Add generic filter function

Author: pedromsilvapt

src/Filters/Base/GenericFilter.ts

@@ -0,0 +1,26 @@
+import { NativeFilter, FilterNamedArguments } from './Filter';
+import { Stream } from '../../Stream';
+
+export class GenericFilter extends NativeFilter {
+    constructor ( inputs : Stream[] | NativeFilter, name : string, parameters : FilterNamedArguments, outputs : number = 1 ) {
+        super( parameters );
+        
+        this.name = name;
+
+        this.outputsCount = outputs;
+
+        this.from( inputs as any );
+    }
+}
+
+export function filter ( inputs : Stream[] | NativeFilter, name : string, parameters : FilterNamedArguments ) : Stream;
+export function filter ( inputs : Stream[] | NativeFilter, name : string, parameters : FilterNamedArguments, outputs : number ) : Stream[];
+export function filter ( inputs : Stream[] | NativeFilter, name : string, parameters : FilterNamedArguments, outputs ?: number ) : Stream | Stream[] {
+    const filterInstance = new GenericFilter( inputs, name, parameters, outputs );
+
+    if ( outputs == void 0 ) {
+        return filterInstance.outputs[ 0 ];
+    }
+
+    return filterInstance.outputs;
+}

src/main.ts

@@ -11,6 +11,7 @@ export { Stream, DynamicStream, DyanamicInputStream, OutputStream, SelectionStre
 
 export { IFilter } from './Filters/Base/IFilter';
 export { NativeFilter, FilterArgument, FilterNamedArguments } from './Filters/Base/Filter';
+export { GenericFilter, filter } from './Filters/Base/GenericFilter';
 
 export { crossfade } from './Filters/CrossfadeFilter';
 export { concat, separator } from './Filters/ConcatFilter';