diff --git a/.DS_Store b/.DS_Store index 1799903..2f17559 100644 Binary files a/.DS_Store and b/.DS_Store differ diff --git a/__pycache__/heic_file.cpython-314.pyc b/__pycache__/heic_file.cpython-314.pyc index 1650258..fd440c7 100644 Binary files a/__pycache__/heic_file.cpython-314.pyc and b/__pycache__/heic_file.cpython-314.pyc differ diff --git a/__pycache__/heic_types.cpython-314.pyc b/__pycache__/heic_types.cpython-314.pyc index 50a5690..42b7d47 100644 Binary files a/__pycache__/heic_types.cpython-314.pyc and b/__pycache__/heic_types.cpython-314.pyc differ diff --git a/heic_file.py b/heic_file.py index 203ea85..7d7dcc6 100644 --- a/heic_file.py +++ b/heic_file.py @@ -95,7 +95,11 @@ class HEICFile: primary_id = self.get_primary_item_id() if not primary_id: return None if not self._iref_box: return None - return self._iref_box.references.get(primary_id) + + # 'dimg' (derived image) 是网格布局的标准引用类型 + if 'dimg' in self._iref_box.references: + return self._iref_box.references['dimg'].get(primary_id) + return None def get_image_size(self, item_id: int) -> tuple[int, int] | None: if not (self._iprp_box and self._iprp_box.ipma and self._iprp_box.ipco): return None @@ -152,4 +156,48 @@ class HEICFile: with open(self.filepath, 'rb') as f: f.seek(offset) return f.read() - return None \ No newline at end of file + return None + + def get_thumbnail_data(self) -> bytes | None: + """ + 查找并提取缩略图图像数据 (如果存在)。 + 它会查找一个 'iref' 盒子，其中包含 'thmb' (thumbnail) 引用。 + """ + print("Attempting to extract thumbnail data...") + primary_id = self.get_primary_item_id() + if not primary_id: + print("Error: Could not determine primary item ID.") + return None + + if not self._iref_box: + print("Info: No 'iref' box found, cannot search for thumbnail.") + return None + + # 检查 'thmb' (thumbnail) 引用类型是否存在 + if 'thmb' not in self._iref_box.references: + print("Info: No 'thmb' references found in 'iref' box.") + return None + + # 检查主图像是否有与之关联的缩略图 + if primary_id not in self._iref_box.references['thmb']: + print(f"Info: Primary item ID {primary_id} has no 'thmb' reference.") + return None + + thumbnail_ids = self._iref_box.references['thmb'][primary_id] + if not thumbnail_ids: + print(f"Info: Primary item ID {primary_id} has 'thmb' reference, but no target IDs.") + return None + + # 获取第一个缩略图 ID + thumbnail_id = thumbnail_ids[0] + print(f"Found thumbnail reference: Primary ID {primary_id} -> Thumbnail ID {thumbnail_id}") + + # 使用现有的 get_item_data 来提取它 + thumbnail_data = self.get_item_data(thumbnail_id) + + if thumbnail_data: + print(f"Successfully extracted thumbnail data (Item ID {thumbnail_id}).") + return thumbnail_data + else: + print(f"Error: Failed to get data for thumbnail item ID {thumbnail_id}.") + return None \ No newline at end of file diff --git a/heic_types.py b/heic_types.py index b1b4fc0..aad7d35 100644 --- a/heic_types.py +++ b/heic_types.py @@ -206,8 +206,10 @@ class ItemReferenceEntry: class ItemReferenceBox(Box): def __init__(self, size: int, box_type: str, offset: int, raw_data: bytes): super().__init__(size, box_type, offset, raw_data) - self.references: dict[int, list[int]] = {} + # 结构: {'thmb': {from_id: [to_id, ...]}, 'dimg': {from_id: [to_id, ...]}} + self.references: dict[str, dict[int, list[int]]] = {} self._parse_references() + def _parse_references(self): stream = self.raw_data version_flags = struct.unpack('>I', stream[:4])[0] @@ -215,17 +217,29 @@ class ItemReferenceBox(Box): pos = 4 item_id_size = 4 if version == 1 else 2 while pos < len(stream): - if pos + 8 > len(stream): break + if pos + 8 > len(stream): break # 需要空间来读取 size 和 type ref_box_size = struct.unpack('>I', stream[pos:pos+4])[0] + ref_box_type = stream[pos+4:pos+8].decode('ascii', errors='ignore') + if pos + ref_box_size > len(stream): break + + # 为这种引用类型创建字典 (如果它还不存在) + if ref_box_type not in self.references: + self.references[ref_box_type] = {} + if item_id_size == 4: + if pos + 12 > len(stream): break from_item_id = struct.unpack('>I', stream[pos+8:pos+12])[0] ref_count_pos = pos + 12 else: + if pos + 10 > len(stream): break from_item_id = struct.unpack('>H', stream[pos+8:pos+10])[0] ref_count_pos = pos + 10 + + if ref_count_pos + 2 > len(stream): break reference_count = struct.unpack('>H', stream[ref_count_pos:ref_count_pos+2])[0] to_ids_pos = ref_count_pos + 2 + to_item_ids = [] for _ in range(reference_count): if to_ids_pos + item_id_size > len(stream): break @@ -235,5 +249,6 @@ class ItemReferenceBox(Box): to_id = struct.unpack('>H', stream[to_ids_pos:to_ids_pos+2])[0] to_item_ids.append(to_id) to_ids_pos += item_id_size - self.references[from_item_id] = to_item_ids + + self.references[ref_box_type][from_item_id] = to_item_ids pos += ref_box_size \ No newline at end of file diff --git a/main.py b/main.py index 658f173..14d40ca 100644 --- a/main.py +++ b/main.py @@ -40,6 +40,23 @@ def analyze_and_reconstruct(filename: str): else: print("Failed to reconstruct image.") + # 3. 尝试提取并保存缩略图 + thumbnail_data = heic_file.get_thumbnail_data() + if thumbnail_data: + try: + # 缩略图数据通常是 JPEG 或 HEIC 格式 + # 我们先假设它是 JPEG 并以此后缀保存 + thumb_filename = f"{base_filename}_thumbnail.jpg" + with open(thumb_filename, "wb") as f_thumb: + f_thumb.write(thumbnail_data) + print(f"Successfully saved thumbnail data to: {thumb_filename}") + print(f" (Note: This file might be a JPEG or a small HEIC. Try opening it.)") + except Exception as e: + print(f"Could not save thumbnail file: {e}") + else: + print("No thumbnail data found or extracted.") + + print("\n" + "="*40 + "\n") def main():