os04c10: 12bit tune (#33947)

* much better

* also isp

---------

Co-authored-by: Comma Device <device@comma.ai>

system/camerad/sensors/os04c10.cc

@@ -70,7 +70,7 @@ OS04C10::OS04C10() {
   };
   for (int i = 0; i < 65; i++) {
     float fx = i / 64.0;
-    gamma_lut_rgb.push_back((uint32_t)(pow(fx, 0.7)*1023.0 + 0.5));
+    gamma_lut_rgb.push_back((uint32_t)((10*fx)/(1+9*fx)*1023.0 + 0.5));
   }
   prepare_gamma_lut();
   linearization_lut = {

system/camerad/sensors/os04c10_cl.h

@@ -52,11 +52,7 @@ float3 color_correct(float3 rgb) {
 }
 
 float3 apply_gamma(float3 rgb, int expo_time) {
-  return powr(rgb, 0.7);
+  return (10 * rgb) / (1 + 9 * rgb);
-/*float s = log2((float)expo_time);
-  if (s < 6) {s = fmin(12.0 - s, 9.0);}
-  // log function adaptive to number of bits
-  return clamp(log(1 + rgb*(PV_MAX16 - BLACK_LVL)) * (0.48*s*s - 12.92*s + 115.0) - (1.08*s*s - 29.2*s + 260.0), 0.0, 255.0) / 255.0;*/
 }
 
 #endif