On 8/30/07, Stephen Moss wrote:
Fellow python users,
After some more work on the problem....
I discovered that:
- small files opened in the GUI are "select" -> "none" but
- larger files are opened "select" -> "all" !!!!
I find this extremely difficult to believe.
I think it's more likely something about the image that causes
gimp_by_color_select to behave in a way you don't expect. For example,
if your huge image is indexed, that might cause this effect you
mention; the threshold selection options (eg, in 'magic wand' and
'select by color' tools) do work in indexed mode, but the result often
isn't meaningful (since the threshold is applied to the colormap
indices of the pixels, rather than the actual colors they point to.)
Does toggling 'sample merged' effect the result?
I have done my tests with:
Antialiasing ON (does nothing anyway, AFAIK)
Feather OFF
Select transparent areas ON
Sample Merged OFF
Select by: COMPOSITE (if you had been using the wrong value here, it
could have tripped you up too.)
On a 8000x6000 PNG image (on an AMD Duron, Ubuntu 6.06, GIMP [latest
from SVN] ), I have tried to reproduce your problem with both an
indexed and a grey image, and neither display the behaviour you
mention. The select menu always shows 'None' as disabled and 'All' as
normal after the image is opened, indicating that the selection is
currently empty (None). In fact, the menus do not indicate whether all
pixels are selected -- you can see that the 'All' menu entry is never
disabled, so even when the selection already covers everything, you
can still Select->All.
If you want to check the state of the selection, there is a 'Selection
Editor' dockable you can access which provides a clear display of the
current selection mask.
Lastly, it's possible that the file plugin for whatever format your
image is in is interpreting some data wrongly and so mistakenly
resetting the selection mask to this confusing state. What format is
your input file(s)?
