imghdr
— 确定图像类型
¶
源代码： Lib/imghdr.py
The
imghdr
模块确定文件或字节流中包含的图像类型。
The
imghdr
模块定义以下函数：
imghdr.
what
(
filename
,
h=None
)
¶
Tests the image data contained in the file named by filename , and returns a string describing the image type. If optional h is provided, the filename is ignored and h is assumed to contain the byte stream to test.
The following image types are recognized, as listed below with the return value from
what()
:
| 值 | 图像格式 |
|---|---|
'rgb'
|
SGI ImgLib 文件 |
'gif'
|
GIF 87a 和 89a 文件 |
'pbm'
|
PBM (便携式位图) 文件 |
'pgm'
|
PGM (便携式灰度图) 文件 |
'ppm'
|
PPM (便携式像素图) 文件 |
'tiff'
|
TIFF 文件 |
'rast'
|
Sun 光栅文件 |
'xbm'
|
XBM (X 位图) 文件 |
'jpeg'
|
JPEG data in JFIF or Exif formats |
'bmp'
|
BMP 文件 |
'png'
|
PNG (便携式网络图形) |
You can extend the list of file types
imghdr
can recognize by appending to this variable:
imghdr.
tests
¶
A list of functions performing the individual tests. Each function takes two arguments: the byte-stream and an open file-like object. When
what()
is called with a byte-stream, the file-like object will be
None
.
The test function should return a string describing the image type if the test succeeded, or
None
if it failed.
范例：
>>> import imghdr >>> imghdr.what('bass.gif') 'gif'