2010/8/14 Dan Dennedy <d...@dennedy.org>: > On Wed, Jul 21, 2010 at 10:51 AM, Simon Eugster <simon...@gmail.com> wrote: >> Dear friends, >> >> I've just added an RGB parade to kdenlive. While testing I found >> something interesting: Although I'm painting on a rect with height 256 >> (as atm we're dealing with 8 bits per channel only) and scaling the >> parade afterwards to the target height, I got kind of scanlines. >> Compare these two images: >> http://granjow.net/uploads/kdenlive/kdenlive-mlt-rgbparade-noeffect.png >> http://granjow.net/uploads/kdenlive/kdenlive-mlt-rgbparade-witheffect.png >> With the MLT effect there are scanlines, without it there are none. >> >> This is quite interesting, as this visualizes how color information >> gets lost when converting between different color spaces (according to >> [1], MLT is using YUV422, the input image is RGB). >> >> Basically I just wanted to show you this because it is interesting. >> But in the long term one of our goals should also be to avoid either >> conversion to other color spaces or the loss of information caused by >> the conversion. > > I just pushed some changes in mlt to fix this problem when using > libswscale - at least on my version. It adds some flags, but some > flags are needed for some color/pixfmts and different flags for > others. Use an incorrect flag, and the results are totally disastrous! > So, I am little worried that it might be version-sensitive. It would > be good if you and others could update mlt from git, test it, and see > if this problem resolves for you without introducing disaster.
By the way, I changed the Histogram and the Waveform to use Rec. 709 by default (can be changed in the context menu). They look much smoother now. :) Simon ------------------------------------------------------------------------------ This SF.net Dev2Dev email is sponsored by: Show off your parallel programming skills. Enter the Intel(R) Threading Challenge 2010. http://p.sf.net/sfu/intel-thread-sfd _______________________________________________ Kdenlive-devel mailing list Kdenlive-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kdenlive-devel
