Building omxplayer on a Raspberry Pi

The past couple days, I set aside my PIC work and concentrated on setting up a Raspberry Pi ("RPi"). I've got a couple of these, and will use them as video streamers for televisions in my house.

There is quite a bit of documentation for getting an RPi set up, so I won't repeat that here. My current focus is on getting video streaming working. An obvious candidate is RaspBMC, but I was looking for something very bare-bones to simply put a video onto the HDMI output. I ran across PyPlex which seemed right up my alley: Python and effectively an interface-less control of the video.

Yah. Well. Then I look at the setup/build requirements. twisted-web? pexpect? Seriously? Somebody has made this much more complicated than it should be. Whatever happened to just using BaseHTTPServer and the subprocess module?

Digging in, I find it is using omxplayer underneath. No wonder they're using pexpect -- there is a tty/keyboard interface to omxplayer. (of course, pty might be simpler than pexpect, but whatever) So this PyPlex thing starts up a web service and then controls omxplayer via a tty connection. I'm not seeing reliability and responsiveness here. And a lot of code, to boot.

Tearing off another layer of the onion, I start looking at omxplayer. Sigh. Requirements hell yet again. GCC 4.7. Boost. ffmpeg. Oh, and it is generally set up for cross-compilation rather than building on the RPi. This isn't a bad concept in general, as the RPi is no speed demon. But the build only takes a long time because they chose ffmpeg, whereas the Raspbian distribution uses libav. (these two libraries are reasonably similar, as libav forked from ffmpeg rather nastily a couple years ago)

So I'm looking at this giant pile of C++ code with a bunch of crazy requirements, which would take hours to build on my RPi. This is the wonderful state of video on the RPi. Sigh.

Well... I found a post by Keith Wright where he talks about building (a tweaked fork) of omxplayer on Raspbian. Much better, but the instructions still have crazy oddities about reconfiguring RAM, sudo to build in strange filesystem locations, and hey! fun! building ffmpeg from scratch again. Sigh. A guy just can't get any love around here.

Being the good geek that I am... this just wasn't something that I want to put up with. I want to build this sucker on my RPi, using standard tooling and libraries that come on Raspbian.

First up, I started from huceke/omxplayer rather than Keith's because it is much newer. But I did grab the Makefile.include from Keith, as it was sane for building on the RPi. Adjusted some of the paths to point to the installed items. Then, I had to install the following packages on the RPi: libpcre3-dev, libavcodec-dev, libavdevice-dev, libavfilter-dev, libavformat-dev, libboost-dev. As I started working through getting omxplayer built, I ran into a bug in a system header.

In /opt/vc/include/interface/vmcs_host/vcgencmd.h, line 33 needs to be changed to:

#include "interface/vmcs_host/linux/vchost_config.h"

I've filed a pull request to github:raspberrypi/firmware to fix this. Not sure if that is the Right place (that code may come from upstream?), but hopefully somebody will see it.

Next up, I had to hack away, tweak, and otherwise put a bit of pain on the omxplayer sources. Some hacks were easy, but others likely broke stuff (I'm not sure if subtitles work any more). Hard to tell. A/V code is not easy, and not something that I'm familiar with.

You can find all of my changes in my omxplayer fork. Clone that to your RPi, install the necessary packages, and hit "make". No system reconfiguration. No sudo. No hours of ffmpeg building. No GCC 4.7 requirement.

Clone. Make.

Go have fun, and watch some movies!

(my next step is to tear off the user interface bits, and shift to a simpler, pure-C library which I can wrap/control from Python)