- theora: reference encoder/decoder library (previously known as thusnelda, supports all theora features): theora svn, theora official releases.
- theora-ptalarbvorm: development branch of encoder/decoder library with high quality encoder and faster decoder/encoder (see Theora: Ptalarbvorm project update 20100518): theora-ptalarbvorm svn.
- Theorarm: an Ogg Theora/Vorbis decoding library optimised for use on ARM processors: Theorarm web site.
- Leonora: Theora decoder for the C64x+ DSP coprocessor on the OMAP3 SoC manufactured by Texas Instruments. This series of SoCs is used in a variety of mobile devices including the Palm Pre, Motorola Droid, and Nokia’s N series of phones. Leonora web site.
- theora-old: old encoder/decoder library (the decoder does not support all theora features, but it was faster than reference theora 1.0 in many cases); theora version up to 1.0 alpha 7 were using this code trunk: theora-old svn.
- theora-exp: old, no longer developed, experimental encoder/decoder library: theora-exp svn. Its improvements were merged in the 1.1.0 reference library.
- Cortado: a GPL Java decoder for Ogg Theora, Ogg Vorbis and other codecs. Embedding this applet on your website you can give viewers access to streams from either the Flumotion streaming server or play a local file from your server without the need for a locally installed media player supporting the correct formats on the visitors computer. See also OggHandler.
- ffmpeg: old versions didn't support all theora features (showing corrupted frames) and were also a lot slower than libtheora. Newer version improved somewhat (see also this comment from Monty).
See also Theora Hardware for hardware implementations.
Decoder front ends
- libtheoraplayer: Simple to use and powerful API for playing Theora videos.
- Etheora: a simplified API to theora reference encoder/decoder.
- Theora Hardware: List of hardware-players supporting Ogg Theora
- TheoraSoftwarePlayers: List of media players that can play Ogg Theora
- TheoraSoftwareEncoders: List of software that can encode to Ogg Theora
- TheoraDecoders: List of decoder implementations
- TheoraEncoders: List of encoder implementations
- List of Theora videos: Get some files to see what the codec's like
- Games that use Theora: List of known games that use Theora
- TheoraTestsuite: Different samples to test player compliance