ffmpeg in a bash pipe

Question

I have a rmvb file path list, and want to convert this files to mp4 files. So I hope to use bash pipeline to handle it. The code is

Convert() {
    ffmpeg -i "$1" -vcodec mpeg4 -sameq -acodec aac -strict experimental "$1.mp4"
}

Convert_loop(){
    while read line; do
       Convert $line
    done
}

cat list.txt | Convert_loop

However, it only handle the first file and the pipe exits.

So, does ffmpeg affect the bash pipe?

Answer 1

Caveat: I've never used ffmpeg, but in working with other questions concerning the program, it appears that, like ssh, ffmpeg reads from standard input without actually using it, so the first call to Convert is consuming the rest of the file list after read gets the first line. Try this

Convert() {
    ffmpeg -i "$1" -vcodec mpe4 -sameq -acodec aac 
           -strict experimental "$1.mp4" < /dev/null
}

This way, ffmpeg will not "hijack" data from standard input intended for read command.