ffmpeg create thumbnail from local or remote video. with Ruby on Rails example.

ffmpeg create thumbnail from local or remote video.
Important point is -ss is before input file. If you place after input file And remote video. create thumbnail will very slow.

local video

$ ffmpeg -ss 5.3 -i "/home/ubuntu/video.mpg" -vframes 1 -f image2 "/home/ubuntu/thumbnail.jpg"

remote video

$ ffmpeg -ss 5.3 -i "http://example.com/video.mpg" -vframes 1 -f image2 "/home/ubuntu/thumbnail.jpg"

Ruby on Rails example

hr = %x[ffmpeg -loglevel error -ss #{m[:time_of]} -i \"#{input_file}\" -y -vframes 1 -vf scale='min(#{size}\\, iw):-1' -f image2 \"#{output_file}\" 2>&1]

• -loglevel error: when error show message.
• -ss: time offset. need before input file
• -i: input file
• -y: force overwrite output file
• -vframe: Set the number of video frames to output. This is an alias for -frames:v
• -vf scale='min(#{size}\\, iw):-1': set thumbnail output size.
• -f image2: For extracting images from a video
• "output_file": thumbnail output file
• 2>&1: return error message