Locating the EXIF IFD in Canon cr3 files

[Skids]

I apologise if this has been answered elsewhere but all my search attempts end in an error page.

I have been using Exidtool to help me write my own metadata reader for a few specific tags in RW2, ORF and DNG files.  Recently I borrowed a Canon R6 which generates cr3 files.  These do not follow the Tiff file format although they do include IFDs.  For example Exiftool shows that the Tiff like header starts at byte 320 decimal.  In the few other raw files I have looked at the EXIF IFD is pointed with Tag ExifOffset or a second IFD is pointed from the first IFD but this is not the case with the Canon file.  I wonder if there is a pointer somewhere in the file or if the only way of locating the EXIF IFD is by a brute force search for the Tiff header 4949.....?

best wishes

Simon

[Phil Harvey]

Hi Simon,

These files are QuickTime format (like MP4 and HEIF).  Parsing the QuickTime information will allow you to locate the EXIF.

- Phil