I'd like to grab the last frame in a video (.mpg
, .avi
, whatever) and dump it into an image file (.jpg
, .png
, whatever). Toolchain is a modern Linux command-line, so things like mencoder
, transcode
, ffmpeg
&c.
Cheers, Bob.
Use the FFmpeg executable with the seek option. You'll need to convert to a time first, e.g. if I want frame 150 and my video is 29.97 FPS the command will be ffmpeg -ss 00:00:05.01 -i myvideo. avi -frames:v 1 myimage. jpg .
ffmpeg can be used to change the frame rate of an existing video, such that the output frame rate is lower or higher than the input frame rate. The output duration of the video will stay the same.
Use the -t option to specify a time limit: `-t duration' Restrict the transcoded/captured video sequence to the duration specified in seconds. hh:mm:ss[.
This isn't a complete solution, but it'll point you along the right path.
Use ffprobe -show_streams IN.AVI
to get the number of frames in the video input. Then
ffmpeg -i IN.AVI -vf "select='eq(n,LAST_FRAME_INDEX)'" -vframes 1 LAST_FRAME.PNG
where LAST_FRAME_INDEX is the number of frames less one (frames are zero-indexed), will output the last frame.
I have a mp4 / h264 matroska input video file. And none of the above solutions worked for me. (Although I sure they work for other file formats).
Combining samrad's answer above and also this great answer and came up with this working code:
input_fn='output.mp4'
image_fn='output.png'
rm -f $image_fn
frame_count=`ffprobe -v error -count_frames -select_streams v:0 -show_entries stream=nb_read_frames -of default=nokey=1:noprint_wrappers=1 $input_fn`
ffmpeg -i $input_fn -vf "select='eq(n,$frame_count-1)'" -vframes 1 "$image_fn" 2> /dev/null
I couldn't get Nelson's solution to work. This worked for me. https://gist.github.com/samelie/32ecbdd99e07b9d8806f
EDIT (just in case the link disappears, here is the shellscript—bobbogo):
#!/bin/bash
fn="$1"
of=`echo $1 | sed s/mp4/jpg/`
lf=`ffprobe -show_streams "$fn" 2> /dev/null | grep nb_frames | head -1 | cut -d \= -f 2`
rm -f "$of"
let "lf = $lf - 1"
ffmpeg -i $fn -vf select=\'eq\(n,$lf\) -vframes 1 $of
One thing I have not seen mentioned is that the expected frame count can be off if the file contains dupes. If your method of counting frames is causing your image extraction command to come back empty, this might be what is mucking it up.
I have developed a short script to work around this problem. It is posted here.
I found that I had to add -vsycn 2
to get it to work reliably. Here's the full command I use:
ffmpeg -y -sseof -3 -i $file -vsync 2 -update 1 -vf scale=640:480 -q:v 1 /tmp/test.jpg
If you write to a NFS folder then the results will be very inconsistent. So I write to /tmp
then copy the file once done. If it is not done, I do a kill -9
on the process ID.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With