How can I use the filter twice at different times in FFmpeg?

Tech QnA
1

I want to use multiple filters in one go but confused about how to do it. I searched on the internet and get to know about -vf filter but didn’t get success while using the command. Can someone please help me with this?

2

Welcome back !
You are right, to apply multiple filters in FFmpeg, you can use the -vf (video filtergraph) option multiple times. Each instance of -vf will apply a separate filter.
Here’s an example of how you can apply two filters in FFmpeg:
ffmpeg -i input.mp4 -vf filter1,filter2 output.mp4

3

Thanks,
Can’t we right-write the filters in a separate file and then include that file in the command?

4

Hey 
You can use @ symbol to include the file in the command:
ffmpeg -i input.mp4 -vf @filters.txt output.mp4Where filters.txt contains the filtergraph description, with one filter per line.
For example, the filters.txt file might look like this:
filter1
filter2

You can also specify multiple -vf options in the command line to apply multiple filtergraphs:
ffmpeg -i input.mp4 -vf filter1 -vf filter2 output.mp4This will apply filter1 followed by filter2 to the input video.

5

Is there any order in which the filters will apply?

6

It’s possible to specify the order in which the filters are applied by using the -filter_complex option instead of -vf.
This option allows you to specify the input and output streams for each filter, so you have more control over the order in which the filters are applied.
For example:
ffmpeg -i input.mp4 -filter_complex “[0:v]filter1[temp];[temp]filter2[v]” -map “[v]” output.mp4As per the above example, this will apply filter1 to the input video and save the result to a temporary stream called temp, and then apply filter2 to the temp stream and save the result to the output stream v. The -map option specifies that the output stream v should be used as the video for the output file.