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@@ -14,18 +14,6 @@ |
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Libavfilter is the filtering API of Libav. It is the substitute of the |
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now deprecated 'vhooks' and started as a Google Summer of Code project. |
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Integrating libavfilter into the main Libav repository is a work in |
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progress. If you wish to try the unfinished development code of |
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libavfilter then check it out from the libavfilter repository into |
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some directory of your choice by: |
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@example |
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svn checkout svn://svn.libav.org/soc/libavfilter |
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@end example |
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And then read the README file in the top directory to learn how to |
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integrate it into ffmpeg and avplay. |
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But note that there may still be serious bugs in the code and its API |
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and ABI should not be considered stable yet! |
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@@ -48,15 +36,14 @@ and the vflip filter before merging it back with the other stream by |
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overlaying it on top. You can use the following command to achieve this: |
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@example |
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./ffmpeg -i in.avi -s 240x320 -vf "[in] split [T1], fifo, [T2] overlay= 0:240 [out]; [T1] fifo, crop=0:0:-1:240, vflip [T2] |
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./avconv -i input -vf "[in] split [T1], fifo, [T2] overlay=0:H/2 [out]; [T1] fifo, crop=iw:ih/2:0:ih/2, vflip [T2]" output |
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@end example |
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where input_video.avi has a vertical resolution of 480 pixels. The |
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result will be that in output the top half of the video is mirrored |
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The result will be that in output the top half of the video is mirrored |
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onto the bottom half. |
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Video filters are loaded using the @var{-vf} option passed to |
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ffmpeg or to avplay. Filters in the same linear chain are separated by |
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avconv or to avplay. Filters in the same linear chain are separated by |
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commas. In our example, @var{split, fifo, overlay} are in one linear |
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chain, and @var{fifo, crop, vflip} are in another. The points where |
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the linear chains join are labeled by names enclosed in square |
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