Merge two video clips into one, placing them next to each other

Question

I have two video clips. Both are 640x480 and last 10 minutes. One contains background audio, the other one a singing actor. I would like to create a single 10 minute video clip measuring 1280x480 (in other words, I want to place the videos next to each other and play them simultaneously, mixing audio from both clips). I've tried trying to figure out how to do this with ffmpeg/avidemux, but so far I came up empty. They all refer to concatenating when I search for merging.

Any recommendations?

Answer 1

To be honest, using the accepted answer resulted in a lot of dropped frames for me.

However, using the hstack filter_complex produced perfectly fluid output:

ffmpeg -i left.mp4 -i right.mp4 -filter_complex hstack output.mp4

Answer 2

ffmpeg \
  -i input1.mp4 \
  -i input2.mp4 \
  -filter_complex '[0:v]pad=iw*2:ih[int];[int][1:v]overlay=W/2:0[vid]' \
  -map '[vid]' \
  -c:v libx264 \
  -crf 23 \
  -preset veryfast \
  output.mp4

This essentially doubles the size of input1.mp4 by padding the right side with black the same size as the original video, and then places input2.mp4 over the top of that black area with the overlay filter.

Source: https://superuser.com/questions/153160/join-videos-split-screen

Answer 3

This can be done with just two filters and the audio from both inputs will also be included.

ffmpeg -i left.mp4 -i right.mp4 -filter_complex \
"[0:v][1:v]hstack=inputs=2[v]; \
 [0:a][1:a]amerge[a]" \
-map "[v]" -map "[a]" -ac 2 output.mp4

• hstack will place each video side-by-side.
• amerge will combine the audio from both inputs into a single, multichannel audio stream, and -ac 2 will make it stereo; without this option the audio stream may end up as 4 channels if both inputs are stereo.

Answer 4

ffmpeg -y -ss 0 -t 5 -i inputVideo1.mp4  
-ss 0 -t 5 -i inputVideo2.mp4  
-i BgPaddingImage.jpg  
-filter_complex "nullsrc=size=720*720[base];[base][2:v]overlay=1,format=yuv420p[base1];[0:v]setpts=PTS-STARTPTS,scale=345*700[upperleft];[1:v]setpts=PTS-STARTPTS,scale=345*700[upperright];[base1][upperleft]overlay=shortest=1:x=10:y=10[tmp1];[tmp1][upperright]overlay=shortest=1:x=366:y=10"  
-c:a copy -strict experimental  
-ss 0 -t 5 -preset ultrafast -an 
output.mp4

Add Two Video Side by side And Also Add OverLay Image That Show On Videos Padding With You can change Background Image [BgPaddingImage.jpg] here set your bg image path.

Show This below Video its create from Above command

Answer 5

Gradle Dependency

implementation "com.writingminds:FFmpegAndroid:0.3.2"

Code

Command to concate two videos side by side into one

val cmd : arrayOf("-y", "-i", videoFile!!.path, "-i", videoFileTwo!!.path, "-filter_complex", "hstack", outputFile.path)

Command to append two videos (one after another) into one

  val cmd : arrayOf("-y", "-i", videoFile!!.path, "-i", videoFileTwo!!.path, "-strict", "experimental", "-filter_complex",
                        "[0:v]scale=iw*min(1920/iw\\,1080/ih):ih*min(1920/iw\\,1080/ih), pad=1920:1080:(1920-iw*min(1920/iw\\,1080/ih))/2:(1080-ih*min(1920/iw\\,1080/ih))/2,setsar=1:1[v0];[1:v] scale=iw*min(1920/iw\\,1080/ih):ih*min(1920/iw\\,1080/ih), pad=1920:1080:(1920-iw*min(1920/iw\\,1080/ih))/2:(1080-ih*min(1920/iw\\,1080/ih))/2,setsar=1:1[v1];[v0][0:a][v1][1:a] concat=n=2:v=1:a=1",
                        "-ab", "48000", "-ac", "2", "-ar", "22050", "-s", "1920x1080", "-vcodec", "libx264", "-crf", "27",
                        "-q", "4", "-preset", "ultrafast", outputFile.path)

Note :

"videoFile" is your first video path.
"videoFileTwo" is your second video path.
"outputFile" is your combined video path which is our final output path

To create output path of video

fun createVideoPath(context: Context): File {
        val timeStamp: String = SimpleDateFormat(Constant.DATE_FORMAT, Locale.getDefault()).format(Date())
        val imageFileName: String = "APP_NAME_"+ timeStamp + "_"
        val storageDir: File? = context.getExternalFilesDir(Environment.DIRECTORY_MOVIES)
        if (storageDir != null) {
            if (!storageDir.exists()) storageDir.mkdirs()
        }
        return File.createTempFile(imageFileName, Constant.VIDEO_FORMAT, storageDir)
    }

Code to execute command

try {
            FFmpeg.getInstance(context).execute(cmd, object : ExecuteBinaryResponseHandler() {
                override fun onStart() {

                }

                override fun onProgress(message: String?) {
                    callback!!.onProgress(message!!)
                }

                override fun onSuccess(message: String?) {
                    callback!!.onSuccess(outputFile)
                }

                override fun onFailure(message: String?) {
                    if (outputFile.exists()) {
                        outputFile.delete()
                    }
                    callback!!.onFailure(IOException(message))
                }

                override fun onFinish() {
                    callback!!.onFinish()
                }
            })
        } catch (e: Exception) {
            
        } catch (e2: FFmpegCommandAlreadyRunningException) {
           
        }

Answer 6

Scale the input videos first to make it work for two videos of different height

The following command joins two GIFs side-by-side fixing height 300 px for each:

ffmpeg \
  -i 1.mkv \
  -i 2.mkv \
  -filter_complex '
  [0]scale=-1:300[a];
  [1]scale=-1:300[b];
  [a][b]hstack
  ' \
  12.mkv

If you don't scale the videos to the same height before passing them to hstack then the command fails with:

[Parsed_hstack_0 @ 0x5c75692dda40] Input 1 height 640 does not match input 0 height 480.
[Parsed_hstack_0 @ 0x5c75692dda40] Failed to configure output pad on Parsed_hstack_0
Error reinitializing filters!
Failed to inject frame into filter network: Invalid argument
Error while processing the decoded data for stream #1:0

I've created my test inputs 1.mkv (480x, blue background, 2 seconds) and 2.mkv (640x, green background, 3 seconds) with:

ffmpeg -y -f lavfi -i "
color=blue:480x480:d=2,
drawtext=
  fontcolor=black:
  fontsize=600:
  text='%{eif\:t\:d}':
  x=(w-text_w)/2:
  y=(h-text_h)/2
" 1.mkv
ffmpeg -y -f lavfi -i "
color=green:640x640:d=3,
drawtext=
  fontcolor=black:
  fontsize=800:
  text='%{eif\:t\:d}':
  x=(w-text_w)/2:
  y=(h-text_h)/2
" 2.mkv

The command creates the following processing graph:

1.mkv --> [0] --> scale --> [a] --+
                                  |
                                  v
                                  hstack --> 12.mkv
                                  ^
                                  |
2.mkv --> [1] --> scale --> [b] --+

• first the scale filters modifies the videos to set them to the same height
• then the hstack filter takes those scaled intermediate videos and "horizontally stacks" them

As we can see, if one videos is longer than the other, that command stops the shortest videos at the last frame.

To instead cut off the video to runtime of the shortest video we can add the shortest=1 option of hstack as in:

ffmpeg -y -i 1.mkv -i 2.mkv -filter_complex '[0]scale=-1:300[a];
  [1]scale=-1:300[b];[a][b]hstack=shortest=1' 12-short.mkv

Alternatively, to stack vertically we can use the vstack filter, and fix the video widths rather than heights:

ffmpeg -y -i 1.mkv -i 2.mkv -filter_complex '[0]scale=300:-1[a];
  [1]scale=300:-1[b];[a][b]vstack' 12-vert.mkv

All the above commands also just work if you change .mkv for .gif which is how I generated the images for this answer.

Tested on Ubuntu 23.10, ffmpeg 6.0.