Add SVC codec control to set frame flags and buffer indices.

Add SVC codec control to set the frame flags and buffer indices
for each spatial layer of the current (super)frame to be encoded.
This allows the application to set (and change on the fly) the
reference frame configuration for spatial layers.

Added an example layer pattern (spatial and temporal layers)
in vp9_spatial_svc_encoder for the bypass_mode using new control.

Change-Id: I05f941897cae13fb9275b939d11f93941cb73bee

1 files changed, 78 insertions, 0 deletions

diff --git a/examples/vp9_spatial_svc_encoder.c b/examples/vp9_spatial_svc_encoder.c
index 9f4191150..b26e98734 100644
--- a/examples/vp9_spatial_svc_encoder.c
+++ b/examples/vp9_spatial_svc_encoder.c
@@ -544,6 +544,59 @@ vpx_codec_err_t parse_superframe_index(const uint8_t *data,
 }
 #endif
 
+// Example pattern for spatial layers and 2 temporal layers used in the
+// bypass/flexible mode. The pattern corresponds to the pattern
+// VP9E_TEMPORAL_LAYERING_MODE_0101 (temporal_layering_mode == 2) used in
+// non-flexible mode.
+void set_frame_flags_bypass_mode(int sl, int tl, int num_spatial_layers,
+                                 int is_key_frame,
+                                 vpx_svc_ref_frame_config_t *ref_frame_config) {
+  for (sl = 0; sl < num_spatial_layers; ++sl) {
+    if (!tl) {
+      if (!sl) {
+        ref_frame_config->frame_flags[sl] = VP8_EFLAG_NO_REF_GF |
+                                            VP8_EFLAG_NO_REF_ARF |
+                                            VP8_EFLAG_NO_UPD_GF |
+                                            VP8_EFLAG_NO_UPD_ARF;
+      } else {
+        if (is_key_frame) {
+          ref_frame_config->frame_flags[sl] = VP8_EFLAG_NO_REF_LAST |
+                                              VP8_EFLAG_NO_REF_ARF |
+                                              VP8_EFLAG_NO_UPD_GF |
+                                              VP8_EFLAG_NO_UPD_ARF;
+        } else {
+        ref_frame_config->frame_flags[sl] = VP8_EFLAG_NO_REF_ARF |
+                                            VP8_EFLAG_NO_UPD_GF |
+                                            VP8_EFLAG_NO_UPD_ARF;
+        }
+      }
+    } else if (tl == 1) {
+      if (!sl) {
+        ref_frame_config->frame_flags[sl] = VP8_EFLAG_NO_REF_GF |
+                                            VP8_EFLAG_NO_REF_ARF |
+                                            VP8_EFLAG_NO_UPD_LAST |
+                                            VP8_EFLAG_NO_UPD_GF;
+      } else {
+        ref_frame_config->frame_flags[sl] = VP8_EFLAG_NO_REF_ARF |
+                                            VP8_EFLAG_NO_UPD_LAST |
+                                            VP8_EFLAG_NO_UPD_GF;
+      }
+    }
+    if (tl == 0) {
+      ref_frame_config->lst_fb_idx[sl] = sl;
+      if (sl)
+        ref_frame_config->gld_fb_idx[sl] = sl - 1;
+      else
+        ref_frame_config->gld_fb_idx[sl] = 0;
+      ref_frame_config->alt_fb_idx[sl] = 0;
+    } else if (tl == 1) {
+      ref_frame_config->lst_fb_idx[sl] = sl;
+      ref_frame_config->gld_fb_idx[sl] = num_spatial_layers + sl - 1;
+      ref_frame_config->alt_fb_idx[sl] = num_spatial_layers + sl;
+    }
+  }
+}
+
 int main(int argc, const char **argv) {
   AppInput app_input = {0};
   VpxVideoWriter *writer = NULL;
@@ -564,6 +617,7 @@ int main(int argc, const char **argv) {
   VpxVideoWriter *outfile[VPX_TS_MAX_LAYERS] = {NULL};
   struct RateControlStats rc;
   vpx_svc_layer_id_t layer_id;
+  vpx_svc_ref_frame_config_t ref_frame_config;
   int sl, tl;
   double sum_bitrate = 0.0;
   double sum_bitrate2 = 0.0;
@@ -653,6 +707,30 @@ int main(int argc, const char **argv) {
       end_of_stream = 1;
     }
 
+    // For BYPASS/FLEXIBLE mode, set the frame flags (reference and updates)
+    // and the buffer indices for each spatial layer of the current
+    // (super)frame to be encoded. The temporal layer_id for the current frame
+    // also needs to be set.
+    // TODO(marpan): Should rename the "VP9E_TEMPORAL_LAYERING_MODE_BYPASS"
+    // mode to "VP9E_LAYERING_MODE_BYPASS".
+    if (svc_ctx.temporal_layering_mode == VP9E_TEMPORAL_LAYERING_MODE_BYPASS) {
+      // Example for 2 temporal layers.
+      if (frame_cnt % 2 == 0)
+        layer_id.temporal_layer_id = 0;
+      else
+        layer_id.temporal_layer_id = 1;
+      // Note that we only set the temporal layer_id, since we are calling
+      // the encode for the whole superframe. The encoder will internally loop
+      // over all the spatial layers for the current superframe.
+      vpx_codec_control(&codec, VP9E_SET_SVC_LAYER_ID, &layer_id);
+      set_frame_flags_bypass_mode(sl, layer_id.temporal_layer_id,
+                                  svc_ctx.spatial_layers,
+                                  frame_cnt == 0,
+                                  &ref_frame_config);
+      vpx_codec_control(&codec, VP9E_SET_SVC_REF_FRAME_CONFIG,
+                        &ref_frame_config);
+    }
+
     vpx_usec_timer_start(&timer);
     res = vpx_svc_encode(&svc_ctx, &codec, (end_of_stream ? NULL : &raw),
                          pts, frame_duration, svc_ctx.speed >= 5 ?