Fujifilm Maker Note Parsing Help?

[jahamed]

Kind of new to this... but is there any resource on how to use this to parse Fujifilm image information? It seems all the film simulation/recipe information is tied up in the MakerNote.

For example if I want to get the Film Sim that is under:
FilmMode?: string;
/** ☆☆☆☆ ✔ Example: "NEGATIVE(MONO) " */

How do I know what the possible options are? Is that listed anywhere? Apologies if this is a dumb question. Or is there any other library or function that parses makernote tags by vendor? (fuji, canon, ricoh, etc.)

[mceachen]

Howdy!

Although this library does a bunch with date, time, zone and location parsing, everything else comes from exiftool. Their docs may elaborate on the semantics around a given tag, but know that camera manufacturers are terribly inconsistent with all of this: if you have two Fuji cameras, verify that what you’re looking for is actually encoded the same way in both your cameras.

Here’s their site to start your research:

https://exiftool.org/TagNames/index.html

(also, I’m not aware of a makernote-specific parser.)

Please share if you find anything interesting!

[jahamed]

A real shame there is no makernote parser :(
I found this example from Sam : https://github.com/sambecker/exif-photo-blog/blob/main/src/vendors/fujifilm/index.ts

But it doesn't extract all maker note tags, I'm getting a bit stuck on this part:

const parseFujifilmMakerNote = (
  bytes: Buffer,
  valueForTagUInt: (tagId: number, value: number) => void,
) => {
  const tagCount = bytes.readUint16LE(BYTE_INDEX_TAG_COUNT);
  for (let i = 0; i < tagCount; i++) {
    const index = BYTE_INDEX_FIRST_TAG + i * BYTES_PER_TAG;
    if (index + BYTES_PER_TAG < bytes.length) {
      const tagId = bytes.readUInt16LE(index);
      const tagType = bytes.readUInt16LE(index + BYTE_OFFSET_TAG_TYPE);
      switch (tagType) {
      // UInt16
      case 3:
        valueForTagUInt(
          tagId,
          bytes.readUInt16LE(index + BYTE_OFFSET_TAG_VALUE),
        );
        break;
      // UInt32
      case 4:
        valueForTagUInt(
          tagId,
          bytes.readUInt32LE(index + BYTE_OFFSET_TAG_VALUE),
        );
        break;
      }
    }
  }
};

His code works for unsigned Int16 and UInt32 but doesn't work for signed, not sure if I'm doing something wrong haha

[mceachen]

Oh, just to clarify, exiftool i had a ton of code to pick out makernote stuff, and this library leverages that work. It’s just that there’s always more stuff to decode—it’s a big reason why there are so many incremental releases of exiftool: the author is continuously improving what bits get parsed out.

[jahamed]

Oh, just to clarify, exiftool i had a ton of code to pick out makernote stuff, and this library leverages that work. It’s just that there’s always more stuff to decode—it’s a big reason why there are so many incremental releases of exiftool: the author is continuously improving what bits get parsed out.

I can imagine as new cameras and stuff get released things change around. Oh man I might just end up using this wrapper around exiftool and running an express/node backend just to do exif parsing 😅, was hoping to do it client side but the library is working great at parsing Makernote tags. Thanks for all the work & docs!