From 3e74cd919bcad54cf24ec2b1aaf04e6006c3239a Mon Sep 17 00:00:00 2001
From: jeffqjiangNew <142832361+jeffqjiangNew@users.noreply.github.com>
Date: Wed, 1 May 2024 08:29:26 -0400
Subject: [PATCH] AVC: Added support for picture adaptive frame-field (PICAFF)
 feature. (#325)

* * rocDecode/AVC: Added initial field picture decode support.
 - 7 conformance streams pass.

* * rocDecode/AVC: Minor change based on review comment.

* * rocDecode/AVC: Fixed an issue with getting the decoded frame buffer index for the second field.
 - 10 more field conformance streams now pass.

* * rocDecode/AVC: Added support for picture adaptive frame-field feature.
 - 10 more field conformance streams now pass.

* * rocDecode/AVC: Added a missing change during last merge.

[ROCm/rocdecode commit: d2b742ab4b819a0d9b6c0a64c0736a76a7f1f4e4]
---
 projects/rocdecode/src/parser/avc_parser.cpp | 16 ++++++++++++++--
 projects/rocdecode/src/parser/avc_parser.h   |  7 +++++--
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/projects/rocdecode/src/parser/avc_parser.cpp b/projects/rocdecode/src/parser/avc_parser.cpp
index 53cbb34a21..c7dda06e5f 100644
--- a/projects/rocdecode/src/parser/avc_parser.cpp
+++ b/projects/rocdecode/src/parser/avc_parser.cpp
@@ -39,6 +39,7 @@ AvcVideoParser::AvcVideoParser() {
     slice_info_list_.assign(INIT_SLICE_LIST_NUM, {0});
     slice_param_list_.assign(INIT_SLICE_LIST_NUM, {0});
     memset(&curr_pic_, 0, sizeof(AvcPicture));
+    field_pic_count_ = 0;
     second_field_ = 0;
     first_field_pic_idx_ = 0;
     InitDpb();
@@ -195,10 +196,12 @@ ParserResult AvcVideoParser::ParsePictureData(const uint8_t *p_stream, uint32_t
                     // Start decode process
                     if (num_slices_ == 0) {
                         if (p_slice_header->field_pic_flag) {
-                            second_field_ = pic_count_ & 1;
+                            second_field_ = field_pic_count_ & 1;
+                            field_pic_count_++;
                         } else {
                             second_field_ = 0;
                         }
+
                         // Use the data directly from demuxer without copying
                         pic_stream_data_ptr_ = pic_data_buffer_ptr_ + curr_start_code_offset_;
                         // Picture stream data size is calculated as the diff between the frame end and the first slice offset.
@@ -270,6 +273,7 @@ ParserResult AvcVideoParser::ParsePictureData(const uint8_t *p_stream, uint32_t
 
                 case kAvcNalTypeEnd_Of_Stream: {
                     pic_count_ = 0;
+                    field_pic_count_ = 0;
                     break;
                 }
 
@@ -2568,7 +2572,7 @@ ParserResult AvcVideoParser::CheckDpbAndOutput() {
 
 ParserResult AvcVideoParser::FindFreeBufInDpb() {
     int i;
-    if (!second_field_) {
+    if (curr_pic_.pic_structure == kFrame || !second_field_) {
         if (dpb_buffer_.dpb_fullness == dpb_buffer_.dpb_size) {
             if (BumpPicFromDpb() != PARSER_OK) {
                     return PARSER_FAIL;
@@ -2917,6 +2921,14 @@ ParserResult AvcVideoParser::InsertCurrPicIntoDpb() {
             } else if (curr_pic_.is_reference == kUsedForLongTerm) {
                 dpb_buffer_.num_long_term++;
             }
+
+            AvcSeqParameterSet *p_sps = &sps_list_[active_sps_id_];
+            if (p_sps->frame_mbs_only_flag == 0) { // picture adaptive frame-field (PICAFF)
+                dpb_buffer_.field_pic_list[i * 2] = curr_pic_;
+                dpb_buffer_.field_pic_list[i * 2].pic_structure = kTopField;
+                dpb_buffer_.field_pic_list[i * 2 + 1] = curr_pic_;
+                dpb_buffer_.field_pic_list[i * 2 + 1].pic_structure = kBottomField;
+            }
         }
         else {
             if (second_field_ == 0) {
diff --git a/projects/rocdecode/src/parser/avc_parser.h b/projects/rocdecode/src/parser/avc_parser.h
index 79964990fa..805338c2f0 100644
--- a/projects/rocdecode/src/parser/avc_parser.h
+++ b/projects/rocdecode/src/parser/avc_parser.h
@@ -128,10 +128,13 @@ protected:
     int curr_ref_pic_bottom_field_;
     int max_long_term_frame_idx_; // MaxLongTermFrameIdx
 
-    // DPB
-    AvcPicture curr_pic_;
+    // Field picture info
+    uint32_t field_pic_count_;
     int second_field_;
     int first_field_pic_idx_;
+
+    // DPB
+    AvcPicture curr_pic_;
     DecodedPictureBuffer dpb_buffer_;
 
     /*! \brief Function to notify decoder about video format change (new SPS) through callback