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So you downloaded an HD .mkv video file. So you wanna watch your nice video on your Xbox 360 but you don’t want to use Windows? Well look no further, you can do this quickly and easily. No need to re-encode the video and wait for an hour or longer, extract and remux the streams to an mp4 and stream it across your home network with a UPnP program like fuppes or ushare. I have created a script based on the DIY steps found at LinuxLove.info. I have Ubuntu, so this guide will describe how to install the needed programs using Ubuntu’s apt-get package manager. So sit back, sip your coffee and learn.

Well, a lot of people use MP4Box for this sort of thing, but I was not able to get it to work, install, or compile at all on my system, instead I used mp4creator. So first thing is first, we need to install the necessary programs.

Setting Up

The necessary programs are mkvmerge, mkvextract (package mkvtoolnix), bbe, mplayer, normalize-audio, neroAacEnc, and mp4creator.
sudo apt-get update && sudo apt-get install mkvtoolnix bbe mplayer normalize-audio mpeg4ip-server
The only program we can’t get from the ubuntu repositories is neroAacEnc (The nero encoder for AAC). This can be gotten from here. Then do the following.
unzip NeroDigitalAudio.zip
cd linux
sudo mv neroAacEnc /usr/bin
sudo chmod +x /usr/bin/neroAacEnc
Afterwards you can remove the zip and the files you extracted from it. Now we’re all set up.

Explaining the Script

I’m going to go through the commands that the script uses so you can see what is going on. If you don’t care how it works, and just want to use it, just skip to the bottom and download the script.
VID=`mkvmerge -i "$MKV" | grep "Track ID .: video" | awk '{ print sprintf("%d",$3) }'`
FPS=`mplayer -identify "$MKV" -vc null -ao null -vo null -frames 0 2>/dev/null | grep ^ID_VIDEO_FPS | sed -e 's/^.*=//'`
BASE=`echo $MKV | sed 's/\.mkv//'`
This fills the VID variable with the Track ID of the video track from the mkv file, and FPS will have (can you guess?) FPS of the video. BASE will be the filename without the ‘.mkv’ at the end.
mkvextract tracks "$MKV" "$VID:$BASE.h264"
This extracts the video track from the file. We aren’t converting or anything, just taking the existing video from the file and taking it out of its container.
bbe -e "r 7 \41" --output="$BASE.tmp.h264" "$BASE.h264"
This changes the profile level to 4.1, this works on 90% of mkv files, but a few may still have some artifacts. Now we extract our audio from the video.
mplayer "$MKV" -novideo -vc null -vo null -ao pcm:fast:file="$BASE.wav" -channels 2
Then (this part is optional, just remove it from the script if you don’t want it, or time is of the essence) we normalize the audio levels. Personally I think this is great so if you have a video where the audio level is not consistent, this will fix it.
normalize-audio "$BASE.wav"
Then we just need to encode the audio from wav to m4a, unfortunately MP4Box was able to use m4a’s instead since we’re using mp4creator there’s the extra step of converting to the aac.
neroAacEnc -lc -ignorelength -q 0.50 -if "$BASE.wav" -of "$BASE.m4a"
mp4creator --extract=1 "$BASE.m4a" "$BASE.aac"
The -q value is for the quality. Smaller will produce a smaller file, higher will produce a larger but better looking file. Personally, I find that 0.5 is excellent quality and the file size is roughly the same as the original mkv if not a little smaller.
mp4creator --create="$BASE.tmp.h264" -rate=$FPS "$BASE.mp4"
mp4creator --create="$BASE.aac" -rate=$FPS "$BASE.mp4"
And those two commans remux the video and audio together into our new mp4 file. Shiny.

I admit, majority of these steps were just taken directly from the above LinuxLove link. It was quick and easy to put together this script with some tweaks (such as using mp4creator.) The script isn’t very robust, its just down and dirty simple. There are probably more robust scripts out there. Or if someone wants, I can add some extra functionality into my script. Enjoy my script!

Just one thing, for some reason the creation of the mp4 file produces a message “Error decoding sei message”. I don’t know if its the videos, or if its a usual thing all I know is that the videos come out perfectly fine with no problems. So its something that can be ignored, if someone knows the reason for/way to fix this error, I’d love to find out. =)

In another post I’ll go over the setting up of the fuppes program for streaming your brand new HD mp4 videos to your xbox 360.

w00t w00t.