Remove y2dc/ac Q delta values from the bitstream.

Since there is no Y2, these values are always zero. This changes the
bitstream results slightly, hence a separate commit.

Change-Id: I2f838f184341868f35113ec77ca89da53c4644e0

vp9/common/vp9_onyxc_int.h

@@ -183,8 +183,6 @@ typedef struct VP9Common {
   int last_kf_gf_q;  /* Q used on the last GF or KF */
 
   int y1dc_delta_q;
-  int y2dc_delta_q_unused;
-  int y2ac_delta_q_unused;
   int uvdc_delta_q;
   int uvac_delta_q;
 

vp9/decoder/vp9_decodframe.c

@@ -1484,10 +1484,6 @@ int vp9_decode_frame(VP9D_COMP *pbi, const unsigned char **p_data_end) {
     q_update = 0;
     /* AC 1st order Q = default */
     pc->y1dc_delta_q = get_delta_q(&header_bc, pc->y1dc_delta_q, &q_update);
-    pc->y2dc_delta_q_unused = get_delta_q(&header_bc, pc->y2dc_delta_q_unused,
-                                          &q_update);
-    pc->y2ac_delta_q_unused = get_delta_q(&header_bc, pc->y2ac_delta_q_unused,
-                                          &q_update);
     pc->uvdc_delta_q = get_delta_q(&header_bc, pc->uvdc_delta_q, &q_update);
     pc->uvac_delta_q = get_delta_q(&header_bc, pc->uvac_delta_q, &q_update);
 

vp9/encoder/vp9_bitstream.c

@@ -1786,8 +1786,6 @@ void vp9_pack_bitstream(VP9_COMP *cpi, unsigned char *dest,
 
   // Transmit Dc, Second order and Uv quantizer delta information
   put_delta_q(&header_bc, pc->y1dc_delta_q);
-  put_delta_q(&header_bc, pc->y2dc_delta_q_unused);
-  put_delta_q(&header_bc, pc->y2ac_delta_q_unused);
   put_delta_q(&header_bc, pc->uvdc_delta_q);
   put_delta_q(&header_bc, pc->uvac_delta_q);
 

vp9/encoder/vp9_quantize.c

@@ -571,10 +571,8 @@ void vp9_set_quantizer(struct VP9_COMP *cpi, int Q) {
   // if any of the delta_q values are changing update flag will
   // have to be set.
   cm->y1dc_delta_q = 0;
-  cm->y2ac_delta_q_unused = 0;
   cm->uvdc_delta_q = 0;
   cm->uvac_delta_q = 0;
-  cm->y2dc_delta_q_unused = 0;
 
   // quantizer has to be reinitialized if any delta_q changes.
   // As there are not any here for now this is inactive code.