Unble to create video(.mp4) from images (.jpeg)

Question

When I execute the ffmpeg command I get this error:

Unable to find a suitable output format for ffmpeg

String strCommand = "ffmpeg -loop 1 -t 3 -i " + list.get(0)" -loop 1 -t 3 -i " + list.get(1)+" -loop 1 -t 3 -i " + list.get(2)+" -loop 1 -t 3 -i " + list.get(3)+ " -filter_complex[0:v]trim=duration=3,fade=t=out:st=2.5:d=0.5[v0];[1:v]trim=duration=3,fade=t=in:st=0:d=0.5,fade=t=out:st=2.5:d=0.5[v1];[2:v]trim=duration=3,fade=t=in:st=0:d=0.5,fade=t=out:st=2.5:d=0.5[v2];[3:v]trim=duration=3,fade=t=in:st=0:d=0.5,fade=t=out:st=2.5:d=0.5[v3];[v0][v1][v2][v3]concat=n=4:v=1:a=0,format=yuv420p[v] -map [v] -preset ultrafast " + getVideoFilePath();

Answer 1

You command seems to be ok, please be sure that getVideoFilePath() can get a right path with the supported format, for example, /path/.../slide.mp4, here is a workable example ffmpeg line:

ffmpeg \
-loop 1 -t 3 -i pic001.jpg \
-loop 1 -t 3 -i pic002.jpg \
-loop 1 -t 3 -i pic003.jpg \
-loop 1 -t 3 -i pic004.jpg \
-filter_complex "\
[0:v]trim=duration=3,fade=t=out:st=2.5:d=0.5[v0];\
[1:v]trim=duration=3,fade=t=in:st=0:d=0.5,fade=t=out:st=2.5:d=0.5[v1];\
[2:v]trim=duration=3,fade=t=in:st=0:d=0.5,fade=t=out:st=2.5:d=0.5[v2];\
[3:v]trim=duration=3,fade=t=in:st=0:d=0.5,fade=t=out:st=2.5:d=0.5[v3];\
[v0][v1][v2][v3]concat=n=4:v=1:a=0,format=yuv420p[v]" \
-map "[v]" -preset ultrafast slide.mp4