Fix an off-by-one error and a memory leak

src/zbar_pipeline.c

@@ -176,7 +176,7 @@ process_image(MPPipeline *pipeline, MPZBarImage **_image)
 	size_t i = 0;
 	for (int y = 0; y < image->height; y += 2) {
 		for (int x = 0; x < image->width; x += 2) {
-			data[++i] = image->data[x + image->width * y];
+			data[i++] = image->data[x + image->width * y];
 		}
 	}
 
@@ -184,7 +184,7 @@ process_image(MPPipeline *pipeline, MPZBarImage **_image)
 	zbar_image_t *zbar_image = zbar_image_create();
 	zbar_image_set_format(zbar_image, zbar_fourcc('Y', '8', '0', '0'));
 	zbar_image_set_size(zbar_image, width, height);
-	zbar_image_set_data(zbar_image, data, width * height * sizeof(uint8_t), NULL);
+	zbar_image_set_data(zbar_image, data, width * height * sizeof(uint8_t), zbar_image_free_data);
 
 	int res = zbar_scan_image(scanner, zbar_image);
 	assert(res >= 0);