AV1_COMMON: doc for vars related to MFMV and SVC
BUG=aomedia:2610
Change-Id: I155ca2bfcc5d90174c56c5968f5a4b88095060b5
diff --git a/av1/common/av1_common_int.h b/av1/common/av1_common_int.h
index 10fe15b..942edf2 100644
--- a/av1/common/av1_common_int.h
+++ b/av1/common/av1_common_int.h
@@ -652,19 +652,38 @@
// MACROBLOCKD struct, as they have a fixed size.
CommonContexts above_contexts;
+ // When cm->seq_params.frame_id_numbers_present_flag == 1, current and
+ // reference frame IDs are signaled in the bitstream.
int current_frame_id;
int ref_frame_id[REF_FRAMES];
- TPL_MV_REF *tpl_mvs;
- int tpl_mvs_mem_size;
- int ref_frame_sign_bias[REF_FRAMES]; /* Two state 0, 1 */
+ // Motion vectors provided by motion field estimation.
+ // tpl_mvs[row * stride + col] stores MV for block at [mi_row, mi_col] where:
+ // mi_row = 2 * row,
+ // mi_col = 2 * col, and
+ // stride = cm->mi_params.mi_stride / 2
+ TPL_MV_REF *tpl_mvs;
+ // Allocated size of 'tpl_mvs' array. Refer to 'ensure_mv_buffer()' function.
+ int tpl_mvs_mem_size;
+ // ref_frame_sign_bias[k] is 1 if relative distance between reference 'k' and
+ // current frame is positive; and 0 otherwise.
+ int ref_frame_sign_bias[REF_FRAMES];
+ // ref_frame_side[k] is 1 if relative distance between reference 'k' and
+ // current frame is positive, -1 if relative distance is 0; and 0 otherwise.
// TODO(jingning): This can be combined with sign_bias later.
int8_t ref_frame_side[REF_FRAMES];
- int temporal_layer_id;
- int spatial_layer_id;
+ // Number of temporal layers: may be > 1 for SVC (scalable vector coding).
unsigned int number_temporal_layers;
+ // Temporal layer ID of this frame
+ // (in the range 0 ... (number_temporal_layers - 1)).
+ int temporal_layer_id;
+
+ // Number of spatial layers: may be > 1 for SVC (scalable vector coding).
unsigned int number_spatial_layers;
+ // Spatial layer ID of this frame
+ // (in the range 0 ... (number_spatial_layers - 1)).
+ int spatial_layer_id;
#if TXCOEFF_TIMER
int64_t cum_txcoeff_timer;