Issue 37629: Imghdr doesnt recognise some jpeg

➜

This issue tracker has been migrated to GitHub, and is currently read-only.
For more information, see the GitHub FAQs in the Python's Developer Guide.

This issue has been migrated to GitHub: https://github.com/python/cpython/issues/81810

classification

Title:	Imghdr doesnt recognise some jpeg
Type:	behavior	Stage:	resolved
Components:	Library (Lib)	Versions:	Python 3.7

process

Status:	closed	Resolution:	duplicate
Dependencies:		Superseder:
Assigned To:		Nosy List:	Krishna Oza, pchopin, vstinner
Priority:	normal	Keywords:

Created on 2019-07-19 09:50 by pchopin, last changed 2022-04-11 14:59 by admin. This issue is now closed.

Pull Requests
URL	Status	Linked	Edit
PR 15955	open	python-dev, 2019-09-11 14:00

Messages (4)
msg348161 - (view)	Author: Pierre Chopin (pchopin) *	Date: 2019-07-19 09:50
the imghdr library only checks for the presence of (b'JFIF', b'Exif') in the header, which is excluding some valid JPEG file. This is an example of not recognised ile
msg348171 - (view)	Author: Krishna Oza (Krishna Oza) *	Date: 2019-07-19 12:19
The documentation at https://docs.python.org/3/library/imghdr.html?highlight=imghdr#module-imghdr says that JPEG files with JPEG data in JFIF or Exif formats are only supported as of now. Pierre Chopin could help with what format of jpeg you have uploaded.
msg348173 - (view)	Author: Krishna Oza (Krishna Oza) *	Date: 2019-07-19 13:04
Victor I have debugged the issue and found that the jpg file shared doesnt have the information in its header to identify the file format of this file. The imghdr module needs file format information in first 32 bytes when the jpg file is read in binary mode. However for the file "e2006bd7-51d7-4554-9738-ea13207fd104.jpg" there is no such information present and hence I would like to suggest that the issue be closed appropriately. P.S. Attaching the dump of file "e2006bd7-51d7-4554-9738-ea13207fd104.jpg" when read in binary mode.
msg348179 - (view)	Author: Pierre Chopin (pchopin) *	Date: 2019-07-19 14:21
This is actually a duplicate of bpo-16512, i am closing this.

History
Date	User	Action	Args
2022-04-11 14:59:18	admin	set	github: 81810
2019-09-11 14:00:27	python-dev	set	pull_requests: + pull_request15590
2019-07-19 14:21:41	pchopin	set	status: open -> closed resolution: duplicate messages: + msg348179 stage: resolved
2019-07-19 13:04:46	Krishna Oza	set	files: + cpython_imghdr_issue.txt nosy: + vstinner messages: + msg348173
2019-07-19 12:47:19	Krishna Oza	set	type: behavior components: + Library (Lib)
2019-07-19 12:19:02	Krishna Oza	set	nosy: + Krishna Oza messages: + msg348171
2019-07-19 09:50:28	pchopin	create