import os import subprocess import json import shutil import logging from pyproj import Transformer import cv2 class ConvertOBJ: def __init__(self, output_dir: str): self.output_dir = output_dir # 用于存储所有grid的UTM范围 self.ref_east = float('inf') self.ref_north = float('inf') # 初始化UTM到WGS84的转换器 self.transformer = Transformer.from_crs( "EPSG:32649", "EPSG:4326", always_xy=True) self.logger = logging.getLogger('UAV_Preprocess.ConvertOBJ') def convert_grid_obj(self, grid_points): """转换每个网格的OBJ文件为OSGB格式""" os.makedirs(os.path.join(self.output_dir, "osgb", "Data"), exist_ok=True) # 以第一个grid的UTM坐标作为参照系 first_grid_id = list(grid_points.keys())[0] first_grid_dir = os.path.join( self.output_dir, f"grid_{first_grid_id[0]}_{first_grid_id[1]}", "project" ) log_file = os.path.join( first_grid_dir, "odm_orthophoto", "odm_orthophoto_log.txt") self.ref_east, self.ref_north = self.read_utm_offset(log_file) for grid_id in grid_points.keys(): try: self._convert_single_grid(grid_id, grid_points) except Exception as e: self.logger.error(f"网格 {grid_id} 转换失败: {str(e)}") self._create_merged_metadata() def _convert_single_grid(self, grid_id, grid_points): """转换单个网格的OBJ文件""" # 构建相关路径 grid_name = f"grid_{grid_id[0]}_{grid_id[1]}" project_dir = os.path.join(self.output_dir, grid_name, "project") texturing_dir = os.path.join(project_dir, "odm_texturing") texturing_dst_dir = os.path.join(project_dir, "odm_texturing_dst") split_obj_dir = os.path.join(texturing_dst_dir, "split_obj") opensfm_dir = os.path.join(project_dir, "opensfm") log_file = os.path.join( project_dir, "odm_orthophoto", "odm_orthophoto_log.txt") os.makedirs(texturing_dst_dir, exist_ok=True) # 修改obj文件z坐标的值 min_25d_z = self.get_min_z_from_obj(os.path.join( project_dir, 'odm_texturing_25d', 'odm_textured_model_geo.obj')) self.modify_z_in_obj(texturing_dir, min_25d_z) # 在新文件夹下，利用UTM偏移量，修改obj文件顶点坐标，纹理文件下采样 utm_offset = self.read_utm_offset(log_file) modified_obj = self.modify_obj_coordinates( texturing_dir, texturing_dst_dir, utm_offset) self.downsample_texture(texturing_dir, texturing_dst_dir) # 将obj文件进行切片 self.logger.info(f"开始切片网格 {grid_id} 的OBJ文件") os.makedirs(split_obj_dir) cmd = ( f"D:\software\Obj2Tiles\Obj2Tiles.exe --stage Splitting --lods 1 --divisions 3 " f"{modified_obj} {split_obj_dir}" ) subprocess.run(cmd, check=True) # 执行格式转换，Linux下osgconv有问题，记得注释掉 self.logger.info(f"开始转换网格 {grid_id} 的OBJ文件") # 先获取split_obj_dir下的所有obj文件 obj_lod_dir = os.path.join(split_obj_dir, "LOD-0") obj_files = [f for f in os.listdir( obj_lod_dir) if f.endswith('.obj')] for obj_file in obj_files: obj_path = os.path.join(obj_lod_dir, obj_file) osgb_file = os.path.splitext(obj_file)[0] + '.osgb' osgb_path = os.path.join(split_obj_dir, osgb_file) # 执行 osgconv 命令 subprocess.run(['osgconv', obj_path, osgb_path], check=True) # 创建OSGB目录结构，复制文件 osgb_base_dir = os.path.join(self.output_dir, "osgb") data_dir = os.path.join(osgb_base_dir, "Data") for obj_file in obj_files: obj_file_name = os.path.splitext(obj_file)[0] tile_dirs = os.path.join(data_dir, f"{obj_file_name}") os.makedirs(tile_dirs, exist_ok=True) shutil.copy2(os.path.join( split_obj_dir, obj_file_name+".osgb"), tile_dirs) def _create_merged_metadata(self): """创建合并后的metadata.xml文件""" # 转换为WGS84经纬度 center_lon, center_lat = self.transformer.transform( self.ref_east, self.ref_north) metadata_content = f""" EPSG:4326 {center_lon},{center_lat},0 Visible """ metadata_file = os.path.join(self.output_dir, "osgb", "metadata.xml") with open(metadata_file, 'w', encoding='utf-8') as f: f.write(metadata_content) def read_utm_offset(self, log_file: str) -> tuple: """读取UTM偏移量""" try: east_offset = None north_offset = None with open(log_file, 'r') as f: lines = f.readlines() for i, line in enumerate(lines): if 'utm_north_offset' in line and i + 1 < len(lines): north_offset = float(lines[i + 1].strip()) elif 'utm_east_offset' in line and i + 1 < len(lines): east_offset = float(lines[i + 1].strip()) if east_offset is None or north_offset is None: raise ValueError("未找到UTM偏移量") return east_offset, north_offset except Exception as e: self.logger.error(f"读取UTM偏移量时发生错误: {str(e)}") raise def modify_obj_coordinates(self, texturing_dir: str, texturing_dst_dir: str, utm_offset: tuple) -> str: """修改obj文件中的顶点坐标，使用相对坐标系""" obj_file = os.path.join( texturing_dir, "odm_textured_model_modified.obj") obj_dst_file = os.path.join( texturing_dst_dir, "odm_textured_model_geo_utm.obj") if not os.path.exists(obj_file): raise FileNotFoundError(f"找不到OBJ文件: {obj_file}") shutil.copy2(os.path.join(texturing_dir, "odm_textured_model_geo.mtl"), os.path.join(texturing_dst_dir, "odm_textured_model_geo.mtl")) east_offset, north_offset = utm_offset self.logger.info( f"UTM坐标偏移：{east_offset - self.ref_east}, {north_offset - self.ref_north}") try: with open(obj_file, 'r') as f_in, open(obj_dst_file, 'w') as f_out: for line in f_in: if line.startswith('v '): # 处理顶点坐标行 parts = line.strip().split() # 使用相对于整体最小UTM坐标的偏移 x = float(parts[1]) + (east_offset - self.ref_east) y = float(parts[2]) + (north_offset - self.ref_north) z = float(parts[3]) f_out.write(f'v {x:.6f} {z:.6f} {-y:.6f}\n') elif line.startswith('vn '): # 处理法线向量 parts = line.split() nx = float(parts[1]) ny = float(parts[2]) nz = float(parts[3]) # 同步反转法线的 Y 轴 new_line = f"vn {nx} {nz} {-ny}\n" f_out.write(new_line) else: # 其他行直接写入 f_out.write(line) return obj_dst_file except Exception as e: self.logger.error(f"修改obj坐标时发生错误: {str(e)}") raise def downsample_texture(self, src_dir: str, dst_dir: str): """复制并重命名纹理文件，对大于100MB的文件进行多次下采样，直到文件小于100MB Args: src_dir: 源纹理目录 dst_dir: 目标纹理目录 """ for file in os.listdir(src_dir): if file.lower().endswith(('.png')): src_path = os.path.join(src_dir, file) dst_path = os.path.join(dst_dir, file) # 检查文件大小（以字节为单位） file_size = os.path.getsize(src_path) if file_size <= 100 * 1024 * 1024: # 如果文件小于等于100MB，直接复制 shutil.copy2(src_path, dst_path) else: # 文件大于100MB，进行下采样 img = cv2.imread(src_path, cv2.IMREAD_UNCHANGED) if_first_ds = True while file_size > 100 * 1024 * 1024: # 大于100MB self.logger.info(f"纹理文件 {file} 大于100MB，进行下采样") if if_first_ds: # 计算新的尺寸（长宽各变为1/4） new_size = (img.shape[1] // 4, img.shape[0] // 4) # 逐步减小尺寸 # 使用双三次插值进行下采样 resized_img = cv2.resize( img, new_size, interpolation=cv2.INTER_CUBIC) if_first_ds = False else: # 计算新的尺寸（长宽各变为1/2） new_size = (img.shape[1] // 2, img.shape[0] // 2) # 逐步减小尺寸 # 使用双三次插值进行下采样 resized_img = cv2.resize( img, new_size, interpolation=cv2.INTER_CUBIC) # 更新文件路径为下采样后的路径 cv2.imwrite(dst_path, resized_img, [ cv2.IMWRITE_PNG_COMPRESSION, 9]) # 更新文件大小和图像 file_size = os.path.getsize(dst_path) img = cv2.imread(dst_path, cv2.IMREAD_UNCHANGED) self.logger.info( f"下采样后文件大小: {file_size / (1024 * 1024):.2f} MB") def get_min_z_from_obj(self, file_path): min_z = float('inf') # 初始值设为无穷大 with open(file_path, 'r') as obj_file: for line in obj_file: # 检查每一行是否是顶点定义（以 'v ' 开头） if line.startswith('v '): # 获取顶点坐标 parts = line.split() # 将z值转换为浮动数字 z = float(parts[3]) # 更新最小z值 if z < min_z: min_z = z return min_z def modify_z_in_obj(self, texturing_dir, min_25d_z): obj_file = os.path.join(texturing_dir, 'odm_textured_model_geo.obj') output_file = os.path.join( texturing_dir, 'odm_textured_model_modified.obj') with open(obj_file, 'r') as f_in, open(output_file, 'w') as f_out: for line in f_in: if line.startswith('v '): # 顶点坐标行 parts = line.strip().split() x = float(parts[1]) y = float(parts[2]) z = float(parts[3]) if z < min_25d_z: z = min_25d_z f_out.write(f"v {x} {y} {z}\n") else: f_out.write(line)