Flip the image

Problem

Flip the video image horizontally and vertically.

Solution

ffmpeg \
    -i input_file \
    -filter:v "hflip, vflip" \
    -c:a copy \
    output_file

Command syntax

ffmpeg
starts the command
-i input_file
path, name and extension of the input file
-filter:v "hflip, vflip"
flips the image horizontally and vertically
-c:a copy
re-encodes using the same audio codec
output_file
path, name and extension of the output file

Discussion

The video filter is specified by -filter:v. We advise to avoid the alias -vfilter and its abbreviation -vf as well. The quotation marks are not mandatory for these video filters, yet we advice to put multiple filters into quotation marks. The quotation marks allow to insert a space between the filters for readability. This filter flips the image horizontally and vertically. By using only one of the parameters hflip or vflip, of course, the image is flipped on that axis only.

The audio codec is specified by -codec:audio, which may be abbreviated as -c:a (or -codec:a or -c:audio). We advise to avoid the alias -acodec. For silent videos you can replace -c:a copy by -an; for video with sound you may choose to re-encode with another audio codec which is allowed by the container.


2018–07–21