diff --git a/src/demux/flv.rs b/src/demux/flv.rs
index b023383..97cb56e 100644
--- a/src/demux/flv.rs
+++ b/src/demux/flv.rs
@@ -74,7 +74,7 @@ impl input::FileReader for FLVReader {
         self.skip_init_header()?;
         return self.read_metadata()
     }
-    fn read_nalu(&mut self) -> Result<util::NALUPacket, Box<dyn Error>> {
+    fn read_nalu(&mut self, metadata: &util::Metadata) -> Result<util::NALUPacket, Box<dyn Error>> {
         todo!();
     }
 }
diff --git a/src/demux/input.rs b/src/demux/input.rs
index 26d8f06..a4dece6 100644
--- a/src/demux/input.rs
+++ b/src/demux/input.rs
@@ -1,13 +1,36 @@
 use std::error::Error;
 use std::io;
 use std::io::Read;
+use std::sync::mpsc;
 
 use crate::util;
 use crate::demux::flv;
 
 pub trait FileReader {
     fn init(&mut self) -> Result<util::Metadata, Box<dyn Error>>;
-    fn read_nalu(&mut self) -> Result<util::NALUPacket, Box<dyn Error>>;
+    fn read_nalu(&mut self, metadata: &util::Metadata) -> Result<util::NALUPacket, Box<dyn Error>>;
+    fn data_loop(&mut self, v_in: mpsc::Sender<util::NALUPacket>, a_in: mpsc::Sender<util::NALUPacket>, metadata: &util::Metadata, err_in: mpsc::Sender<Box<dyn Error>>) {
+        loop {
+            let nalu = match self.read_nalu(metadata) {
+                Ok(x) => x,
+                Err(err) => {util::thread_freeze(err_in, err); return}
+            };
+            match nalu.packet_type {
+                util::NALUPacketType::Audio => {
+                    match a_in.send(nalu) {
+                        Ok(_) => (),
+                        Err(err) => {util::thread_freeze(err_in, Box::new(err)); return}
+                    }
+                }
+                util::NALUPacketType::Video => {
+                    match v_in.send(nalu) {
+                        Ok(_) => (),
+                        Err(err) => {util::thread_freeze(err_in, Box::new(err)); return}
+                    }
+                }
+            }
+        }
+    }
 }
 
 pub fn new_reader() -> Result<impl FileReader, Box<dyn Error>> {
diff --git a/src/util/mod.rs b/src/util/mod.rs
index c5eba22..f6a3ce2 100644
--- a/src/util/mod.rs
+++ b/src/util/mod.rs
@@ -1,5 +1,7 @@
 use std::error::Error;
 use std::fmt;
+use std::thread;
+use std::sync::mpsc;
 
 // Data structs/enums
 
@@ -108,3 +110,10 @@ impl fmt::Display for DemuxerError {
         fmt::Debug::fmt(self, f)
     }
 }
+
+// funcs
+
+pub fn thread_freeze(err_sender: mpsc::Sender<Box<dyn Error>>, err: Box<dyn Error>) {
+    err_sender.send(err).unwrap();
+    thread::park();
+}