diff --git a/Makefile.am b/Makefile.am
index 42198e0..d21d560 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -17,6 +17,7 @@ rastertobrlaser_SOURCES = \
 	src/debug.cc \
 	src/job.h \
 	src/job.cc \
+	src/block.h \
 	src/line.h \
 	src/line.cc
 rastertobrlaser_CPPFLAGS = $(CUPS_CFLAGS)
diff --git a/src/block.h b/src/block.h
new file mode 100644
index 0000000..cd3a48e
--- /dev/null
+++ b/src/block.h
@@ -0,0 +1,63 @@
+// This file is part of the brlaser printer driver.
+//
+// Copyright 2013 Peter De Wachter
+//
+// brlaser is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 2 of the License, or
+// (at your option) any later version.
+//
+// brlaser 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 brlaser.  If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef BLOCK_H
+#define BLOCK_H
+
+#include <assert.h>
+#include <stdio.h>
+#include <vector>
+
+class block {
+ public:
+  block(): line_bytes_(0) {
+  }
+
+  void add_line(std::vector<uint8_t> &&line) {
+    assert(!line.empty());
+    assert(line_fits(line.size()));
+    line_bytes_ += line.size();
+    lines_.push_back(line);
+  }
+
+  bool line_fits(unsigned size) {
+    return lines_.size() != max_lines_per_block_
+      && line_bytes_ + size < max_block_size_;
+  }
+
+  void flush(FILE *f) {
+    if (line_bytes_) {
+      fprintf(f, "%dw%c%c",
+              line_bytes_ + 2, 0,
+              static_cast<int>(lines_.size()));
+      for (auto &line : lines_) {
+        fwrite(line.data(), 1, line.size(), f);
+      }
+      line_bytes_ = 0;
+      lines_.clear();
+    }
+  }
+
+ private:
+  static const unsigned max_block_size_ = 16350;
+  static const unsigned max_lines_per_block_ = 128;
+
+  std::vector<std::vector<uint8_t>> lines_;
+  int line_bytes_;
+};
+
+#endif  // BLOCK_H
diff --git a/src/job.cc b/src/job.cc
index 535d60d..cc8e201 100644
--- a/src/job.cc
+++ b/src/job.cc
@@ -20,49 +20,8 @@
 #include <algorithm>
 #include <vector>
 #include "line.h"
+#include "block.h"
 
-using std::vector;
-
-namespace {
-
-class block {
- public:
-  block(): line_bytes_(0) {
-  }
-
-  void add_line(vector<uint8_t> &&line) {
-    assert(!line.empty());
-    line_bytes_ += line.size();
-    lines_.push_back(line);
-  }
-
-  bool line_fits(unsigned size) {
-    return lines_.size() != max_lines_per_block_
-      && line_bytes_ + size < max_block_size_;
-  }
-
-  void flush(FILE *f) {
-    if (line_bytes_) {
-      fprintf(f, "%dw%c%c",
-              line_bytes_ + 2, 0,
-              static_cast<int>(lines_.size()));
-      for (auto &line : lines_) {
-        fwrite(line.data(), 1, line.size(), f);
-      }
-      line_bytes_ = 0;
-      lines_.clear();
-    }
-  }
-
- private:
-  static const unsigned max_block_size_ = 16350;
-  static const unsigned max_lines_per_block_ = 128;
-
-  vector<vector<uint8_t>> lines_;
-  int line_bytes_;
-};
-
-}  // namespace
 
 job::job(FILE *out, const std::string &job_name)
     : out_(out),
@@ -126,8 +85,8 @@ void job::encode_page(const page_params &page_params,
     write_page_header();
   }
 
-  vector<uint8_t> line(linesize);
-  vector<uint8_t> reference(linesize);
+  std::vector<uint8_t> line(linesize);
+  std::vector<uint8_t> reference(linesize);
   block block;
 
   if (!nextline(line.data())) {
@@ -141,7 +100,7 @@ void job::encode_page(const page_params &page_params,
   fputs("\033*b1030m", out_);
 
   for (int i = 1; i < lines && nextline(line.data()); ++i) {
-    vector<uint8_t> encoded = encode_line(line, reference);
+    std::vector<uint8_t> encoded = encode_line(line, reference);
     if (!block.line_fits(encoded.size())) {
       block.flush(out_);
     }