A light driver for driving at least one light source arranged to emit coded light based on a control signal, the light driver comprising: a receiver arranged to receive a sequence u = [u 1,..., u k,..., u K] of source symbols u k representing an information sequence of an information source; a processing unit arranged to determine, from the sequence of source symbols, a sequence z = [z 1,..., z k,..., z K] of channel symbols z k forming the control signal; a transmitter arranged to provide the at least one light source with the control signal thereby driving the at least one light source to transmit a waveform representing the channel symbols; wherein the processing unit is arranged to determine the sequence of channel symbols z by mapping each source symbol u k at time k to a composite channel symbol z k = (z k,1, z k,2) comprising at least one first channel symbol z k,1 which is identical to u k, and further comprising at least one second channel symbol z k,2, the mapping resulting in that the power spectral density at frequency zero of the sequence z of channel symbols is equal to zero, and wherein the control signal thereby enables no visible flicker to be present in coded light emitted by the at least one light source; characterized in that said power spectral density is achieved by: for each of the source symbols u k, the second channel symbol z k,2 being a signed average or signed weighted average of the source symbol u k and at least one future and/or past source symbol u i, i ≠ k, the second channel symbols thus serving as merging symbols to smooth transitions in the waveform. a receiver arranged to receive a sequence u = [u 1,..., u k,..., u K] of source symbols u k representing an information sequence of an information source; a processing unit arranged to determine, from the sequence of source symbols, a sequence z = [z 1,..., z k,..., z K] of channel symbols z k forming the control signal; a transmitter arranged to provide the at least one light source with the control signal thereby driving the at least one light source to transmit a waveform representing the channel symbols; wherein the processing unit is arranged to determine the sequence of channel symbols z by mapping each source symbol u k at time k to a composite channel symbol z k = (z k,1, z k,2) comprising at least one first channel symbol z k,1 which is identical to u k, and further comprising at least one second channel symbol z k,2, the mapping resulting in that the power spectral density at frequency zero of the sequence z of channel symbols is equal to zero, and wherein the control signal thereby enables no visible flicker to be present in coded light emitted by the at least one light source; characterized in that said power spectral density is achieved by: for each of the source symbols u k, the second channel symbol z k,2 being a signed average or signed weighted average of the source symbol u k and at least one future and/or past source symbol u i, i ≠ k, the second channel symbols thus serving as merging symbols to smooth transitions in the waveform. for each of the source symbols u k, the second channel symbol z k,2 being a signed average or signed weighted average of the source symbol u k and at least one future and/or past source symbol u i, i ≠ k, the second channel symbols thus serving as merging symbols to smooth transitions in the waveform.