Phil Endecott wrote: > Dear All, > > I have been playing around with the djpeg program (a trivial wrapper > around libjpeg for decoding) and there is a performance difference of > about 25% between the defaults and the fastest settings, with no > noticeable difference in the output (to my eye - no doubt there are > cases where it can be seen).
What does it do? 4:4:4 to 4:2:0 reduction while converting to RGB? > I'm therefore considering adding some flags to DirectFB so that the > JPEG provider can be used in different fast/slow modes. Any comments? Adding IDirectFBImageProvider::SetOptions() to be called before RenderTo()? > I've also noticed that djpeg runs about 15% faster if compiled with -Os > rather than -O4. On x86? On embedded architectures, -O2 is often better than -O3, but if you have a very small instruction cache, -Os could be best. -- Best regards, Denis Oliver Kropp .------------------------------------------. | DirectFB - Hardware accelerated graphics | | http://www.directfb.org/ | "------------------------------------------" _______________________________________________ directfb-dev mailing list [email protected] http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-dev
