chroma adjustment global chroma adjustment is carried out in block 17 cf below the original input video signal y u2032 uv in 6 results by the processing carried out in the modules 13 and 14 in the output signal y u2032 uv out1 15 that after scaling of the chrominance components u and v by the chrominance gain g c as shown in the functional block 17 results in the final output video signal y u2032 uv out2 18 in the following a detailed description of the processing actually carried out in the functional blocks 13 and 14 will be given in the histogram processing the black level is set according to a measure of the lowest level present in the image and a function dependent on the average image level the transfer function of the histogram processing block 2 is also modulated according to the input 5 of an ambient light sensor if the ambient light intensity is high the image dynamics are increased for the low image levels and vice versa in addition the histogram processing block 2 provides a chrominance scaling value the chrominance gain g c the chrominance scaling is based on the ratio of a linear transfer function with offset and the total transfer function derived by the processing the global chrominance scale value is calculated at the.