tesseract: unify logging function

ocrmypdf/tesseract.py

@@ -112,6 +112,22 @@ def get_orientation(input_file, language: list, timeout: float, log):
         return oc
 
 
+def tesseract_log_output(log, stdout, input_file):
+    lines = stdout.splitlines()
+    prefix = "{0:4d}: [tesseract] ".format(page_number(input_file))
+    for line in lines:
+        if line.startswith("Tesseract Open Source"):
+            continue
+        elif line.startswith("Warning in pixReadMem"):
+            continue
+        elif 'diacritics' in line:
+            log.warning(prefix + "lots of diacritics - possibly poor OCR")
+        elif line.startswith('OSD: Weak margin'):
+            log.warning(prefix + "unsure about page orientation")
+        else:
+            log.info(prefix + line.strip())
+
+
 def generate_hocr(input_file, output_hocr, language: list, tessconfig: list,
                   timeout: float, pageinfo_getter, pagesegmode: int, log):
 
@@ -133,10 +149,10 @@ def generate_hocr(input_file, output_hocr, language: list, tessconfig: list,
     p = Popen(args_tesseract, close_fds=True, stdout=PIPE, stderr=STDOUT,
               universal_newlines=True)
     try:
-        stdout, stderr = p.communicate(timeout=timeout)
+        stdout, _ = p.communicate(timeout=timeout)
     except TimeoutExpired:
         p.kill()
-        stdout, stderr = p.communicate()
+        stdout, _ = p.communicate()
         # Generate a HOCR file with no recognized text if tesseract times out
         # Temporary workaround to hocrTransform not being able to function if
         # it does not have a valid hOCR file.
@@ -146,22 +162,7 @@ def generate_hocr(input_file, output_hocr, language: list, tessconfig: list,
                 pageinfo['width_pixels'],
                 pageinfo['height_pixels']))
     else:
-        lines = stdout.splitlines()
-        for line in lines:
-            if line.startswith("Tesseract Open Source"):
-                continue
-            elif line.startswith("Warning in pixReadMemPng"):
-                continue
-            elif 'diacritics' in line:
-                log.warning("{0:4d}: {1} - may indicate poor results".format(
-                    page_number(input_file), line.strip()))
-            elif line.startswith('OSD: Weak margin'):
-                log.warning("{0:4d}: unsure about page orientation".format(
-                    page_number(input_file)))
-            else:
-                log.info("{0:4d}: {1}".format(
-                    page_number(input_file), line.strip()))
-
+        tesseract_log_output(log, stdout, input_file)
         if p.returncode != 0:
             raise CalledProcessError(p.returncode, args_tesseract)
 
@@ -212,17 +213,14 @@ def generate_pdf(input_image, skip_pdf, output_pdf, language: list,
         os.path.splitext(output_pdf)[0],  # Tesseract appends suffix
         'pdf'
     ] + tessconfig)
-    p = Popen(args_tesseract, close_fds=True, stdout=PIPE, stderr=PIPE,
+    p = Popen(args_tesseract, close_fds=True, stdout=PIPE, stderr=STDOUT,
               universal_newlines=True)
 
     try:
-        stdout, stderr = p.communicate(timeout=timeout)
-        if stdout:
-            log.info(stdout)
-        if stderr:
-            log.error(stderr)
+        stdout, _ = p.communicate()
     except TimeoutExpired:
         p.kill()
         log.info("Tesseract - page timed out")
         shutil.copy(skip_pdf, output_pdf)
-
+    else:
+        tesseract_log_output(log, stdout, input_image)