Add horizontal predictor support (#240)

tests/predict.rs

@@ -0,0 +1,231 @@
+extern crate tiff;
+
+use tiff::decoder::{Decoder, DecodingResult};
+use tiff::encoder::{colortype, Compression, Predictor, TiffEncoder};
+use tiff::ColorType;
+
+use std::fs::File;
+use std::io::{Cursor, Seek, SeekFrom};
+use std::path::PathBuf;
+
+const TEST_IMAGE_DIR: &str = "./tests/images/";
+
+macro_rules! test_predict {
+    ($name:ident, $buffer:ident, $buffer_ty:ty) => {
+        fn $name<C: colortype::ColorType<Inner = $buffer_ty>>(
+            file: &str,
+            expected_type: ColorType,
+        ) {
+            let path = PathBuf::from(TEST_IMAGE_DIR).join(file);
+            let file = File::open(path).expect("Cannot find test image!");
+            let mut decoder = Decoder::new(file).expect("Cannot create decoder!");
+
+            assert_eq!(decoder.colortype().unwrap(), expected_type);
+            let image_data = match decoder.read_image().unwrap() {
+                DecodingResult::$buffer(res) => res,
+                _ => panic!("Wrong data type"),
+            };
+
+            let mut predicted = Vec::with_capacity(image_data.len());
+            C::horizontal_predict(&image_data, &mut predicted);
+
+            let sample_size = C::SAMPLE_FORMAT.len();
+
+            (0..sample_size).for_each(|i| {
+                assert_eq!(predicted[i], image_data[i]);
+            });
+
+            (sample_size..image_data.len()).for_each(|i| {
+                predicted[i] = predicted[i].wrapping_add(predicted[i - sample_size]);
+                assert_eq!(predicted[i], image_data[i]);
+            });
+        }
+    };
+}
+
+test_predict!(test_u8_predict, U8, u8);
+test_predict!(test_i8_predict, I8, i8);
+test_predict!(test_u16_predict, U16, u16);
+test_predict!(test_i16_predict, I16, i16);
+test_predict!(test_u32_predict, U32, u32);
+test_predict!(test_u64_predict, U64, u64);
+
+#[test]
+fn test_gray_u8_predict() {
+    test_u8_predict::<colortype::Gray8>("minisblack-1c-8b.tiff", ColorType::Gray(8));
+}
+
+#[test]
+fn test_gray_i8_predict() {
+    test_i8_predict::<colortype::GrayI8>("minisblack-1c-i8b.tiff", ColorType::Gray(8));
+}
+
+#[test]
+fn test_rgb_u8_predict() {
+    test_u8_predict::<colortype::RGB8>("rgb-3c-8b.tiff", ColorType::RGB(8));
+}
+
+#[test]
+fn test_cmyk_u8_predict() {
+    test_u8_predict::<colortype::CMYK8>("cmyk-3c-8b.tiff", ColorType::CMYK(8));
+}
+
+#[test]
+fn test_gray_u16_predict() {
+    test_u16_predict::<colortype::Gray16>("minisblack-1c-16b.tiff", ColorType::Gray(16));
+}
+
+#[test]
+fn test_gray_i16_predict() {
+    test_i16_predict::<colortype::GrayI16>("minisblack-1c-i16b.tiff", ColorType::Gray(16));
+}
+
+#[test]
+fn test_rgb_u16_predict() {
+    test_u16_predict::<colortype::RGB16>("rgb-3c-16b.tiff", ColorType::RGB(16));
+}
+
+#[test]
+fn test_cmyk_u16_predict() {
+    test_u16_predict::<colortype::CMYK16>("cmyk-3c-16b.tiff", ColorType::CMYK(16));
+}
+
+#[test]
+fn test_gray_u32_predict() {
+    test_u32_predict::<colortype::Gray32>("gradient-1c-32b.tiff", ColorType::Gray(32));
+}
+
+#[test]
+fn test_rgb_u32_predict() {
+    test_u32_predict::<colortype::RGB32>("gradient-3c-32b.tiff", ColorType::RGB(32));
+}
+
+#[test]
+fn test_gray_u64_predict() {
+    test_u64_predict::<colortype::Gray64>("gradient-1c-64b.tiff", ColorType::Gray(64));
+}
+
+#[test]
+fn test_rgb_u64_predict() {
+    test_u64_predict::<colortype::RGB64>("gradient-3c-64b.tiff", ColorType::RGB(64));
+}
+
+#[test]
+fn test_ycbcr_u8_predict() {
+    test_u8_predict::<colortype::YCbCr8>("tiled-jpeg-ycbcr.tif", ColorType::YCbCr(8));
+}
+
+macro_rules! test_predict_roundtrip {
+    ($name:ident, $buffer:ident, $buffer_ty:ty) => {
+        fn $name<C: colortype::ColorType<Inner = $buffer_ty>>(
+            file: &str,
+            expected_type: ColorType,
+        ) {
+            let path = PathBuf::from(TEST_IMAGE_DIR).join(file);
+            let img_file = File::open(path).expect("Cannot find test image!");
+            let mut decoder = Decoder::new(img_file).expect("Cannot create decoder");
+            assert_eq!(decoder.colortype().unwrap(), expected_type);
+
+            let image_data = match decoder.read_image().unwrap() {
+                DecodingResult::$buffer(res) => res,
+                _ => panic!("Wrong data type"),
+            };
+
+            let mut file = Cursor::new(Vec::new());
+            {
+                let mut tiff = TiffEncoder::new(&mut file)
+                    .unwrap()
+                    .with_predictor(Predictor::Horizontal);
+
+                let (width, height) = decoder.dimensions().unwrap();
+                tiff.write_image::<C>(width, height, &image_data).unwrap();
+            }
+            file.seek(SeekFrom::Start(0)).unwrap();
+            {
+                let mut decoder = Decoder::new(&mut file).unwrap();
+                if let DecodingResult::$buffer(img_res) =
+                    decoder.read_image().expect("Decoding image failed")
+                {
+                    assert_eq!(image_data, img_res);
+                } else {
+                    panic!("Wrong data type");
+                }
+            }
+        }
+    };
+}
+
+test_predict_roundtrip!(test_u8_predict_roundtrip, U8, u8);
+test_predict_roundtrip!(test_i8_predict_roundtrip, I8, i8);
+test_predict_roundtrip!(test_u16_predict_roundtrip, U16, u16);
+test_predict_roundtrip!(test_i16_predict_roundtrip, I16, i16);
+test_predict_roundtrip!(test_u32_predict_roundtrip, U32, u32);
+test_predict_roundtrip!(test_u64_predict_roundtrip, U64, u64);
+
+#[test]
+fn test_gray_u8_predict_roundtrip() {
+    test_u8_predict_roundtrip::<colortype::Gray8>("minisblack-1c-8b.tiff", ColorType::Gray(8));
+}
+
+#[test]
+fn test_gray_i8_predict_roundtrip() {
+    test_i8_predict_roundtrip::<colortype::GrayI8>("minisblack-1c-i8b.tiff", ColorType::Gray(8));
+}
+
+#[test]
+fn test_rgb_u8_predict_roundtrip() {
+    test_u8_predict_roundtrip::<colortype::RGB8>("rgb-3c-8b.tiff", ColorType::RGB(8));
+}
+
+#[test]
+fn test_cmyk_u8_predict_roundtrip() {
+    test_u8_predict_roundtrip::<colortype::CMYK8>("cmyk-3c-8b.tiff", ColorType::CMYK(8));
+}
+
+#[test]
+fn test_gray_u16_predict_roundtrip() {
+    test_u16_predict_roundtrip::<colortype::Gray16>("minisblack-1c-16b.tiff", ColorType::Gray(16));
+}
+
+#[test]
+fn test_gray_i16_predict_roundtrip() {
+    test_i16_predict_roundtrip::<colortype::GrayI16>(
+        "minisblack-1c-i16b.tiff",
+        ColorType::Gray(16),
+    );
+}
+
+#[test]
+fn test_rgb_u16_predict_roundtrip() {
+    test_u16_predict_roundtrip::<colortype::RGB16>("rgb-3c-16b.tiff", ColorType::RGB(16));
+}
+
+#[test]
+fn test_cmyk_u16_predict_roundtrip() {
+    test_u16_predict_roundtrip::<colortype::CMYK16>("cmyk-3c-16b.tiff", ColorType::CMYK(16));
+}
+
+#[test]
+fn test_gray_u32_predict_roundtrip() {
+    test_u32_predict_roundtrip::<colortype::Gray32>("gradient-1c-32b.tiff", ColorType::Gray(32));
+}
+
+#[test]
+fn test_rgb_u32_predict_roundtrip() {
+    test_u32_predict_roundtrip::<colortype::RGB32>("gradient-3c-32b.tiff", ColorType::RGB(32));
+}
+
+#[test]
+fn test_gray_u64_predict_roundtrip() {
+    test_u64_predict_roundtrip::<colortype::Gray64>("gradient-1c-64b.tiff", ColorType::Gray(64));
+}
+
+#[test]
+fn test_rgb_u64_predict_roundtrip() {
+    test_u64_predict_roundtrip::<colortype::RGB64>("gradient-3c-64b.tiff", ColorType::RGB(64));
+}
+
+#[test]
+fn test_ycbcr_u8_predict_roundtrip() {
+    test_u8_predict_roundtrip::<colortype::YCbCr8>("tiled-jpeg-ycbcr.tif", ColorType::YCbCr(8));
+}