Add serialize support for enums

src/codec/encoder/comparison.rs

@@ -1,7 +1,10 @@
 use ffi::*;
 use libc::c_int;
+#[cfg(feature = "serialize")]
+use serde::{Deserialize, Serialize};
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug)]
+#[cfg_attr(feature = "serialize", derive(Serialize, Deserialize))]
 pub enum Comparison {
     SAD,
     SSE,

src/codec/encoder/decision.rs

@@ -1,7 +1,10 @@
 use ffi::*;
 use libc::c_int;
+#[cfg(feature = "serialize")]
+use serde::{Deserialize, Serialize};
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug)]
+#[cfg_attr(feature = "serialize", derive(Serialize, Deserialize))]
 pub enum Decision {
     Simple,
     Bits,

src/codec/encoder/motion_estimation.rs

@@ -1,6 +1,9 @@
 use libc::c_int;
+#[cfg(feature = "serialize")]
+use serde::{Deserialize, Serialize};
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug)]
+#[cfg_attr(feature = "serialize", derive(Serialize, Deserialize))]
 pub enum MotionEstimation {
     Zero,
     Full,

src/codec/encoder/prediction.rs

@@ -1,7 +1,10 @@
 use ffi::*;
 use libc::c_int;
+#[cfg(feature = "serialize")]
+use serde::{Deserialize, Serialize};
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug)]
+#[cfg_attr(feature = "serialize", derive(Serialize, Deserialize))]
 pub enum Prediction {
     Left,
     Plane,