From 4fb2ba2861fffd8fca7dffbaf761d2bf2998df4f Mon Sep 17 00:00:00 2001
From: Marco <marpan@chromium.org>
Date: Tue, 27 Oct 2015 13:02:02 -0700
Subject: [PATCH] VP9-SVC: Allow frame dropping due to overshoot for spatial
 layers.

For 1 pass CBR mode.

Change-Id: I8bceb489a850ec26f05382eecb5c0c32a1bb8883
---
 vp9/encoder/vp9_encoder.c          | 7 +++++--
 vp9/encoder/vp9_ratectrl.c         | 5 +++--
 vp9/encoder/vp9_svc_layercontext.c | 4 ++++
 vp9/encoder/vp9_svc_layercontext.h | 1 +
 vpx/src/svc_encodeframe.c          | 1 +
 5 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/vp9/encoder/vp9_encoder.c b/vp9/encoder/vp9_encoder.c
index 72eafec40..8cc99cd74 100644
--- a/vp9/encoder/vp9_encoder.c
+++ b/vp9/encoder/vp9_encoder.c
@@ -3797,14 +3797,17 @@ static void encode_frame_to_data_rate(VP9_COMP *cpi,
   }
 
   // For 1 pass CBR, check if we are dropping this frame.
-  // Never drop on key frame.
+  // For spatial layers, for now only check for frame-dropping on first spatial
+  // layer, and if decision is to drop, we drop whole super-frame.
   if (oxcf->pass == 0 &&
       oxcf->rc_mode == VPX_CBR &&
       cm->frame_type != KEY_FRAME) {
-    if (vp9_rc_drop_frame(cpi)) {
+    if (vp9_rc_drop_frame(cpi) ||
+        (is_one_pass_cbr_svc(cpi) && cpi->svc.rc_drop_superframe == 1)) {
       vp9_rc_postencode_update_drop_frame(cpi);
       ++cm->current_video_frame;
       cpi->ext_refresh_frame_flags_pending = 0;
+      cpi->svc.rc_drop_superframe = 1;
       return;
     }
   }
diff --git a/vp9/encoder/vp9_ratectrl.c b/vp9/encoder/vp9_ratectrl.c
index d70068570..93cf2ccdd 100644
--- a/vp9/encoder/vp9_ratectrl.c
+++ b/vp9/encoder/vp9_ratectrl.c
@@ -370,8 +370,9 @@ void vp9_rc_init(const VP9EncoderConfig *oxcf, int pass, RATE_CONTROL *rc) {
 int vp9_rc_drop_frame(VP9_COMP *cpi) {
   const VP9EncoderConfig *oxcf = &cpi->oxcf;
   RATE_CONTROL *const rc = &cpi->rc;
-
-  if (!oxcf->drop_frames_water_mark) {
+  if (!oxcf->drop_frames_water_mark ||
+      (is_one_pass_cbr_svc(cpi) &&
+       cpi->svc.spatial_layer_id > cpi->svc.first_spatial_layer_to_encode)) {
     return 0;
   } else {
     if (rc->buffer_level < 0) {
diff --git a/vp9/encoder/vp9_svc_layercontext.c b/vp9/encoder/vp9_svc_layercontext.c
index 8a6818c86..1dfc45cf6 100644
--- a/vp9/encoder/vp9_svc_layercontext.c
+++ b/vp9/encoder/vp9_svc_layercontext.c
@@ -31,6 +31,7 @@ void vp9_init_layer_context(VP9_COMP *const cpi) {
   svc->spatial_layer_id = 0;
   svc->temporal_layer_id = 0;
   svc->first_spatial_layer_to_encode = 0;
+  svc->rc_drop_superframe = 0;
 
   if (cpi->oxcf.error_resilient_mode == 0 && cpi->oxcf.pass == 2) {
     if (vpx_realloc_frame_buffer(&cpi->svc.empty_frame.img,
@@ -568,6 +569,9 @@ int vp9_one_pass_cbr_svc_start_layer(VP9_COMP *const cpi) {
     }
   }
 
+  if (cpi->svc.spatial_layer_id == cpi->svc.first_spatial_layer_to_encode)
+    cpi->svc.rc_drop_superframe = 0;
+
   lc = &cpi->svc.layer_context[cpi->svc.spatial_layer_id *
                                cpi->svc.number_temporal_layers +
                                cpi->svc.temporal_layer_id];
diff --git a/vp9/encoder/vp9_svc_layercontext.h b/vp9/encoder/vp9_svc_layercontext.h
index 694b5abdc..5dbf9b418 100644
--- a/vp9/encoder/vp9_svc_layercontext.h
+++ b/vp9/encoder/vp9_svc_layercontext.h
@@ -56,6 +56,7 @@ typedef struct {
 
   int spatial_layer_to_encode;
   int first_spatial_layer_to_encode;
+  int rc_drop_superframe;
 
   // Workaround for multiple frame contexts
   enum {
diff --git a/vpx/src/svc_encodeframe.c b/vpx/src/svc_encodeframe.c
index ff600830e..ff7c10afc 100644
--- a/vpx/src/svc_encodeframe.c
+++ b/vpx/src/svc_encodeframe.c
@@ -485,6 +485,7 @@ vpx_codec_err_t vpx_svc_init(SvcContext *svc_ctx, vpx_codec_ctx_t *codec_ctx,
     enc_cfg->rc_buf_initial_sz = 500;
     enc_cfg->rc_buf_optimal_sz = 600;
     enc_cfg->rc_buf_sz = 1000;
+    enc_cfg->rc_dropframe_thresh = 0;
   }
 
   if (enc_cfg->g_error_resilient == 0 && si->use_multiple_frame_contexts == 0)