{"record":{"id":"745654a7b22fd8e0","repo":"keras-team/keras","slug":"fft-length-should-be-not-less-than-frame-length","errorCode":null,"errorMessage":"`fft_length` should be not less than `frame_length`. Received fft_length={fft_length}, frame_length={frame_length}","messagePattern":"`fft_length` should be not less than `frame_length`\\. Received fft_length=(.+?), frame_length=(.+?)","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"keras/src/layers/preprocessing/stft_spectrogram.py","lineNumber":158,"sourceCode":"        window=\"hann\",\n        periodic=False,\n        scaling=\"density\",\n        padding=\"valid\",\n        expand_dims=False,\n        data_format=None,\n        **kwargs,\n    ):\n        if frame_step is not None and (\n            frame_step > frame_length or frame_step < 1\n        ):\n            raise ValueError(\n                \"`frame_step` should be a positive integer not greater than \"\n                f\"`frame_length`. Received frame_step={frame_step}, \"\n                f\"frame_length={frame_length}\"\n            )\n\n        if fft_length is not None and fft_length < frame_length:\n            raise ValueError(\n                \"`fft_length` should be not less than `frame_length`. \"\n                f\"Received fft_length={fft_length}, frame_length={frame_length}\"\n            )\n\n        if fft_length is not None and (fft_length & -fft_length) != fft_length:\n            warnings.warn(\n                \"`fft_length` is recommended to be a power of two. \"\n                f\"Received fft_length={fft_length}\"\n            )\n\n        all_modes = [\"log\", \"magnitude\", \"psd\", \"real\", \"imag\", \"angle\", \"stft\"]\n\n        if mode not in all_modes:\n            raise ValueError(\n                \"Output mode is invalid, it must be one of \"\n                f\"{', '.join(all_modes)}. Received: mode={mode}\"\n            )\n","sourceCodeStart":140,"sourceCodeEnd":176,"githubUrl":"https://github.com/keras-team/keras/blob/7a34a03db60bf60042242d6a556fc3be119046a5/keras/src/layers/preprocessing/stft_spectrogram.py#L140-L176","documentation":"Error \"`fft_length` should be not less than `frame_length`. Received fft_length={fft_length}, frame_length={frame_length}\" thrown in keras-team/keras.","triggerScenarios":"Thrown at keras/src/layers/preprocessing/stft_spectrogram.py:158 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"7a34a03db60bf60042242d6a556fc3be119046a5","analyzedAt":"2026-08-25T21:25:25.994Z","schemaVersion":2},"datasetVersion":"2026-08-26T02:17:13.382Z"}