diff --git a/src/demux/flv.rs b/src/demux/flv.rs
index ffb8dae..bf777a4 100644
--- a/src/demux/flv.rs
+++ b/src/demux/flv.rs
@@ -96,7 +96,7 @@ fn process_metadata(mut data: Vec<u8>) -> Result<util::Metadata, Box<dyn Error>>
     for _ in 0..arr_len {
         let key = String::fetch_amf_val(&mut data);
         let amf_marker = u8::fetch_amf_val(&mut data);
-        if !handle_relevant_keys(key, &mut data, &amf_marker, &mut metadata) {
+        if !handle_relevant_keys(key, &mut data, &amf_marker, &mut metadata)? {
             match amf_marker {
                 0 => {let _ = f64::fetch_amf_val(&mut data);},
                 1 => {let _ = bool::fetch_amf_val(&mut data);},
@@ -108,8 +108,26 @@ fn process_metadata(mut data: Vec<u8>) -> Result<util::Metadata, Box<dyn Error>>
     return Ok(metadata);
 }
 
-fn handle_relevant_keys(key: String, data: &mut Vec<u8>, marker: &u8, metadata: &mut util::Metadata) -> bool {
-    todo!();
+fn handle_relevant_keys(key: String, data: &mut Vec<u8>, marker: &u8, metadata: &mut util::Metadata) -> Result<bool, Box<dyn Error>> {
+    match key.as_str() {
+        "width" => {metadata.video.width = f64::fetch_amf_val(data) as u32; Ok(true)},
+        "height" => {metadata.video.height = f64::fetch_amf_val(data) as u32; Ok(true)},
+        "framerate" => {metadata.video.framerate = f64::fetch_amf_val(data) as f32; Ok(true)},
+        "videocodecid" => {
+            match f64::fetch_amf_val(data) as u8 {
+                7 => {metadata.video.codec = Some(util::VideoCodec::H264); Ok(true)},
+                _ => {Err(Box::new(util::DemuxerError::CodecNotImplemented))}
+            }
+        },
+        "stereo" => {metadata.audio.channels = if bool::fetch_amf_val(data) {2} else {1}; Ok(true)},
+        "audiosamplerate" => {metadata.audio.samplerate = f64::fetch_amf_val(data) as u32; Ok(true)},
+        "audiocodecid" => {
+            match f64::fetch_amf_val(data) as u8 {
+                10 => {metadata.audio.codec = Some(util::AudioCodec::AAC); Ok(true)},
+                _ => {Err(Box::new(util::DemuxerError::CodecNotImplemented))}
+            }
+        }
+    }
 }
 
 trait FetchAMFVal {
diff --git a/src/util/mod.rs b/src/util/mod.rs
index 6801cf9..73caebc 100644
--- a/src/util/mod.rs
+++ b/src/util/mod.rs
@@ -66,6 +66,7 @@ pub enum DemuxerError {
     FLVPacketNotMetadata,
     FLVMetadataSyncFail,
     FLVMetadataAMFMarkerError,
+    CodecNotImplemented,
 }
 
 impl Error for DemuxerError {}
@@ -79,6 +80,7 @@ impl fmt::Debug for DemuxerError {
             DemuxerError::FLVPacketNotMetadata => write!(f, "Did not find expected metadata tag"),
             DemuxerError::FLVMetadataSyncFail => write!(f, "ECMA array not where expected"),
             DemuxerError::FLVMetadataAMFMarkerError => write!(f, "Marker value not recognized/implemented"),
+            DemuxerError::CodecNotImplemented => write!(f, "Input file has unrecognized codec"),
             _ => write!(f, "Error not described yet")
         }
     }