完成训练模块的转移

yolov5/utils/downloads.py

@@ -0,0 +1,136 @@
+# Ultralytics 🚀 AGPL-3.0 License - https://ultralytics.com/license
+"""Download utils."""
+
+import logging
+import subprocess
+import urllib
+from pathlib import Path
+
+import requests
+import torch
+
+
+def is_url(url, check=True):
+    """Determines if a string is a URL and optionally checks its existence online, returning a boolean."""
+    try:
+        url = str(url)
+        result = urllib.parse.urlparse(url)
+        assert all([result.scheme, result.netloc])  # check if is url
+        return (urllib.request.urlopen(url).getcode() == 200) if check else True  # check if exists online
+    except (AssertionError, urllib.request.HTTPError):
+        return False
+
+
+def gsutil_getsize(url=""):
+    """
+    Returns the size in bytes of a file at a Google Cloud Storage URL using `gsutil du`.
+
+    Returns 0 if the command fails or output is empty.
+    """
+    output = subprocess.check_output(["gsutil", "du", url], shell=True, encoding="utf-8")
+    return int(output.split()[0]) if output else 0
+
+
+def url_getsize(url="https://ultralytics.com/images/bus.jpg"):
+    """Returns the size in bytes of a downloadable file at a given URL; defaults to -1 if not found."""
+    response = requests.head(url, allow_redirects=True)
+    return int(response.headers.get("content-length", -1))
+
+
+def curl_download(url, filename, *, silent: bool = False) -> bool:
+    """Download a file from a url to a filename using curl."""
+    silent_option = "sS" if silent else ""  # silent
+    proc = subprocess.run(
+        [
+            "curl",
+            "-#",
+            f"-{silent_option}L",
+            url,
+            "--output",
+            filename,
+            "--retry",
+            "9",
+            "-C",
+            "-",
+        ]
+    )
+    return proc.returncode == 0
+
+
+def safe_download(file, url, url2=None, min_bytes=1e0, error_msg=""):
+    """
+    Downloads a file from a URL (or alternate URL) to a specified path if file is above a minimum size.
+
+    Removes incomplete downloads.
+    """
+    from utils.general import LOGGER
+
+    file = Path(file)
+    assert_msg = f"Downloaded file '{file}' does not exist or size is < min_bytes={min_bytes}"
+    try:  # url1
+        LOGGER.info(f"Downloading {url} to {file}...")
+        torch.hub.download_url_to_file(url, str(file), progress=LOGGER.level <= logging.INFO)
+        assert file.exists() and file.stat().st_size > min_bytes, assert_msg  # check
+    except Exception as e:  # url2
+        if file.exists():
+            file.unlink()  # remove partial downloads
+        LOGGER.info(f"ERROR: {e}\nRe-attempting {url2 or url} to {file}...")
+        # curl download, retry and resume on fail
+        curl_download(url2 or url, file)
+    finally:
+        if not file.exists() or file.stat().st_size < min_bytes:  # check
+            if file.exists():
+                file.unlink()  # remove partial downloads
+            LOGGER.info(f"ERROR: {assert_msg}\n{error_msg}")
+        LOGGER.info("")
+
+
+def attempt_download(file, repo="ultralytics/yolov5", release="v7.0"):
+    """Downloads a file from GitHub release assets or via direct URL if not found locally, supporting backup
+    versions.
+    """
+    from utils.general import LOGGER
+
+    def github_assets(repository, version="latest"):
+        """Fetches GitHub repository release tag and asset names using the GitHub API."""
+        if version != "latest":
+            version = f"tags/{version}"  # i.e. tags/v7.0
+        response = requests.get(f"https://api.github.com/repos/{repository}/releases/{version}").json()  # github api
+        return response["tag_name"], [x["name"] for x in response["assets"]]  # tag, assets
+
+    file = Path(str(file).strip().replace("'", ""))
+    if not file.exists():
+        # URL specified
+        name = Path(urllib.parse.unquote(str(file))).name  # decode '%2F' to '/' etc.
+        if str(file).startswith(("http:/", "https:/")):  # download
+            url = str(file).replace(":/", "://")  # Pathlib turns :// -> :/
+            file = name.split("?")[0]  # parse authentication https://url.com/file.txt?auth...
+            if Path(file).is_file():
+                LOGGER.info(f"Found {url} locally at {file}")  # file already exists
+            else:
+                safe_download(file=file, url=url, min_bytes=1e5)
+            return file
+
+        # GitHub assets
+        assets = [f"yolov5{size}{suffix}.pt" for size in "nsmlx" for suffix in ("", "6", "-cls", "-seg")]  # default
+        try:
+            tag, assets = github_assets(repo, release)
+        except Exception:
+            try:
+                tag, assets = github_assets(repo)  # latest release
+            except Exception:
+                try:
+                    tag = subprocess.check_output("git tag", shell=True, stderr=subprocess.STDOUT).decode().split()[-1]
+                except Exception:
+                    tag = release
+
+        if name in assets:
+            file.parent.mkdir(parents=True, exist_ok=True)  # make parent dir (if required)
+            safe_download(
+                file,
+                url=f"https://github.com/{repo}/releases/download/{tag}/{name}",
+                min_bytes=1e5,
+                error_msg=f"{file} missing, try downloading from https://github.com/{repo}/releases/{tag}",
+            )
+
+    return str(file)