Added simple motion detect filter.

This filter uses a description file which follows this format :
x1,y1,x2,y2,level,downspeed,upspeed,mrl
...
where x1,y1,x2,y2 describe a sensible rectangle, level is the minimum difference for an active pixel, downspeed an upspeed are to integers.
mrl is a mrl to go when the filter has detected movement in the rectangle.

This is fun with vlm. For example, you should try to launch vlc normaly with vlm and then type :
new camera broadcast
setup camera enabled
setup camera input mrl to your camera
setup camera option filter=motiondetect,transform
#setup camera option transform-type=vflip
#indeed, I did not reach to make this working
control camera play

Have fun ;)

configure.ac

@@ -947,7 +947,7 @@ dnl
 VLC_ADD_PLUGINS([dummy rc telnet logger gestures memcpy hotkeys netsync showintf])
 VLC_ADD_PLUGINS([mpgv mpga m4v m4a h264 ps pva avi asf aac mp4 rawdv nsv real aiff mjpeg demuxdump])
 VLC_ADD_PLUGINS([cvdsub svcdsub spudec subsdec dvbsub mpeg_audio lpcm a52 dts cinepak])
-VLC_ADD_PLUGINS([deinterlace invert adjust wall transform distort clone crop motionblur])
+VLC_ADD_PLUGINS([deinterlace invert adjust wall transform distort clone crop motionblur motiondetect])
 VLC_ADD_PLUGINS([float32tos16 float32tos8 float32tou16 float32tou8 a52tospdif dtstospdif fixed32tofloat32 fixed32tos16 s16tofixed32 s16tofloat32 s16tofloat32swab s8tofloat32 u8tofixed32 u8tofloat32 audio_format])
 VLC_ADD_PLUGINS([trivial_resampler ugly_resampler linear_resampler bandlimited_resampler])
 VLC_ADD_PLUGINS([trivial_channel_mixer simple_channel_mixer headphone_channel_mixer normvol])

modules/video_filter/Modules.am

@@ -12,4 +12,5 @@ SOURCES_blend = blend.c
 SOURCES_scale = scale.c
 SOURCES_time = time.c
 SOURCES_marq = marq.c
+SOURCES_motiondetect = motiondetect.c
 noinst_HEADERS += filter_common.h