mysterious little squares

Archived from groups: rec.photo.digital (More info?)

Most of my digital camera images come out fine, but a few seem to be
broken up into lots of little squares, or lots of vertical lines, or
horizontal lines. The little squares are JPEG doing an unreasonably
bad job. It happened for a wide range of resolutions, supposed
JPEG-qualities, and different cameras. I've run into other people who
have had the same problem with totally different setups.

Well, I finally figured out what was going on. The little-square
problem was plaguing ONLY THE PICTURES I'D ROTATED. The software I was
using claimed that rotation was a lossless operation, but it wasn't.
There wasn't anything wrong with any of the cameras after all. The
originals had been fine. But I'd corrupted them (alas, unrecoverably
now) by doing a rotate.

Humph. How come digital cameras don't contain a plumb-bob that tells
them how the camera was oriented when the picture was taken, so they
can orient the picture correctly themselves? Sure, I can find some
non-awful rotation software, but I really shouldn't have to be rotating
my pictures in the first place.

Archived from groups: rec.photo.digital (More info?)

bob_jenkins@burtleburtle.net wrote:

> Most of my digital camera images come out fine, but a few seem to be
> broken up into lots of little squares, or lots of vertical lines, or
> horizontal lines. The little squares are JPEG doing an unreasonably
> bad job. It happened for a wide range of resolutions, supposed
> JPEG-qualities, and different cameras. I've run into other people who
> have had the same problem with totally different setups.
>
> Well, I finally figured out what was going on. The little-square
> problem was plaguing ONLY THE PICTURES I'D ROTATED. The software I was
> using claimed that rotation was a lossless operation, but it wasn't.
> There wasn't anything wrong with any of the cameras after all. The
> originals had been fine. But I'd corrupted them (alas, unrecoverably
> now) by doing a rotate.
>
> Humph. How come digital cameras don't contain a plumb-bob that tells
> them how the camera was oriented when the picture was taken, so they
> can orient the picture correctly themselves?


Some do! But you normally have to use the crummy software that comes
with the camera to benefit then other programs will maybe re-read it &
re-rotate & all sorts of confusion.


> Sure, I can find some
> non-awful rotation software, but I really shouldn't have to be rotating
> my pictures in the first place.


Irfanview is good for this. Use the shortcut shift-J for lossless rotating.

--
Paul Furman
http://www.edgehill.net/1
san francisco native plants