#ifndef LG_HISTOGRAM_H
#define LG_HISTOGRAM_H
#include <stdint.h>
#include <stddef.h>
/* LG ABI: region ID followed by three planar channels, 256 uint16 bins
 * per channel. Bin index is the 8-bit intensity (0..255). */
typedef struct { uint32_t id; uint16_t bins[3][256]; } Histogram;
_Static_assert(sizeof(Histogram)==0x604,"LG ABI record size");
_Static_assert(offsetof(Histogram,bins)==4,"LG ABI channel offset");
static inline unsigned char histogram_mean(const uint16_t bins[256]) {
 uint64_t count=0,weight=0;
 for(unsigned b=0;b<256;b++){count+=bins[b];weight+=(uint64_t)bins[b]*b;}
 return count?(unsigned char)((weight+count/2)/count):0;
}
#endif