Hey all this command works fine for me while extracting keyframes : ffmpeg -vf select="eq(pict_type\,PICT_TYPE_I)" -i yourvideo.mp4 -vsync 2 -s 160x90 -f image2 thumbnails-%02d.jpeg.
I was just wondering if someone knows what will work with this to restrict the number of keyframes to say,200. Thanks.
You can add -vframes 200 as an output option.
Related
Using FFMPG I'm creating a poster image from a video and adding an watermark/overlay to the poster. The following works great with small video files, but destroys my CPU with 1080p files.
ffmpeg -ss 15 -i preview.mp4 -i play-button.png \
-filter_complex overlay='(main_w-overlay_w)/2:(main_h-overlay_h)/2', \
scale='min(640\, iw):-1' -vframes 1 poster.jpg
Is there any way to speed this up? Or should I look to another solution for the overlay?
My solution is similar yours. But i use -s to set the output resolution for the image, and -f image2 for rendering. This commands works fine for me:
ffmpeg -ss 15 -i preview.mp4 -i play-button.png -filter_complex "overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2" -vframes 1 -s 640x360 -f image2 -y poster.jpg
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.
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
Can someone please tell me what I'm doing wrong?
I'm using the following arguments to watermark a video with ffmpeg from a c# app:
-i "video.AVI" -s 384x288 -vhook "vhook/imlib2.dll -x 0 -y 0 -i
"watermark.png"" -y "output.avi"
-sameq
The orginal file size is 233mb but the output is 60 odd mb. I thought using the -sameq argument would give me the same size and quality output.
Instead of -sameq try defining the bitrates manually with -ab and -vb.
I currently have a jpeg file which I converted to an flv using the following command:
ffmpeg -r 10 -b 180000 -i test.jpg test.mp4
Now, I want to increase the duration of this .mp4 clip, so the picture stays on the screen for more than a split second. Eventually, I hope to merge a stream of these files to create a slide show out of jpeg files.
Does anyone know how to increase the duration of a clip in ffmpeg?
Looping the input and setting a duration should achieve the effect you want:
ffmpeg -loop_input -i test.jpg -t 10 test.mp4
Doing something like this should work (at least for a single image):
ffmpeg -loop_input -i picture.jpg -r 1 -vcodec flv -b 192k -i Music.mp3 -acodec copy -shortest output.flv
I bet you could get it working with multiple images by adding more inputs though I haven't tested.
(http://forum.videohelp.com/threads/280695-FFMPEG-Loop-input-video)