feat(SaveImageLM): expose webp_method and jpeg_subsampling as conditional node inputs

Add two new optional parameters to the Save Image node:

- webp_method (INT, 0-6, default 6): Controls WebP compression level.
  0=fastest/largest, 6=slowest/smallest. Previously hardcoded to 0.
- jpeg_subsampling (INT, 0-2, default 0): Controls JPEG chroma
  subsampling. 0=4:4:4 (best quality), 1=4:2:2, 2=4:2:0.

Frontend JS extension hides/disables each parameter when the
selected file_format doesn't apply (e.g., webp_method is hidden
when saving as PNG or JPEG). 7 new tests cover parameter plumbing
and default consistency across INPUT_TYPES, save_images(), and
process_image().

py/nodes/save_image.py

@@ -220,6 +220,24 @@ class SaveImageLM:
                         "tooltip": "Compression quality for JPEG and lossy WebP formats (1-100). Higher values mean better quality but larger files.",
                     },
                 ),
+                "webp_method": (
+                    "INT",
+                    {
+                        "default": 6,
+                        "min": 0,
+                        "max": 6,
+                        "tooltip": "WebP compression method (0-6). 0=fastest/largest, 6=slowest/smallest. Only applies when file_format is 'webp'.",
+                    },
+                ),
+                "jpeg_subsampling": (
+                    "INT",
+                    {
+                        "default": 0,
+                        "min": 0,
+                        "max": 2,
+                        "tooltip": "JPEG chroma subsampling level. 0=4:4:4 (best quality), 1=4:2:2, 2=4:2:0 (smallest files). Only applies when file_format is 'jpeg'.",
+                    },
+                ),
                 "embed_workflow": (
                     "BOOLEAN",
                     {
@@ -756,6 +774,8 @@ class SaveImageLM:
         extra_pnginfo=None,
         lossless_webp=True,
         quality=100,
+        webp_method=6,
+        jpeg_subsampling=0,
         embed_workflow=False,
         save_with_metadata=True,
         add_counter_to_filename=True,
@@ -810,15 +830,14 @@ class SaveImageLM:
             elif file_format == "jpeg":
                 file = base_filename + ".jpg"
                 file_extension = ".jpg"
-                save_kwargs = {"quality": quality, "optimize": True}
+                save_kwargs = {"quality": quality, "optimize": True, "subsampling": jpeg_subsampling}
             elif file_format == "webp":
                 file = base_filename + ".webp"
                 file_extension = ".webp"
-                # Add optimization param to control performance
                 save_kwargs = {
                     "quality": quality,
                     "lossless": lossless_webp,
-                    "method": 0,
+                    "method": webp_method,
                 }
             else:
                 raise ValueError(f"Unsupported file format: {file_format}")
@@ -905,6 +924,8 @@ class SaveImageLM:
         extra_pnginfo=None,
         lossless_webp=True,
         quality=100,
+        webp_method=6,
+        jpeg_subsampling=0,
         embed_workflow=False,
         save_with_metadata=True,
         add_counter_to_filename=True,
@@ -934,6 +955,8 @@ class SaveImageLM:
             extra_pnginfo,
             lossless_webp,
             quality,
+            webp_method,
+            jpeg_subsampling,
             embed_workflow,
             save_with_metadata,
             add_counter_to_filename,

tests/nodes/test_save_image.py

@@ -363,3 +363,102 @@ def test_save_image_as_recipe_writes_recipe_without_async_scanner_calls(
     assert recipe["gen_params"] == {"prompt": "prompt text", "seed": 123}
     assert scanner._json_path_map[recipe["id"]] == os.path.normpath(str(recipe_files[0]))
     assert scanner.fts_updates == [(recipe["id"], "add")]
+
+
+# ---------------------------------------------------------------------------
+# Tests for webp_method and jpeg_subsampling parameters
+# ---------------------------------------------------------------------------
+
+def _capture_save_kwargs(monkeypatch):
+    """Monkeypatch Image.Image.save to capture kwargs while still saving to disk."""
+    real_save = Image.Image.save
+    captured_kwargs = {}
+
+    def _fake_save(self, fp, *args, **kwargs):
+        captured_kwargs.update(kwargs)
+        return real_save(self, fp, *args, **kwargs)
+
+    monkeypatch.setattr(Image.Image, "save", _fake_save)
+    return captured_kwargs
+
+
+def test_webp_method_default_passed_to_pillow_save(monkeypatch, tmp_path):
+    _configure_save_paths(monkeypatch, tmp_path)
+    _configure_metadata(monkeypatch, {"prompt": "test", "seed": 1})
+    captured = _capture_save_kwargs(monkeypatch)
+
+    node = SaveImageLM()
+    node.save_images([_make_image()], "ComfyUI", "webp", id="node-1")
+
+    assert "method" in captured
+    assert captured["method"] == 6
+
+
+def test_webp_method_custom_value_passed_to_pillow_save(monkeypatch, tmp_path):
+    _configure_save_paths(monkeypatch, tmp_path)
+    _configure_metadata(monkeypatch, {"prompt": "test", "seed": 1})
+    captured = _capture_save_kwargs(monkeypatch)
+
+    node = SaveImageLM()
+    node.save_images(
+        [_make_image()], "ComfyUI", "webp", id="node-1", webp_method=3
+    )
+
+    assert captured["method"] == 3
+
+
+def test_jpeg_subsampling_default_passed_to_pillow_save(monkeypatch, tmp_path):
+    _configure_save_paths(monkeypatch, tmp_path)
+    _configure_metadata(monkeypatch, {"prompt": "test", "seed": 1})
+    captured = _capture_save_kwargs(monkeypatch)
+
+    node = SaveImageLM()
+    node.save_images([_make_image()], "ComfyUI", "jpeg", id="node-1")
+
+    assert "subsampling" in captured
+    assert captured["subsampling"] == 0
+
+
+def test_jpeg_subsampling_custom_value_passed_to_pillow_save(monkeypatch, tmp_path):
+    _configure_save_paths(monkeypatch, tmp_path)
+    _configure_metadata(monkeypatch, {"prompt": "test", "seed": 1})
+    captured = _capture_save_kwargs(monkeypatch)
+
+    node = SaveImageLM()
+    node.save_images(
+        [_make_image()], "ComfyUI", "jpeg", id="node-1", jpeg_subsampling=1
+    )
+
+    assert captured["subsampling"] == 1
+
+
+class TestParameterDefaultConsistency:
+    """Verify defaults match across INPUT_TYPES, save_images(), and process_image()."""
+
+    def test_webp_method_defaults_are_consistent(self):
+        input_types = SaveImageLM.INPUT_TYPES()
+        optional = input_types["optional"]
+
+        assert optional["webp_method"][1]["default"] == 6
+        assert SaveImageLM.save_images.__defaults__[4] == 6  # positional: webp_method=6 is at index 4
+        assert SaveImageLM.process_image.__defaults__[6] == 6
+
+    def test_jpeg_subsampling_defaults_are_consistent(self):
+        input_types = SaveImageLM.INPUT_TYPES()
+        optional = input_types["optional"]
+
+        assert optional["jpeg_subsampling"][1]["default"] == 0
+        assert SaveImageLM.save_images.__defaults__[5] == 0
+        assert SaveImageLM.process_image.__defaults__[7] == 0
+
+
+def test_png_does_not_pass_webp_method_or_jpeg_subsampling(monkeypatch, tmp_path):
+    _configure_save_paths(monkeypatch, tmp_path)
+    _configure_metadata(monkeypatch, {"prompt": "test", "seed": 1})
+    captured = _capture_save_kwargs(monkeypatch)
+
+    node = SaveImageLM()
+    node.save_images([_make_image()], "ComfyUI", "png", id="node-1")
+
+    assert "method" not in captured
+    assert "subsampling" not in captured

web/comfyui/save_image_extra_output.js

@@ -130,6 +130,35 @@ app.registerExtension({
       widget.serializeValue = () => {
         return applyTextReplacements(widget.value);
       };
+
+      // --- Conditional widget visibility for webp_method / jpeg_subsampling ---
+      const formatWidget = getWidgetByName(this, "file_format");
+      const webpMethodWidget = getWidgetByName(this, "webp_method");
+      const jpegSubWidget = getWidgetByName(this, "jpeg_subsampling");
+
+      function updateFormatConditional() {
+        const fmt = formatWidget?.value;
+        if (webpMethodWidget) {
+          webpMethodWidget.disabled = fmt !== "webp";
+          webpMethodWidget.hidden = fmt !== "webp";
+        }
+        if (jpegSubWidget) {
+          jpegSubWidget.disabled = fmt !== "jpeg";
+          jpegSubWidget.hidden = fmt !== "jpeg";
+        }
+      }
+
+      // Set initial state
+      updateFormatConditional();
+
+      // Watch for format changes
+      if (formatWidget) {
+        const origCallback = formatWidget.callback;
+        formatWidget.callback = function (value) {
+          origCallback?.call(this, value);
+          updateFormatConditional();
+        };
+      }
     });
   },
 });