{"record":{"id":"a079c08caddf9c96","repo":"keras-team/keras","slug":"brightness-range-should-be-tuple-or-list-of-two-f","errorCode":null,"errorMessage":"`brightness_range should be tuple or list of two floats. Received: {brightness_range}","messagePattern":"`brightness_range should be tuple or list of two floats\\. Received: (.+?)","errorType":"exception","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"keras/src/legacy/preprocessing/image.py","lineNumber":1082,"sourceCode":"                    \"`featurewise_std_normalization`, \"\n                    \"which overrides setting of \"\n                    \"`featurewise_center`.\"\n                )\n        if samplewise_std_normalization:\n            if not samplewise_center:\n                self.samplewise_center = True\n                warnings.warn(\n                    \"This ImageDataGenerator specifies \"\n                    \"`samplewise_std_normalization`, \"\n                    \"which overrides setting of \"\n                    \"`samplewise_center`.\"\n                )\n        if brightness_range is not None:\n            if (\n                not isinstance(brightness_range, (tuple, list))\n                or len(brightness_range) != 2\n            ):\n                raise ValueError(\n                    \"`brightness_range should be tuple or list of two floats. \"\n                    f\"Received: {brightness_range}\"\n                )\n        self.brightness_range = brightness_range\n\n    def flow(\n        self,\n        x,\n        y=None,\n        batch_size=32,\n        shuffle=True,\n        sample_weight=None,\n        seed=None,\n        save_to_dir=None,\n        save_prefix=\"\",\n        save_format=\"png\",\n        ignore_class_split=False,\n        subset=None,","sourceCodeStart":1064,"sourceCodeEnd":1100,"githubUrl":"https://github.com/keras-team/keras/blob/7a34a03db60bf60042242d6a556fc3be119046a5/keras/src/legacy/preprocessing/image.py#L1064-L1100","documentation":"brightness_range, if given, must be a tuple or list of exactly two elements (typically floats bounding the random brightness shift).","triggerScenarios":"ImageDataGenerator(brightness_range=0.5) (scalar) or brightness_range=[0.5,1.5,2.0].","commonSituations":"Assuming scalar like zoom_range; YAML tuple parsed as list of wrong length.","solutions":["Use brightness_range=[0.5, 1.5] (2 elements, tuple or list)","Omit it for no brightness augmentation"],"exampleFix":"// before\nImageDataGenerator(brightness_range=0.5)\n// after\nImageDataGenerator(brightness_range=[0.5, 1.5])\n","handlingStrategy":"validation","validationCode":"assert brightness_range is None or (isinstance(brightness_range,(list,tuple)) and len(brightness_range)==2)","typeGuard":"def br_ok(b): return b is None or (isinstance(b,(list,tuple)) and len(b)==2)","tryCatchPattern":"try: ImageDataGenerator(brightness_range=b)\nexcept ValueError as e: if 'brightness_range' in str(e): b = [0.5, 1.5]","preventionTips":["Remember brightness_range has no scalar shorthand"],"tags":["keras","data-augmentation","argument-validation"],"backgroundTag":"invalid-argument-value","analyzedSha":"7a34a03db60bf60042242d6a556fc3be119046a5","analyzedAt":"2026-08-25T21:25:25.994Z","schemaVersion":2},"datasetVersion":"2026-08-26T02:17:13.382Z"}