[formrecognizer] adjust text angle to fit in specified interval (#12248)

* adjust text angle to fit in specified interval

* fix testcase expression

Author: kristapratico

sdk/formrecognizer/azure-ai-formrecognizer/CHANGELOG.md

@@ -1,13 +1,18 @@
 # Change Log azure-ai-formrecognizer
 
 ## 1.0.0b4 (Unreleased)
+
 **Breaking Changes**
 
 - Remove `RecognizedReceipts` Class.
 - `begin_recognize_receipts` and `begin_recognize_receipts_from_url` now return `RecognizedForm`.
 - `requested_on` renamed to `training_started_on` and `completed_on` renamed to `training_completed_on` on `CustomFormModel`
 and `CustomFormModelInfo`
 
+**Fixes and improvements**
+
+- Fixes a bug where `text_angle` was being returned out of the specified interval (-180, 180] 
+
 ## 1.0.0b3 (2020-06-10)
 
 **Breaking Changes**

sdk/formrecognizer/azure-ai-formrecognizer/azure/ai/formrecognizer/_models.py

@@ -20,6 +20,14 @@ def adjust_confidence(score):
     return score
 
 
+def adjust_text_angle(text_angle):
+    """Adjust to (-180, 180]
+    """
+    if text_angle > 180:
+        text_angle -= 360
+    return text_angle
+
+
 def get_elements(field, read_result):
     text_elements = []
 
@@ -327,7 +335,7 @@ def __init__(self, **kwargs):
     def _from_generated(cls, read_result):
         return [cls(
             page_number=page.page,
-            text_angle=page.angle,
+            text_angle=adjust_text_angle(page.angle),
             width=page.width,
             height=page.height,
             unit=page.unit,

sdk/formrecognizer/azure-ai-formrecognizer/azure/ai/formrecognizer/_response_handlers.py

@@ -13,7 +13,8 @@
     FormTable,
     FormTableCell,
     FormPageRange,
-    RecognizedForm
+    RecognizedForm,
+    adjust_text_angle
 )
 
 
@@ -70,7 +71,7 @@ def prepare_content_result(response):
     for idx, page in enumerate(read_result):
         form_page = FormPage(
             page_number=page.page,
-            text_angle=page.angle,
+            text_angle=adjust_text_angle(page.angle),
             width=page.width,
             height=page.height,
             unit=page.unit,

sdk/formrecognizer/azure-ai-formrecognizer/tests/testcase.py

@@ -164,7 +164,10 @@ def assertFormPagesTransformCorrect(self, pages, actual_read, page_result=None,
             if hasattr(page, "pages"):  # this is necessary for how unlabeled forms are structured
                 page = page.pages[0]
             self.assertEqual(page.page_number, actual_page.page)
-            self.assertEqual(page.text_angle, actual_page.angle)
+            if actual_page.angle <= 180:
+                self.assertEqual(page.text_angle, actual_page.angle)
+            if actual_page.angle > 180:
+                self.assertEqual(page.text_angle, actual_page.angle - 360)
             self.assertEqual(page.width, actual_page.width)
             self.assertEqual(page.height, actual_page.height)
             self.assertEqual(page.unit, actual_page.unit)