diff --git a/mineru/backend/hybrid/hybrid_model_output_to_middle_json.py b/mineru/backend/hybrid/hybrid_model_output_to_middle_json.py index f1a46296..06821c64 100644 --- a/mineru/backend/hybrid/hybrid_model_output_to_middle_json.py +++ b/mineru/backend/hybrid/hybrid_model_output_to_middle_json.py @@ -20,6 +20,10 @@ from mineru.utils.cut_image import cut_image_and_table from mineru.utils.enum_class import ContentType, BlockType from mineru.utils.hash_utils import bytes_md5 from mineru.utils.ocr_utils import OcrConfidence, rotate_vertical_crop_if_needed +from mineru.utils.span_pre_proc import ( + _clear_post_ocr_fallback, + _restore_post_ocr_fallback, +) from mineru.utils.title_level_postprocess import apply_title_leveling_to_pdf_info from mineru.utils.pdfium_guard import close_pdfium_child, close_pdfium_document, pdfium_guard from mineru.version import __version__ @@ -152,6 +156,9 @@ def _apply_post_ocr(pdf_info_list, hybrid_pipeline_model): if ocr_score > OcrConfidence.min_confidence: span['content'] = ocr_text span['score'] = float(f"{ocr_score:.3f}") + _clear_post_ocr_fallback(span) + elif _restore_post_ocr_fallback(span): + continue else: span['content'] = '' span['score'] = 0.0 diff --git a/mineru/backend/pipeline/model_json_to_middle_json.py b/mineru/backend/pipeline/model_json_to_middle_json.py index ebf1212a..5c4cc9b9 100644 --- a/mineru/backend/pipeline/model_json_to_middle_json.py +++ b/mineru/backend/pipeline/model_json_to_middle_json.py @@ -19,6 +19,10 @@ from mineru.utils.ocr_utils import OcrConfidence, rotate_vertical_crop_if_needed from mineru.version import __version__ from mineru.utils.hash_utils import bytes_md5 from mineru.utils.pdfium_guard import close_pdfium_child, close_pdfium_document, pdfium_guard +from mineru.utils.span_pre_proc import ( + _clear_post_ocr_fallback, + _restore_post_ocr_fallback, +) def page_model_info_to_page_info(page_model_info, image_dict, page, image_writer, page_index, ocr_enable=False): @@ -245,6 +249,9 @@ def _apply_post_ocr(pdf_info_list, lang=None): if ocr_score > OcrConfidence.min_confidence: span['content'] = ocr_text span['score'] = float(f"{ocr_score:.3f}") + _clear_post_ocr_fallback(span) + elif _restore_post_ocr_fallback(span): + continue else: span['content'] = '' span['score'] = 0.0 diff --git a/mineru/utils/span_pre_proc.py b/mineru/utils/span_pre_proc.py index ec0f4288..cdb77694 100644 --- a/mineru/utils/span_pre_proc.py +++ b/mineru/utils/span_pre_proc.py @@ -15,6 +15,15 @@ from mineru.utils.pdf_text_tool import get_lines_from_chars, get_page_chars from mineru.utils.pdfium_guard import close_pdfium_child, pdfium_guard MAX_NATIVE_TEXT_CHARS_PER_PAGE = 65535 +PRIVATE_USE_AREA_START = 0xE000 +PRIVATE_USE_AREA_END = 0xF8FF +PRIVATE_USE_TEXT_COUNT_THRESHOLD = 2 +PRIVATE_USE_TEXT_RATIO_THRESHOLD = 0.05 +PRIVATE_USE_TEXT_RUN_THRESHOLD = 2 +POST_OCR_FALLBACK_CONTENT_KEY = '_post_ocr_fallback_content' +POST_OCR_FALLBACK_SCORE_KEY = '_post_ocr_fallback_score' +POST_OCR_REASON_KEY = '_post_ocr_reason' +POST_OCR_REASON_PRIVATE_USE_TEXT = 'private_use_text' def __replace_ligatures(text: str): @@ -141,6 +150,8 @@ def _prepare_post_ocr_spans(need_ocr_spans, spans, pil_img, scale): span_img = cv2.cvtColor(np.array(span_pil_img), cv2.COLOR_RGB2BGR) # 计算span的对比度，低于0.17的span不进行ocr，等于0.17的临界框保留给后置OCR。 if calculate_contrast(span_img, img_mode='bgr') < 0.17: + if _restore_post_ocr_fallback(span): + continue if span in spans: spans.remove(span) continue @@ -267,9 +278,18 @@ def fill_char_in_spans(spans, all_chars, median_span_height): need_ocr_spans = [] for span in spans: + private_use_signal = _get_private_use_text_signal(span['chars']) + should_post_ocr_private_use = _should_fallback_to_post_ocr_for_private_use_text( + private_use_signal + ) chars_to_content(span) + if should_post_ocr_private_use and span.get('content'): + span[POST_OCR_FALLBACK_CONTENT_KEY] = span['content'] + span[POST_OCR_FALLBACK_SCORE_KEY] = span.get('score', 1.0) + span[POST_OCR_REASON_KEY] = POST_OCR_REASON_PRIVATE_USE_TEXT + need_ocr_spans.append(span) # 有的span中虽然没有字但有一两个空的占位符，用宽高和content长度过滤 - if len(span['content']) * span['height'] < span['width'] * 0.5: + elif len(span['content']) * span['height'] < span['width'] * 0.5: # logger.info(f"maybe empty span: {len(span['content'])}, {span['height']}, {span['width']}") need_ocr_spans.append(span) del span['height'], span['width'] @@ -284,6 +304,79 @@ SCRIPT_BODY_HEIGHT_RATIO = 0.9 SCRIPT_CENTER_TOLERANCE_RATIO = 0.12 +def _is_private_use_char(char: str) -> bool: + """判断单个字符是否落在 Unicode 私用区，用于识别字体映射异常。""" + return ( + len(char) == 1 + and PRIVATE_USE_AREA_START <= ord(char) <= PRIVATE_USE_AREA_END + ) + + +def _get_private_use_text_signal(chars): + """统计 span 字符中的私用区信号，供局部后置 OCR 决策使用。""" + pua_count = 0 + text_char_count = 0 + current_pua_run = 0 + max_pua_run = 0 + + for char in chars: + for text_char in char.get('char', ''): + if text_char.isspace(): + current_pua_run = 0 + continue + + text_char_count += 1 + if _is_private_use_char(text_char): + pua_count += 1 + current_pua_run += 1 + max_pua_run = max(max_pua_run, current_pua_run) + else: + current_pua_run = 0 + + pua_ratio = 0.0 + if text_char_count > 0: + pua_ratio = pua_count / text_char_count + + return { + 'pua_count': pua_count, + 'text_char_count': text_char_count, + 'pua_ratio': pua_ratio, + 'max_pua_run': max_pua_run, + } + + +def _should_fallback_to_post_ocr_for_private_use_text(signal) -> bool: + """连续或高占比 PUA 才转后置 OCR，降低孤立私用符号误召回。""" + pua_count = signal['pua_count'] + if pua_count < PRIVATE_USE_TEXT_COUNT_THRESHOLD: + return False + + return ( + signal['max_pua_run'] >= PRIVATE_USE_TEXT_RUN_THRESHOLD + or signal['pua_ratio'] >= PRIVATE_USE_TEXT_RATIO_THRESHOLD + ) + + +def _clear_post_ocr_fallback(span): + """清理后置 OCR 内部兜底字段，避免进入最终 middle-json 输出。""" + span.pop(POST_OCR_FALLBACK_CONTENT_KEY, None) + span.pop(POST_OCR_FALLBACK_SCORE_KEY, None) + span.pop(POST_OCR_REASON_KEY, None) + + +def _restore_post_ocr_fallback(span) -> bool: + """在后置 OCR 无法使用时恢复原始文本兜底，返回是否已恢复。""" + if POST_OCR_FALLBACK_CONTENT_KEY not in span: + _clear_post_ocr_fallback(span) + return False + + span['content'] = span[POST_OCR_FALLBACK_CONTENT_KEY] + if POST_OCR_FALLBACK_SCORE_KEY in span: + span['score'] = span[POST_OCR_FALLBACK_SCORE_KEY] + _clear_post_ocr_fallback(span) + return True + + def calculate_char_in_span(char_bbox, span_bbox, char, span_height_ratio=Span_Height_Ratio): char_center_x = (char_bbox[0] + char_bbox[2]) / 2 char_center_y = (char_bbox[1] + char_bbox[3]) / 2