Multimedia facilities

Audio and Video capabilities

Kamaelia.Audio contains components implementing audio input and output as well as support for some codecs such as MP3. These are provided by using the cross-platform pymedia library (make sure you have installed it!). Some bespoke components for audio filtering and mixing are also held here.

Kamaelia.Codec contains components for encoding and decoding Dirac video, and Speex and Ogg Vorbis audio, as well as support for parsing raw data into video frame data structures. There is also a libAO based audio player, which obviously requires libAO and the pyao python bindings.

Formats used to pass audio and video between components

Audio components for the most part pass around raw audio data as raw pcm data in python strings.

Uncompressed raw video is passed around as whole frames - using a dictionary structure containing the raw data and useful metadata such as the width, height, pixel format and frame rate.

Where to look:

See Kamaelia.Audio for:

• Audio Input / Capture (pymedia)
• Audio Output / Playback (pymedia)
• MP3 audio Encoding (pymedia)
• MP3 audio Decoding (pymedia)
• Audio resampling
• Audio filtering
• Audio mixing

See Kamaelia.Codec for:

• Ogg Speex audio encoding
• Ogg Speex audio decoding
• Ogg Vorbis audio decoding
• Audio output / Playback (libAO)
• Dirac video encoding
• Dirac video decoding
• Raw data framing for video

-- Matt, April 2007