From ee130e23066251776dc64529a5c0d885934dee78 Mon Sep 17 00:00:00 2001
From: Mathieu Malaterre <mathieu.malaterre@gmail.com>
Date: Wed, 26 Mar 2014 11:52:01 +0000
Subject: [PATCH] [trunk] Add small utilities to extract JP2 files from PDF

---
 tests/CMakeLists.txt |   1 +
 tests/pdf2jp2.c      | 127 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 128 insertions(+)
 create mode 100644 tests/pdf2jp2.c

diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index a62ceaf9..64f63e83 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -100,3 +100,4 @@ if(BUILD_JPIP)
 endif()
 
 add_executable(ppm2rgb3 ppm2rgb3.c)
+#add_executable(pdf2jp2 pdf2jp2.c)
diff --git a/tests/pdf2jp2.c b/tests/pdf2jp2.c
new file mode 100644
index 00000000..830cbf4e
--- /dev/null
+++ b/tests/pdf2jp2.c
@@ -0,0 +1,127 @@
+/*
+ * Copyright (c) 2014, Mathieu Malaterre <mathieu.malaterre@voxxl.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * Extract all JP2 files contained within a PDF file.
+ *
+ * Technically you could simply use mutool, eg:
+ *
+ * $ mutool show -be -o obj58.jp2 Bug691816.pdf 58
+ *
+ * to extract a given JP2 file from within a PDF
+ * However it happens sometimes that the PDF is itself corrupted, this tools is
+ * a lame PDF parser which only extract stream contained in JPXDecode box
+ * only work on linux since I need memmem function
+ */
+
+#define _GNU_SOURCE
+#include <string.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <assert.h>
+
+int main(int argc, char *argv[])
+{
+#define NUMJP2 32
+  int i, c = 0;
+  long offets[NUMJP2];
+  char buffer[512];
+#define BUFLEN 4096
+  int cont = 1;
+  FILE *f;
+  size_t nread;
+  char haystack[BUFLEN];
+  const char needle[] = "JPXDecode";
+
+  const size_t nlen = strlen( needle );
+  const size_t flen = BUFLEN - nlen;
+  char *fpos = haystack + nlen;
+  const char *filename;
+  if( argc < 2 ) return 1;
+
+  filename = argv[1];
+
+  memset( haystack, 0, nlen );
+
+  f = fopen( filename, "rb" );
+  while( cont )
+    {
+    const char *ret;
+    size_t hlen;
+    nread = fread(fpos, 1, flen, f);
+    hlen = nlen + nread;
+    ret = memmem( haystack, hlen, needle, nlen);
+    if( ret )
+      {
+      const long cpos = ftell(f);
+      const ptrdiff_t diff = ret - haystack;
+      assert( diff >= 0 );
+      /*fprintf( stdout, "Found it: %lx\n", (ptrdiff_t)cpos - (ptrdiff_t)hlen + diff);*/
+      offets[c++] = (ptrdiff_t)cpos - (ptrdiff_t)hlen + diff;
+      }
+    cont = (nread == flen);
+    memcpy( haystack, haystack + nread, nlen );
+    }
+
+  assert( feof( f ) );
+
+  for( i = 0; i < c; ++i )
+    {
+    int s, len = 0;
+    char *r;
+    const int ret = fseek(f, offets[i], SEEK_SET);
+    assert( ret == 0 );
+    r = fgets(buffer, sizeof(buffer), f);
+    assert( r );
+    /*fprintf( stderr, "DEBUG: %s", r );*/
+    s = sscanf(r, "JPXDecode]/Length  %d/Width %*d/BitsPerComponent %*d/Height %*d", &len);
+    assert( s == 1 );
+      {
+      FILE *jp2;
+      int j;
+      char jp2fn[512];
+      sprintf( jp2fn, "%s.%d.jp2", filename, i );
+      jp2 = fopen( jp2fn, "wb" );
+      for( j = 0; j < len; ++j )
+        {
+        int v = fgetc(f);
+        int ret2 = fputc(v, jp2);
+        assert( ret2 != EOF );
+        }
+      fclose( jp2 );
+#if 0
+      /* TODO need to check we reached endstream */
+      r = fgets(buffer, sizeof(buffer), f);
+      fprintf( stderr, "DEBUG: [%s]", r );
+      r = fgets(buffer, sizeof(buffer), f);
+      fprintf( stderr, "DEBUG: [%s]", r );
+#endif
+      }
+    }
+  fclose(f);
+
+  return 0;
+}