FFmpeg Mplayer VLC - News & Howtos

[Merrattic]

This thread has been started to provide those in the know, and those wanting to know, a place to discuss developments, changes, tips, tricks, one liners, scripts in ffmpeg, mplayer, vlc and similar associated programs. Submissions and questions alike. If posting something different / new in this thread, on replying go advanced and edit the title accordingly, also use the tag facility to assist with searches

I'll kick things off with a few links:

FFMpeg
http://ffmpeg.org & http://ffmpeg.org/trac/ffmpeg/wiki

Mplayer
http://www.mplayerhq.hu

VLC
http://www.videolan.org/vlc/index.html

[andrew.46]

Thanks for starting this thread Merratic! I would like to kick off with a great link:

Welcome to the FFmpeg Bug Tracker and Wiki
https://ffmpeg.org/trac/ffmpeg/wiki

Some great info specific to Ubuntu and FFmpeg, some of it based on information formerly hosted on these Forums. Of great interest currently is the new ability of FFmpeg to burn subtitles into video streams:

How to burn subtitles into the video
https://ffmpeg.org/trac/ffmpeg/wiki/...%20the%20video

I have given this filter a run and for my simple needs it works very, very well.

[nothingspecial]

This is great. Discussion of new developments is always welcome.

If anyone asks a support question within this thread I hope they will be encouraged to start a thread of their own in which we can link back to the information in this thread or the other fantastic documentation available.

[Merrattic]

@ Andrew.46 re subtitles

How to setup the subtitle file in the first place? Is there an associated program for this? I would use this for example in screen recordings to add text to a tutorial.....

EDIT: found myself, use either subtitleeditor or gaupol both in the main repos

[ron999]

... one liners

OK
Here is a one-liner.
A way howto use neroAacEnc with FFmpeg.

ffmpeg -i "input" -c:v libx264 -crf 23 -preset medium -an output.mp4 -f wav - | neroAacEnc -if - -q 0.5 -ignorelength -of soundtrack.aac && MP4Box output.mp4 -add soundtrack.aac

And the deluxe version:-

tempname=$(date +"%s"); \
ffmpeg -i "input" \
-c:v libx264 -crf 23 -preset medium -an output.mp4 \
-f wav - | neroAacEnc -if - -q 0.5 -ignorelength -of $tempname.aac && \
MP4Box output.mp4 -add $tempname.aac && \
rm -f $tempname.aac

Also for mkv:-

tempname=$(date +"%s"); \
ffmpeg -i "input" \
-c:v libx264 -crf 23 -preset medium -an $tempname.mkv \
-f wav - | neroAacEnc -if - -q 0.5 -ignorelength -of $tempname.aac && \
mkvmerge -o output.mkv $tempname.mkv $tempname.aac && \
rm -f $tempname.mkv $tempname.aac

[nothingspecial]

@ Andrew.46 re subtitles

How to setup the subtitle file in the first place? Is there an associated program for this? I would use this for example in screen recordings to add text to a tutorial.....

EDIT: found myself, use either subtitleeditor or gaupol both in the main repos

Please do not use this thread to ask specific questions.

If someone is searching the forums for an answer about subtitle files, how are they expected to find it in a thread titled "FFmpeg Mplayer VLC - News & Howtos" ?

[nothingspecial]

OK
Here is a one-liner.
A way howto use neroAacEnc with FFmpeg.

ffmpeg -i "input" -c:v libx264 -crf 23 -preset medium -an output.mp4 -f wav - | neroAacEnc -if - -q 0.5 -ignorelength -of soundtrack.aac && MP4Box output.mp4 -add soundtrack.aac

And the deluxe version:-

tempname=$(date +"%s"); \
ffmpeg -i "input" \
-c:v libx264 -crf 23 -preset medium -an output.mp4 \
-f wav - | neroAacEnc -if - -q 0.5 -ignorelength -of $tempname.aac && \
MP4Box output.mp4 -add $tempname.aac && \
rm -f $tempname.aac

Also for mkv:-

tempname=$(date +"%s"); \
ffmpeg -i "input" \
-c:v libx264 -crf 23 -preset medium -an $tempname.mkv \
-f wav - | neroAacEnc -if - -q 0.5 -ignorelength -of $tempname.aac && \
mkvmerge -o output.mkv $tempname.mkv $tempname.aac && \
rm -f $tempname.mkv $tempname.aac

awesome, thanks.

[evilsoup]

HOW TO: concatenate MP4 files with h264 video & AAC audio without re-encoding.

Note that this will only work on files with the same parameters - same frame rate, etc. This should be adaptable to other MPEG files (MPEG4/divx, MPEG2, MP3 or MP2 audio), though you'd have to change the bitstream filters.

First, create some named pipes:

mkfifo temp1 temp2

Then, you're going to need to transfer the videos to MPEG Transport Streams, which makes it possible to concatenate, and then do the actual concatenation using ffmpeg's concat protocol.

ffmpeg -i input1.mp4 -c copy -bsf h264_mp4toannexb -f mpegts -y temp1 2> /dev/null & \
ffmpeg -i input2.mp4 -c copy -bsf h264_mp4toannexb -f mpegts -y temp2 2> /dev/null & \
ffmpeg -f mpegts -i "concat:temp1|temp2" -c copy -absf aac_adtstoacs output.mp4

As far as I know, you can use this to concatenate an arbitrary number of MP4 files, though I've not had a reason to try it on more than three files myself. I might whip up a bash script to reduce the typing needed.

EDIT: also, it should be noted that you only need to use a transport stream because of the video. If you only have MP3 or AAC audio (even in an MP4 container) you should be able to feed them to the concat protocol as-is, withoutv mucking around with pipes.

[ron999]

HOW TO: concatenate MP4 files with h264 video & AAC audio without re-encoding.

Hi
For this type of file, doesn't MP4Box do the same thing?

MP4Box input1.mp4 -cat input2.mp4 -out output.mp4

[evilsoup]

Yes. But I've found the ffmpeg way to work on some files that MP4Box doesn't.

And besides, this is the ffmpeg, Mplayer & VLC thread