FFmpeg如何拼接视频和output相同的文件前缀

Question

I have a lot of videos cut into three parts, and I want to concat them. I now have the following bash to output videos in the folder to a file named mergedVideo.mp4.

for f in *.mp4 ; do echo file \'$f\' >> fileList.txt;done
ffmpeg -f concat -safe 0 -i fileList.txt -c copy mergedVideo.mp4

All my input files are like Something part1.mp4 , Something part2.mp4 , Something part3.mp4 What I want is to output a file named Something.mp4

It is possible? How can I modify my bash to achieve that~?

Answer 1

Would you please try the following:

#!/bin/bash

pat="^([^[:space:]]+)[[:space:]]*part[[:digit:]]+\.mp4$"
for f in *.mp4; do
    echo file \'$f\' >> fileList.txt
    [[ $f =~ $pat ]] && mergedvideo="${BASH_REMATCH[1]}.mp4"
done
ffmpeg -f concat -safe 0 -i fileList.txt -c copy "$mergedvideo"

Explanation of the regex $pat :

• ^([^[:space:]]+) matches a non-space substring from the beginning of the string $f and is assigned to the shell variable BASH_REMATCH[1] . As for the provided example filenames, BASH_REMATCH[1] will be assigned to Something .
• [[:space:]]* matches a zero or more whitespace(s).
• part[[:digit:]]+ matches a string "part" followed by digit(s).
• \.mp4 matches the suffix.

[Alternative]

If you are familiar with sed as well, the following may be more readable and maintainable:

mergedvideo=$(sed -E 's/[[:space:]]*part[[:digit:]]+//' <<< "$f")

Answer 2

I extend tshiono 's answer to be able to manipulate all the files in the same folders (just like Marinos An mentioned, the idea is to merge files with the same prefix)

Cases like a folder with the following files:

• Monday Blue part1.mp4
• Monday Blue part2.mp4
• Tuesday.mp4
• Wednesday part1.mp4
• Wednesday part2.mp4
• Wednesday part3.mp4

Expected Output:

• Monday Blue.mp4
• Tuesday.mp4
• Wednesday.mp4

#!/bin/bash

pat="^(.+)[[:space:]]+part[[:digit:]]+\.mp4$"
for f in *.mp4; do
    if [[ $f =~ $pat ]]; then
        echo file \'$f\' >> "${BASH_REMATCH[1]}.txt"
    fi
done

for f in *.txt; do
    ffmpeg -f concat -safe 0 -i "${f%%.*}.txt" -c copy "${f%%.*}.mp4"
done