Add VP9 decoder support for external frame buffers

Added support for external frame buffers to libvpx's VP9 decoder.
If the external frame buffer functions are set then libvpx will
call the get function whenever it needs a new frame buffer to
decode a frame into. And it will call the release function
whenever there are no more references to that buffer.

Change-Id: Id2934d005f606af6e052fb6db0d5b7c02f567522

1 files changed, 32 insertions, 1 deletions

diff --git a/vpx/internal/vpx_codec_internal.h b/vpx/internal/vpx_codec_internal.h
index 0f42a1d20..51ca65e9f 100644
--- a/vpx/internal/vpx_codec_internal.h
+++ b/vpx/internal/vpx_codec_internal.h
@@ -59,7 +59,7 @@ extern "C" {
  * types, removing or reassigning enums, adding/removing/rearranging
  * fields to structures
  */
-#define VPX_CODEC_INTERNAL_ABI_VERSION (4) /**<\hideinitializer*/
+#define VPX_CODEC_INTERNAL_ABI_VERSION (5) /**<\hideinitializer*/
 
 typedef struct vpx_codec_alg_priv  vpx_codec_alg_priv_t;
 typedef struct vpx_codec_priv_enc_mr_cfg vpx_codec_priv_enc_mr_cfg_t;
@@ -218,6 +218,36 @@ typedef vpx_codec_err_t (*vpx_codec_decode_fn_t)(vpx_codec_alg_priv_t  *ctx,
 typedef vpx_image_t *(*vpx_codec_get_frame_fn_t)(vpx_codec_alg_priv_t *ctx,
                                                  vpx_codec_iter_t     *iter);
 
+/*!\brief Pass in external frame buffers for the decoder to use.
+ *
+ * Registers functions to be called when libvpx needs a frame buffer
+ * to decode the current frame and a function to be called when libvpx does
+ * not internally reference the frame buffer. This set function must
+ * be called before the first call to decode or libvpx will assume the
+ * default behavior of allocating frame buffers internally.
+ *
+ * \param[in] ctx          Pointer to this instance's context
+ * \param[in] cb_get       Pointer to the get callback function
+ * \param[in] cb_release   Pointer to the release callback function
+ * \param[in] cb_priv      Callback's private data
+ *
+ * \retval #VPX_CODEC_OK
+ *     External frame buffers will be used by libvpx.
+ * \retval #VPX_CODEC_INVALID_PARAM
+ *     One or more of the callbacks were NULL.
+ * \retval #VPX_CODEC_ERROR
+ *     Decoder context not initialized, or algorithm not capable of
+ *     using external frame buffers.
+ *
+ * \note
+ * When decoding VP9, the application may be required to pass in at least
+ * #VP9_MAXIMUM_REF_BUFFERS + #VPX_MAXIMUM_WORK_BUFFERS external frame
+ * buffers.
+ */
+typedef vpx_codec_err_t (*vpx_codec_set_fb_fn_t)(
+    vpx_codec_alg_priv_t *ctx,
+    vpx_get_frame_buffer_cb_fn_t cb_get,
+    vpx_release_frame_buffer_cb_fn_t cb_release, void *cb_priv);
 
 /*\brief eXternal Memory Allocation memory map get iterator
  *
@@ -308,6 +338,7 @@ struct vpx_codec_iface {
     vpx_codec_get_si_fn_t     get_si;      /**< \copydoc ::vpx_codec_get_si_fn_t */
     vpx_codec_decode_fn_t     decode;      /**< \copydoc ::vpx_codec_decode_fn_t */
     vpx_codec_get_frame_fn_t  get_frame;   /**< \copydoc ::vpx_codec_get_frame_fn_t */
+    vpx_codec_set_fb_fn_t     set_fb_fn;   /**< \copydoc ::vpx_codec_set_fb_fn_t */
   } dec;
   struct vpx_codec_enc_iface {
     vpx_codec_enc_cfg_map_t           *cfg_maps;      /**< \copydoc ::vpx_codec_enc_cfg_map_t */