问题
I have 2 videos (same resolution, same encoding) files that I want to concat and I want to insert some text for 3 seconds between them, as a splitter. I'm doing this with ffmpeg on Windows.
Optional ideas that I would be interested in:
- avoid reencoding the video in the process
- having a fade in / fade out at the intersection of each part
For now, I made the text as an image (but I am open to other suggestions). Let's say I have:
- video1.mp4: 6:33
- splitter.png (same resolution as video1.mp4)
- video2.mp4: 16:44
I have tried a few things, but I always end up with the same problem: the video is 23:20 (video1 + 3 seconds + video2), but the 3 seconds gap is just the last video1 frame frozen instead of my image/text...
Any Idea what I did wrong or how I should achieve this?
Here is what I tried so far:
Method 1: image to video
Turn the image into a 3 seconds mp4 film, then concat (demuxer) it with the others:
ffmpeg -loop 1 -f image2 -i splitter.png -r 30 -t 3 splitter.mp4
ffmpeg -f concat -i input.txt -codec copy output.mp4
Where the input.txt looks like:
file 'E:\video1.mp4'
file 'E:\splitter.mp4'
file 'E:\video2.mp4'
The content of splitter.png is visible in the splitter.mp4, but not in the output.mp4. Also I'm not entirely sure the splitter.mp4 respects the exact same encoding as the 2 videos, and I don't know how to verify that.
Method 2: insert image frames
Directly run the concat (demuxer) 90 times (30fps -> 3 seconds) on the image
ffmpeg -f concat -i input.txt -codec copy output.mp4
Where the input.txt looks like:
file 'E:\video1.mp4'
file 'E:\splitter.png'
...
file 'E:\splitter.png'
file 'E:\video2.mp4'
Edit: possible solution?
Since all I'm doing is screencasting, I might as well screencast my splitter image. This way I would be sure of the audio & video encoding and wouldn't have any problem merging and it wouldn't need any reencoding... I know it might sound dumb, but it would probably do the trick...
Note: I didn't have try it, since I already worked through Openshot.
回答1:
My guess is this is all a codec issue -- the PNG turned MP4 is probably not the same codec as your real MP4s.
Try this -- concatenation of files of different codecs.
来源：https://stackoverflow.com/questions/18452058/ffmpeg-concat-videos-and-images