Add support for 'target_size' parameter

tests/test_webp.py

@@ -148,6 +148,16 @@ def test_image_simple(self):
             expected = np.asarray(img, dtype=np.uint8)
             assert_array_equal(actual, expected)
 
+    def test_image_target_size(self):
+        rng = np.random.RandomState(42)
+        img = Image.fromarray(rng.randint(0, 256, size=(128, 128, 3), dtype=np.uint8))
+
+        with TemporaryDirectory() as tmpdir:
+            file_name = os.path.join(tmpdir, 'image.webp')
+
+            webp.save_image(img, file_name, target_size=5000, passes=6)
+            assert os.path.getsize(file_name) <= 5000
+
     def test_image_palette(self, image_bars_palette):
         with TemporaryDirectory() as tmpdir:
             file_name = os.path.join(tmpdir, 'image.webp')

tests/test_webp_config.py

@@ -11,6 +11,11 @@ def test_default(self):
         assert config.method == 4
         del config
 
+    def test_default_target_size_override(self):
+        config = webp.WebPConfig.new(target_size=1000)
+        assert config.target_size == 1000
+        del config
+
     def test_default_lossless(self):
         config = webp.WebPConfig.new(lossless=True)
         assert config.lossless is True

webp/__init__.py

@@ -66,6 +66,22 @@ def method(self) -> int:
     def method(self, method: int) -> None:
         self.ptr.method = method
 
+    @property
+    def target_size(self) -> int:
+        return self.ptr.target_size
+
+    @target_size.setter
+    def target_size(self, target_size: int) -> None:
+        self.ptr.target_size = target_size
+
+    @property
+    def passes(self) -> int:
+        return getattr(self.ptr, "pass")
+
+    @passes.setter
+    def passes(self, passes: int) -> None:
+        setattr(self.ptr, "pass", passes)
+
     def validate(self) -> bool:
         return lib.WebPValidateConfig(self.ptr) != 0
 
@@ -74,7 +90,10 @@ def new(preset: WebPPreset = WebPPreset.DEFAULT,
             quality: Optional[float] = None,
             lossless: bool = False,
             lossless_preset: Optional[int] = None,
-            method: Optional[int] = None) -> "WebPConfig":
+            method: Optional[int] = None,
+            *,
+            target_size: Optional[int] = None,
+            passes: Optional[int] = None) -> "WebPConfig":
         """Create a new WebPConfig instance to describe encoder settings.
 
         1. The preset is loaded, setting default values for quality factor (75.0) and compression
@@ -98,6 +117,9 @@ def new(preset: WebPPreset = WebPPreset.DEFAULT,
                 factor and compression method together. Effective default is 6.
             method (int, optional): Compression method (0=fast but big, 6=small but slow).
                 Overrides presets. Effective default is 4.
+            target_size (int, optional): Desired target size in bytes. When setting this, you
+                will likely want to set passes to a value greater than 1 also.
+            passes (int, optional): Number of entropy-analysis passes (between 1 and 10 inclusive).
 
         Returns:
             WebPConfig: The new WebPConfig instance.
@@ -120,6 +142,10 @@ def new(preset: WebPPreset = WebPPreset.DEFAULT,
             config.quality = quality
         if method is not None:
             config.method = method
+        if target_size is not None:
+            config.target_size = target_size
+        if passes is not None:
+            config.passes = passes
 
         if not config.validate():
             raise WebPError('config is not valid')

webp_build/cdef.h

@@ -7,6 +7,14 @@ typedef enum WebPPreset {
   WEBP_PRESET_TEXT
 } WebPPreset;
 
+typedef enum WebPImageHint {
+  WEBP_HINT_DEFAULT = 0,
+  WEBP_HINT_PICTURE,
+  WEBP_HINT_PHOTO,
+  WEBP_HINT_GRAPH,
+  WEBP_HINT_LAST
+} WebPImageHint;
+
 typedef enum WEBP_CSP_MODE {
   MODE_RGB = 0, MODE_RGBA = 1,
   MODE_BGR = 2, MODE_BGRA = 3,
@@ -110,6 +118,19 @@ struct WebPConfig {
   int lossless;
   float quality;
   int method;
+  WebPImageHint image_hint;
+  int target_size;
+  float target_PSNR;
+  int segments;
+  int sns_strength;
+  int filter_strength;
+  int filter_sharpness;
+  int filter_type;
+  int autofilter;
+  int alpha_compression;
+  int alpha_filtering;
+  int alpha_quality;
+  int pass;
   ...;
 };
 typedef struct WebPConfig WebPConfig;