Goal:

In this blog, we are going to discuss combining 3 videos using the FFmpeg command.

Input:

Process:

Using demuxer

To combine videos run the following command

ffmpeg -y -f concat -safe 0 -i list.txt -c copy -fflags +genpts <output_file_path>

-y: Overwrites the output file if it already exists.

-f concat: Specifies the format as concat for concatenating files.

-safe 0: Allows the use of unsafe file names and paths.

-i list.txt: Specifies the input file list containing the paths of the video files to be concatenated. list.txt is a text file where each line represents a video file path. Make sure to replace list.txt with the actual path and filename of your file list.

-c copy: Indicates that the video and audio streams should be copied from the input files to the output file without any re-encoding.

-fflags +genpts: Sets the flag to generate timestamps for the output video.

<output_file_path>: Specifies the output file name for the concatenated video.

Sample list.txt

file 'D:/files/videos/input_1.mp4'
file 'D:/files/videos/input_2.mp4'
file 'D:/files/videos/input_2.mp4'

For example

ffmpeg -y -f concat -safe 0 -i list.txt -c copy -fflags +genpts combined_output.mp4

Result:

After running the above command combine video will be generated . To check the output file properties run ffprobe <output_file> command

Using concat

ffmpeg -i input_1.mp4 -i input_2.mp4 -i input_3.mp4 -filter_complex "[0:v:0] [0:a:0] [1:v:0] [1:a:0] [2:v:0] [2:a:0]concat=n=3:v=1:a=1 [v] [a]" -map "[v]" -map "[a]" output_combined.mp4

To combine videos run the following command

ffmpeg -y -i <input_video1_path> -i <input_video2_path> -i <input_video3_path> -filter_complex "[0:v:0] [0:a:0] [1:v:0] [1:a:0] [2:v:0] [2:a:0]concat=n=3:v=1:a=1 [v] [a]" -map "[v]" -map "[a]" <output_file_path>

-y: Overwrites the output file if it already exists.

-i <input_video1_path> -i <input_video2_path> -i <input_video3_path>: Specifies the input video files to be concatenated. Replace <input_video1_path>, <input_video1_path>, and <input_video1_path> with the actual path and filenames of your input video files.

-filter_complex: Begins the filter_complex section, which allows complex filtergraphs to be applied.

[0:v:0] [0:a:0] [1:v:0] [1:a:0] [2:v:0] [2:a:0]: Specifies the input streams to be concatenated. [0:v:0] and [0:a:0] represent the video and audio streams from input_1.mp4, [1:v:0] and [1:a:0] represent the video and audio streams from input_2.mp4, and [2:v:0] and [2:a:0] represent the video and audio streams from input_3.mp4.

concat=n=3:v=1:a=1: Applies the concat filter to concatenate the streams. n=3 indicates the number of input streams, v=1 indicates a single video output stream, and a=1 indicates a single audio output stream.

[v] [a]: Specifies the output video and audio streams after concatenation.

-map "[v]" -map "[a]": Maps the concatenated video and audio streams to the output file.

<output_file_path>: Specifies the output file name for the concatenated video.

For example

ffmpeg -i input_1.mp4 -i input_2.mp4 -i input_3.mp4 -filter_complex "[0:v:0] [0:a:0] [1:v:0] [1:a:0] [2:v:0] [2:a:0]concat=n=3:v=1:a=1 [v] [a]" -map "[v]" -map "[a]" output_combined.mp4

After running the above command combine video will be generated . To check the output file properties run ffprobe <output_file> command

How to combine multiple videos using FFmpeg?