Hi I am trying to speed up and trim clips with FFMPEG version 4.2.2. Is there a limit to how fast you can speed up a clip? If I try to speed up a clip over a certain then the output file cannot be opened.
I have tried two methods without any luck: 1. using the setPTS filter and 2. inputing the file at a faster frame rate.
1.
ffmpeg -i GH012088.MP4 -y -ss 18 -t 0.48 -an -filter:v "setpts=0.096*PTS" -r 25 output.MP4
2.
ffmpeg -r 312.1875 -i GH012088.MP4 -y -ss 18 -t 0.48 -r 25 -an output.MP4
I am trying to create a clip from the input that starts at 1 second in the original clip, plays at 10.4166 x speed and lasts for 0.48 seconds
What am I doing wrong?
Thanks
Use
ffmpeg -ss 1 -i GH012088.MP4 -y -t 0.48 -an -filter:v "setpts=0.096*PTS" -r 25 output.MP4
The seek has to be on the input side, before frames are retimed. The -t has to be on output side, after frames are retimed.
Does the movie have sound?
If yes, than we have to sync speed up audio and video by combine filter:
ffmpeg -i video.avi -filter_complex "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2.0[a]" -map "[v]" -map "[a]" -f avi video1.avi
Related
I want to take the input, blend N frames, decimate the other frames and use those for the output with the fps of my choice.
I used this line:
ffmpeg -y -i input.mp4 -vf tmix=frames=15:weights="1",select='not(mod(n\,15))' -vsync vfr frames/output-%05d.tif
That generated images, which I combined into the video. So far, so good.
But I'd like to skip the image output and go straight to video, so I tried this:
ffmpeg -y -i input.mp4 -vf tmix=frames=15:weights="1",select='not(mod(n\,15))' -vsync vfr -r 30 -c:v prores_ks -profile:v 3 -vendor apl0 -bits_per_mb 8000 -pix_fmt yuv422p10le output.mov
That produces 1.62 fps video, instead of 30 fps.
I'm at a loss on how to get it to output 30fps without the intermediate step of outputting images.
Thanks
I think the simplest way to achieve this is to feed the input at the 15-times the desired rate and drop all intermediate frames with -r 30:
ffmpeg -y -r 450 -i input.mp4 \
-vf tmix=frames=15:weights="1" \
-r 30 sandbox/out.mp4
However, a tmix solution is somewhat inefficient for your use case because it's mixing for all frames, including those dropped. If you don't mind a longer expression, you can try:
ffmpeg -i in.mp4 \
-vf
setpts=\'floor(N/15)/(30*TB)\',select=\'mod(n,15)+1\':n=15[v0][v1][v2][v3][v4][v5][v6][v7][v8][v9][v10][v11][v12][v13][v14];\
[v0][v1][v2][v3][v4][v5][v6][v7][v8][v9][v10][v11][v12][v13][v14]mix=inputs=15:weights=1 \
-r 30 sandbox/out.mp4
[edit] setpts expression should be floor(N/15)/(30*TB) not mod(n,15)+1 for 15 successive frames to have the same pts.
In my input video is a 48 second range that I wish to speed up. I wish to save only that sped up portion to a new video.
Solution:
ffmpeg -y -ss 00:00:03 -t 00:00:48 -i input.mp4 -an -crf 20 -pix_fmt yuv420p -vf "scale=1080:-1, setpts=PTS/10.0" "output.mp4"
I want to convert video to gif with audio. The two should match when played at the same time.
The command I use somehow generates results that's a bit off.
To create gif:
ffmpeg -ss 00:00:10 -i input.mp4 -t 4 -pix_fmt rgb24 -r 10 -filter:v "scale=-1:300" out.gif
To create mp3:
ffmpeg -ss 00:00:10 -i input.mp4 -t 4 out.mp3
I'm guessing this has something to do with the slicing.
Untested: You could try one of these two options below. If still not working then please provide a short clip (MP4 link) that can be tested to give you required solution...
Option 1) Try using -itsoffset instead of -t...
ffmpeg -ss 00:00:10 -itsoffset 4 -i input.mp4 -pix_fmt rgb24 -r 10 -filter:v "scale=-1:300" out.gif
ffmpeg -ss 00:00:10 -itsoffset 4 -i input.mp4 out.mp3
Option 2) Avoid issue of non-matching times for keyframes (of video track vs audio track)...
First trim the video (get's whatever audio is available at nearest video keyframe to your time):
ffmpeg -ss 00:00:10 -i input.mp4 -t 4 trimmed.mp4
Then use trimmed MP4 (will have synced audio) as source for your output GIF and MP3.
ffmpeg -i trimmed.mp4 -pix_fmt rgb24 -r 10 -filter:v "scale=-1:300" out.mp4
ffmpeg -i trimmed.mp4 out.mp3
I would like to extract, say, 10 video frames from a given video file using ffmpeg, ideally uniformly distributed throughout the video. I know this can be done in a few ways, for example
ffmpeg -i input.mp4 -vf fps=1/10 out%03d.jpg
will output one image every 10 seconds. However, this is too slow for my liking and scales proportionally with the length of the video. I have read a bit about ffmpeg's seeking capability, for example
ffmpeg -ss 00:00:05 -i input.mp4 -frames:v 1 out001.jpg
will very quickly seek to the 5th second of the video and extract one frame. However I haven't come across a way to seek to multiple locations in the video without calling the above command repeatedly at various times.
Is there a quicker way of accomplishing this?
Using a long command, this can be done
e.g.
ffmpeg -ss 00:00:05 -i input.mp4
-ss 00:01:05 -i input.mp4
-ss 00:03:05 -i input.mp4
-ss 00:40:05 -i input.mp4
-map 0:v -frames:v 1 out001.jpg
-map 1:v -frames:v 1 out002.jpg
-map 2:v -frames:v 1 out003.jpg
-map 3:v -frames:v 1 out004.jpg
I want to compress a raw video .y4m to mpg, and I want then to extract the frames from the mpg video, I need the GOP of the compression to be :IBBPBBPBBPBBPBBIBBP....15:2
I used this command:
ffmpeg -i video.ym4 -vcodec libx264 -sameq -y -r 30 output.avi 2>list.txt
ffmpeg -i output.avi -vcodec libx264 -y -sameq -vf showinfo -y -f image2 image%3d.jpeg -r 30 2>list1.txt
The output contains only 2 I frames, 100 P and 198 B frames, it is not 15:2 GOP, what to do?
I need one I-frame every 15 frames, and the pattern to b IBBPBBP..
Sorry, Im new to ffmpeg, please help me, this is the input to my project, it is the important step to me.
Try (according to http://ffmpeg.org/ffmpeg.html#Video-Encoders)
ffmpeg -i video.ym4 -vcodec libx264 -g 15 -y -r 30 output.avi
I think option -sameq (means "same quantizers") is not needed in your case.