运行训练指令的时候出现找不到图像文件的报错

可能是因为xml转yolo要求的txt代码生成的文件保存的路径不完整，生成的mydata下的三个txt里面的文件路径不完整

修改代码后生成完整路径再次运行没问题了

yolo task=detect mode=train model=yolov8n.pt data=C:\Users\16841\myv8\ultralytics-main\mydata\fall.yaml batch=32 epochs=100 imgsz=640 workers=16 device=0

修改的代码如下

注：一定要把路径和类别改成自己的，这里我的类别是fall

# -*- coding: utf-8 -*-
import xml.etree.ElementTree as ET
import os
from os import listdir, getcwd
from os.path import join, isfile, abspath

sets = ['train', 'test', 'val']
classes = ['fall']

# 进行归一化操作
def convert(size, box):
    dw = 1./size[0]
    dh = 1./size[1]
    x = (box[0] + box[1])/2.0
    y = (box[2] + box[3])/2.0
    w = box[1] - box[0]
    h = box[3] - box[2]
    x = x*dw
    w = w*dwa
    y = y*dh
    h = h*dh
    return (x, y, w, h)


def convert_annotation(image_id, img_path, ann_path):
    in_file = open(join(ann_path, '%s.xml' % (image_id)), encoding='utf-8')
    out_file = open(join(img_path, '%s.txt' % (image_id)), 'w', encoding='utf-8')
    tree = ET.parse(in_file)
    root = tree.getroot()
    size = root.find('size')
    if size is not None:
        w = int(size.find('width').text)
        h = int(size.find('height').text)
        for obj in root.iter('object'):
            difficult = obj.find('difficult').text
            cls = obj.find('name').text
            if cls not in classes or int(difficult) == 1:
                continue
            cls_id = classes.index(cls)
            xmlbox = obj.find('bndbox')
            b = (float(xmlbox.find('xmin').text), float(xmlbox.find('xmax').text), float(xmlbox.find('ymin').text), float(xmlbox.find('ymax').text))
            bb = convert((w, h), b)
            out_file.write(str(cls_id) + " " + " ".join([str(a) for a in bb]) + '\n')

wd = getcwd()
ann_path = join(wd, 'mydata', 'Annotations')
img_path = join(wd, 'mydata', 'images')

for image_set in sets:
    if not os.path.exists(join(wd, 'mydata', 'labels')):
        os.makedirs(join(wd, 'mydata', 'labels'))
    image_ids = open(join(wd, 'mydata', 'ImageSets', '%s.txt' % (image_set))).read().strip().split()
    list_file = open(join(wd, 'mydata', '%s.txt' % (image_set)), 'w')
    for image_id in image_ids:
        full_img_path = abspath(join(img_path, '%s.jpg' % (image_id)))
        list_file.write(full_img_path + '\n')
        convert_annotation(image_id, img_path, ann_path)
    list_file.close()

总结：涉及到路径引用，最好都要绝对路径，尽量避免相对路径