[theora-dev] Inverse DCT in coding stage

Timothy B. Terriberry tterribe at xiph.org
Fri Apr 8 06:48:15 PDT 2011

> Why in the procedure oc_enc_block_transform_quantize() is used function oc_idct8x8()?
> After all, Inverse DCT only need to decoding stage, rather than coding?

Future frames are predicted from past frames. It's necessary for the 
encoder to know what the decoder will have decoded so that it knows what 
the decoder will be using for its prediction.

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