Read a video stream from a movie container.
It accepts the syntax: movie_name[:options] where movie_name is the name of the resource to read (not necessarily a file but also a device or a stream accessed through some protocol), and options is an optional sequence of key=value pairs, separated by ":".
The description of the accepted options follows.
- format_name, f
-
Specifies the format assumed for the movie to read, and can be either the name of a container or an input device. If not specified the format is guessed from movie_name or by probing.
- seek_point, sp
-
Specifies the seek point in seconds, the frames will be output starting from this seek point, the parameter is evaluated with
av_strtod
so the numerical value may be suffixed by an IS postfix. Default value is "0". - stream_index, si
-
Specifies the index of the video stream to read. If the value is -1, the best suited video stream will be automatically selected. Default value is "-1".
This filter allows to overlay a second video on top of main input of a filtergraph as shown in this graph:
input -----------> deltapts0 --> overlay --> output ^ | movie --> scale--> deltapts1 -------+
Some examples follow:
# skip 3.2 seconds from the start of the avi file in.avi, and overlay it # on top of the input labelled as "in". movie=in.avi:seek_point=3.2, scale=180:-1, setpts=PTS-STARTPTS [movie]; [in] setpts=PTS-STARTPTS, [movie] overlay=16:16 [out] # read from a video4linux2 device, and overlay it on top of the input # labelled as "in" movie=/dev/video0:f=video4linux2, scale=180:-1, setpts=PTS-STARTPTS [movie]; [in] setpts=PTS-STARTPTS, [movie] overlay=16:16 [out]