imghdr
— 确定图像类型
¶
源代码： Lib/imghdr.py
imghdr
module determines the type of image contained in a file or byte stream.
imghdr
module defines the following function:
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.
3.6 版改变： 接受 像路径对象 .
The following image types are recognized, as listed below with the return value from
what()
:
| Value | Image format |
|---|---|
'rgb'
|
SGI ImgLib Files |
'gif'
|
GIF 87a and 89a Files |
'pbm'
|
Portable Bitmap Files |
'pgm'
|
Portable Graymap Files |
'ppm'
|
Portable Pixmap Files |
'tiff'
|
TIFF Files |
'rast'
|
Sun Raster Files |
'xbm'
|
X Bitmap Files |
'jpeg'
|
JPEG data in JFIF or Exif formats |
'bmp'
|
BMP files |
'png'
|
Portable Network Graphics (便携式网络图形) |
'webp'
|
WebP files |
'exr'
|
OpenEXR Files |
3.5 版新增： exr and webp formats were added.
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'