ref: f99b9cae6a3dc5775a83b264d6041be8d5d416d6
dir: /sys/src/cmd/python/Modules/yuvconvert.c/
#include "yuv.h" void yuv_sv411_to_cl422dc(int invert, void *data, void *yuv, int width, int height) { struct yuv411 *in = data; struct yuv422 *out_even = yuv; struct yuv422 *out_odd = out_even + width / 2; int i, j; /* counters */ for (i = height / 2; i--; ) { for (j = width / 4; j--; ) { YUV422_Y0(*out_even) = YUV411_Y00(*in); YUV422_U0(*out_even) = YUV411_U00(*in); YUV422_V0(*out_even) = YUV411_V00(*in); YUV422_Y1(*out_even) = YUV411_Y01(*in); out_even++; YUV422_Y0(*out_even) = YUV411_Y02(*in); YUV422_U0(*out_even) = YUV411_U02(*in); YUV422_V0(*out_even) = YUV411_V02(*in); YUV422_Y1(*out_even) = YUV411_Y03(*in); out_even++; YUV422_Y0(*out_odd) = YUV411_Y10(*in); YUV422_U0(*out_odd) = YUV411_U10(*in); YUV422_V0(*out_odd) = YUV411_V10(*in); YUV422_Y1(*out_odd) = YUV411_Y11(*in); out_odd++; YUV422_Y0(*out_odd) = YUV411_Y12(*in); YUV422_U0(*out_odd) = YUV411_U12(*in); YUV422_V0(*out_odd) = YUV411_V12(*in); YUV422_Y1(*out_odd) = YUV411_Y13(*in); out_odd++; in++; } out_even += width / 2; out_odd += width / 2; } } void yuv_sv411_to_cl422dc_quartersize(int invert, void *data, void *yuv, int width, int height) { int w4 = width / 4; /* quarter of width is used often */ struct yuv411 *in_even = data; struct yuv411 *in_odd = in_even + w4; struct yuv422 *out_even = yuv; struct yuv422 *out_odd = out_even + w4; int i, j; /* counters */ int u, v; /* U and V values */ for (i = height / 4; i--; ) { for (j = w4; j--; ) { u = YUV411_U00(*in_even); v = YUV411_V00(*in_even); YUV422_Y0(*out_even) = YUV411_Y00(*in_even); YUV422_U0(*out_even) = u; YUV422_V0(*out_even) = v; YUV422_Y1(*out_even) = YUV411_Y02(*in_even); YUV422_Y0(*out_odd) = YUV411_Y10(*in_odd); YUV422_U0(*out_odd) = u; YUV422_V0(*out_odd) = v; YUV422_Y1(*out_odd) = YUV411_Y12(*in_odd); in_even++; in_odd++; out_even++; out_odd++; } in_even += w4; in_odd += w4; out_even += w4; out_odd += w4; } } void yuv_sv411_to_cl422dc_sixteenthsize(int invert, void *data, void *yuv, int width, int height) { int w4_3 = 3 * width / 4; /* three quarters of width is used often */ int w8 = width / 8; /* and so is one eighth */ struct yuv411 *in_even = data; struct yuv411 *in_odd = in_even + width / 2; struct yuv422 *out_even = yuv; struct yuv422 *out_odd = out_even + w8; int i, j; /* counters */ int u, v; /* U and V values */ for (i = height / 8; i--; ) { for (j = w8; j--; ) { u = YUV411_U00(in_even[0]); v = YUV411_V00(in_even[0]); YUV422_Y0(*out_even) = YUV411_Y00(in_even[0]); YUV422_U0(*out_even) = u; YUV422_V0(*out_even) = v; YUV422_Y1(*out_even) = YUV411_Y00(in_even[1]); YUV422_Y0(*out_odd) = YUV411_Y00(in_odd[0]); YUV422_U0(*out_odd) = u; YUV422_V0(*out_odd) = v; YUV422_Y1(*out_odd) = YUV411_Y00(in_even[1]); in_even += 2; in_odd += 2; out_even++; out_odd++; } in_even += w4_3; in_odd += w4_3; out_even += w8; out_odd += w8; } }