TODO: Add TODO list

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+Background
+==========
+
+- Priority scale: High, Medium and Low
+
+- Complexity scale: C1, C2, C4 and C8.  The complexity scale is exponential,
+  with complexity 1 being the lowest complexity.  Complexity is a function
+  of both task 'complexity' and task 'scope'.
+
+  The general rule of thumb is that a complexity 1 task should take 1-2 weeks
+  for a person very familiar with oFono codebase.  Higher complexity tasks
+  require more time and have higher uncertainty.
+
+  Higher complexity tasks should be refined into several lower complexity tasks
+  once the task is better understood.
+
+NEON instruction set
+====================
+
+- The neon optimization code is split in two parts. Sample reordering and blocks
+encoding. There is a neon optimization for encoding SBC. But mSBC is not
+supported by this optimizer because the reordering has been specifically for
+mSBC.
+
+  Priority: Low
+  Complexity: C2
+
+SSE instruction set
+===================
+
+- The decoder is optimized to take advantage of advanced processor instruction
+sets. Currently implemented are MMX, arm neon, arm v6 and iwmmxt. SSE3 is
+is available since almost 10 years now, on a large range of Intel processors.
+It should be interesting to implement it and to compare with MMX implementation
+on Intel processors.
+
+  Priority: Medium
+  Complexity: C4
+
+Decoder improvements
+====================
+
+- Currently, only the decoder is optimized to take advantage of advanced
+processor instruction sets. In use cases like HFP 1.6, optimizing the encoder
+will bring a significant latency, power and performance advantage. For exemple,
+the MMX encoder is 3 to 6 time faster than the SIMD encoder.
+
+  Priority: High
+  Complexity: C8