yuv2planeX_16_c_template(const int16_t *filter, int filterSize, const int32_t **src, uint16_t *dest, int dstW, int big_endian, int output_bits) { int i; int shift = 15; av_assert0(output_bits == 16); for (i = 0; i < dstW; i++) { int val = 1 << (shift - 1); int j; /* range of val is [0,0x7FFFFFFF], so 31 bits, but with lanczos/spline * filters (or anything with negative coeffs, the range can be slightly * wider in both directions. To account for this overflow, we subtract * a constant so it always fits in the signed range (assuming a * reasonable filterSize), and re-add that at the end. */ val -= 0x40000000; for (j = 0; j < filterSize; j++) val += src[j][i] * filter[j]; output_pixel(&dest[i], val, 0x8000, int); } }