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Nom-Exif

nom-exif workflow

Exif/metadata parsing library written in pure Rust with nom.

Supported File Types

• Images
  • JPEG
  • HEIF/HEIC
• Videos
  • MOV
  • MP4

Features

Zero-copy when appropriate

Use borrowing and slicing instead of copying whenever possible.

Minimize I/O operations

When metadata is stored at the end of a larger file (such as a MOV file), Seek rather than Read to quickly locate the location of the metadata.

Pay as you go

When extracting Exif data, only the information corresponding to the specified Exif tags are parsed to reduce the overhead when processing a large number of files.

Usage

Parse Exif from Images

use nom_exif::*;
use nom_exif::ExifTag::*;

use std::fs::File;
use std::path::Path;
use std::collections::HashMap;

let f = File::open(Path::new("./testdata/exif.jpg")).unwrap();
let exif = parse_jpeg_exif(f).unwrap().unwrap();

assert_eq!(
    exif.get_value(&ImageWidth).unwrap(),
    Some(IfdEntryValue::U32(3072)));

assert_eq!(
    exif.get_values(&[CreateDate, ModifyDate, DateTimeOriginal]),
    [
        (&CreateDate, "2023:07:09 20:36:33"),
        (&ModifyDate, "2023:07:09 20:36:33"),
        (&DateTimeOriginal, "2023:07:09 20:36:33"),
    ]
    .into_iter()
    .map(|x| (x.0, x.1.into()))
    .collect::<HashMap<_, _>>()
);

Parse metadata from Videos

use nom_exif::*;

use std::fs::File;
use std::path::Path;

let f = File::open(Path::new("./testdata/meta.mov")).unwrap();
let entries = parse_mov_metadata(reader).unwrap();

assert_eq!(
    entries
        .iter()
        .map(|x| format!("{x:?}"))
        .collect::<Vec<_>>()
        .join("\n"),
    r#"("com.apple.quicktime.make", Text("Apple"))
("com.apple.quicktime.model", Text("iPhone X"))
("com.apple.quicktime.software", Text("12.1.2"))
("com.apple.quicktime.location.ISO6709", Text("+27.1281+100.2508+000.000/"))
("com.apple.quicktime.creationdate", Text("2019-02-12T15:27:12+08:00"))"#
);