Using FFMPEG to extract multichannel audio from Quicktime - audio

So I have a quicktime file with proxy video content and 8 audio tracks. I need to extract the audio into a single multichannel wave file. I think this is probably pretty simple, but I can't find the solution.
What I have:
ffmpeg -i input.mov -c:a copy output.wav
This gives me just a single channel, so there must be some mapping issue going on.

Without -map, ffmpeg will pick one audio stream from among all inputs for output.
You need to specify multiple outputs and map one stream per output.
ffmpeg -i input.mov
-map 0:a:0 -c:a copy stream0.wav
-map 0:a:1 -c:a copy stream1.wav
-map 0:a:2 -c:a copy stream2.wav
-map 0:a:3 -c:a copy stream3.wav
-map 0:a:4 -c:a copy stream4.wav
-map 0:a:5 -c:a copy stream5.wav
-map 0:a:6 -c:a copy stream6.wav
-map 0:a:7 -c:a copy stream7.wav
Command shown on multiple lines for clarity.
For a single multichannel output, you have to first merge the streams.
ffmpeg -i input.mov -filter_complex "[0:a:0][0:a:1][0:a:2][0:a:3][0:a:4][0:a:5][0:a:6][0:a:7]amerge=8" multichannel.wav

Related

Why is adding background music to video using `ffmpeg -i input.mp4 -i music.mp3 output.mp4` not working?

I explored google and StackOverflow for how to add background music to the video and many of them suggested to use
ffmpeg -i input.mp4 -i audio.mp3 -shortest output.mp4
I have been trying to achieve this but it just does not work. When I try to add map like
ffmpeg -i "input.mp4" -i bg.mp3 -map 0:v:0 -map 1:a:0 oo.mp4
The video sound is replaced by the bg.mp3
And if I try -map 0 -map 1:a:0 or not provide map, the audio is not added at all.
How do I add the background music? I don't also get any error.
-map is a selector; select a type of stream from an input "file". To merge two audio streams, you need an audio filter:
ffmpeg -i input.mp4 -i audio.mp3 -lavfi "[0:a][1:a]amerge[out]" -map 0:v -map [out]:a -shortest output.mp4
-lavfi: Same as -filter_complex, because you have two inputs
[0:a][1:a] take audio stream from the first and second inputs
-map 0:v select the video stream from the first input without processing
-map [out]:a select the audio stream from the filtergraph (processed)
The shortest option in the amerge filter is set by default.
If you have problems, you might want to check also the amix filter, the audio codecs of your files, and the volume filter to adjust the volume of the inputs in the filtergraph.
Additional references:
https://ffmpeg.org/ffmpeg-filters.html#amerge
https://ffmpeg.org/ffmpeg-filters.html#amix
https://ffmpeg.org/ffmpeg-filters.html#volume
If the video length is longer than music you can add "-stream_loop -1" to repeat music until end of video
ffmpeg -i video_with_audio.mkv -stream_loop -1 -i background_music.mp3 -lavfi "[0:a][1:a]amerge[out]" -map 0:v -map [out]:a -shortest video_with_audio_and_background_music.mkv
If you want increase or decrease the volume, follow this command:
ffmpeg -i video_with_audio.mkv -stream_loop -1 -i background_music.mp3 -lavfi "[1:a]volume=0.2,apad[A];[0:a][A]amerge[out]" -map 0:v -map [out]:a -shortest video_with_audio_and_background_music.mkv

Merging 2 audios files with a video in ffmpeg

I'm trying to merge 2 audio files (.wav with video file .mp4) to produce the output in video.mp4 extension using ffmpeg on Windows CMD.
This is what I have tried :
ffmpeg -i V.MP4 -i A1.WAV -i A2.WAV -map 0:v -map 1:a -map 2:a -c:v copy -vcodec copy Output.MP4
The CMD output for that is :
This command will output the Output.mp4 file but it will merge the video with only 1 of the audio files which is A2.wav and ignores the other audio file A1.wav
I want to merge without re-encoding or any offset, just merging the 3 files as they are in a file one .mp4 file.
I checked some topics here in stackoverflow like this and this but they didn't help.
In order to mixdown the audio, you should use the amix filter
ffmpeg -i V.MP4 -i A1.WAV -i A2.WAV -filter_complex "[1][2]amix=inputs=2[a]" -map 0:v -map "[a]" -c:v copy Output.MP4

Singler line FFMPEG cmd to Merge Video /Audio and retain both audios

I have a project that requires merging of a video file with another audio file. The expected out put is an video file that will have both the audio from actual video and the merged audio file. The length of the output video file will be same to the size of the actual video file.
Is there a single line FFMPEG command to achieve this using copy and -map parameters ?
The video form I will be using is either flv or mp4
And the audio file format will be mp3
There can be achieved without using map also.
ffmpeg -i video.mp4 -i audio.mp3 output.mp4
In case you want the output.mp4 to stop as soon as one of the input stops (audio/video)
then use
-shortest
For example: ffmpeg -i video.mp4 -i audio.mp3 -shortest output.mp4
This will make sure that the output stops as and when any one of the inputs is completed.
Since you have asked that you want to do it with map. this is how you do it:
ffmpeg -i video.mp4 -i audio.mp3 -map 0:0 -map 1:0 -shortest output.mp4
Now, since you want to retain the audio of the video file, consider you want to merge audio.mp3 and video.mp4. These are the steps:
Extract audio from the video.mp4
ffmpeg -i video.mp4 1.mp3
Merge both audio.mp3 and 1.mp3
ffmpeg -i audio.mp3 -i 1.mp3 -filter_complex amerge -c:a libmp3lame -q:a 4 audiofinal.mp3
Remove the audio from video.mp4 (this step is not required. but just to do it properly)
ffmpeg -i video.mp4 -an videofinal.mp4
Now merge audiofinal.mp3 and videofinal.mp4
ffmpeg -i videofinal.mp4 -i audiofinal.mp3 -shortest final.mp4
note: in the latest version of ffmpeg it will only prompt you to use '-strict -2' in case it does then use this:
ffmpeg -i videofinal.mp4 -i audiofinal.mp3 -shortest -strict -2 final.mp4
hope this helps.
You can not do that using one cmd.
1. Get the audio from video file, the audio file name is a.mp3
ffmpeg.exe -i video.mp4 a.mp3
2. Merge two audio files(audio.mp3+a.mp3=audiofinal.mp3)
ffmpeg.exe -i audio.mp3 -i a.mp3 -filter_complex amerge -c:a libmp3lame -q:a 4 audiofinal.mp3
3. Merge video file and audio file(video.mp4+audiofinal.mp3=output.mp4)
ffmpeg.exe -i video.mp4 -i audiofinal.mp3 -map 0:v -map 1:a -c copy -y output.mp4
I don't think extracting the audio from the video is necessary. We can just use -filter_complex amix to merge both audios:
ffmpeg -i videowithaudio.mp4 -i audiotooverlay.mp3 -filter_complex amix -map 0:v -map 0:a -map 1:a -shortest videowithbothaudios.mp4
-filter_complex amix overlays the audio from the first input file on top of audio in the second input file.
-map 0:v video stream of the first input file.
-map 0:a audio stream of the first input file.
-map 1:a audio stream of the second input file.
-shortest the length of the output is the length of the shortest input
Use case:
add music to your background
you rendered a video, but muted some part of it, so you don't want to render it again(coz it's too long), instead you render only audio track(fast) and wanna merge it with original video.
Assuming
you have your video with you speech (or just audio track, whatever)
your music_file is not loud. Otherwise, you will not hear yourself D:
Steps:
1) Extract audio from the video
ffmpeg -i test.mp4 1.mp3
test.mp4 - your file
2) Merge both audio.mp3 and 1.mp3
ffmpeg -i audio.mp3 -i 1.mp3 -filter_complex amerge -c:a libmp3lame -q:a 4 audiofinal.mp3
audiofinal.mp3 - audio with music
3) Delete audio from original
ffmpeg -i example.mkv -c copy -an example-nosound.mkv
example-nosound.mkv - your video without audio
4) Merge with proper audio
ffmpeg -i audiofinal.mp3 -i example-nosound.wmv -c:v copy -vcodec copy final.wmv
final.wmv - your perfect video.
This is very easy with FFmpeg:
ffmpeg -i vid.mp4 -i audio.mp3 -codec:a libmp3lame -ar 44100 -ab 64k -ac 1 -q:v 1 -pix_fmt yuv420p -map 0:0 -map 1:0
First remove the sound from video if you are not able to merge video and audio by using this command:
ffmpeg -i video.mp4 -an videofinal.mp4

Ffmpeg to duplicate an audio stream and encode this new stream

I have some video files that I need to re-encode due to compatibility issues. They are currently mkv files with h.264 video and ac3-a52 audio. I want to keep the h.264 video, convert the container to m4v and create two audio tracks, one with the original ac3-a52 and one copied from that but in aac stereo.
I assume there has to be some sort of audio stream mapping command but I don't know how to map and re-encode at the same time. What command should I enter into ffmpeg to achieve this?
Also, what is the difference between ac3 and ac3-a52? Will an apple TV still be able to pass through ac3-a52 or does that have to be converted to ac3?
this works for me:
ffmpeg -y -i Source.mkv -map 0:v -c:v copy -map 0:a -c:a copy -map 0:a -strict -2 -c:a aac out.mkv
-y – A global option to overwrite the output file if it already exists.
-map 0:v – Designate the video stream(s) from the first input as a source for the output file.
-c:v copy – Stream copy the video. This just muxes the input to the output. No re-encoding occurs.
-map 0:a – Designate the audio stream(s) from the first input as a source for the output file.
-c:a copy – Stream copy the audio. This just muxes the input to the output. No re-encoding occurs.
-strict -2 -c:a aac – Use the native FFmpeg AAC audio encoder. -strict -2 is required as a way that you acknowledge that the encoder is designated as experimental. It is not a great encoder, but it is not too bad at higher bitrates.
According to wikipedia, there is no difference between AC3 and ATSC A/52: the 1st one is the name of the codec, the 2nd is the name of the standard specifying the AC3 codec. Maybe someone have more knowledge about it?
I'm doing the same as the OP, but with an m4v container. I'm using the MacPorts "nonfree" variant of ffmpeg so that I can use libfaac, which gives better audio quality than the built-in AAC encoder and also had the same issue as #dkam. The command line I ended using is like this:
ffmpeg -i input.m4v -map 0:v -c:v copy -map 0:a -c:a:0 copy -map 0:a -c:a:1 libfaac output.m4v
(The videos are for playback on an iPad, which doesn't seem to be able to handle ac3.)
This command will take a video with 1 audio stream, and downmix to stereo and convert the audio stream and add it as a 2nd audio stream. It will be in AAC 384k.
ffmpeg -i INPUT.mkv -strict -2 -map 0 -c copy -map 0:a:0 -c:a:1 aac -b:a 384k -ac 2 OUTPUT.mkv
Explanation of the command
ffmpeg -i INPUT.mkv The application and input file
-strict -2 Enable downmixing support
-map 0 Tell ffmpeg read all Video, Audio, and Subtitle streams for the following arguments
-c copy Copy everything
-map 0:a:0 Tell ffmpeg to read the first audio stream for the following arguments
-c:a:1 aac Output the audio to a 2nd audio channel (0 = first channel) in aac format. Important! You must change the output channel to a higher number if there are multiple audio streams to prevent overwriting them.
-b:a 384k 384k bitrate (I don't know what's good for aac stereo but this is really high since it's for 5.1 aac)
-ac 2 Downmix to stereo
OUTPUT.mkv Output file
More examples
A video with two audio streams. Creating a third audio stream by encoding the first.
ffmpeg -i INPUT.mkv -strict -2 -map 0 -c copy -map 0:a:0 -c:a:2 aac -b:a 384k -ac 2 OUTPUT.mkv
Again a video with two audio streams, but you want to encode the second one
ffmpeg -i INPUT.mkv -strict -2 -map 0 -c copy -map 0:a:1 -c:a:2 aac -b:a 384k -ac 2 OUTPUT.mkv

How to add a new audio (not mixing) into a video using ffmpeg?

I used a command like:
ffmpeg -i video.avi -i audio.mp3 -vcodec codec -acodec codec output_video.avi -newaudio
in latest version for adding new audio track to video (not mix).
But I updated the ffmpeg to the newest version (ffmpeg version git-2012-06-16-809d71d) and now in this version the parameter -newaudio doesn't work.
Tell me please how I can add new audio to my video (not mix) using ffmpeg.
Replace audio
ffmpeg -i video.mp4 -i audio.wav -map 0:v -map 1:a -c:v copy -shortest output.mp4
The -map option allows you to manually select streams / tracks. See FFmpeg Wiki: Map for more info.
This example uses -c:v copy to stream copy (mux) the video. No re-encoding of the video occurs. Quality is preserved and the process is fast.
If your input audio format is compatible with the output format then change -c:v copy to -c copy to stream copy both the video and audio.
If you want to re-encode video and audio then remove -c:v copy / -c copy.
The -shortest option will make the output the same duration as the shortest input.
Add audio
ffmpeg -i video.mkv -i audio.mp3 -map 0 -map 1:a -c:v copy -shortest output.mkv
The -map option allows you to manually select streams / tracks. See FFmpeg Wiki: Map for more info.
This example uses -c:v copy to stream copy (mux) the video. No re-encoding of the video occurs. Quality is preserved and the process is fast.
If your input audio format is compatible with the output format then change -c:v copy to -c copy to stream copy both the video and audio.
If you want to re-encode video and audio then remove -c:v copy / -c copy.
The -shortest option will make the output the same duration as the shortest input.
Mixing/combining two audio inputs into one
Use video from video.mkv. Mix audio from video.mkv and audio.m4a using the amerge filter:
ffmpeg -i video.mkv -i audio.m4a -filter_complex "[0:a][1:a]amerge=inputs=2[a]" -map 0:v -map "[a]" -c:v copy -ac 2 -shortest output.mkv
See FFmpeg Wiki: Audio Channels for more info.
Generate silent audio
You can use the anullsrc filter to make a silent audio stream. The filter allows you to choose the desired channel layout (mono, stereo, 5.1, etc) and the sample rate.
ffmpeg -i video.mp4 -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=44100 \
-c:v copy -shortest output.mp4
Also see
Combine two audio streams into one
FFmpeg Wiki: Audio Channel Manipulation
FFmpeg mux video and audio from another video
mp3 music to wav
ffmpeg -i music.mp3 music.wav
truncate to fit video
ffmpeg -i music.wav -ss 0 -t 37 musicshort.wav
mix music and video
ffmpeg -i musicshort.wav -i movie.avi final_video.avi
If the input video has multiple audio tracks and you need to add one more then use the following command:
ffmpeg -i input_video_with_audio.avi -i new_audio.ac3 -map 0 -map 1 -codec copy output_video.avi
-map 0 means to copy (include) all streams from the first input file (input_video_with_audio.avi) and -map 1 means to include all streams (in this case one) from the second input file (new_audio.ac3).
None of these solutions quite worked for me. My original audio was being overwritten, or I was getting an error like "failed to map memory" with the more complex 'amerge' example. It seems I needed -filter_complex amix.
ffmpeg -i videowithaudioyouwanttokeep.mp4 -i audiotooverlay.mp3 -vcodec copy -filter_complex amix -map 0:v -map 0:a -map 1:a -shortest -b:a 144k out.mkv
Nothing quite worked for me (I think it was because my input .mp4 video didn't had any audio) so I found this worked for me:
ffmpeg -i input_video.mp4 -i balipraiavid.wav -map 0:v:0 -map 1:a:0 output.mp4
This shows how to merge all audio tracks into one entire directory with ffmpeg:
ffmpeg -i video.mp4 -i audio.mp3 -map 0:v -map 1:a -c:v copy -shortest output.mp4
Here is how I did what the OP wanted.
My setup is I have two stream of media one video (with its own audio channel) & one audio. I am not converting from but I am restreaming live source by integrating it with an additional audio channel without replacing the old audio from the video stream.
Here is the code I used.
ffmpeg -i "Video stream with its own audio" -i "another audio stream" -map 0:v -map 0:a -map 1:a -shortest -f mpegts "multicast udp stream out put"
what the code does is, it maps each video and audio channels after it acquired the streams from the live source. -map 0:v is the video stream, -map 0:a is the audio that is coming from the video source (notice the 0s from the -map) and finally -map 1:a which is the audio stream from the second source.
then it just restreams it using mpegts through a multicast address. You can change this to a file, a unicast stream or any other supported output format.
Here is the code I am using.
ffmpeg -i "rtp://#231.0.0.208:1234" -i "rtp://#231.0.0.206:1234" -map 0:v -map 0:a -map 1:a -shortest -f mpegts "udp://#231.0.0.45:1234"
Hope this helps some one. Thanks!
If you are using an old version of FFMPEG and you cant upgrade you can do the following:
ffmpeg -i PATH/VIDEO_FILE_NAME.mp4 -i PATH/AUDIO_FILE_NAME.mp3 -vcodec copy -shortest DESTINATION_PATH/NEW_VIDEO_FILE_NAME.mp4
Notice that I used -vcodec
Code to add audio to video using ffmpeg.
If audio length is greater than video length it will cut the audio to video length.
If you want full audio in video remove -shortest from the cmd.
String[] cmd = new String[]{"-i", selectedVideoPath,"-i",audiopath,"-map","1:a","-map","0:v","-codec","copy", ,outputFile.getPath()};
private void execFFmpegBinaryShortest(final String[] command) {
final File outputFile = new File(Environment.getExternalStorageDirectory().getAbsolutePath()+"/videoaudiomerger/"+"Vid"+"output"+i1+".mp4");
String[] cmd = new String[]{"-i", selectedVideoPath,"-i",audiopath,"-map","1:a","-map","0:v","-codec","copy","-shortest",outputFile.getPath()};
try {
ffmpeg.execute(cmd, new ExecuteBinaryResponseHandler() {
#Override
public void onFailure(String s) {
System.out.println("on failure----"+s);
}
#Override
public void onSuccess(String s) {
System.out.println("on success-----"+s);
}
#Override
public void onProgress(String s) {
//Log.d(TAG, "Started command : ffmpeg "+command);
System.out.println("Started---"+s);
}
#Override
public void onStart() {
//Log.d(TAG, "Started command : ffmpeg " + command);
System.out.println("Start----");
}
#Override
public void onFinish() {
System.out.println("Finish-----");
}
});
} catch (FFmpegCommandAlreadyRunningException e) {
// do nothing for now
System.out.println("exceptio :::"+e.getMessage());
}
}
The marked answer does not set the audio track's language.
The following is an example that specifies German for the default audio track (the video's only audio channel) and English for the audio track that is added anew:
ffmpeg -i "/dir/video.mkv" -i "/dir2/audio.ac3" -map 0 -map 1:a -c:v copy -shortest -metadata:s:a:0 language=ger -metadata:s:a:0 title="GER" -metadata:s:a:1 language=eng -metadata:s:a:1 title="ENG" "/dir/output.mkv"
(The s:a:0 starts counting from 0, adjust that number as needed. If the audio track language is already specified, you don't need to set it and would only need to set it for the audio track that you add.)

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