I have the following command line:
ffmpeg -hide_banner -ss 5 -i test.mp4 -y -vf
"select='eq(pict_type\,PICT_TYPE_I)',
mpdecimate,showinfo,scale=320:240,tile=12x25" -vsync 2 out%%03d.png
As you can see, I make a mosaic of 12x25 (=300) tiles per output image. But I'd like to cap the output to a single image.
Is there a way to have ffmpeg stop processing the video after it found 300 frames?
Additionally, when grabbin the I-frames, is there a way to just keep 1/x for example
After playing with different options, I couldn't find any way to do this.
Use
ffmpeg -hide_banner -ss 5 -skip_frame nokey -i test.mp4 -y -vf "framestep=7,mpdecimate,showinfo,scale=320:240,tile=12x25" -vsync 0 -vframes 1 out.png
framestep value sets x in 1/x. You probably don't need mpdecimate if you're skipping x-1 keyframes. I've added -skip_frame nokey to avoid using the select filter. This method is much faster.
Related
I am trying to extract frames between a certain number as images
Currently I am doing it like this
ffmpeg
-i input.mp4
-vf select='eq(n\,34885)+eq(n\,34886)+eq(n\,34887)+eq(n\,34888)+eq(n\,34889)+eq(n\,34890)+eq(n\,34891)'
-vsync 0 output_frames_%d.png
Not only this the command above very cumbersome but also takes a lot of time to run, is there an easier and faster way to do this?
You may try this
ffmpeg -i input.mp4 -vf "select='between(n\,34885\,34891)'" -vsync 0 -start_number 34885 out-%02d.png
You could try this:
ffmpeg -i input.mp4 -vf select='between(n\,34885\,34891)' -vsync passthrough -frames 7 frame_%d.png
It's less cumbersome and stops once it has hit the target number of frames (7).
I'm trying to use ffmpeg to output all key-frames from a video file and scale them down to 320px wide while maintaining aspect ratio.
I know I could do this with two separate commands but I am trying to find a way to do it tidily in one.
I've already succeeded in each of the steps individually using the following commands.
Output the keyframes:
.\ffmpeg -i input.mp4 -q:v 2 -vf select="eq(pict_type\,PICT_TYPE_I)" -vsync 0 thumb%07d.png
Scale images:
.\ffmpeg -i input.mp4 -vf scale=320:-1 thumb%07d.png
I won't share everything i've tried, but here's three failures at combining them.
//fail, not just keyframes, scaled
.\ffmpeg -i input.mp4 -q:v 2 -vf select="eq(pict_type\,PICT_TYPE_I)" -vsync 0 -vf scale=320:-1 thumb%07d.png -hide_banner
//fail, can't find suitable output format for scale command, invalid argument
.\ffmpeg -i input.mp4 -q:v 2 -vf select="eq(pict_type\,PICT_TYPE_I)" -vsync 0, scale=320:-1 thumb%07d.png -hide_banner
//fail
.\ffmpeg -i input.mp4 -q:v 2 -vf scale=320:-1, -vf select="eq(pict_type\,PICT_TYPE_I)" -vsync 0 thumb%07d.png -hide_banner
I've tried many different things, moving commands, combining using commas etc... But I have not had any success at combining the get key-frames and scale commands.
So how would I go about combining the get key-frames and scale commands so that it works?
thanks.
The select and scale filters here make for a linear sequence of filters, so the are to be specified one after the other. See http://ffmpeg.org/ffmpeg-filters.html#Filtering-Introduction
So, you can use
ffmpeg -i in -vf "select='eq(pict_type\,PICT_TYPE_I)',scale=320:-1" -vsync 0 -q:v 2 out%07d.png
but the below command will be quicker, as it drops non-keyframes at the decoding stage.
ffmpeg -skip_frame nokey -i in -vf "scale=320:-1" -vsync 0 -q:v 2 out%07d.png
I'm trying to extract keyframes from a large video I have. The problem I'm seeing is that it is extracting far too many, leaving me with many very similar images.
Below is what I am currently using (from terminal)
ffmpeg -i video.mov -vf "select=eq(pict_type\,I)" -vsync vfr thumb%04d.png -hide_banner
What would be great is if there was a way I can either make it only output 1 in 5 keyframes. Or what would be even better is if there is a way I can make it only output if the frame is over x% different from the previous one.
1 in 5 keyframes:
ffmpeg -i video.mov -vf "select=eq(pict_type\,I),select='not(mod(n\,5))'" -vsync vfr thumb%04d.png
frame is over x% different from the previous one:
ffmpeg -i video.mov -vf "select=eq(pict_type\,I),select='gt(scene\,x/100)'" -vsync vfr thumb%04d.png
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 am trying to create a video output from multiple video cameras.
Following the example given here Presenting more than 2 videos using FFmpeg
and other similar examples.
but Im getting the error
Output pad "default" for the filter "src" of type "buffer" not connected to any destination
when i run
ffmpeg -i /dev/video1 -i /dev/video0 -filter_complex "[0:0]pad=iw*2:ih[a];[a][1:0]overlay=w[b];[b][2:0]overlay=w:h" -shortest output.mp4
Im not really sure what this means or how to fix it.
Any help would be greatly appreciated!
Thanks.
When using the "padding" option, you have to specify which is the size of the output image and where you want to put the input image
[0:0]pad=iw*2:ih:0:0
tested under windows 7 with file of same size
ffmpeg -i out.avi -i out.avi -filter_complex "[0:0]pad=iw*2:ih:0:0[a];[a][1:0]overlay=w" -shortest output.mp4
and with WebCam Cap (vfwcap) and a still picture (as i have only o=1 WebCam). BTW you can see how to scale one the source to fit in the target (just in case your source have different resolution)
ffmpeg -y -f vfwcap -r 10 -i 0 -loop 1 -i photo.jpg -filter_complex "[0:0]pad=iw*2:ih:0:0[a];[1:0]scale=640:480[b];[a][b]overlay=w" -shortest output.mp4
under Linux:
ffmpeg -i /dev/video1 -i /dev/video0 -filter_complex "[0:0]pad=iw*2:ih:0:0[[a];a][1:0]overlay=w" -shortest output.mp4
if it doesn't work test a simple record of video 1 and after of video 0 and check their properties (type, resolution, fps).
ffmpeg -i /dev/video1 -shortest output1.mp4
ffmpeg -I output1.mp4
If you still have issue, update your question with ffmpeg console output (as text) for video and video 0 capture and also of the call with the overlay