static void chroma_4mv_motion(MpegEncContext *s, uint8_t *dest_cb, uint8_t *dest_cr, uint8_t **ref_picture, op_pixels_func *pix_op, int mx, int my) { int dxy, emu=0, src_x, src_y, offset; uint8_t *ptr; /* In case of 8X8, we construct a single chroma motion vector with a special rounding */ mx= ff_h263_round_chroma(mx); my= ff_h263_round_chroma(my); dxy = ((my & 1) << 1) | (mx & 1); mx >>= 1; my >>= 1; src_x = s->mb_x * 8 + mx; src_y = s->mb_y * 8 + my; src_x = av_clip(src_x, -8, (s->width >> 1)); if (src_x == (s->width >> 1)) dxy &= ~1; src_y = av_clip(src_y, -8, (s->height >> 1)); if (src_y == (s->height >> 1)) dxy &= ~2; offset = src_y * s->uvlinesize + src_x; ptr = ref_picture[1] + offset; if(s->flags&CODEC_FLAG_EMU_EDGE){ if( (unsigned)src_x > FFMAX((s->h_edge_pos>>1) - (dxy &1) - 8, 0) || (unsigned)src_y > FFMAX((s->v_edge_pos>>1) - (dxy>>1) - 8, 0)){ s->vdsp.emulated_edge_mc(s->edge_emu_buffer, ptr, s->uvlinesize, 9, 9, src_x, src_y, s->h_edge_pos>>1, s->v_edge_pos>>1); ptr= s->edge_emu_buffer; emu=1; } } pix_op[dxy](dest_cb, ptr, s->uvlinesize, 8); ptr = ref_picture[2] + offset; if(emu){ s->vdsp.emulated_edge_mc(s->edge_emu_buffer, ptr, s->uvlinesize, 9, 9, src_x, src_y, s->h_edge_pos>>1, s->v_edge_pos>>1); ptr= s->edge_emu_buffer; } pix_op[dxy](dest_cr, ptr, s->uvlinesize, 8); }