rocDecode: Added decode buffer pool implementation for AVC and HEVC. (#355)

* * rocDecode: Initial check in for decode buffer pool.

* * rocDecode: All 135 streams pass.

* * rocDecode: Fixed a build error in debug mode.

* * rocDecode/HEVC: Removed two workaround in HEVC DPB management, after decode buffer pool implementa
tion.
 - WR 1: Conditional bumping (when max_num_reorder_pics > 0) to avoid synchronous job submission in
C.5.2.3.
 - WR 2: Add two more buffers in DPB to avoid buffer over-writing.

* * rocDecode/HEVC: Added display delay feature.

* * rocDecode/HEVC: Fixed the -z option issue within the context of the new decode buffer pool implementation.

* * rocDecode/HEVC: Removed redundent code.

* * rocDecode/AVC: Added decode buffer pool implementation for AVC.

* * rocDecode: Added a few changes.
 - Added display delay feature to AVC.
 - Removed a workaround for AVC: AVC_MAX_DPB_FRAMES was increased to 18. Now it is back to 16.
 - Removed a workaround for AVC: increased DPB buffer size by 2. Now it is back to normal.
 - Code format changes for HEVC.

* * rocDecode/AVC: Fixed the -z option issue within the context of the new decode buffer pool implementation.

* * rocDecode: Merged OutputDecodedPictures() method to upper class RocVideoParser.

* * rocDecode: Code cleanup. No functional changes.

* * rocDecode: Made decode buffer pool size adaptive.
 - Removed the hard coded decode buffer pool size set in the decoder.
 - Exposed the display delay parameter from RocVideoDecoder class to the user.
 - Now the decoder buffer pool size is determined from the DPB buffer size and display delay parameter.

* * rocDecode: Several changes based on code review.
 - Merged decode and display use status into one parameter.
 - Removed the surface index from DecodeFrameBuffer, which is now implicitly referred by the array index.
 - Changed a function name for better clarity.

* * rocDecode: Added a comment.

[ROCm/rocdecode commit: 61c8661b9c]

projects/rocdecode/src/parser/roc_video_parser.h

@@ -78,6 +78,15 @@ typedef struct {
 #define INIT_SLICE_LIST_NUM 16 // initial slice information/parameter struct list size
 #define INIT_SEI_MESSAGE_COUNT 16  // initial SEI message count
 #define INIT_SEI_PAYLOAD_BUF_SIZE 1024 * 1024  // initial SEI payload buffer size, 1 MB
+#define DECODE_BUF_POOL_EXTENSION 2
+
+enum {
+    kNotUsed = 0,
+    kTopFieldUsedForDecode = 1,
+    kBottomFieldUsedForDecode = 1 << 1,
+    kFrameUsedForDecode = kTopFieldUsedForDecode | kBottomFieldUsedForDecode,
+    kFrameUsedForDisplay = 1 << 2
+} FrameBufUseStatus;
 
 /**
  * @brief Base class for video parsing
@@ -109,6 +118,21 @@ protected:
     uint32_t pic_height_;
     bool new_sps_activated_;
 
+    // Decoded buffer pool
+    typedef struct {
+        uint32_t use_status;    // refer to FrameBufUseStatus
+        uint32_t pic_order_cnt;
+    } DecodeFrameBuffer;
+    uint32_t dec_buf_pool_size_;        /* Number of decoded frame surfaces in the pool which are recycled. The size should be greater
+                                           than or equal to DPB size (normally greater to guarantee smooth operations). The value is
+                                           set to max_num_decode_surfaces from the decoder but parser checks and increases if needed. */
+    /* This array maps to VA surface array allocated at VA-API layer. A frame in the pool is identified by its index in the array, which
+     * is used to retrieve the VA surface Id.
+     */
+    std::vector<DecodeFrameBuffer> decode_buffer_pool_;
+    uint32_t num_output_pics_;  // number of pictures that are ready to be ouput
+    std::vector<uint32_t> output_pic_list_; // sorted output frame index to decode_buffer_pool_
+
     Rational frame_rate_;
 
     RocdecVideoFormat video_format_params_;
@@ -141,6 +165,17 @@ protected:
     uint32_t            sei_payload_buf_size_;
     uint32_t            sei_payload_size_;  // total SEI payload size of the current frame
 
+    /*! \brief Function to check the initially set (by decoder) decode buffer pool size and adjust if needed
+     *  \param dpb_size The DPB buffer size of the current sequence
+     */
+    void CheckAndAdjustDecBufPoolSize(int dpb_size);
+
+    /*! \brief Callback function to output decoded pictures from DPB for post-processing.
+     * \param [in] no_delay Indicator to override the display delay parameter wth no delay
+     * \return <tt>ParserResult</tt>
+     */
+    ParserResult OutputDecodedPictures(bool no_delay);
+
     /*! \brief Function to get the NAL Unit data
      * \return Returns OK if successful, else error code
      */
@@ -161,6 +196,10 @@ protected:
      * \return No return value
      */
     void ParseSeiMessage(uint8_t *nalu, size_t size);
+
+    /*! \brief Function to initialize the decoded buffer pool
+     */
+    void InitDecBufPool();
 };
 
 // helpers