Createdate for Dropbox photos

[exifzarko]

Hello!

I have tried changing the EXIF data for one of my photos, but it still does not get displayed in the correct timeline in Dropbox. I must be doing something wrong or there is a trick on how to make Dropbox display the photos the right way. As you can see, I have changed the createdate properties, but Dropbox still displays the photo as "Missing dates" :-(

ExifTool Version Number         : 10.40
File Name                       : Zarko photopoint_photo.png
Directory                       : E:/Users/Owner/Desktop/exiftool-10.40
File Size                       : 2.8 MB
File Modification Date/Time     : 2017:01:16 11:29:26+01:00
File Access Date/Time           : 2017:01:16 11:29:26+01:00
File Creation Date/Time         : 2017:01:16 10:56:44+01:00
File Permissions                : rw-rw-rw-
File Type                       : PNG
File Type Extension             : png
MIME Type                       : image/png
Image Width                     : 2560
Image Height                    : 1704
Bit Depth                       : 8
Color Type                      : RGB with Alpha
Compression                     : Deflate/Inflate
Filter                          : Adaptive
Interlace                       : Noninterlaced
Background Color                : 255 255 255
Create Date                     : 2017:01:12 14:05:56
XMP Toolkit                     : Image::ExifTool 10.40
Image Size                      : 2560x1704
Megapixels                      : 4.4
-- press RETURN --

I kindly ask if you could write me a command that works. I am clueless.

Thanks in advance!

BR,

Zarko.

[exifzarko]

...I think I know the cause of the problem but I do not know the solution....The cause is most probably the so-called "Apple createdate", which Dropbox uses for displaying in a timeline.

[Phil Harvey]

For your example, you might add -G1 to the command so you can see where the tags are stored.

PNG may a bit problematic because there isn't very good support for PNG metadata in the wild.

I don't know what you mean by "Apple createdate".  The CreateDate in your file is likely native PNG metadata (but you will see for sure with the -G1 option).

- Phil

[exifzarko]

Thanks Phil, but it did not work. I got this:

E:\Users\Owner\Desktop\exiftool-10.40>exiftool *.png -G1
[ExifTool]      ExifTool Version Number         : 10.40
[System]        File Name                       : Zarko photopoint_photo.png
[System]        Directory                       : .
[System]        File Size                       : 2.8 MB
[System]        File Modification Date/Time     : 2017:01:16 13:57:06+01:00
[System]        File Access Date/Time           : 2017:01:16 13:57:06+01:00
[System]        File Creation Date/Time         : 2017:01:16 10:56:44+01:00
[System]        File Permissions                : rw-rw-rw-
[File]          File Type                       : PNG
[File]          File Type Extension             : png
[File]          MIME Type                       : image/png
[PNG]           Image Width                     : 2560
[PNG]           Image Height                    : 1704
[PNG]           Bit Depth                       : 8
[PNG]           Color Type                      : RGB with Alpha
[PNG]           Compression                     : Deflate/Inflate
[PNG]           Filter                          : Adaptive
[PNG]           Interlace                       : Noninterlaced
[PNG]           Background Color                : 255 255 255
[PNG]           Create Date                     : 2017:01:12 14:05:56
[XMP-x]         XMP Toolkit                     : Image::ExifTool 10.40
[Composite]     Image Size                      : 2560x1704
[Composite]     Megapixels                      : 4.4

E:\Users\Owner\Desktop\exiftool-10.40>exiftool -createdate="2017:01:12 14:05:56" *.png -G1
    1 image files updated

The photo is still not displayed with the correct date. Dropbox reads it as a photo with a "missing date". What I meant by Apple createdate is the quicktime format, which might work. I have just checked one of my other photos and that one has two createdate fields. So, I am probably missing the other one, but I do not know how to format the file. I have tried with the simple command: exiftool -createdate="2017:01:12 14:05:56" *.png as well as with this: exiftool -api quicktimeutc=1 -quicktime:createdate="2017:01:12 14:05:56+01:00" -ext png .

Have I missed something or it is impossible to add more "createdate" fields to my png photo?

[Phil Harvey]

With ExifTool, you may write PNG:CreateDate, XMP:CreateDate and EXIF:CreateDate to PNG images (of these, PNG:CreateDate is most likely to be supported by other software, and EXIF:CreateDate is the least).  QuickTime:CreateDate is only for QuickTime-format files.

- Phil

[exifzarko]

I have now tried all three commands as well as converting the PNG file to JPG. The result is discouraging :-( I could not believe that such a simple task is so complicating. Herewith attached both of my files (PNG and JPG), both showing missing dates in Dropbox Photos :-(

Could you please think of something else that might work?

[Phil Harvey]

You need to figure out what information dropbox uses (if any), and I can't help with this.

Perhaps you could ask this question in a dropbox forum (if such a thing exists).

- Phil

[exifzarko]

Thanks - I have done that now.

I guess the problem is the PNG extension, which does not work well with metadata. Can Exiftool remove all metadata from a PNG file?

[Phil Harvey]

Can Exiftool remove all metadata from a PNG file?

Yes:  exiftool -all= image.png

- Phil

[StarGeek]

If you're getting a PNG file to show up at all in your dropbox photo timeline, you're doing that I can't reproduce.  I've tried multiple PNG files now, with a lot of metadata and without any metadata, and not one will show up in my Dropbox photo timeline.

Jpgs show up pretty quickly and I'm going to check to see what time tags they prioritize, but nothing at all with PNGs.

[StarGeek]

Dropbox's photo timeline only looks at two timestamps, EXIF:DateTimeOriginal and EXIF:ModifyDate.  EXIF data is non-standard in PNG images and, as I said, I was unable to get a PNG to show up at all in the timeline.

[exifzarko]

Thanks StarGeek! You are right on the point - Dropbox does not recognise PNG files and therefore the only solution is to convert PNG files to JPG files and then run exiftool with the commands that you figured out work. In my tests sometimes it was enough to use  -DateTimeOriginal and photos will appear in my Dropbox timeline perfectly. Thanks again for the excellent support!