I have been attempting to modify the metadata dates in mp4 files using exiftool. So far, I have only been able to modify the “Date” and “Media created” fields as seen in Windows file explorer. However, when I use Photoshop Elements to organize my pictures and videos, it appears to only recognize the “Date Created” and “Date Modified” fields. Unfortunately, my attempts to modify these fields using the “exiftool “-modifydate” command have been unsuccessful.
After receiving some helpful replies from others, I now understand that Photoshop reads the system dates (Date, amended date, created date), which is why exiftool is unable to modify them. I have found a free tool called Bulk File Changer, which allows me to modify the Created, Modified, and Access dates.
This tool also has an option to read the date from the file names, which works well for me since all my file names begin with the date and time of the original creation. I still need to figure out the UTC issue, but since I live in the UK, the time difference from UTC is not significant for organizing family pictures and videos.
2 Answers
Introduction
Metadata is an essential part of digital files, including images and videos, as it provides information about the file’s content, creation date, and other relevant details. Exiftool is a powerful command-line tool used to read, write, and modify metadata in various file formats, including MP4 files. However, changing metadata dates in MP4 files using Exiftool can be challenging, as some fields appear to resist all attempts to modify them. In this blog post, we will explore how to change metadata dates in MP4 files using Exiftool effectively.
What is Exiftool?
Exiftool is a command-line tool used to read, write, and modify metadata in various file formats, including images, videos, audio files, and documents. It was developed by Phil Harvey and is available for free on his website. Exiftool supports a wide range of metadata formats, including Exif, IPTC, XMP, and many others.
Exiftool is a powerful tool that can be used to extract metadata information from files, modify existing metadata, and write new metadata to files. It can be used to modify metadata dates in MP4 files, including the creation date, modification date, and other relevant dates.
Changing Metadata Dates in MP4 Files using Exiftool
To change metadata dates in MP4 files using Exiftool, you need to open a command prompt or terminal window and navigate to the directory where the MP4 files are located. Once you are in the directory, you can use the following command to modify the creation date of an MP4 file:
exiftool -CreateDate="2021:01:01 00:00:00" file.mp4
This command will change the creation date of the MP4 file to January 1st, 2021, at 12:00:00 AM. You can modify the date and time values to match your requirements.
Similarly, you can use the following command to modify the modification date of an MP4 file:
exiftool -ModifyDate="2021:01:01 00:00:00" file.mp4
This command will change the modification date of the MP4 file to January 1st, 2021, at 12:00:00 AM. Again, you can modify the date and time values to match your requirements.
Why Some Fields Resist Modification
As mentioned earlier, some fields in MP4 files resist modification using Exiftool. This is because these fields are read-only and cannot be modified using Exiftool. Some of these fields include the “Date Created” and “Date Modified” fields, which are used by some applications, such as Photoshop Elements, to organize files.
Instead of modifying these read-only fields, you can modify other metadata fields, such as the creation date and modification date, which can also be used to organize files. Alternatively, you can use other tools, such as Bulk File Changer, to modify the read-only fields.
Using Bulk File Changer to Modify Metadata Dates
Bulk File Changer is a free tool that allows you to modify the creation date, modification date, and access date of multiple files at once. It also allows you to read the required date from the individual file names, which is useful if your file names start with the date and time of original creation.
To use Bulk File Changer, you need to download and install it on your computer. Once installed, you can open it and select the files you want to modify. You can then modify the creation date, modification date, and access date fields using the tool’s interface.
Bulk File Changer also supports the UTC time zone, which is useful if you need to modify metadata dates for files located in different time zones.
Conclusion
Metadata is an essential part of digital files, including images and videos, as it provides information about the file’s content, creation date, and other relevant details. Exiftool is a powerful tool that can be used to read, write, and modify metadata in various file formats, including MP4 files. Changing metadata dates in MP4 files using Exiftool can be challenging, but it is possible by modifying the creation date and modification date fields. Alternatively, you can use other tools, such as Bulk File Changer, to modify the read-only fields.
This text is a combination of exiftool FAQs #2 & #3. It appears that you are attempting to modify the “Date” tag, but this is not the actual tag name that Windows reads. Additionally, Photoshop Elements may be reading a different tag altogether. To complicate matters further, it seems that Windows and Photoshop Elements read timestamps differently.
To view all the timestamps for a file, you can run the following command: exiftool -time:all -G1 -a -s File.mp4. This will display the actual tag names, as well as any duplicate tags and their respective groups.
The three tags that you are most likely interested in modifying are the FileModifyDate, FileCreateDate (both system tags that are part of the underlying file system), and the Quicktime:CreateDate tag. To modify these tags, you can use the following command: exiftool -FileCreateDate=”2019:07:22 12:00:00″ -FileModifyDate=”2019:07:22 12:00:00″ -Quicktime:CreateDate=”2019:07:22 12:00:00″ FILE.mp4.
However, there is a second issue to consider. According to the specification, the Quicktime:CreateDate tag should be in UTC. Windows understands this and displays the time correctly adjusted to the local time zone. However, Adobe programs do not read it properly and assume that the time is in local time, not UTC. Therefore, if the timestamp is written according to the specification, Photoshop Elements may not display the correct time.
The above command will write the Quicktime:CreateDate value exactly as written. If you want to write the value according to the specification (adjusted to UTC), you can add -api QuickTimeUTC to the command and exiftool will adjust the time to UTC based on the local computer’s time setting. Alternatively, if you include the time zone in the value written, e.g. -Quicktime:CreateDate=”2019:07:22 12:00:00-05:00″, then exiftool will use that to adjust to UTC. In the example given, exiftool will set the time to 2019:07:22 17:00:00.
Windows will then read it as 2019:07:22 12:00:00 (assuming your time zone is EDT, -05:00) and Photoshop Elements will read it as 2019:07:22 17:00:00.