Hi,

> Changing image size on the fly could be a bit problematic w.r.t the
> threading - i.e. one threading is reading the image assuming a certain
> size, then you change the size delete memory and reallocate leading at
> the same time so you'd need to introduce a mutex on read and write
> access to the osg::Image, we made need to modify osg::Image  or
> osg::ImageStream to achieve this.

Yes, I understand. But I would expect a crash or so. Aren't reading and
writing already guarded, writing new data *is* done in my_render_frame()?

Anyway, I will go ahead and add locking to Image, since I believe this is
the place to do this. I will let you know.

> Double buffering would be one way around this - the writing thread
> writes to its own image, and the reading thread reads from its own
> image, then onces both are finished you can swap.  This would still
> need mutexing.

Raymond

>
> Robert.
>
> On 8/9/06, Raymond de Vries <[EMAIL PROTECTED]> wrote:
>> Hi,
>>
>> I have my streaming video texture plugin ready, so thanks Robert for
>> your
>> support. For this I have followed the strategy in ReaderWriterXine.cpp
>> where:
>> - allocateImage() is done in the open() routine (so once)
>> - setImage()/setData() for each new frame
>>
>> Now I am working on changing the image size during streaming. I've
>> skipped
>> the image allocation in the open() routine and now trying to allocate a
>> new image for the imagestream (allocateImage()) in my_render_frame()
>> (just
>> before setImage(), line 180 in ReaderWriterXine.cpp). This does not
>> work,
>> however.
>>
>> Anyone thought where should I allocate a new image with different size?
>>
>> thanks a lot
>> Raymond
>>
>>
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