add support for ugoira

add progress bar

src/ext/json.rs

@@ -0,0 +1,35 @@
+use json::JsonValue;
+
+pub trait ToJson {
+    fn to_json(&self) -> Option<JsonValue>;
+}
+
+impl ToJson for &str {
+    fn to_json(&self) -> Option<JsonValue> {
+        Some(JsonValue::String(String::from(*self)))
+    }
+}
+
+impl ToJson for &String {
+    fn to_json(&self) -> Option<JsonValue> {
+        Some(JsonValue::String((*self).to_string()))
+    }
+}
+
+impl ToJson for String {
+    fn to_json(&self) -> Option<JsonValue> {
+        Some(JsonValue::String(self.to_string()))
+    }
+}
+
+impl ToJson for JsonValue {
+    fn to_json(&self) -> Option<JsonValue> {
+        Some(self.clone())
+    }
+}
+
+impl ToJson for &JsonValue {
+    fn to_json(&self) -> Option<JsonValue> {
+        Some((*self).clone())
+    }
+}

src/ext/mod.rs

@@ -1,5 +1,6 @@
 pub mod cstr;
 #[cfg(feature = "flagset")]
 pub mod flagset;
-#[cfg(any(feature = "exif", feature = "avdict"))]
+pub mod json;
+#[cfg(any(feature = "exif", feature = "avdict", feature = "ugoira"))]
 pub mod rawhandle;

src/ext/rawhandle.rs

@@ -2,4 +2,9 @@
 pub trait ToRawHandle<T> {
     /// Return raw pointer of the handle
     unsafe fn to_raw_handle(&self) -> *mut T;
+
+    /// Return the const raw pointer of the handle
+    unsafe fn to_const_handle(&self) -> *const T {
+        self.to_raw_handle() as *const T
+    }
 }