doc/filters: rework and itemize examples for the overlay filter

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Stefano Sabatini 2012-12-15 15:06:01 +01:00
parent bde1e8bf06
commit 35b97ad7c0
1 changed files with 49 additions and 26 deletions

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@ -3214,35 +3214,58 @@ to pass the two inputs through a @var{setpts=PTS-STARTPTS} filter to
have them begin in the same zero timestamp, as it does the example for
the @var{movie} filter.
Follow some examples:
@example
# draw the overlay at 10 pixels from the bottom right
# corner of the main video.
overlay=main_w-overlay_w-10:main_h-overlay_h-10
# insert a transparent PNG logo in the bottom left corner of the input
ffmpeg -i input -i logo -filter_complex 'overlay=10:main_h-overlay_h-10' output
# insert 2 different transparent PNG logos (second logo on bottom
# right corner):
ffmpeg -i input -i logo1 -i logo2 -filter_complex
'overlay=10:H-h-10,overlay=W-w-10:H-h-10' output
# add a transparent color layer on top of the main video,
# WxH specifies the size of the main input to the overlay filter
color=red@@.3:WxH [over]; [in][over] overlay [out]
# play an original video and a filtered version (here with the deshake filter)
# side by side
ffplay input.avi -vf 'split[a][b]; [a]pad=iw*2:ih[src]; [b]deshake[filt]; [src][filt]overlay=w'
# the previous example is the same as:
ffplay input.avi -vf 'split[b], pad=iw*2[src], [b]deshake, [src]overlay=w'
@end example
You can chain together more overlays but the efficiency of such
approach is yet to be tested.
@subsection Examples
@itemize
@item
Draw the overlay at 10 pixels from the bottom right corner of the main
video:
@example
overlay=main_w-overlay_w-10:main_h-overlay_h-10
@end example
Using named options the example above becomes:
@example
overlay=x=main_w-overlay_w-10:y=main_h-overlay_h-10
@end example
@item
Insert a transparent PNG logo in the bottom left corner of the input,
using the @command{ffmpeg} tool with the @code{-filter_complex} option:
@example
ffmpeg -i input -i logo -filter_complex 'overlay=10:main_h-overlay_h-10' output
@end example
@item
Insert 2 different transparent PNG logos (second logo on bottom
right corner) using the @command{ffmpeg} tool:
@example
ffmpeg -i input -i logo1 -i logo2 -filter_complex 'overlay=10:H-h-10,overlay=W-w-10:H-h-10' output
@end example
@item
Add a transparent color layer on top of the main video, WxH specifies
the size of the main input to the overlay filter:
@example
color=red@@.3:WxH [over]; [in][over] overlay [out]
@end example
@item
Play an original video and a filtered version (here with the deshake
filter) side by side using the @command{ffplay} tool:
@example
ffplay input.avi -vf 'split[a][b]; [a]pad=iw*2:ih[src]; [b]deshake[filt]; [src][filt]overlay=w'
@end example
The above command is the same as:
@example
ffplay input.avi -vf 'split[b], pad=iw*2[src], [b]deshake, [src]overlay=w'
@end example
@end itemize
@section pad
Add paddings to the input image, and places the original input at the