Help with bash array

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1

Hi, I would like to remove audio tracks from several video clips contained in a single directory using the command

files=(*.mpg); ffmpeg -i "${files[@]}" -vcodec copy -an na/output.mpg

I want each processed file outputted to the sub-directory na retaining the original file name, how do I do that? Thank you for reading.

2

Did not test this, but...

ls *mpg | while read a ; do ffmeg -i ${a} -vcodec copy -an na/${a} ; done
3

Or try:

for f in *.mpg
do
  if [ -f "$f" ]; then
    ffmpeg -i "./$f" -vcodec copy -an "na/$f"
  fi
done
4

Thank you, the for loop did the trick! Why do I need the test command?

The while loop produced some strange results. It only processed half the files and gave read/write permissions for output files to root (?)

And, just curious, what is the difference between

while read a; do command $a; done

and

while read a; do command ${a}; done

?

5

You are welcome.. It is there so that if there are no files present there will not be an error message ( in that case $f would get the value "*.mpg" ). The ./ is there to make sure that in case there are file names that start with a minus sign for example, that these cannot be interpreted as a command line option...

There is no difference in this case...