static int ipvideo_decode_block_opcode_0x3(IpvideoContext *s) { unsigned char B; int x, y; /* copy 8x8 block from current frame from an up/left block */ /* need 1 more byte for motion */ CHECK_STREAM_PTR(1); B = *s->stream_ptr++; if (B < 56) { x = -(8 + (B % 7)); y = -(B / 7); } else { x = -(-14 + ((B - 56) % 29)); y = -( 8 + ((B - 56) / 29)); } debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y); return copy_from(s, &s->current_frame, x, y); }