Python使用filetype精确判断文件类型
判断文件类型在开发中非常常见的需求,怎样才能准确的判断文件类型呢?首先大家想到的是文件的后缀,但是非常遗憾的是这种方法是非常不靠谱的,因为文件的后缀是可以随意更改的,而python中有个小插件可以实现,下面我们就来详细探讨下
filetype.py
Small and dependency free Python package to infer file type and MIME type checking the magic numbers signature of a file or buffer.
This is a Python port from filetype Go package. Works in Python 3 .
一个小巧自由开放Python开发包,主要用来获得文件类型。包要求Python 3.
功能特色
•简单友好的API
•支持宽范围文件类型
•提供文件扩展名和MIME类型判断
•文件的MIME类型扩展新增
•通过文件(图像、视频、音频…)简单分析
•可插拔:添加新的自定义类型的匹配
•快,即使处理大文件
•只需要前261个字节表示的最大文件头,这样你就可以通过一个单字节
•依赖自由(只是Python代码,没有C的扩展,没有libmagic绑定)
•跨平台文件识别
安装
pip install filetype
API
详情请查看 annotated API reference .
实例
简单的文件类型识别
支持类型
图片
• jpg – image/jpeg
• png – image/png
• gif – image/gif
• webp – image/webp
• cr2 – image/x-canon-cr2
• tif – image/tiff
• bmp – image/bmp
• jxr – image/vnd.ms-photo
• psd – image/vnd.adobe.photoshop
• ico – image/x-icon
视频
• mp4 – video/mp4
• m4v – video/x-m4v
• mkv – video/x-matroska
• webm – video/webm
• mov – video/quicktime
• avi – video/x-msvideo
• wmv – video/x-ms-wmv
• mpg – video/mpeg
• flv – video/x-flv
音频
• mid – audio/midi
• mp3 –
• m4a – audio/m4a
• ogg – audio/ogg
• flac – audio/x-flac
• wav – audio/x-wav
• amr – audio/amr
资料库
• epub – application/epub zip
• zip – application/zip
• tar – application/x-tar
• rar – application/x-rar-compressed
• gz – application/gzip
• bz2 – application/x-bzip2
• 7z – application/x-7z-compressed
• xz – application/x-xz
• pdf – application/pdf
• exe – application/x-msdownload
• swf – application/x-shockwave-flash
• rtf – application/rtf
• eot – application/octet-stream
• ps – application/postscript
• sqlite – application/x-sqlite3
• nes – application/x-nintendo-nes-rom
• crx – application/x-google-chrome-extension
• cab – application/vnd.ms-cab-compressed
• deb – application/x-deb
• ar – application/x-unix-archive
• Z – application/x-compress
• lz – application/x-lzip
字体
• woff – application/font-woff
• woff2 – application/font-woff
• ttf – application/font-sfnt
• otf – application/font-sfnt
基准测试
使用链接中的文件进行测试,你可以点击获得到它: real files .
Environment: OSX x64 i7 2.7 Ghz
------------------------------------------------------------------------------------------ benchmark: 7 tests ------------------------------------------------------------------------------------------
Name (time in ns) Min Max Mean StdDev Median IQR Outliers(*) Rounds Iterations
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_infer_image_from_bytes 357.6279 (1.0) 29,166.5395 (1.0) 1,642.3360 (1.0) 380.9934 (1.0) 1,509.9843 (1.0) 158.9457 (1.0) 9095;13752 102301 6
test_infer_audio_from_bytes 953.6743 (2.67) 96,082.6874 (3.29) 16,534.5880 (10.07) 3,002.1143 (7.88) 15,974.0448 (10.58) 953.6743 (6.00) 4514;6051 41528 1
test_infer_video_from_bytes 13,828.2776 (38.67) 272,989.2731 (9.36) 16,151.3144 (9.83) 3,361.2320 (8.82) 15,020.3705 (9.95)