Meaning of 'offset' returned by imageinfo

What does the parameter 'offset' returned by imageinfo.m mean? There is no explanation for it in the function documentation.
E.g.:

 Accepted Answer

DGM
DGM on 11 Jul 2022
Edited: DGM on 11 Jul 2022
imageinfo() is just a convenience tool for what imfinfo provides. That said, the metadata that's available depends on the file format and the software that wrote the file, so even the documentation for imfinfo() can't account for every possible tag that might show up. Offset information is common in metadata. Sometimes it's spatial offsets in the image space. Sometimes it's data offsets to the beginning of a certain field or data block.
In this case, I'm going to guess that this is a TIFF file and the tag specifies the byte offset to the end of this image block. I'm not really sure whether that's from the beginning of the file or if it's relative to the IFD position. I'm not terribly familiar with the format specification for TIFF. A more precise (and certain) description would require more information about the file and perhaps some time reading the format spec.

2 Comments

Thanks for your answer. Yes, the file type is a tiff image. Why does it need a byte offset? Just for reference, here is the rest of the output from imageinfo:
Like I mentioned, I'm no expert on the format details, so forgive me if my explanation isn't detailed and precise. A TIFF file is a container and may contain multiple images (and other blocks of information). Offset information would be used by the decoder to navigate within the file.

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R2021b

Asked:

AB
on 11 Jul 2022

Commented:

DGM
on 12 Jul 2022

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