An imaging apparatus comprising: a first pixel configured to generate a signal by photoelectric conversion; a second pixel, arranged in a row same as that in which the first pixel is arranged, configured to generate a signal by photoelectric conversion, wherein color filters (R, Gr, Gb, B) respectively having a same color are provided on the first pixel and the second pixel; a first comparator configured to compare the signal based on the first pixel with a first reference signal (RAMP_A) having a sloped waveform of which a level is changed according to passage of time; a second comparator configured to compare the signal based on the second pixel with a second reference signal (RAMP_B) having a sloped waveform of which a rate of change for passage of time is different from that of the first reference signal; a first counter configured to perform counting until the first comparator outputs a signal indicating that a magnitude relation of the signal based on the first pixel and the first reference signal (RAMP_A) is inverted; a second counter configured to perform counting until the second comparator outputs a signal indicating that a magnitude relation of the signal based on the second pixel and the second reference signal (RAMP_B) is inverted; and a processing unit (206, 401) configured to generate one pixel signal for the first pixel and the second pixel based on a count value of the first counter and/or a count value of the second counter, wherein the rate of change of the second reference signal (RAMP_B) for passage of time is larger than the rate of change of the first reference signal (RAMP_A) for passage of time, in a case where the magnitude relation of the signal based on the first pixel and the first reference signal (RAMP_A) is not inverted and the magnitude relation of the signal based on the second pixel and the second reference signal (RAMP_B) is inverted, the processing unit (206, 401) generates the one pixel signal by selecting the count value of the second counter, and in a case where the magnitude relation of the signal based on the first pixel and the first reference signal (RAMP_A) is inverted and the magnitude relation of the signal based on the second pixel and the second reference signal (RAMP_B) is inverted, the processing unit (206, 401) generates the one pixel signal by selecting the count value of the first counter or by synthesizing the count value of the first counter and the count value of the second counter. a first pixel configured to generate a signal by photoelectric conversion; a second pixel, arranged in a row same as that in which the first pixel is arranged, configured to generate a signal by photoelectric conversion, wherein color filters (R, Gr, Gb, B) respectively having a same color are provided on the first pixel and the second pixel; a first comparator configured to compare the signal based on the first pixel with a first reference signal (RAMP_A) having a sloped waveform of which a level is changed according to passage of time; a second comparator configured to compare the signal based on the second pixel with a second reference signal (RAMP_B) having a sloped waveform of which a rate of change for passage of time is different from that of the first reference signal; a first counter configured to perform counting until the first comparator outputs a signal indicating that a magnitude relation of the signal based on the first pixel and the first reference signal (RAMP_A) is inverted; a second counter configured to perform counting until the second comparator outputs a signal indicating that a magnitude relation of the signal based on the second pixel and the second reference signal (RAMP_B) is inverted; and a processing unit (206, 401) configured to generate one pixel signal for the first pixel and the second pixel based on a count value of the first counter and/or a count value of the second counter, wherein the rate of change of the second reference signal (RAMP_B) for passage of time is larger than the rate of change of the first reference signal (RAMP_A) for passage of time, in a case where the magnitude relation of the signal based on the first pixel and the first reference signal (RAMP_A) is not inverted and the magnitude relation of the signal based on the second pixel and the second reference signal (RAMP_B) is inverted, the processing unit (206, 401) generates the one pixel signal by selecting the count value of the second counter, and in a case where the magnitude relation of the signal based on the first pixel and the first reference signal (RAMP_A) is inverted and the magnitude relation of the signal based on the second pixel and the second reference signal (RAMP_B) is inverted, the processing unit (206, 401) generates the one pixel signal by selecting the count value of the first counter or by synthesizing the count value of the first counter and the count value of the second counter.