A device for electrocardiogram signal processing, the device comprising: a single-lead electrocardiogram measurement device operable to obtain a time-domain electrocardiogram signal from a patient; at least one electronic processor (20, 30) programmed to carry out the steps of: receiving a time-domain electrocardiogram signal from the single-lead ECG measurement device; determining a signal quality index of the time-domain electrocardiogram signal over a time interval; generating a time-frequency representation of the time-domain electrocardiogram signal acquired over the time interval, by converting said time-domain electrocardiogram signal to a two-dimensional time-frequency dataset using a sliding window; processing the time-frequency representation using a neural network to output probabilities for rhythms of a set of rhythms including at least atrial fibrillation; assigning a rhythm for the time-domain electrocardiogram signal based on the signal quality index and probabilities for the rhythms of the set of rhythms output by the neural network wherein assigning includes assigning a noisy recording for the time-domain electrocardiogram signal if the determined signal quality index is below a preselected signal quality index threshold; and controlling a display device to display the rhythm or noisy recording assigned to the time-domain electrocardiogram signal. a single-lead electrocardiogram measurement device operable to obtain a time-domain electrocardiogram signal from a patient; at least one electronic processor (20, 30) programmed to carry out the steps of: receiving a time-domain electrocardiogram signal from the single-lead ECG measurement device; determining a signal quality index of the time-domain electrocardiogram signal over a time interval; generating a time-frequency representation of the time-domain electrocardiogram signal acquired over the time interval, by converting said time-domain electrocardiogram signal to a two-dimensional time-frequency dataset using a sliding window; processing the time-frequency representation using a neural network to output probabilities for rhythms of a set of rhythms including at least atrial fibrillation; assigning a rhythm for the time-domain electrocardiogram signal based on the signal quality index and probabilities for the rhythms of the set of rhythms output by the neural network wherein assigning includes assigning a noisy recording for the time-domain electrocardiogram signal if the determined signal quality index is below a preselected signal quality index threshold; and controlling a display device to display the rhythm or noisy recording assigned to the time-domain electrocardiogram signal. receiving a time-domain electrocardiogram signal from the single-lead ECG measurement device; determining a signal quality index of the time-domain electrocardiogram signal over a time interval; generating a time-frequency representation of the time-domain electrocardiogram signal acquired over the time interval, by converting said time-domain electrocardiogram signal to a two-dimensional time-frequency dataset using a sliding window; processing the time-frequency representation using a neural network to output probabilities for rhythms of a set of rhythms including at least atrial fibrillation; assigning a rhythm for the time-domain electrocardiogram signal based on the signal quality index and probabilities for the rhythms of the set of rhythms output by the neural network wherein assigning includes assigning a noisy recording for the time-domain electrocardiogram signal if the determined signal quality index is below a preselected signal quality index threshold; and controlling a display device to display the rhythm or noisy recording assigned to the time-domain electrocardiogram signal.