Return only asked symbology

By default zbar is configured to detect some symbologies, so we need
to disable them before selecting the desired one.

(closes #10)

ChangeLog.rst

@@ -4,8 +4,7 @@ ChangeLog
 1.1.1 (unreleased)
 ------------------
 
-- Nothing changed yet.
-
+- Only return asked symbologie
 
 1.1.0 (2017-01-24)
 ------------------

src/zbarlight/__init__.py

@@ -4,13 +4,17 @@
 from PIL import Image
 import pkg_resources
 
-from ._zbarlight import zbar_code_scanner
+from ._zbarlight import Symbologies, zbar_code_scanner
 
 
 __version__ = pkg_resources.get_distribution('zbarlight').version
 __ALL__ = ['scan_codes', 'qr_code_scanner']
 
 
+class UnknownSymbologieError(Exception):
+    pass
+
+
 def scan_codes(code_type, image):
     """Get *code_type* codes from a PIL Image
 
@@ -35,7 +39,10 @@ def scan_codes(code_type, image):
     converted_image = image.convert('L')  # Convert image to gray scale (8 bits per pixel).
     raw = converted_image.tobytes()  # Get image data.
     width, height = converted_image.size  # Get image size.
-    return zbar_code_scanner('{0}.enable'.format(code_type).encode(), raw, width, height)
+    symbologie = Symbologies.get(code_type.upper())
+    if not symbologie:
+        raise UnknownSymbologieError('Unknown Symbologie: %s' % code_type)
+    return zbar_code_scanner(symbologie, raw, width, height)
 
 
 def qr_code_scanner(image, width, height):
@@ -54,7 +61,7 @@ def qr_code_scanner(image, width, height):
         The QR code value or None
     """
     warnings.warn('qr_code_scanner() is deprecated use scan_codes() instead.', DeprecationWarning)
-    result = zbar_code_scanner(b'qrcode.enable', image, width, height)
+    result = zbar_code_scanner(Symbologies['QRCODE'], image, width, height)
     if isinstance(result, list) and len(result) == 1:
         return result[0]
     return None

src/zbarlight/_zbarlight.c

@@ -13,7 +13,7 @@
 
 /* Extract QR code from raw image (using zbar) */
 static char** _zbar_code_scanner(
-    const char *config_str,
+    const int symbologie,
     const void *raw_image_data,
     unsigned long raw_image_data_length,
     unsigned int width,
@@ -24,7 +24,8 @@ static char** _zbar_code_scanner(
     char **data = NULL;
 
     zbar_image_scanner_t *scanner = zbar_image_scanner_create();
-    zbar_image_scanner_parse_config(scanner, config_str);
+    zbar_image_scanner_set_config(scanner, 0, ZBAR_CFG_ENABLE, 0); /* disable all symbologies */
+    zbar_image_scanner_set_config(scanner, symbologie, ZBAR_CFG_ENABLE, 1);
 
     zbar_image_t *image = zbar_image_create();
     zbar_image_set_format(image, format);
@@ -55,20 +56,20 @@ static char** _zbar_code_scanner(
 /* Python wrapper for _zbar_code_scanner() */
 static PyObject* zbar_code_scanner(PyObject *self, PyObject *args) {
     PyObject *python_image = NULL;
-    char *config_str = NULL;
+    int symbologie = 0;
     char *raw_image_data = NULL;
     Py_ssize_t raw_image_data_length = 0;
     unsigned int width = 0;
     unsigned int height = 0;
     char **result = NULL;
     PyObject *data = NULL;
 
-    if (!PyArg_ParseTuple(args, "SSII", &config_str, &python_image, &width, &height)) {
+    if (!PyArg_ParseTuple(args, "ISII", &symbologie, &python_image, &width, &height)) {
         return NULL;
     }
     PyBytes_AsStringAndSize(python_image, &raw_image_data, &raw_image_data_length);
 
-    result = _zbar_code_scanner(config_str, raw_image_data, raw_image_data_length, width, height);
+    result = _zbar_code_scanner(symbologie, raw_image_data, raw_image_data_length, width, height);
     if (result == NULL) {
         Py_RETURN_NONE;
     }
@@ -113,7 +114,24 @@ static struct PyModuleDef zbarlight_moduledef = {
 #endif
 
 PyObject* PyInit__zbarlight(void) { /* Python 3 way */
-    return PY_INIT_FCT();
+    PyObject* module = PY_INIT_FCT();
+    PyObject * symbologies = Py_BuildValue(
+        "{s:i,s:i,s:i,s:i,s:i,s:i,s:i,s:i,s:i,s:i,s:i}",
+        "EAN8", ZBAR_EAN8,
+        "UPCE", ZBAR_UPCE,
+        "ISBN10", ZBAR_ISBN10,
+        "UPCA", ZBAR_UPCA,
+        "EAN13", ZBAR_EAN13,
+        "ISBN13", ZBAR_ISBN13,
+        "I25", ZBAR_I25,
+        "CODE39", ZBAR_CODE39,
+        "PDF417", ZBAR_PDF417,
+        "QRCODE", ZBAR_QRCODE,
+        "CODE128", ZBAR_CODE128
+    );
+
+    PyModule_AddObject(module, "Symbologies", symbologies);
+    return module;
 }
 
 void init_zbarlight(void) { /* Python 2 way */

tests/test_scan_codes.py

@@ -40,7 +40,22 @@ def test_two_qr_code(self):
 
     def test_one_qr_code_and_one_ean(self):
         image = self.get_image('one_qr_code_and_one_ean')
+
+        # Only read QRcode
         self.assertEqual(
             sorted(zbarlight.scan_codes('qrcode', image)),
             sorted([b'zbarlight test qr code']),
         )
+
+        # Only read EAN code
+        self.assertEqual(
+            sorted(zbarlight.scan_codes('ean13', image)),
+            sorted([b'0012345678905']),
+        )
+
+    def test_unknown_symbology(self):
+        image = self.get_image('no_qr_code')
+        self.assertRaises(
+            zbarlight.UnknownSymbologieError,
+            zbarlight.scan_codes, 'not-a-zbar-symbologie', image,
+        )