Add support for VTF

README.md

@@ -30,6 +30,7 @@ imagesize = "0.12"
 * QOI
 * TGA
 * TIFF
+* VTF
 * WEBP
 
 If you have a format you think should be added, feel free to create an issue.

src/formats/mod.rs

@@ -16,6 +16,7 @@ pub mod psd;
 pub mod qoi;
 pub mod tga;
 pub mod tiff;
+pub mod vtf;
 pub mod webp;
 
 use crate::{ImageError, ImageResult, ImageType};
@@ -106,6 +107,10 @@ pub fn image_type<R: BufRead + Seek>(reader: &mut R) -> ImageResult<ImageType> {
         return Ok(ImageType::Farbfeld);
     }
 
+    if vtf::matches(&header) {
+        return Ok(ImageType::Vtf);
+    }
+
     // Keep TGA last because it has the highest probability of false positives
     if tga::matches(&header, reader) {
         return Ok(ImageType::Tga);

src/formats/vtf.rs

@@ -0,0 +1,17 @@
+use crate::util::*;
+use crate::{ImageResult, ImageSize};
+
+use std::io::{BufRead, Seek, SeekFrom};
+
+pub fn size<R: BufRead + Seek>(reader: &mut R) -> ImageResult<ImageSize> {
+    reader.seek(SeekFrom::Start(16))?;
+
+    Ok(ImageSize {
+        width: read_u16(reader, &Endian::Little)? as usize,
+        height: read_u16(reader, &Endian::Little)? as usize,
+    })
+}
+
+pub fn matches(header: &[u8]) -> bool {
+    header.starts_with(b"VTF\0")
+}

src/lib.rs

@@ -62,6 +62,7 @@ pub enum ImageType {
     Qoi,
     Tga,
     Tiff,
+    Vtf,
     Webp,
 }
 
@@ -239,6 +240,7 @@ fn dispatch_header<R: BufRead + Seek>(reader: &mut R) -> ImageResult<ImageSize>
         ImageType::Qoi => qoi::size(reader),
         ImageType::Tga => tga::size(reader),
         ImageType::Tiff => tiff::size(reader),
+        ImageType::Vtf => vtf::size(reader),
         ImageType::Webp => webp::size(reader),
     }
 }

tests/vtf.rs

@@ -0,0 +1,8 @@
+#[cfg(test)]
+use imagesize::{size, ImageSize};
+
+#[test]
+fn vtf_test() {
+    let dim = size("tests/images/vtf/test.vtf").unwrap();
+    assert_eq!(dim, ImageSize { width: 512, height: 256 });
+}