I am looking for some tool or program to automatically grab snapshots (a few mins interval) from a video file without display it for me. Mkv support would be nice!
From the ffmpeg manual page http://ffmpeg.org/ffmpeg.html :
For extracting images from a video:
ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
This will extract one video frame per second from the video and will output them in files named ‘foo-001.jpeg’, ‘foo-002.jpeg’, etc. Images will be rescaled to fit the new WxH values.
There are other options for extracting images depending on frame position or time, etc.
Related
I want to record video from a camera, save it to file, and at the same time have access to the last frame recorded.
One idea would be to use ffmpeg's Multiple Outputs functionality where I split the stream into two, one gets saved to file, one spits out the last recorded frame (ideally, the frames won't need to be written to disk, but piped onwards for processing).
What I don't know is how to get ffmpeg to spit "the last frame" from a stream.
Any ideas?
Output a video and continuously update an image every second
ffmpeg -i input.foo outputvideo.mp4 -r 1 -update 1 image.jpg
Output a video and output a new image every second
ffmpeg -i input.foo outputvideo.mp4 -r 1 images_%04d.jpg
Output will be named images_0001.jpg, images_0002.jpg, etc.
Also see
FFmpeg image muxer documentation for more info and options.
How can I extract a good quality JPEG image from a video file with ffmpeg?
I have to create 'preview' on video progress hover. I'm doing with a sprite image and WebVTT file. Using ffmpeg and imagemagick. However generating thumbnails from a mp4 video is really damn slow (20-30 minutes for 2hrs and 20 min long video). The video is Full HD, H246 encoded, 2GB big. The command used
"ffmpeg.exe -i largevideo.mp4 -f image2 -bt 20M -vf fps=1/5 thumbs-%03d.jpg"
Which means thumb for every 5 secs of the video. Is there a way to make it faster? Videos in prod can be even bigger.
OS: Win10, ImageMagick is used later to create the sprite from all the thumbnails created with ffmpeg.
Skip everything except keyframes:
ffmpeg -skip_frame nokey -i input.mp4 -vsync passthrough thumbs-%03d.jpg
Also see:
Get keyframe intervals
Control JPG quality
I'm trying to overlay a video (for example a report) with different other videos or images, like hints to the facebook page or a hint to the website. These other videos or images are smaller than the original and sometimes transparent (rgba).
I already tried to overlay multiple videos, which works pretty well:
ffmpeg -i 30fps_fhd.mp4 -i sample.mp4 -i timer.webm -i logo.jpg -filter_complex "overlay = x=100:y=1000, overlay = x=30:y=66:eof_action=pass, overlay = x=0:y=0" -acodec copy -t 70 out.mp4
But now, I want to start some videos or images not at the beginning of the video, instead after a period of time.
I found flags like 'itsoffset' or 'setpts', but I dont know how to apply them on this 'multiple video / image overlay command'.
LG Bamba
Okay, I found out how it works. I have to take the input with [index:v] apply effects on it (separated with commas) and save it in a variable (add [var-name] at the end of the effect-chain). Then you can apply the overlay effect, by putting two variables (if not edited, then the input variable -> [index:v]) next to each other and write the effect-metadata next to them.
I have a quick time video file, video stream is in motion jpeg format, I extract every frame in the file with
ffmpeg -i a.mov -vcodec copy -f image2 %d.jpg
I found that in every jpeg file, there are actually two FFD8 marker, which means there are actually two images in one single jpeg file.
Is this correct? Is the file interlaced? Anything special need to pass to codec?
Yes, motion Jpeg supports interlaced format. If the jpeg file is half of the full video size, will mean that the mov is interlaced, and you cannot use -vcodec copy to extract the frames. Try ffmpeg -deinterlace or use yadif filter.
I want to create a slideshow of my images with fade in & fade out transitions between them and i am using FFmpeg fade filter.
If I use command:
ffmpeg -i input.mp4 "fade=in:5:8" output.mp4
To create the output video with fade effect, then it gives output video with first 5 frames black and than images are shown with fade in effect but i want fade:in:out effect between frame change.
How can i do that?
Please tell a solution for Centos server because i am using FFmpeg on this server only
To create a video with fade effect, just break the video into parts and create separate videos for each image. For instance, if you have 5 images then firstly, create 50-60 copies of each image and obtain a video for that:
$command= "ffmpeg -r 20 -i images/%d.jpg -y -s 320x240 -aspect 4:3 slideshow/frame.mp4";
exec($command." 2>&1", $output);
This will allow you to create 5 different videos. Then, you need 10-12 different copies of those five images and again create separate videos with fade effects.
ffmpeg -i input.mp4 "fade=in:5:8" output.mp4
After this you will have videos like: video for image 1 and its fade effect then for image 2 and its fade effect and so on. Now combine those videos in respective order to get the whole video.
For combining the videos you need:
$command = "cat pass.mpg slideshow/frame.mpg > final.mpg";
This means to join the videos using cat and then you need to convert them to mpg, join them and again reconvert them to mp4 or avi to view them properly. Also the converted mpg videos will not be proper so do not bother. When you convert them to mp4, it will be working fine.
You can make a slideshow with crossfading between the pictures, by using the framerate filter. In the following example 0.25 is the framerate used for reading in the pictures, in this case 4 seconds for each picture. The parameter fps sets the output framerate. The parameters interp_start and interp_end can be used for changing the fading effect: interp_start=128:interp_end=128 means no fading at all. interp_start=0:interp_end=255 means continuous fading. When one picture has faded out and the next picture has fully faded in, the third picture will immediately begin to fade in. There is no pause for showing the second picture. interp_start=64:interp_end=191 means half of the time is pause for showing the pictures and the other half is fading. Unfortunately it won't be a full fading from 0 to 100%, but only from 25% to 75%. That's not exactly what you might want, but better than no fading at all.
ffmpeg -framerate 0.25 -i IMG_%3d.jpg -vf "framerate=fps=30:interp_start=64:interp_end=192:scene=100" test.mp4
You can use gifblender to create the blended, intermediary frames from your images and then convert those to a movie with ffmpeg.