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#190 opening / rewinding image sequences
The problem occurs e.g. for sequence of ppm images.
The task is:
open video stream as DPISPortC
go to start frame (using Seek())
do some processing on a sequence of frames
go to start frame (using Seek())
do some more processing on the same sequence of frames
If I use images.ppm as the file name and then e.g.
Seek(76) it is ok.
If I use images0076.ppm as the file name and then
Seek(0) it goes wrong. It's not that Seek picks up
images0000.ppm - it seems that the second Seek just
fails, & the Get()s just go on getting further images
from the sequence, as far as I can tell.
Bug or feature?
Cheers,
Bill.
test prog + 3 test images
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You can see what I mean by running the attached prog t.cc on
the test images also included. The first pass outputs
"test2", but the second outputs "test3", whereas I would
have expected it to output "test2".
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This is a feature. The file you give it to open is
currently assumed to be the first in the sequence.
Attempting to seek before the begining of the sequence
causes an error.
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The point is that the 2nd Seek() seems to do nothing at all.
Surely it should rewind to some point or other. Why does
it fail?
Cheers,
Bill.