本文介绍了使用FFmpeg进行视频处理的各种技巧，包括视频合并、裁剪、速度调整、添加文字和图片等操作的具体命令示例。
http://corpus.hubwiz.com/2/node.js/19154807.html
Merging two video streams and saving as one file
I'm writing chat application with video call using webRTC. I have two MediaStreams, remote and local and want to merge and save them as one file. So when opening a file, i shall see large video frame (remote stream) and little video frame at top right (local stream). Now I can record these two streams separately using RecordRTC. How can i merge them with nodejs? (no code because I don't know how it's done)
- node.js
- video-streaming
- webrtc
You can use FFmpeg with -filter_complex, here is a working and tested example using FFmpeg version N-62162-gec8789a:
ffmpeg -i main_video.mp4 -i in_picture.mp4 -filter_complex "[0
0]scale=640x480[main_video]; [10]scale=240x180[in_picture];[main_video][in_picture]overlay=390:10" output.mp4
So, this command tells FFmpeg to read from two input files, main_video.mp4 and in_picture.mp4, then it send some information to the-filter_complex flag...
The -filter_complex flag takes the [0 (first input, first video track) and scale this video to be 640x480px and it identifies the video as 0][main_video], then, takes the [1 (second input, video track 0) and resize the video to 240x180px naming the video0][in_picture], then it merges both videos making an overlay of the second one at x=390 y=10.
Then it saves the output to output.mp4
It is that what you want?
UPDATE: I forgot to add, all you need in node is a module to run FFmpeg, there are plenty of those: https://nodejsmodules.org/tags/ffmpeg
1/4 every video, use first audio
ffmpeg -i vod1.flv -i vod2.flv -i vod3.flv -i vod4.flv -filter_complex "[0:v]pad=iw*2:ih*2[a];[a][1:v]overlay=w[b];[b][2:v]overlay=0:h[c];[c][3:v]overlay=w:h" out0080.flv
ok:mux multi font
ffmpeg -i src.mp4 -vf "drawtext=fontfile=/usr/share/fonts/truetype/droid/DroidSansMono.ttf : fontcolor=white : text='Suker-10-10' : x=10: y=10, drawtext=fontfile=/usr/share/fonts/truetype/droid/DroidSansMono.ttf : fontcolor=white : text='Suker10-100' : x=10: y=100, drawtext=fontfile=/usr/share/fonts/truetype/droid/DroidSansMono.ttf : fontcolor=white : text='Suker10-200' : x=10: y=200" -an -y outfont.mp4
mux two video
ffmpeg -i 01.mp4 -i mvp.mp4 -filter_complex "[0:v]format=rgb24,setsar=sar=1/1[mv];[1:v]format=rgb24,setsar=sar=1/1[in];[in][mv]blend=all_mode='addition':all_opacity=1,format=rgb24" -strict -2 output.mp4
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ffmpeg -i out0102.mp4 -i nicepass.mp4 -filter_complex "[0:v]scale=640x360,format=rgb24,setsar=sar=1/1[mv];[1:v]scale=640x360,format=rgb24,setsar=sar=1/1[in];[in][mv]blend=all_mode='addition':all_opacity=1,format=rgb24" -strict -2 output-2116-nicepass.mp4
Create a file mylist.txt with all the files you want to have concatenated in the following form (lines starting with a # are ignored):
# this is a comment
file '/path/to/file1'
file '/path/to/file2'
file '/path/to/file3'ffmpeg -f concat -i mylist.txt -c copy outputwiki:
How to speed up
/
slow down a video
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Speeding up/slowing down video
You can change the speed of a video stream using the setpts video filter. Note that in the following examples, the audio stream is not changed, so it should ideally be disabled with -an.
To double the speed of the video, you can use:
ffmpeg -i input.mkv -filter:v "setpts=0.5*PTS" output.mkv
The filter works by changing the presentation timestamp (PTS) of each video frame. For example, if there are two succesive frames shown at timestamps 1 and 2, and you want to speed up the video, those timestamps need to become 0.5 and 1, respectively. Thus, we have to multiply them by 0.5.
Note that this method will drop frames to achieve the desired speed. You can avoid dropped frames by specifying a higher output frame rate than the input. For example, to go from an input of 4 FPS to one that is sped up to 4x that (16 FPS):
ffmpeg -i input.mkv -r 16 -filter:v "setpts=0.25*PTS" output.mkv
To slow down your video, you have to use a multiplier greater than 1:
ffmpeg -i input.mkv -filter:v "setpts=2.0*PTS" output.mkv
Speeding up/slowing down audio
You can speed up or slow down audio with the atempo audio filter. To double the speed of audio:
ffmpeg -i input.mkv -filter:a "atempo=2.0" -vn output.mkv
The atempo filter is limited to using values between 0.5 and 2.0 (so it can slow it down to no less than half the original speed, and speed up to no more than double the input). If you need to, you can get around this limitation by stringing multiple atempo filters together. The following with quadruple the audio speed:
ffmpeg -i input.mkv -filter:a "atempo=2.0,atempo=2.0" -vn output.mkv
Using a complex filtergraph, you can speed up video and audio at the same time:
ffmpeg -i input.mkv -filter_complex "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2.0[a]" -map "[v]" -map "[a]" output.mkv//替换音频
./ffmpeg -i 720p.mp4 -c:v copy -an -y outTemp.mp4
./ffmpeg -i outTemp.mp4 -i ./music1.acc -y outMusic.mp4
//添加字幕,随机显示
./ffmpeg -y -i 720p.mp4 -acodec copy -ac 2 -vcodec libx264 -refs 2 -x264opts keyint=150:min-keyint=15 -vf "drawtext=fontfile=./FZZYJW.ttf: fontsize=30:text='动云动云动云':x=if(eq(mod(t\,3)\,0)\,rand(0\,(w-text_w))\,x):y=if(eq(mod(t\,3)\,0)\,rand(0\,(h-text_h))\,y)" drawtext1-1.mp4
//加入时间，时间显示有问题，好几秒后秒表才加1.
./ffmpeg -i 720p.mp4 -vf "drawtext='fontfile=./FZZYJW.ttf: text=%{localtime\:%T}': r=25: x=(w-tw)/2: y=h-(2*lh): fontcolor=white: box=1: boxcolor=0x00000000@1" -vcodec libx264 720_time333.mp4
0 17:46:49
./ffmpeg -i 720p.mp4 -sws_dither auto -c:v libx264 720_dou.mp4 //抖动无效
0 17:47:38
./ffmpeg -i 720p.mp4 -sws_dither bayer -c:v libx264 720_dou.mp4 //抖动无效
add time second
ffmpeg -i 01.mp4 -vf "drawtext=fontfile=/usr/share/fonts/truetype/droid/DroidSansMono.ttf : fontcolor=white : timecode='00\:00\:00\:00': r=50: text='SukerTime': x=10: y=10: box=1: boxcolor=0x00000000@1" -an -y outfont-`date +%H%M%S`.mp4
http://ffmpeg.org/pipermail/ffmpeg-user/2013-January/012964.html
overlay and drawtext
ffmpeg -y -i 01.mp4 -i htlogo.png -filter_complex "[0][1]overlay[b];[b] drawtext=fontfile=/Windows/Fonts/arialbd.ttf:text=mytexte :fontsize=46:fontcolor=white:shadowcolor=black:shadowx=1:shadowy=1:x=W*(1-0.05*t):y=H+descent-ascent" -an mix-`date +%H%M%S`.mp4
ffmpeg -f image2 -i image1.jpg video.mpg
ffmpeg -i video.mpg -i audio.mp3 -acodec copy -vcodec copy newvideo.avi
ffmpeg -i image.jpg -i audio.mp3 -acodec copy -vcodec mpeg4 newvideo.mp4
- overlay=x='if(gte(t,2), -w+(t-2)*20, NAN)
- ffmpeg -i ~/Movies/objectC/bbs.chinaffmpeg.com-孙悟空.mp4 -i ~/Movies/guanlangaoshou.mp4 -vcodec libx264 -an -filter_complex "overlay=x='if(gte(t,2), -w+(t-2)*20, NAN)':y=0" -s 320x240 output.mp4
ffmpeg -i 01.mp4 -vf drawtext="text='top-->bottom':fontsize=100:fontcolor=red:y=50*t" -an out-top-bottom.mp4
ffmpeg -i 01.mp4 -vf drawtext="text='bottom-->top':fontsize=100:fontcolor=red:y=h-30*t-text_h" -an out-bottom-top.mp4
ffmpeg -i 01.mp4 -vf drawtext="text='left-->right':fontsize=100:fontcolor=red:x=50*t" -an out-left-right.mp4
ffmpeg -i 01.mp4 -vf drawtext="text='right-->left':fontsize=100:fontcolor=red:x=w-50*t-text_w" -an out-right-left.mp4
ffmpeg -i 01.mp4 -vf "drawtext=enable='between(t,0,75)':fontsize=100:fontcolor=white:x=10:y=10:text='Test Text', drawtext=enable='between(t,75,150)':fontsize=100:fontcolor=white:x=10:y=10:text='00000000'" -acodec copy `date +%Y%m%d_%H%M%S`.mp4
this command ok
ffmpeg version 3.0.2-static
ffmpeg -y -i 01.mp4 -vf "drawbox=enable='between(t,2,6)':y=ih-ih/4:color=black@0.5:width=iw:height=56:t=max",\ "drawtext=enable='between(t,2,6)':fontfile=roboto.ttf:y=h-h/4+10:x=20:text='Test Heading':fontcolor=white:fontsize=16,drawtext=enable='between(t,2,6)':fontfile=roboto.ttf:y=h-h/4+30:x=20:text='Test sub heading':fontcolor=white:fontsize=12" -acodec copy `date +%Y%m%d_%H%M%S`.mp4
ffmpeg -i 01.mp4 -vf "drawtext=enable='between(t\,0\,5)':fontsize=100:fontcolor=white:x=10:y=10:text='Test Text', drawtext=enable='between(t\,5\,8)':fontsize=100:fontcolor=white:x=10:y=10:text='00000000'" -acodec copy `date +%Y%m%d_%H%M%S`.mp4
ffmpeg -i 01.mp4 -i liveLogo.png -filter_complex "[1:0] zoompan=z='zoom+0.005':s=640x360:d=120 [mapImage],[0:v][mapImage] overlay=main_w/2-overlay_w/2:main_h/2-overlay_h/2:enable='between(t,0,10)'" -y png_zoompan.mp4
扫一扫
477
到【灌水乐园】发言
fmpeg -i vod1.flv -i vod2.flv -filter_complex "[0
0]scale=720x480[main_video]; [1
0]scale=700x450[in_picture];[main_video][in_picture]overlay=10:10" out05231943.flv
vod2 over vod1 with postion 10,10