbnail - the CD thumb appears completely different from
the other thumbs. I suspect this comes from when they changed it from UA to
GA. I ripped GA whereas CD had ripped UA. Quite unusual :)
Anyway i'd rather stick with my version of the thumb more for consistency
than anything but in this case im happy to go with either :)
Regards
n@@dles
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