Attached a patch which adds a "blend" parameter to the framestep filter, to blend frames together at each step, for a motion blur effect. The number of frames that are blended (i.e. the exposure time, in frames) can be controlled, allowing control over the strength of the motion blur. The filter has timeline support, and supports both 8-bit and 16-bit pixel formats. Tests and documentation included.
Note that a similar effect is already possible by repeatedly chaining the tblend and framestep=step=2 filters; see for example: https://video.stackexchange.com/questions/16552/4x-resample-videoframes-using-ffmpeg But this is limited to steps that are powers of two, and this does not allow an intermediate exposure time. It's also slower. The main use I've had for the attached patch myself is to blend down rendered high framerate footage to get a high quality motion blur effect. Matthias C. M. Troffaes (1): vf_framestep: add blend parameter for motion blur effect Changelog | 1 + doc/filters.texi | 7 ++ libavfilter/vf_framestep.c | 242 ++++++++++++++++++++++++++++++++++---- tests/fate/filter-video.mak | 5 + tests/ref/fate/filter-framestep-1 | 17 +++ tests/ref/fate/filter-framestep-2 | 17 +++ tests/ref/fate/filter-framestep-3 | 17 +++ 7 files changed, 286 insertions(+), 20 deletions(-) create mode 100644 tests/ref/fate/filter-framestep-1 create mode 100644 tests/ref/fate/filter-framestep-2 create mode 100644 tests/ref/fate/filter-framestep-3 -- 2.7.4 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel