AV1 RT: Add more documentation to nonRD inter mode search
BUG=aomedia:2714
Change-Id: Id905fad8196114d44239f330bf5c20d8f1244b8c
diff --git a/av1/encoder/nonrd_pickmode.c b/av1/encoder/nonrd_pickmode.c
index 92b0deb..2a14a7b 100644
--- a/av1/encoder/nonrd_pickmode.c
+++ b/av1/encoder/nonrd_pickmode.c
@@ -736,6 +736,27 @@
rd_stats->dist = dist;
}
+/*!\brief Calculates RD Cost using Hadamard transform.
+ *
+ * \ingroup inter_mode_search
+ * \callgraph
+ * \callergraph
+ * Calculates RD Cost using Hadamard transform. For low bit depth this function
+ * uses low-precision set of functions (16-bit) and 32 bit for high bit depth
+ * \param[in] cpi Top-level encoder structure
+ * \param[in] x Pointer to structure holding all the data for
+ the current macroblock
+ * \param[in] mi_row Row index in 4x4 units
+ * \param[in] mi_col Column index in 4x4 units
+ * \param[in] this_rdc Pointer to calculated RD Cost
+ * \param[in] skippable Pointer to a flag indicating possible tx skip
+ * \param[in] bsize Current block size
+ * \param[in] tx_size Transform size
+ *
+ * \return Nothing is returned. Instead, calculated RD cost is placed to
+ * \c this_rdc. \c skippable flag is set if there is no non-zero quantized
+ * coefficients for Hadamard transform
+ */
static void block_yrd(AV1_COMP *cpi, MACROBLOCK *x, int mi_row, int mi_col,
RD_STATS *this_rdc, int *skippable, BLOCK_SIZE bsize,
TX_SIZE tx_size) {
@@ -1310,6 +1331,38 @@
}
#define FILTER_SEARCH_SIZE 2
+/*!\brief Searches for the best intrpolation filter
+ *
+ * \ingroup inter_mode_search
+ * \callgraph
+ * \callergraph
+ * Iterates through subset of possible interpolation filters (currently
+ * only EIGHTTAP_REGULAR and EIGTHTAP_SMOOTH in both directions) and selects
+ * the one that gives lowest RD cost. RD cost is calculated using curvfit model
+ *
+ * \param[in] cpi Top-level encoder structure
+ * \param[in] x Pointer to structure holding all the
+ * data for the current macroblock
+ * \param[in] this_rdc Pointer to calculated RD Cost
+ * \param[in] mi_row Row index in 4x4 units
+ * \param[in] mi_col Column index in 4x4 units
+ * \param[in] tmp Pointer to a temporary buffer for
+ * prediction re-use
+ * \param[in] bsize Current block size
+ * \param[in] reuse_inter_pred Flag, indicating prediction re-use
+ * \param[out] this_mode_pred Pointer to store prediction buffer
+ * for prediction re-use
+ * \param[out] this_early_term Flag, indicating that transform can be
+ * skipped
+ * \param[in] use_model_yrd_large Flag, indicating special logic to handle
+ * large blocks
+ *
+ * \return Nothing is returned. Instead, calculated RD cost is placed to
+ * \c this_rdc and best filter is placed to \c mi->interp_filters. In case
+ * \c reuse_inter_pred flag is set, this function also ouputs
+ * \c this_mode_pred. Also \c this_early_temp is set if transform can be
+ * skipped
+ */
static void search_filter_ref(AV1_COMP *cpi, MACROBLOCK *x, RD_STATS *this_rdc,
int mi_row, int mi_col, PRED_BUFFER *tmp,
BLOCK_SIZE bsize, int reuse_inter_pred,
@@ -1548,6 +1601,39 @@
use_ref_frame[GOLDEN_FRAME] = use_golden_ref_frame;
}
+/*!\brief Estimates best intra mode for inter mode search
+ *
+ * \ingroup inter_mode_search
+ * \callgraph
+ * \callergraph
+ *
+ * Using heuristics based on best inter mode, block size, and other decides
+ * whether to check intra modes. If so, estimates and selects best intra mode
+ * from the reduced set of intra modes (max 4 intra modes checked)
+ *
+ * \param[in] cpi Top-level encoder structure
+ * \param[in] x Pointer to structure holding all the
+ * data for the current macroblock
+ * \param[in] bsize Current block size
+ * \param[in] use_modeled_non_rd_cost Flag, indicating usage of curvfit
+ * model for RD cost
+ * \param[in] best_early_term Flag, indicating that TX for the
+ * best inter mode was skipped
+ * \param[in] ref_cost_intra Cost of signalling intra mode
+ * \param[in] reuse_prediction Flag, indicating prediction re-use
+ * \param[in] orig_dst Original destination buffer
+ * \param[in] tmp_buffers Pointer to a temporary buffers for
+ * prediction re-use
+ * \param[out] this_mode_pred Pointer to store prediction buffer
+ * for prediction re-use
+ * \param[in] best_rdc Pointer to RD cost for the best
+ * selected intra mode
+ * \param[in] best_pickmode Pointer to a structure containing
+ * best mode picked so far
+ *
+ * \return Nothing is returned. Instead, calculated RD cost is placed to
+ * \c best_rdc and best selected mode is placed to \c best_pickmode
+ */
static void estimate_intra_mode(
AV1_COMP *cpi, MACROBLOCK *x, BLOCK_SIZE bsize, int use_modeled_non_rd_cost,
int best_early_term, unsigned int ref_cost_intra, int reuse_prediction,
