feat: derive serde traits on ffmpeg types

refactor: address requested changes

src/util/channel_layout.rs

@@ -3,6 +3,8 @@ use libc::c_ulonglong;
 use crate::ffi::*;
 
 bitflags! {
+		#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+		#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 		pub struct ChannelLayout: c_ulonglong {
 				const FRONT_LEFT            = AV_CH_FRONT_LEFT;
 				const FRONT_RIGHT           = AV_CH_FRONT_RIGHT;

src/util/chroma/location.rs

@@ -1,6 +1,8 @@
 use crate::ffi::{AVChromaLocation::*, *};
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 pub enum Location {
 	Unspecified,
 	Left,

src/util/color/primaries.rs

@@ -1,6 +1,8 @@
 use crate::ffi::{AVColorPrimaries::*, *};
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 pub enum Primaries {
 	Reserved0,
 	BT709,

src/util/color/range.rs

@@ -1,6 +1,8 @@
 use crate::ffi::{AVColorRange::*, *};
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 pub enum Range {
 	Unspecified,
 	MPEG,

src/util/color/space.rs

@@ -3,6 +3,8 @@ use std::{ffi::CStr, str::from_utf8_unchecked};
 use crate::ffi::{AVColorSpace::*, *};
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 pub enum Space {
 	RGB,
 	BT709,

src/util/color/transfer_characteristic.rs

@@ -1,6 +1,8 @@
 use crate::ffi::{AVColorTransferCharacteristic::*, *};
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 pub enum TransferCharacteristic {
 	Reserved0,
 	BT709,

src/util/format/pixel.rs

@@ -8,6 +8,8 @@ use thiserror::Error;
 use crate::ffi::{AVPixelFormat::*, *};
 
 #[derive(Eq, PartialEq, Copy, Clone, Debug)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 pub enum Pixel {
 	None,
 

src/util/format/sample.rs

@@ -11,6 +11,8 @@ use libc::c_int;
 use crate::ffi::{AVSampleFormat::*, *};
 
 #[derive(Eq, PartialEq, Copy, Clone, Debug)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 pub enum Sample {
 	None,
 
@@ -22,6 +24,8 @@ pub enum Sample {
 	F64(Type),
 }
 
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 #[derive(Eq, PartialEq, Copy, Clone, Debug)]
 pub enum Type {
 	Packed,

src/util/rational.rs

@@ -9,6 +9,8 @@ use libc::c_int;
 use crate::ffi::*;
 
 #[derive(Copy, Clone)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "kebab-case"))]
 pub struct Rational(pub i32, pub i32);
 
 impl Rational {