Hide coding details of fid_length/delta_fid_length

Let the writing/parsing logic do the +7/+2 offseting,
and let the rest of the code directly manipulate the actual values.

Change-Id: I460d5bf18446c028f326cb747b3c26c8d451637c

av1/av1_dx_iface.c

diff --git a/av1/av1_dx_iface.c b/av1/av1_dx_iface.c
index 1f0bb65..f5716e8 100644
--- a/av1/av1_dx_iface.c
+++ b/av1/av1_dx_iface.c
@@ -292,9 +292,7 @@
 #endif  // CONFIG_REFERENCE_BUFFER
 #if CONFIG_REFERENCE_BUFFER
     if (seq_params.frame_id_numbers_present_flag) {
-      int frame_id_len;
-      frame_id_len = seq_params.frame_id_length_minus7 + 7;
-      aom_rb_read_literal(&rb, frame_id_len);
+      aom_rb_read_literal(&rb, seq_params.frame_id_length);
     }
 #endif  // CONFIG_REFERENCE_BUFFER
     if (si->is_kf) {

av1/common/onyxc_int.h

diff --git a/av1/common/onyxc_int.h b/av1/common/onyxc_int.h
index ef31465..7ac6c0f 100644
--- a/av1/common/onyxc_int.h
+++ b/av1/common/onyxc_int.h
@@ -199,8 +199,8 @@
 /* Initial version of sequence header structure */
 typedef struct SequenceHeader {
   int frame_id_numbers_present_flag;
-  int frame_id_length_minus7;
-  int delta_frame_id_length_minus2;
+  int frame_id_length;
+  int delta_frame_id_length;
 } SequenceHeader;
 #endif  // CONFIG_REFERENCE_BUFFER
 

av1/decoder/decodeframe.c

diff --git a/av1/decoder/decodeframe.c b/av1/decoder/decodeframe.c
index 8c01962..3a80bc3 100644
--- a/av1/decoder/decodeframe.c
+++ b/av1/decoder/decodeframe.c
@@ -3367,8 +3367,8 @@
   /* Placeholder for actually reading from the bitstream */
   seq_params->frame_id_numbers_present_flag = aom_rb_read_bit(rb);
   if (seq_params->frame_id_numbers_present_flag) {
-    seq_params->frame_id_length_minus7 = aom_rb_read_literal(rb, 4);
-    seq_params->delta_frame_id_length_minus2 = aom_rb_read_literal(rb, 4);
+    seq_params->frame_id_length = aom_rb_read_literal(rb, 4) + 7;
+    seq_params->delta_frame_id_length = aom_rb_read_literal(rb, 4) + 2;
   }
 }
 #endif  // CONFIG_REFERENCE_BUFFER
@@ -3610,7 +3610,7 @@
     const int frame_to_show = cm->ref_frame_map[existing_frame_idx];
 #if CONFIG_REFERENCE_BUFFER
     if (cm->seq_params.frame_id_numbers_present_flag) {
-      int frame_id_length = cm->seq_params.frame_id_length_minus7 + 7;
+      int frame_id_length = cm->seq_params.frame_id_length;
       int display_frame_id = aom_rb_read_literal(rb, frame_id_length);
       /* Compare display_frame_id with ref_frame_id and check valid for
        * referencing */
@@ -3663,8 +3663,8 @@
   if (frame_is_intra_only(cm)) read_sequence_header(&cm->seq_params, rb);
 #endif  // !CONFIG_OBU
   if (cm->seq_params.frame_id_numbers_present_flag) {
-    int frame_id_length = cm->seq_params.frame_id_length_minus7 + 7;
-    int diff_len = cm->seq_params.delta_frame_id_length_minus2 + 2;
+    int frame_id_length = cm->seq_params.frame_id_length;
+    int diff_len = cm->seq_params.delta_frame_id_length;
     int prev_frame_id = 0;
     if (cm->frame_type != KEY_FRAME) {
       prev_frame_id = cm->current_frame_id;
@@ -3833,8 +3833,8 @@
 #endif  // CONFIG_FRAME_SIGN_BIAS
 #if CONFIG_REFERENCE_BUFFER
         if (cm->seq_params.frame_id_numbers_present_flag) {
-          int frame_id_length = cm->seq_params.frame_id_length_minus7 + 7;
-          int diff_len = cm->seq_params.delta_frame_id_length_minus2 + 2;
+          int frame_id_length = cm->seq_params.frame_id_length;
+          int diff_len = cm->seq_params.delta_frame_id_length;
           int delta_frame_id_minus1 = aom_rb_read_literal(rb, diff_len);
           int ref_frame_id =
               ((cm->current_frame_id - (delta_frame_id_minus1 + 1) +
@@ -4753,8 +4753,8 @@
 
   seq_params->frame_id_numbers_present_flag = aom_rb_read_bit(rb);
   if (seq_params->frame_id_numbers_present_flag) {
-    seq_params->frame_id_length_minus7 = aom_rb_read_literal(rb, 4);
-    seq_params->delta_frame_id_length_minus2 = aom_rb_read_literal(rb, 4);
+    seq_params->frame_id_length = aom_rb_read_literal(rb, 4) + 7;
+    seq_params->delta_frame_id_length = aom_rb_read_literal(rb, 4) + 2;
   }
 
   read_bitdepth_colorspace_sampling(cm, rb, pbi->allow_lowbitdepth);

av1/encoder/bitstream.c

diff --git a/av1/encoder/bitstream.c b/av1/encoder/bitstream.c
index 2cbee8e..cc93a2f 100644
--- a/av1/encoder/bitstream.c
+++ b/av1/encoder/bitstream.c
@@ -4149,13 +4149,13 @@
       cm->large_scale_tile ? 0 :
 #endif  // CONFIG_EXT_TILE
                            FRAME_ID_NUMBERS_PRESENT_FLAG;
-  seq_params->frame_id_length_minus7 = FRAME_ID_LENGTH_MINUS7;
-  seq_params->delta_frame_id_length_minus2 = DELTA_FRAME_ID_LENGTH_MINUS2;
+  seq_params->frame_id_length = FRAME_ID_LENGTH_MINUS7 + 7;
+  seq_params->delta_frame_id_length = DELTA_FRAME_ID_LENGTH_MINUS2 + 2;
 
   aom_wb_write_bit(wb, seq_params->frame_id_numbers_present_flag);
   if (seq_params->frame_id_numbers_present_flag) {
-    aom_wb_write_literal(wb, seq_params->frame_id_length_minus7, 4);
-    aom_wb_write_literal(wb, seq_params->delta_frame_id_length_minus2, 4);
+    aom_wb_write_literal(wb, seq_params->frame_id_length - 7, 4);
+    aom_wb_write_literal(wb, seq_params->delta_frame_id_length - 2, 4);
   }
 }
 #endif  // CONFIG_REFERENCE_BUFFER
@@ -4347,7 +4347,7 @@
 
 #if CONFIG_REFERENCE_BUFFER
     if (cm->seq_params.frame_id_numbers_present_flag) {
-      int frame_id_len = cm->seq_params.frame_id_length_minus7 + 7;
+      int frame_id_len = cm->seq_params.frame_id_length;
       int display_frame_id = cm->ref_frame_id[cpi->existing_fb_idx_to_show];
       aom_wb_write_literal(wb, display_frame_id, frame_id_len);
       /* Add a zero byte to prevent emulation of superframe marker */
@@ -4376,7 +4376,7 @@
 #if CONFIG_REFERENCE_BUFFER
   cm->invalid_delta_frame_id_minus1 = 0;
   if (cm->seq_params.frame_id_numbers_present_flag) {
-    int frame_id_len = cm->seq_params.frame_id_length_minus7 + 7;
+    int frame_id_len = cm->seq_params.frame_id_length;
     aom_wb_write_literal(wb, cm->current_frame_id, frame_id_len);
   }
 #endif  // CONFIG_REFERENCE_BUFFER
@@ -4451,8 +4451,8 @@
 #if CONFIG_REFERENCE_BUFFER
         if (cm->seq_params.frame_id_numbers_present_flag) {
           int i = get_ref_frame_map_idx(cpi, ref_frame);
-          int frame_id_len = cm->seq_params.frame_id_length_minus7 + 7;
-          int diff_len = cm->seq_params.delta_frame_id_length_minus2 + 2;
+          int frame_id_len = cm->seq_params.frame_id_length;
+          int diff_len = cm->seq_params.delta_frame_id_length;
           int delta_frame_id_minus1 =
               ((cm->current_frame_id - cm->ref_frame_id[i] +
                 (1 << frame_id_len)) %
@@ -4628,7 +4628,7 @@
 
 #if CONFIG_REFERENCE_BUFFER
     if (cm->seq_params.frame_id_numbers_present_flag) {
-      int frame_id_len = cm->seq_params.frame_id_length_minus7 + 7;
+      int frame_id_len = cm->seq_params.frame_id_length;
       int display_frame_id = cm->ref_frame_id[cpi->existing_fb_idx_to_show];
       aom_wb_write_literal(wb, display_frame_id, frame_id_len);
       /* Add a zero byte to prevent emulation of superframe marker */
@@ -4654,7 +4654,7 @@
 #if CONFIG_REFERENCE_BUFFER
   cm->invalid_delta_frame_id_minus1 = 0;
   if (cm->seq_params.frame_id_numbers_present_flag) {
-    int frame_id_len = cm->seq_params.frame_id_length_minus7 + 7;
+    int frame_id_len = cm->seq_params.frame_id_length;
     aom_wb_write_literal(wb, cm->current_frame_id, frame_id_len);
   }
 #endif  // CONFIG_REFERENCE_BUFFER
@@ -4730,8 +4730,8 @@
 #if CONFIG_REFERENCE_BUFFER
       if (cm->seq_params.frame_id_numbers_present_flag) {
         int i = get_ref_frame_map_idx(cpi, ref_frame);
-        int frame_id_len = cm->seq_params.frame_id_length_minus7 + 7;
-        int diff_len = cm->seq_params.delta_frame_id_length_minus2 + 2;
+        int frame_id_len = cm->seq_params.frame_id_length;
+        int diff_len = cm->seq_params.delta_frame_id_length;
         int delta_frame_id_minus1 =
             ((cm->current_frame_id - cm->ref_frame_id[i] +
               (1 << frame_id_len)) %
@@ -4795,8 +4795,8 @@
 #if CONFIG_REFERENCE_BUFFER
       if (cm->seq_params.frame_id_numbers_present_flag) {
         int i = get_ref_frame_map_idx(cpi, ref_frame);
-        int frame_id_len = cm->seq_params.frame_id_length_minus7 + 7;
-        int diff_len = cm->seq_params.delta_frame_id_length_minus2 + 2;
+        int frame_id_len = cm->seq_params.frame_id_length;
+        int diff_len = cm->seq_params.delta_frame_id_length;
         int delta_frame_id_minus1 =
             ((cm->current_frame_id - cm->ref_frame_id[i] +
               (1 << frame_id_len)) %
@@ -5237,10 +5237,10 @@
   seq_params->frame_id_numbers_present_flag = FRAME_ID_NUMBERS_PRESENT_FLAG;
   aom_wb_write_literal(&wb, seq_params->frame_id_numbers_present_flag, 1);
   if (seq_params->frame_id_numbers_present_flag) {
-    seq_params->frame_id_length_minus7 = FRAME_ID_LENGTH_MINUS7;
-    seq_params->delta_frame_id_length_minus2 = DELTA_FRAME_ID_LENGTH_MINUS2;
-    aom_wb_write_literal(&wb, seq_params->frame_id_length_minus7, 4);
-    aom_wb_write_literal(&wb, seq_params->delta_frame_id_length_minus2, 4);
+    seq_params->frame_id_length = FRAME_ID_LENGTH_MINUS7 + 7;
+    seq_params->delta_frame_id_length = DELTA_FRAME_ID_LENGTH_MINUS2 + 2;
+    aom_wb_write_literal(&wb, seq_params->frame_id_length - 7, 4);
+    aom_wb_write_literal(&wb, seq_params->delta_frame_id_length - 2, 4);
   }
 
   // color_config