diff --git a/codec/h264/lex.go b/codec/h264/lex.go
index 2ed93fd3..9600b104 100644
--- a/codec/h264/lex.go
+++ b/codec/h264/lex.go
@@ -3,7 +3,7 @@ NAME
   lex.go
 
 DESCRIPTION
-  See Readme.md
+  lex.go provides a lexer to lex h264 bytestream into access units.
 
 AUTHOR
   Dan Kortschak <dan@ausocean.org>
@@ -24,6 +24,7 @@ LICENSE
   You should have received a copy of the GNU General Public License
   along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
 */
+
 package h264
 
 import (
diff --git a/codec/h264/lex_test.go b/codec/h264/lex_test.go
index 50b735bd..13efec14 100644
--- a/codec/h264/lex_test.go
+++ b/codec/h264/lex_test.go
@@ -3,7 +3,7 @@ NAME
   lex_test.go
 
 DESCRIPTION
-  See Readme.md
+  lex_test.go provides tests for the lexer in lex.go.
 
 AUTHOR
   Dan Kortschak <dan@ausocean.org>
diff --git a/codec/mjpeg/lex.go b/codec/mjpeg/lex.go
index 5595f588..06e95a05 100644
--- a/codec/mjpeg/lex.go
+++ b/codec/mjpeg/lex.go
@@ -3,7 +3,7 @@ NAME
   lex.go
 
 DESCRIPTION
-  See Readme.md
+  lex.go provides a lexer to extract separate JPEG images from a MJPEG stream.
 
 AUTHOR
   Dan Kortschak <dan@ausocean.org>
@@ -25,7 +25,6 @@ LICENSE
   along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
 */
 
-// Package lex provides lexers for video encodings.
 package mjpeg
 
 import (
@@ -42,7 +41,7 @@ func init() {
 	close(noDelay)
 }
 
-// MJPEG parses MJPEG frames read from src into separate writes to dst with
+// Lex parses MJPEG frames read from src into separate writes to dst with
 // successive writes being performed not earlier than the specified delay.
 func Lex(dst io.Writer, src io.Reader, delay time.Duration) error {
 	var tick <-chan time.Time
diff --git a/codec/mjpeg/lex_test.go b/codec/mjpeg/lex_test.go
index 0888ce3d..e92633f3 100644
--- a/codec/mjpeg/lex_test.go
+++ b/codec/mjpeg/lex_test.go
@@ -3,7 +3,7 @@ NAME
   lex_test.go
 
 DESCRIPTION
-  See Readme.md
+  lex_test.go provides testing for the lexer in lex.go.
 
 AUTHOR
   Dan Kortschak <dan@ausocean.org>