$ sudo pacman -S openshot
resolving dependencies...
warning: cannot resolve "libavcodec.so=57-64", a dependency of "libquicktime" 
warning: cannot resolve "libswscale.so=4-64", a dependency of "libquicktime" 
warning: cannot resolve "libquicktime", a dependency of "dvgrab" 
warning: cannot resolve "dvgrab", a dependency of "openshot" 
:: The following package cannot be upgraded due to unresolvable dependencies:
      openshot

building libquicktime fails with:

In file included from lqt_ffmpeg.c:32:
params.h:152:33: error: ‘FF_MAX_B_FRAMES’ undeclared here (not in a function); did you mean ‘PARAM_MAX_B_FRAMES’?
     .val_max =     { .val_int = FF_MAX_B_FRAMES }, \
                                 ^~~~~~~~~~~~~~~
lqt_ffmpeg.c:108:3: note: in expansion of macro ‘PARAM_MAX_B_FRAMES’
   PARAM_MAX_B_FRAMES, \
   ^~~~~~~~~~~~~~~~~~
lqt_ffmpeg.c:196:3: note: in expansion of macro ‘ENCODE_PARAM_VIDEO_FRAMETYPES_IPB’
   ENCODE_PARAM_VIDEO_FRAMETYPES_IPB,
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lqt_ffmpeg.c: In function ‘ffmpeg_map_init’:
lqt_ffmpeg.c:934:3: warning: ‘avcodec_register_all’ is deprecated [-Wdeprecated-declarations]
   avcodec_register_all();
   ^~~~~~~~~~~~~~~~~~~~
In file included from ffmpeg.h:29,
                 from lqt_ffmpeg.c:31:
/usr/include/libavcodec/avcodec.h:4086:6: note: declared here
 void avcodec_register_all(void);
      ^~~~~~~~~~~~~~~~~~~~
make[3]: *** [Makefile:407: lqt_ffmpeg.lo] Error 1
make[3]: Leaving directory '/home/freemor/build/abs/libquicktime/src/libquicktime-1.2.4/plugins/ffmpeg'
make[2]: *** [Makefile:371: all-recursive] Error 1
make[2]: Leaving directory '/home/freemor/build/abs/libquicktime/src/libquicktime-1.2.4/plugins'
make[1]: *** [Makefile:444: all-recursive] Error 1
make[1]: Leaving directory '/home/freemor/build/abs/libquicktime/src/libquicktime-1.2.4'
make: *** [Makefile:351: all] Error 2
==> ERROR: A failure occurred in build().
    Aborting...