Rotating Video Files
Let's see how to rotate a video by 90°. Maybe you recorded a video using your smart phone or digital camera in "portrait" mode, and now you would like to watch it on something other than the phone or camera display. That means that you will need to rotate the video by 90° and probably convert it to DVD format. Here's how to do the needed video rotation and conversion.
I learned how to do this from
However, I have updated a couple of steps described
there to track changes in the
tool, and I have added the steps needed
to turn the result into a DVD.
Rotate the Video
mencoder, part of the
to do this.
The following assumes that
input.avi is the
name of the AVI video file from your camera (change
and that it's 320x240 resolution (seems most common).
Note that I have split all of these long commands into
The backslash character "
"ignore the special meaning of the following character."
So if it is the last character on the line, these
will work as single commands written across multiple lines.
Or you can remove the backslashes and type each as a single
If you type one as a single line with the backslashes
still in place, well, just don't do that.
No good will come of it.
$ mencoder -ovc lavc \ -lavcopts vcodec=mjpeg \ -vf rotate=1 \ -oac copy input.avi -o rotated.avi
Look at the result.
Is it upside down?
Then you need to rotate it 90 degrees in the opposite
rotate=2 in the command:
$ mencoder -ovc lavc \ -lavcopts vcodec=mjpeg \ -vf rotate=2 \ -oac copy input.avi -o rotated.avi
Look at the resulting
rotated.avi and verify
that it's right-side up.
Pad to 4:3 Aspect Ratio
mencoder again to place the tall and narrow
video between black borders, giving you a video stream
of the right orientation and shape.
Change the dimensions as appropriate for the video
file created by your camera!
$ mencoder -ovc lavc \ -lavcopts vcodec=mjpeg \ -vf expand=427:320 \ -oac copy rotated.avi -o padded.avi
Look at the resulting
padded.avi and verify
that it resembles what you would want to see on the TV.
The requested 427x320 is very close to 4:3.
Convert to DVD
This is taken from my page on converting PAL DVDs to NTSC. First, convert to the correct size and frame rate:
$ ffmpeg -i padded.avi \ -target ntsc-dvd \ -s 720x480 \ -r 29.970 my-video-dvd.mpeg
Next, create a new directory and build the DVD file system data structure in it:
$ mkdir my-dvd $ dvdauthor -o my-dvd -t my-video-dvd.mpeg $ dvdauthor -o my-dvd -T
The result is a new directory
containing the DVD-specific subdirectories
ready to be burned onto a DVD with