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--- rescale_video [2017/08/17 18:08] – created walkeradmin
+++ rescale_video [2017/08/17 18:14] (current) – walkeradmin
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 ====== Rescale Video ======
+<color #db5f0b>Aug 2017</color>
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+----
+As well as transcoding video, we can rescale video, handy for converting HD to SD or UHD to HD. Rescaling can be done when transcoding, or as a step on its own. Please note, if you want to play video back at a certain size, ffplay can rescale the output video, without destroying the source.
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+----
+This is how to rescale the video, where you specify the framesize:
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+    ffmpeg -i input.mov -vf scale=320:240 output.mov
+\\
+----
+You can also rescale without specifying the exact aspect ratio, so here we have specified the width, and the height will be worked out automatically from the original aspect ratio.
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+    ffmpeg -i input.mp4 -vf scale=320:-1 output.mp4
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+\\
+----
+To transcode and rescale in one go, you can use the following example:
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+    ffmpeg -i source.mov -vcodec h264 -b:v 50M -vf scale=960:540 dest.mp4
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+\\