vp9-svc: Add decoder control to decode up to x spatial layers.

Change-Id: I85536473b8722424785c84c5b5520960b4e5744a

2 files changed, 18 insertions, 0 deletions

diff --git a/vp9/vp9_dx_iface.c b/vp9/vp9_dx_iface.c
index 4a1ebbc8c..0a3e84a0d 100644
--- a/vp9/vp9_dx_iface.c
+++ b/vp9/vp9_dx_iface.c
@@ -553,6 +553,9 @@ static vpx_codec_err_t decoder_decode(vpx_codec_alg_priv_t *ctx,
                                    ctx->decrypt_cb, ctx->decrypt_state);
   if (res != VPX_CODEC_OK) return res;
 
+  if (ctx->svc_decoding && ctx->svc_spatial_layer < frame_count - 1)
+    frame_count = ctx->svc_spatial_layer + 1;
+
   if (ctx->frame_parallel_decode) {
     // Decode in frame parallel mode. When decoding in this mode, the frame
     // passed to the decoder must be either a normal frame or a superframe with
@@ -1001,6 +1004,16 @@ static vpx_codec_err_t ctrl_set_skip_loop_filter(vpx_codec_alg_priv_t *ctx,
   return VPX_CODEC_OK;
 }
 
+static vpx_codec_err_t ctrl_set_spatial_layer_svc(vpx_codec_alg_priv_t *ctx,
+                                                  va_list args) {
+  ctx->svc_decoding = 1;
+  ctx->svc_spatial_layer = va_arg(args, int);
+  if (ctx->svc_spatial_layer < 0)
+    return VPX_CODEC_INVALID_PARAM;
+  else
+    return VPX_CODEC_OK;
+}
+
 static vpx_codec_ctrl_fn_map_t decoder_ctrl_maps[] = {
   { VP8_COPY_REFERENCE, ctrl_copy_reference },
 
@@ -1011,6 +1024,7 @@ static vpx_codec_ctrl_fn_map_t decoder_ctrl_maps[] = {
   { VPXD_SET_DECRYPTOR, ctrl_set_decryptor },
   { VP9_SET_BYTE_ALIGNMENT, ctrl_set_byte_alignment },
   { VP9_SET_SKIP_LOOP_FILTER, ctrl_set_skip_loop_filter },
+  { VP9_DECODE_SVC_SPATIAL_LAYER, ctrl_set_spatial_layer_svc },
 
   // Getters
   { VP8D_GET_LAST_REF_UPDATES, ctrl_get_last_ref_updates },
diff --git a/vp9/vp9_dx_iface.h b/vp9/vp9_dx_iface.h
index cc3d51842..c1559599b 100644
--- a/vp9/vp9_dx_iface.h
+++ b/vp9/vp9_dx_iface.h
@@ -60,6 +60,10 @@ struct vpx_codec_alg_priv {
   void *ext_priv;  // Private data associated with the external frame buffers.
   vpx_get_frame_buffer_cb_fn_t get_ext_fb_cb;
   vpx_release_frame_buffer_cb_fn_t release_ext_fb_cb;
+
+  // Allow for decoding up to a given spatial layer for SVC stream.
+  int svc_decoding;
+  int svc_spatial_layer;
 };
 
 #endif  // VP9_VP9_DX_IFACE_H_