diff --git a/codec/mjpeg/extract_test.go b/codec/mjpeg/extract_test.go
new file mode 100644
index 00000000..5d910841
--- /dev/null
+++ b/codec/mjpeg/extract_test.go
@@ -0,0 +1,71 @@
+/*
+DESCRIPTION
+  extract_test.go provides testing for extract.go.
+
+AUTHOR
+  Scott Barnard <scott@ausocean.org>
+
+LICENSE
+  Copyright (C) 2020 the Australian Ocean Lab (AusOcean)
+
+  It is free software: you can redistribute it and/or modify them
+  under the terms of the GNU General Public License as published by the
+  Free Software Foundation, either version 3 of the License, or (at your
+  option) any later version.
+
+  It is distributed in the hope that it will be useful, but WITHOUT
+  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+  for more details.
+
+  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 mjpeg
+
+import (
+	"bytes"
+	"io"
+	"io/ioutil"
+	"testing"
+)
+
+type testReader struct {
+	i int
+}
+
+func (r *testReader) Read(b []byte) (int, error) {
+	if r.i >= len(testPackets) {
+		return 0, io.EOF
+	}
+	copy(b, testPackets[r.i])
+	r.i++
+	return len(testPackets[r.i-1]), nil
+}
+
+func TestExtract(t *testing.T) {
+	const wantPath = "testdata/expect.mjpeg"
+
+	got := &bytes.Buffer{}
+
+	e := NewExtractor()
+
+	r := &testReader{}
+	err := e.Extract(got, r, 0)
+	if err != nil {
+		t.Fatalf("could not extract: %v", err)
+	}
+
+	want, err := ioutil.ReadFile(wantPath)
+	if err != nil {
+		t.Fatalf("could not read file for wanted MJPEG data: %v", err)
+	}
+
+	t.Logf("len(got): %d\n", len(got.Bytes()))
+	t.Logf("len(want): %d\n", len(want))
+
+	if !bytes.Equal(got.Bytes(), want) {
+		t.Error("did not get expected result")
+	}
+}