If I don't remenber incorrectly the rANS does some things in a reverse way and othes things that complicated the cost of implimentation in hardware, in other works of implementing in silicon the 16 multipliers in Daala range coder is cheapier than implementing the memory need to implement the rANS. Also it apears that rANS can increase the latency specially at low rates due to the buffers. Most of this problems are being tackled in a new generation of ANS coders, but they are not going to be ready for a possible implementation in AV1.
Also remenber: Faster/cheapier in software is not the same as faster/cheapier in hardware.
|