int vshift = s->sps->vshift[c_idx];
uint8_t *dst = &s->frame->data[c_idx][(y0 >> vshift) * stride +
((x0 >> hshift) << s->sps->pixel_shift)];
int vshift = s->sps->vshift[c_idx];
uint8_t *dst = &s->frame->data[c_idx][(y0 >> vshift) * stride +
((x0 >> hshift) << s->sps->pixel_shift)];