VP9E_GET_ACTIVE_MAP API function.

This is useful when aq mode 3 (cyclic refresh) reactivates segments for refresh.

Change-Id: I3ad1d9410b899ede393d82bb8db14e2da4d84eca

vp9/encoder/vp9_encoder.c

@@ -183,6 +183,33 @@ int vp9_set_active_map(VP9_COMP* cpi,
   }
 }
 
+int vp9_get_active_map(VP9_COMP* cpi,
+                       unsigned char* new_map_16x16,
+                       int rows,
+                       int cols) {
+  if (rows == cpi->common.mb_rows && cols == cpi->common.mb_cols &&
+      new_map_16x16) {
+    unsigned char* const seg_map_8x8 = cpi->segmentation_map;
+    const int mi_rows = cpi->common.mi_rows;
+    const int mi_cols = cpi->common.mi_cols;
+    vpx_memset(new_map_16x16, !cpi->active_map.enabled, rows * cols);
+    if (cpi->active_map.enabled) {
+      int r, c;
+      for (r = 0; r < mi_rows; ++r) {
+        for (c = 0; c < mi_cols; ++c) {
+          // Cyclic refresh segments are considered active despite not having
+          // AM_SEGMENT_ID_ACTIVE
+          new_map_16x16[(r >> 1) * cols + (c >> 1)] |=
+              seg_map_8x8[r * mi_cols + c] != AM_SEGMENT_ID_INACTIVE;
+        }
+      }
+    }
+    return 0;
+  } else {
+    return -1;
+  }
+}
+
 void vp9_set_high_precision_mv(VP9_COMP *cpi, int allow_high_precision_mv) {
   MACROBLOCK *const mb = &cpi->td.mb;
   cpi->common.allow_high_precision_mv = allow_high_precision_mv;

vp9/encoder/vp9_encoder.h

@@ -508,6 +508,8 @@ int vp9_update_entropy(VP9_COMP *cpi, int update);
 
 int vp9_set_active_map(VP9_COMP *cpi, unsigned char *map, int rows, int cols);
 
+int vp9_get_active_map(VP9_COMP *cpi, unsigned char *map, int rows, int cols);
+
 int vp9_set_internal_size(VP9_COMP *cpi,
                           VPX_SCALING horiz_mode, VPX_SCALING vert_mode);
 

vp9/vp9_cx_iface.c

@@ -1260,6 +1260,21 @@ static vpx_codec_err_t ctrl_set_active_map(vpx_codec_alg_priv_t *ctx,
   }
 }
 
+static vpx_codec_err_t ctrl_get_active_map(vpx_codec_alg_priv_t *ctx,
+                                           va_list args) {
+  vpx_active_map_t *const map = va_arg(args, vpx_active_map_t *);
+
+  if (map) {
+    if (!vp9_get_active_map(ctx->cpi, map->active_map,
+                            (int)map->rows, (int)map->cols))
+      return VPX_CODEC_OK;
+    else
+      return VPX_CODEC_INVALID_PARAM;
+  } else {
+    return VPX_CODEC_INVALID_PARAM;
+  }
+}
+
 static vpx_codec_err_t ctrl_set_scale_mode(vpx_codec_alg_priv_t *ctx,
                                            va_list args) {
   vpx_scaling_mode_t *const mode = va_arg(args, vpx_scaling_mode_t *);
@@ -1417,6 +1432,7 @@ static vpx_codec_ctrl_fn_map_t encoder_ctrl_maps[] = {
 #if VPX_ENCODER_ABI_VERSION > (4 + VPX_CODEC_ABI_VERSION)
   {VP9E_GET_SVC_LAYER_ID,             ctrl_get_svc_layer_id},
 #endif
+  {VP9E_GET_ACTIVEMAP,                ctrl_get_active_map},
 
   { -1, NULL},
 };

vpx/vp8cx.h

@@ -508,6 +508,12 @@ enum vp8e_enc_control_id {
    * Supported in codecs: VP9
    */
   VP9E_SET_COLOR_SPACE,
+
+  /*!\brief Codec control function to get an Active map back from the encoder.
+   *
+   * Supported in codecs: VP9
+   */
+  VP9E_GET_ACTIVEMAP,
 };
 
 /*!\brief vpx 1-D scaling mode
@@ -691,6 +697,8 @@ VPX_CTRL_USE_TYPE(VP9E_SET_NOISE_SENSITIVITY,  unsigned int)
 VPX_CTRL_USE_TYPE(VP9E_SET_TUNE_CONTENT, int) /* vp9e_tune_content */
 
 VPX_CTRL_USE_TYPE(VP9E_SET_COLOR_SPACE, int)
+
+VPX_CTRL_USE_TYPE(VP9E_GET_ACTIVEMAP, vpx_active_map_t *)
 /*! @} - end defgroup vp8_encoder */
 #ifdef __cplusplus
 }  // extern "C"