Tags of type Short are read as Unsigned
lgpasquale opened this issue · comments
When reading a tag that fits into the offset field and is of type SHORT (Tiff type 3) the value is returned as Value::Unsigned instead of Value::Short.
I believe the issue lies in line 407 of ifd.rs.
The right behavior is what can be seen when multiple values are handled (line 475 of ifd.rs)
This makes sense to fix, though the annoying part is figuring out whether anywhere else in the code is relying on the current behavior. Or whether it is likely to break any downstream users and thus might warrant additional caution
It looks like a minimal fix is something like so.
This will make all the tests run successfully.
Regarding side effects I would suppose anyone interfering with the TAG data directly might have colliding types. What use case brought you to this, @lgpasquale ?
I suppose taking care of SSHORT is needed as well? This would require introducing an additional Value:
pub enum Value {
Byte(u8),
Short(u16),
Signed(i32),
SignedBig(i64),
Unsigned(u32),
UnsignedBig(u64),
Float(f32),
Double(f64),
List(Vec<Value>),
Rational(u32, u32),
RationalBig(u64, u64),
SRational(i32, i32),
SRationalBig(i64, i64),
Ascii(String),
Ifd(u32),
IfdBig(u64),
}