EXIF lossless rotation
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EXIF lossless rotation
Hello,
I did not find this rotation function in XnView.
I think the best way to rotate a JPG picture, is to not rotate the picture (!) but change the orientation EXIF value of the picture.
To change the orientation of the picture taken with my digital camera (which has no orientation sensor), I use EXIF Editor ( http://www.photo-freeware.net/quick-exif-editor.php). Thanks to this page (http://jpegclub.org/exif_orientation.html), I change or add the "orientation" EXIF value to 6 or 8. This way, the picture is not changed (really better for printing), and the picture is correctly displayed in the good renderer like XnView.
It would be great if XnView had this function built-in ("Define picture Orientation" with the "F" pictures in http://jpegclub.org/exif_orientation.html) or a "Rotate with EXIF" that from left to right, change or add the EXIF orientation (6 -> 1 -> 8 -> 3 -> 6 ...).
What do you think of this?
(I looked for this function in XnView and in the suggestion forum and did not find it).
--
Ben
I did not find this rotation function in XnView.
I think the best way to rotate a JPG picture, is to not rotate the picture (!) but change the orientation EXIF value of the picture.
To change the orientation of the picture taken with my digital camera (which has no orientation sensor), I use EXIF Editor ( http://www.photo-freeware.net/quick-exif-editor.php). Thanks to this page (http://jpegclub.org/exif_orientation.html), I change or add the "orientation" EXIF value to 6 or 8. This way, the picture is not changed (really better for printing), and the picture is correctly displayed in the good renderer like XnView.
It would be great if XnView had this function built-in ("Define picture Orientation" with the "F" pictures in http://jpegclub.org/exif_orientation.html) or a "Rotate with EXIF" that from left to right, change or add the EXIF orientation (6 -> 1 -> 8 -> 3 -> 6 ...).
What do you think of this?
(I looked for this function in XnView and in the suggestion forum and did not find it).
--
Ben
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Re: EXIF lossless rotation
Ok, i'll add thatben.che wrote:Hello,
I did not find this rotation function in XnView.
I think the best way to rotate a JPG picture, is to not rotate the picture (!) but change the orientation EXIF value of the picture.
To change the orientation of the picture taken with my digital camera (which has no orientation sensor), I use EXIF Editor ( http://www.photo-freeware.net/quick-exif-editor.php). Thanks to this page (http://jpegclub.org/exif_orientation.html), I change or add the "orientation" EXIF value to 6 or 8. This way, the picture is not changed (really better for printing), and the picture is correctly displayed in the good renderer like XnView.
It would be great if XnView had this function built-in ("Define picture Orientation" with the "F" pictures in http://jpegclub.org/exif_orientation.html) or a "Rotate with EXIF" that from left to right, change or add the EXIF orientation (6 -> 1 -> 8 -> 3 -> 6 ...).
What do you think of this?
(I looked for this function in XnView and in the suggestion forum and did not find it).
Pierre.
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ben.che: I used to change the orientation with stereo photo maker. I don't know your program, but I don't want to test it because I need to install .net framework.
I suggested this feature here:
http://newsgroup.xnview.com/viewtopic.p ... rientation
The other parameters (010e Image description, 8298 Copyright, 9286 Exif user comment) would also be good to be writable.
I'm happy that Pierre now wants to add this.
I suggested this feature here:
http://newsgroup.xnview.com/viewtopic.p ... rientation
The other parameters (010e Image description, 8298 Copyright, 9286 Exif user comment) would also be good to be writable.
I'm happy that Pierre now wants to add this.
XnView 2.04, 2.13 Windows 2000 SP4 and Windows XP SP3 and Windows 7 64bit
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There is a problem with variable length field like copyright or user comment. If i rewrite EXIF, makernotes are deleted. But perhaps not a problem for most users???Anika wrote:ben.che: I used to change the orientation with stereo photo maker. I don't know your program, but I don't want to test it because I need to install .net framework.
I suggested this feature here:
http://newsgroup.xnview.com/viewtopic.p ... rientation
The other parameters (010e Image description, 8298 Copyright, 9286 Exif user comment) would also be good to be writable.
I'm happy that Pierre now wants to add this.
Pierre.
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Wrong rotation display in most viewers
In most Viewers (including Vista Explorer) the orientation of portrait JPEGs is wrong,
only XnView and some other viewers are showing the correct rotation according to the orientation flag.
If I rotate a picture in the new Nikon ViewNX, only the orientation flag is changed (in NEF and also in JPEGs).
This rotated picture is show correct in XnView.
If I recreate the EXIF-Thumbnail in XnView, the orientation is not correct any more (maybe a bug).
I'm not happy with the orientation flag at the moment and would still prefer to rotate the whole picture.
Walter
only XnView and some other viewers are showing the correct rotation according to the orientation flag.
If I rotate a picture in the new Nikon ViewNX, only the orientation flag is changed (in NEF and also in JPEGs).
This rotated picture is show correct in XnView.
If I recreate the EXIF-Thumbnail in XnView, the orientation is not correct any more (maybe a bug).
I'm not happy with the orientation flag at the moment and would still prefer to rotate the whole picture.
Walter
Walter
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I support this feature. However, the displayed value of the Exif orientation flag should always be that which is saved in the file. See also: Once more: EXIF Orientation.
Gnome gThumb has this Exif rotation feature. When selecting the lossless rotation, there is an option "Apply physical transform". If this is not selected, only the Exif orientation tag will be changed.
Gnome gThumb has this Exif rotation feature. When selecting the lossless rotation, there is an option "Apply physical transform". If this is not selected, only the Exif orientation tag will be changed.
-- Karl
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I think there are 3 different cases:
1) Temporary rotate an image for display according to the orientation flag should not change the orientation flag.
2) Permanent rotation of an image with lossless JPEG rotation should reset the orientation flag, so that this image is not again rotated by any viewer.
3) Permanent lossless rotation by just changing the rotation flag, like Nikon ViewNX is doing. Rotating an image like this will not change the JPEG data itself.
I'm not sure, how to correctly handle the embedded thumbnails, and if there is any extra thumbnail rotation flag in EXIF data.
I know many pictures with rotated images but not rotated thumbnails. XnView can recreate the thumbnail so that this error caused by other software is corrected.
But if I recreate in XnView the thumbnail of a picture that is rotated by ViewNX, the orientation of the thumbnail picture is not correct any more.
1) Temporary rotate an image for display according to the orientation flag should not change the orientation flag.
2) Permanent rotation of an image with lossless JPEG rotation should reset the orientation flag, so that this image is not again rotated by any viewer.
3) Permanent lossless rotation by just changing the rotation flag, like Nikon ViewNX is doing. Rotating an image like this will not change the JPEG data itself.
I'm not sure, how to correctly handle the embedded thumbnails, and if there is any extra thumbnail rotation flag in EXIF data.
I know many pictures with rotated images but not rotated thumbnails. XnView can recreate the thumbnail so that this error caused by other software is corrected.
But if I recreate in XnView the thumbnail of a picture that is rotated by ViewNX, the orientation of the thumbnail picture is not correct any more.
Walter
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Ok, so an option will be good to make a JPEG lossless rotation (like now) or to change only the orientation flag in EXIFKarl02 wrote:I support this feature. However, the displayed value of the Exif orientation flag should always be that which is saved in the file. See also: Once more: EXIF Orientation.
Gnome gThumb has this Exif rotation feature. When selecting the lossless rotation, there is an option "Apply physical transform". If this is not selected, only the Exif orientation tag will be changed.
Pierre.
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i have a problem with the picture orientation in thumbnails. i've put an screenshot:

i have also removed in options to automatically rotate the picture, but it is always the same.
this is probably the problem that is been discussed in this topic. will that be fixed?
p.s. simple as can be: thanks for the excellent program!

i have also removed in options to automatically rotate the picture, but it is always the same.
this is probably the problem that is been discussed in this topic. will that be fixed?
p.s. simple as can be: thanks for the excellent program!

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How did you create this picture?
Is it a picture out of the camera,
or did you made any rotations with any software.
There is a lot of software that cannot handle the orientation tag correct.
XnView can handle the tag, but there is a small bug by recreating the thumbnail of a rotated picture.
There are so many different cases to handle, it's amazing.
When you take a picture in portrait format, some cameras can save this in EXIF, some do not.
When you rotate a picture, some software is rotating the JPEG but forgetting to reset the tag,
some software is just changing the tag, some software is forgetting to rotate the thumbnail.
So it's very easy to get inconsistency between the picture and it's thumbnail.
Is it a picture out of the camera,
or did you made any rotations with any software.
There is a lot of software that cannot handle the orientation tag correct.
XnView can handle the tag, but there is a small bug by recreating the thumbnail of a rotated picture.
There are so many different cases to handle, it's amazing.
When you take a picture in portrait format, some cameras can save this in EXIF, some do not.
When you rotate a picture, some software is rotating the JPEG but forgetting to reset the tag,
some software is just changing the tag, some software is forgetting to rotate the thumbnail.
So it's very easy to get inconsistency between the picture and it's thumbnail.
Walter
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Yes, this can happen depending on the process and software used. Background info and some trouble shooting is provided in FAQ 'How to rotate images automatically'.scw2wi wrote:... So it's very easy to get inconsistency between the picture and it's thumbnail.