From 090d675e3c577944a0d48d1fa588cdeb71e6264d Mon Sep 17 00:00:00 2001
From: tinysolver <iam.tinysolver@gmail.com>
Date: Sat, 3 Oct 2026 15:41:06 +0900
Subject: [PATCH] fix(openrouter): map ImageGenerationRequestQuality members to
 a gemini tier

litellm.image_generation takes quality as a string or an
ImageGenerationRequestQuality member. The tier lookup used str(quality),
which gives "ImageGenerationRequestQuality.MEDIUM" for a member, so low,
medium, high and auto got no tier on google/ models and quality was dropped.
The lookup now uses the value itself, as the chat-based path did
---
 .../image_generation/transformation.py        |  3 ++-
 ...est_openrouter_image_gen_transformation.py | 21 +++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/litellm/llms/openrouter/image_generation/transformation.py b/litellm/llms/openrouter/image_generation/transformation.py
index 19c94144c54..481d165c93d 100644
--- a/litellm/llms/openrouter/image_generation/transformation.py
+++ b/litellm/llms/openrouter/image_generation/transformation.py
@@ -118,7 +118,8 @@ class OpenRouterImageGenerationConfig(BaseImageGenerationConfig):
         ratio of an OpenAI pixel size. A tier size or an image_config set by the caller wins
         """
         size: Final = str(mapped_params.get("size") or "")
-        tier: Final = QUALITY_RESOLUTION_TIERS.get(str(mapped_params["quality"]))
+        quality: Final = mapped_params["quality"]
+        tier: Final = QUALITY_RESOLUTION_TIERS.get(quality) if isinstance(quality, str) else None
         params: Final = {key: value for key, value in mapped_params.items() if key != "quality"}
         if tier is None or (size and PIXEL_SIZE.fullmatch(size) is None):
             return params
diff --git a/tests/unit/llms/openrouter/image_generation/test_openrouter_image_gen_transformation.py b/tests/unit/llms/openrouter/image_generation/test_openrouter_image_gen_transformation.py
index f5ec6a15a54..3b323261421 100644
--- a/tests/unit/llms/openrouter/image_generation/test_openrouter_image_gen_transformation.py
+++ b/tests/unit/llms/openrouter/image_generation/test_openrouter_image_gen_transformation.py
@@ -12,6 +12,7 @@ from litellm.llms.openrouter.common_utils import OpenRouterException
 from litellm.llms.openrouter.image_generation.transformation import (
     OpenRouterImageGenerationConfig,
 )
+from litellm.types.llms.openai import ImageGenerationRequestQuality
 from litellm.types.utils import ImageResponse, ImageUsage, ImageUsageInputTokensDetails
 
 CONFIG: Final = OpenRouterImageGenerationConfig()
@@ -235,6 +236,26 @@ def test_map_openai_params_quality_tier_yields_to_an_image_config_already_set():
     assert mapped == {"image_config": {"image_size": "1K"}, "quality": "high", "size": "1536x1024"}
 
 
+@pytest.mark.parametrize("quality", list(ImageGenerationRequestQuality))
+def test_map_openai_params_reads_a_quality_enum_member_like_its_string(quality: ImageGenerationRequestQuality):
+    """litellm.image_generation takes ImageGenerationRequestQuality members as quality"""
+    from_enum = CONFIG.map_openai_params(
+        non_default_params={"quality": quality, "size": "1024x1024"},
+        optional_params={},
+        model=RESOLUTION_TIER_MODEL,
+        drop_params=False,
+    )
+    from_string = CONFIG.map_openai_params(
+        non_default_params={"quality": quality.value, "size": "1024x1024"},
+        optional_params={},
+        model=RESOLUTION_TIER_MODEL,
+        drop_params=False,
+    )
+
+    assert from_enum == from_string
+    assert "image_size" in from_enum["image_config"]
+
+
 @patch("litellm.llms.openrouter.image_generation.transformation.get_secret_str")
 def test_validate_environment_with_api_key(mock_get_secret: MagicMock):
     result = CONFIG.validate_environment(