[FFMPEG / FFPROBE Notes] Notes on using ffmpeg or ffprobe. #tags: ffmpeg, notes, video

Notes on using ffmpeg or ffprobe.md

Notes on using FFMPEG and FFPROBE

Count frames in a video

Get reported number of frames

Get the reported and actual number of frames in a video.

Note: I recently found a video that reported having 2985 frames, but actually only had 29 frames, which were all keyframes.

ffprobe -v error -select_streams v:0 -show_entries stream=nb_frames -of default=nokey=1:noprint_wrappers=1 <input-video>

Count actual frames

ffprobe -v error -count_frames -select_streams v:0 -show_entries stream=nb_read_frames -of default=nokey=1:noprint_wrappers=1 <input-video>

Count keyframes only

ffprobe -v error -skip_frame nokey -count_frames -select_streams v:0 -show_entries stream=nb_read_frames -of default=nokey=1:noprint_wrappers=1 <input-video>

Links

• Fetch frame count with ffmpeg

Transcode to h264 / MP4

ffmpeg -i <input-video> -c:v libx264 -preset slow -crf 23 -c:a copy <output-video>

Links

• CRF Guide (Constant Rate Factor in x264, x265 and libvpx)

Trim video

Trim out two portions of the video. Keep 8s to 49s and 64s to end:

ffmpeg -i input.mp4 -filter_complex \
"[0:v]trim=start=8:end=49,setpts=PTS-STARTPTS[b]; \
 [0:v]trim=start=64,setpts=PTS-STARTPTS[d]; \
 [b][d]concat[out1]" -map '[out1]' output.mp4

Links

• How can I remove multiple segments from a video using FFmpeg?

where to install ffprobe?