Simple Video Player for Raspberry Pi




Simple Video Player on Raspberry Pi

Did you know that you can easily code an audio video player with the latest version 0.8.4 of GLSL Hacker ? This is possible thanks to the FFmpeg plugin that can now read audio and video frames and synchronize them. The FFmpeg plugin is available with all versions of GLSL Hacker: Windows, Linux, OS X and, of course, Raspberry Pi.

I prepared an archive file for Raspberry Pi with a ready-to-use video player named vplay. vplay is simply GLSL Hacker that has been renamed in vplay. The full source code in Lua is included in the download (in the audio_video/ folder):



In a word, vplay is a video player based on GLSL Hacker that uses FFmpeg to decode audio-video files, OpenMAX to play the decoded audio buffer and OpenGL ES to display the decoded video frames.

Playing a video with vplay is simple. Open a terminal in vplay folder and pass the absolute path to the video file:

$ vplay /video=\"video_file_absolute_path\"

A concrete example:

$ vplay /video=\"/home/pi/mykoolvideo.mp4\"

You can also force the resolution and fullscreen mode like this:

$ vplay /width=1920 /height=1080 /fullscreen /video=\"/home/pi/mykoolvideo.mp4\"

/width, /height and /fullscreen are command line parameters of GLSL Hacker and are not specific to VPlay demo.

By default, the video is played on a quad with an orthographic camera (a 2D camera). But vplay can be easily tweaked to play the video on another kind of support like a 3D box. After all, in a FRAME script, a video is just a simple 2D texture that can be mapped (like any other texture) on any 3D object. I added a command line parameter /usebox (you can add other params by parsing the command line in Lua, look for the gh_utils.get_command_line() function in the source code of the demo, line 167) to play the video using a 3D cube and a perspective camera:

$ vplay /video=\"/home/pi/mykoolvideo.mp4\" /usebox

And the result:


Simple Video Player on Raspberry PiThe video played on a 3D cube

And since the video is a simple 2D texture, you can play with the uv tiling factor in the pixel shader (line 31 and 388 of the xml file):


Simple Video Player on Raspberry PiThe video played on a quad with a texture tiling factor of 2.0

If you are interested about how vplay works, here are some code snippets that show how to use the audio-video functions of the FFmpeg plugin (Lua or Python) in GLSL Hacker:

INIT script:

-- Opening of the video file.
av1 = gh_av.decoder_open(av_filename, loop_mode)

-- video resolution. 
video_width, video_height = gh_av.video_get_resolution(av1)

-- Creation of a 2D texture with correct resolution (width x height). 
video_tex = gh_av.video_init_texture(av1, PF_U8_RGB)

-- Starting of the audio-video processing thread.
gh_av.start_audio_video_processing(av1, update_video, update_audio)

FRAME script:

-- Binding of the video texture and updating from the current video frame.
gh_texture.bind(video_tex, 0)
gh_av.video_update_texture(av1, video_tex)

-- Now the texture can be mapped on any mesh.

TERMINATE script:

-- Stopping of the audio-video processing thread.
gh_av.stop_audio_video_processing(av1)

-- Closing of the video file.
gh_av.decoder_close(av1)

The full source code is in the archive, so do not hesitate to hack it!