ffmpeg software decoder implementation (#461)

* WIP: ffmpeg based software decoder

* minor update

* WIP: FFMpeg SW decoder support

* FFMpeg decoder working version

* working version without threading

* multithreading working with FFMpeg decoder

* moved ffmpeg decoder to separate folder

* updated changelog

* minor change

* resolved review comments

* resolved review comments

---------

Co-authored-by: Lakshmi Kumar <lakshmi.kumar@amd.com>

CHANGELOG.md

@@ -36,6 +36,8 @@ Full documentation for rocDecode is available at [https://rocm.docs.amd.com/proj
 * Clang is now the default CXX compiler.
 * The new minimum supported version of va-api is 1.16.
 * New build and runtime options have been added to the `rocDecode-setup.py` setup script.
+* Added FFMpeg based software decoding into utils.
+* Modified videodecode sample to allow FFMpeg based decoding
 
 ### Removed
 

CMakeLists.txt

@@ -171,6 +171,7 @@ if(HIP_FOUND AND Libva_FOUND)
   # install rocDecode samples -- {ROCM_PATH}/share/rocdecode
   install(DIRECTORY cmake DESTINATION ${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME} COMPONENT dev)
   install(DIRECTORY utils/rocvideodecode DESTINATION ${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}/utils COMPONENT dev)
+  install(DIRECTORY utils/ffmpegvideodecode DESTINATION ${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}/utils COMPONENT dev)
   install(FILES samples/videoDecode/CMakeLists.txt samples/videoDecode/README.md samples/videoDecode/videodecode.cpp DESTINATION ${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}/samples/videoDecode COMPONENT dev)
   install(FILES samples/videoDecodeMem/CMakeLists.txt samples/videoDecodeMem/README.md samples/videoDecodeMem/videodecodemem.cpp DESTINATION ${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}/samples/videoDecodeMem COMPONENT dev)
   install(FILES samples/videoDecodePerf/CMakeLists.txt samples/videoDecodePerf/README.md samples/videoDecodePerf/videodecodeperf.cpp DESTINATION ${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}/samples/videoDecodePerf COMPONENT dev)

api/rocdecode.h

@@ -107,6 +107,9 @@ typedef enum rocDecVideoSurfaceFormat_enum {
     rocDecVideoSurfaceFormat_YUV444 = 2,       /**< Planar YUV [Y plane followed by U and V planes] */
     rocDecVideoSurfaceFormat_YUV444_16Bit = 3, /**< 16 bit Planar YUV [Y plane followed by U and V planes].
                                                 Can be used for 10 bit(6LSB bits 0), 12 bit (4LSB bits 0) */
+    rocDecVideoSurfaceFormat_YUV420 = 4,       /**< Planar YUV [Y plane followed by U and V planes in 4:2:0 format] */
+    rocDecVideoSurfaceFormat_YUV420_16Bit = 5, /**< 16 bit Planar YUV [Y plane followed by U and V planes in ].
+                                                Can be used for 10 bit(LSB), 12 bit (LSB) */
 } rocDecVideoSurfaceFormat;
 
 /**************************************************************************************************************/

samples/videoDecode/CMakeLists.txt

@@ -72,10 +72,10 @@ if(HIP_FOUND AND FFMPEG_FOUND AND ROCDECODE_FOUND)
                         ${AVFORMAT_INCLUDE_DIR})
     set(LINK_LIBRARY_LIST ${LINK_LIBRARY_LIST} ${FFMPEG_LIBRARIES})
     # rocDecode and utils
-    include_directories (${ROCDECODE_INCLUDE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/.. ${CMAKE_CURRENT_SOURCE_DIR}/../../utils ${CMAKE_CURRENT_SOURCE_DIR}/../../utils/rocvideodecode)
+    include_directories (${ROCDECODE_INCLUDE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/.. ${CMAKE_CURRENT_SOURCE_DIR}/../../utils ${CMAKE_CURRENT_SOURCE_DIR}/../../utils/rocvideodecode ${CMAKE_CURRENT_SOURCE_DIR}/../../utils/ffmpegvideodecode)
     set(LINK_LIBRARY_LIST ${LINK_LIBRARY_LIST} ${ROCDECODE_LIBRARY})
     # sample app exe
-    list(APPEND SOURCES ${PROJECT_SOURCE_DIR} videodecode.cpp ${CMAKE_CURRENT_SOURCE_DIR}/../../utils/rocvideodecode/roc_video_dec.cpp)
+    list(APPEND SOURCES ${PROJECT_SOURCE_DIR} videodecode.cpp ${CMAKE_CURRENT_SOURCE_DIR}/../../utils/rocvideodecode/roc_video_dec.cpp ${CMAKE_CURRENT_SOURCE_DIR}/../../utils/ffmpegvideodecode/ffmpeg_video_dec.cpp)
     add_executable(${PROJECT_NAME} ${SOURCES})
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=gnu++17")
     target_link_libraries(${PROJECT_NAME} ${LINK_LIBRARY_LIST})

samples/videoDecode/videodecode.cpp

@@ -38,6 +38,7 @@ THE SOFTWARE.
 #endif
 #include "video_demuxer.h"
 #include "roc_video_dec.h"
+#include "ffmpeg_video_dec.h"
 #include "common.h"
 
 void ShowHelpAndExit(const char *option = NULL) {
@@ -45,6 +46,7 @@ void ShowHelpAndExit(const char *option = NULL) {
     << "-i Input File Path - required" << std::endl
     << "-o Output File Path - dumps output if requested; optional" << std::endl
     << "-d GPU device ID (0 for the first device, 1 for the second, etc.); optional; default: 0" << std::endl
+    << "-backend backend (0 for GPU, 1 CPU-FFMpeg, 2 CPU-FFMpeg No threading); optional; default: 0" << std::endl
     << "-f Number of decoded frames - specify the number of pictures to be decoded; optional" << std::endl
     << "-z force_zero_latency (force_zero_latency, Decoded frames will be flushed out for display immediately); optional;" << std::endl
     << "-disp_delay -specify the number of frames to be delayed for display; optional; default: 1" << std::endl
@@ -68,6 +70,7 @@ int main(int argc, char **argv) {
     int dump_output_frames = 0;
     int device_id = 0;
     int disp_delay = 1;
+    int backend = 0;
     bool b_force_zero_latency = false;     // false by default: enabling this option might affect decoding performance
     bool b_extract_sei_messages = false;
     bool b_generate_md5 = false;
@@ -106,6 +109,14 @@ int main(int argc, char **argv) {
             dump_output_frames = 1;
             continue;
         }
+        if (!strcmp(argv[i], "-backend")) {
+            if (++i == argc) {
+                ShowHelpAndExit("-backend");
+            }
+            backend = atoi(argv[i]);
+            continue;
+        }
+
         if (!strcmp(argv[i], "-d")) {
             if (++i == argc) {
                 ShowHelpAndExit("-d");
@@ -203,18 +214,30 @@ int main(int argc, char **argv) {
     try {
         std::size_t found_file = input_file_path.find_last_of('/');
         std::cout << "info: Input file: " << input_file_path.substr(found_file + 1) << std::endl;
+        RocVideoDecoder *viddec;
         VideoDemuxer demuxer(input_file_path.c_str());
         VideoSeekContext video_seek_ctx;
         rocDecVideoCodec rocdec_codec_id = AVCodec2RocDecVideoCodec(demuxer.GetCodecID());
-        RocVideoDecoder viddec(device_id, mem_type, rocdec_codec_id, b_force_zero_latency, p_crop_rect, b_extract_sei_messages, disp_delay);
-        if(!viddec.CodecSupported(device_id, rocdec_codec_id, demuxer.GetBitDepth())) {
-            std::cerr << "GPU doesn't support codec!" << std::endl;
+        if (!backend)   // gpu backend
+            viddec = new RocVideoDecoder(device_id, mem_type, rocdec_codec_id, b_force_zero_latency, p_crop_rect, b_extract_sei_messages, disp_delay);
+        else {
+            std::cout << "info: RocDecode is using CPU backend!" << std::endl;
+            bool use_threading = false;
+            if (mem_type == OUT_SURFACE_MEM_DEV_INTERNAL) mem_type = OUT_SURFACE_MEM_DEV_COPIED;    // mem_type internal is not supported in this mode
+            if (backend == 1) {
+                viddec = new FFMpegVideoDecoder(device_id, mem_type, rocdec_codec_id, b_force_zero_latency, p_crop_rect, b_extract_sei_messages, disp_delay);
+            } else
+                viddec = new FFMpegVideoDecoder(device_id, mem_type, rocdec_codec_id, b_force_zero_latency, p_crop_rect, b_extract_sei_messages, disp_delay, true);
+        }
+
+        if(!viddec->CodecSupported(device_id, rocdec_codec_id, demuxer.GetBitDepth())) {
+            std::cerr << "rocDecode doesn't support codec!" << std::endl;
             return 0;
         }        
         std::string device_name, gcn_arch_name;
         int pci_bus_id, pci_domain_id, pci_device_id;
 
-        viddec.GetDeviceinfo(device_name, gcn_arch_name, pci_bus_id, pci_domain_id, pci_device_id);
+        viddec->GetDeviceinfo(device_name, gcn_arch_name, pci_bus_id, pci_domain_id, pci_device_id);
         std::cout << "info: Using GPU device " << device_id << " - " << device_name << "[" << gcn_arch_name << "] on PCI bus " <<
         std::setfill('0') << std::setw(2) << std::right << std::hex << pci_bus_id << ":" << std::setfill('0') << std::setw(2) <<
         std::right << std::hex << pci_domain_id << "." << pci_device_id << std::dec << std::endl;
@@ -244,9 +267,9 @@ int main(int argc, char **argv) {
         reconfig_params.p_reconfig_user_struct = &reconfig_user_struct;
 
         if (b_generate_md5) {
-            viddec.InitMd5();
+            viddec->InitMd5();
         }
-        viddec.SetReconfigParams(&reconfig_params);
+        viddec->SetReconfigParams(&reconfig_params);
 
         do {
             auto start_time = std::chrono::high_resolution_clock::now();
@@ -275,22 +298,22 @@ int main(int argc, char **argv) {
             if (n_video_bytes == 0) {
                 pkg_flags |= ROCDEC_PKT_ENDOFSTREAM;
             }
-            n_frame_returned = viddec.DecodeFrame(pvideo, n_video_bytes, pkg_flags, pts, &decoded_pics);
+            n_frame_returned = viddec->DecodeFrame(pvideo, n_video_bytes, pkg_flags, pts, &decoded_pics);
 
-            if (!n_frame && !viddec.GetOutputSurfaceInfo(&surf_info)) {
+            if (!n_frame && !viddec->GetOutputSurfaceInfo(&surf_info)) {
                 std::cerr << "Error: Failed to get Output Surface Info!" << std::endl;
                 break;
             }
             for (int i = 0; i < n_frame_returned; i++) {
-                pframe = viddec.GetFrame(&pts);
+                pframe = viddec->GetFrame(&pts);
                 if (b_generate_md5) {
-                    viddec.UpdateMd5ForFrame(pframe, surf_info);
+                    viddec->UpdateMd5ForFrame(pframe, surf_info);
                 }
                 if (dump_output_frames && mem_type != OUT_SURFACE_MEM_NOT_MAPPED) {
-                    viddec.SaveFrameToFile(output_file_path, pframe, surf_info);
+                    viddec->SaveFrameToFile(output_file_path, pframe, surf_info);
                 }
                 // release frame
-                viddec.ReleaseFrame(pts);
+                viddec->ReleaseFrame(pts);
             }
             auto end_time = std::chrono::high_resolution_clock::now();
             auto time_per_decode = std::chrono::duration<double, std::milli>(end_time - start_time).count();
@@ -303,7 +326,7 @@ int main(int argc, char **argv) {
 
         } while (n_video_bytes);
         
-        n_frame += viddec.GetNumOfFlushedFrames();
+        n_frame += viddec->GetNumOfFlushedFrames();
         std::cout << "info: Total pictures decoded: " << n_pic_decoded << std::endl;
         std::cout << "info: Total frames output/displayed: " << n_frame << std::endl;
         if (!dump_output_frames) {
@@ -320,7 +343,7 @@ int main(int argc, char **argv) {
         }
         if (b_generate_md5) {
             uint8_t *digest;
-            viddec.FinalizeMd5(&digest);
+            viddec->FinalizeMd5(&digest);
             std::cout << "MD5 message digest: ";
             for (int i = 0; i < 16; i++) {
                 std::cout << std::setfill('0') << std::setw(2) << std::hex << static_cast<int>(digest[i]);

utils/ffmpegvideodecode/ffmpeg_video_dec.cpp

@@ -0,0 +1,857 @@
+/*
+Copyright (c) 2023 - 2024 Advanced Micro Devices, Inc. All rights reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+
+#include "ffmpeg_video_dec.h"
+
+/**
+ * @brief helper function for inferring AVCodecID from rocDecVideoCodec
+ * 
+ * @param rocdec_codec 
+ * @return AVCodecID 
+ */
+static inline AVCodecID RocDecVideoCodec2AVCodec(rocDecVideoCodec rocdec_codec) {
+    switch (rocdec_codec) {
+        case rocDecVideoCodec_MPEG1 : return AV_CODEC_ID_MPEG1VIDEO;
+        case rocDecVideoCodec_MPEG2 : return AV_CODEC_ID_MPEG2VIDEO;
+        case rocDecVideoCodec_MPEG4 : return AV_CODEC_ID_MPEG4;
+        case rocDecVideoCodec_AVC   : return AV_CODEC_ID_H264;
+        case rocDecVideoCodec_HEVC  : return AV_CODEC_ID_HEVC;
+        case rocDecVideoCodec_VP8   : return AV_CODEC_ID_VP8;
+        case rocDecVideoCodec_VP9   : return AV_CODEC_ID_VP9;
+        case rocDecVideoCodec_JPEG  : return AV_CODEC_ID_MJPEG;
+        case rocDecVideoCodec_AV1   : return AV_CODEC_ID_AV1;
+        default                     : return AV_CODEC_ID_NONE;
+    }
+}
+
+static inline float GetChromaWidthFactor(rocDecVideoSurfaceFormat surface_format) {
+    float factor = 0.5;
+    switch (surface_format) {
+    case rocDecVideoSurfaceFormat_NV12:
+    case rocDecVideoSurfaceFormat_P016:
+        factor = 1.0;
+        break;
+    case rocDecVideoSurfaceFormat_YUV444:
+    case rocDecVideoSurfaceFormat_YUV444_16Bit:
+        factor = 1.0;
+        break;
+    case rocDecVideoSurfaceFormat_YUV420:
+    case rocDecVideoSurfaceFormat_YUV420_16Bit:
+        factor = 0.5;
+        break;
+    }
+    return factor;
+};
+
+
+/**
+ * @brief helper function for inferring AVCodecID from rocDecVideoSurfaceFormat
+ * 
+ * @param rocdec_codec 
+ * @return AVCodecID 
+ */
+static inline rocDecVideoSurfaceFormat AVPixelFormat2rocDecVideoSurfaceFormat(AVPixelFormat av_pixel_format) {
+    switch (av_pixel_format) {
+        case AV_PIX_FMT_YUV420P : 
+        case AV_PIX_FMT_YUVJ420P : 
+            return rocDecVideoSurfaceFormat_YUV420;
+        case AV_PIX_FMT_YUV444P : 
+        case AV_PIX_FMT_YUVJ444P : 
+            return rocDecVideoSurfaceFormat_YUV444;
+        case AV_PIX_FMT_YUV420P10LE :
+        case AV_PIX_FMT_YUV420P12LE :
+            return rocDecVideoSurfaceFormat_YUV420_16Bit;
+        default :
+            std::cerr << "ERROR: " << av_get_pix_fmt_name(av_pixel_format) << " pixel_format is not supported!" << std::endl;          
+            return rocDecVideoSurfaceFormat_NV12;       // for sanity
+    }
+}
+
+FFMpegVideoDecoder::FFMpegVideoDecoder(int device_id, OutputSurfaceMemoryType out_mem_type, rocDecVideoCodec codec, bool force_zero_latency,
+              const Rect *p_crop_rect, bool extract_user_sei_Message, uint32_t disp_delay, bool no_multithreading, int max_width, int max_height, uint32_t clk_rate) :
+              RocVideoDecoder(device_id, out_mem_type, codec, force_zero_latency, p_crop_rect, extract_user_sei_Message, disp_delay, max_width, max_height, clk_rate), no_multithreading_(no_multithreading) {
+
+    if ((out_mem_type_ == OUT_SURFACE_MEM_DEV_INTERNAL) || (out_mem_type_ == OUT_SURFACE_MEM_NOT_MAPPED)) {
+        THROW("Output Memory Type is not supported");
+    }
+    if (rocdec_parser_) {
+        rocDecDestroyVideoParser(rocdec_parser_);       // need to do this here since it was already created in the base class
+        // create rocdec videoparser
+        RocdecParserParams parser_params = {};
+        parser_params.codec_type = codec_id_;
+        parser_params.max_num_decode_surfaces = 1; // let the parser to determine the decode buffer pool size
+        parser_params.clock_rate = clk_rate;
+        parser_params.max_display_delay = disp_delay_;
+        parser_params.user_data = this;
+        parser_params.pfn_sequence_callback = FFMpegHandleVideoSequenceProc;
+        parser_params.pfn_decode_picture = FFMpegHandlePictureDecodeProc;
+        parser_params.pfn_display_picture = FFMpegHandlePictureDisplayProc;
+        parser_params.pfn_get_sei_msg = b_extract_sei_message_ ? RocVideoDecoder::HandleSEIMessagesProc : NULL;
+        ROCDEC_API_CALL(rocDecCreateVideoParser(&rocdec_parser_, &parser_params));
+    }
+    if (!no_multithreading_) {
+        // start the FFMpeg decoding thread
+        ffmpeg_decoder_thread_ = new std::thread(&FFMpegVideoDecoder::DecodeThread, this);
+        if (!ffmpeg_decoder_thread_) {
+            THROW("FFMpegVideoDecoder create thread failed");
+        }
+    }
+}
+
+
+FFMpegVideoDecoder::~FFMpegVideoDecoder() {
+
+    std::lock_guard<std::mutex> lock(mtx_vp_frame_);
+    for (auto &p_frame : vp_frames_ffmpeg_) {
+        if (p_frame.frame_ptr) {
+            if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) {
+                hipError_t hip_status = hipFree(p_frame.frame_ptr);
+                if (hip_status != hipSuccess) {
+                    std::cerr << "ERROR: hipFree failed! (" << hip_status << ")" << std::endl;
+                }
+            }
+        }
+    }
+
+    // release frame_q
+    while (!dec_frames_.empty()) {
+        av_frame_free(&dec_frames_.back());
+        dec_frames_.pop_back();
+    }
+    // free av_packet_data_
+    while (!av_packet_data_.empty()) {
+        std::pair<uint8_t *, int> *packet_data = &av_packet_data_.back();
+        av_freep(&packet_data->first);
+        av_packet_data_.pop_back();
+    }
+
+    //release av_packets
+    while (!av_packets_.empty()) {
+        av_packet_free(&av_packets_.back());
+        av_packets_.pop_back();
+    }
+
+    if (dec_context_) {
+        avcodec_free_context(&dec_context_);
+    }
+}
+
+/* Return value from HandleVideoSequence() are interpreted as   :
+*  0: fail, 1: succeeded, > 1: override dpb size of parser (set by CUVIDPARSERPARAMS::max_num_decode_surfaces while creating parser)
+*/
+int FFMpegVideoDecoder::HandleVideoSequence(RocdecVideoFormat *p_video_format) {
+    if (p_video_format == nullptr) {
+        ROCDEC_THROW("Rocdec:: Invalid video format in HandleVideoSequence: ", ROCDEC_INVALID_PARAMETER);
+        return 0;
+    }
+    auto start_time = StartTimer();
+    input_video_info_str_.str("");
+    input_video_info_str_.clear();
+    input_video_info_str_ << "Input Video Information" << std::endl
+        << "\tCodec        : " << GetCodecFmtName(p_video_format->codec) << std::endl;
+        if (p_video_format->frame_rate.numerator && p_video_format->frame_rate.denominator) {
+            input_video_info_str_ << "\tFrame rate   : " << p_video_format->frame_rate.numerator << "/" << p_video_format->frame_rate.denominator << " = " << 1.0 * p_video_format->frame_rate.numerator / p_video_format->frame_rate.denominator << " fps" << std::endl;
+        }
+    input_video_info_str_ << "\tSequence     : " << (p_video_format->progressive_sequence ? "Progressive" : "Interlaced") << std::endl
+        << "\tCoded size   : [" << p_video_format->coded_width << ", " << p_video_format->coded_height << "]" << std::endl
+        << "\tDisplay area : [" << p_video_format->display_area.left << ", " << p_video_format->display_area.top << ", "
+            << p_video_format->display_area.right << ", " << p_video_format->display_area.bottom << "]" << std::endl
+        << "\tBit depth    : " << p_video_format->bit_depth_luma_minus8 + 8
+    ;
+    input_video_info_str_ << std::endl;
+
+    int num_decode_surfaces = p_video_format->min_num_decode_surfaces;
+
+    // check if the codec is supported in FFMpeg
+    // Initialize FFMpeg and find the decoder for codec
+    if (!decoder_) decoder_ = avcodec_find_decoder(RocDecVideoCodec2AVCodec(p_video_format->codec));
+    if(!decoder_) {
+        ROCDEC_THROW("rocDecode<FFMpeg>:: Codec not supported by FFMpeg ", ROCDEC_NOT_SUPPORTED);
+        return 0;
+    }
+    if (!dec_context_) {
+        dec_context_ = avcodec_alloc_context3(decoder_);        //alloc dec_context_
+        if (!dec_context_) {
+            THROW("Could not allocate video codec context");
+        }
+        // open the codec
+        if (avcodec_open2(dec_context_, decoder_, NULL) < 0) {
+            THROW("Could not open codec");
+        }
+        // get the output pixel format from dec_context_
+        decoder_pixel_format_ = (dec_context_->pix_fmt == AV_PIX_FMT_NONE) ? AV_PIX_FMT_YUV420P : dec_context_->pix_fmt;
+        dec_context_->thread_count = 4;
+        dec_context_->thread_type = FF_THREAD_FRAME;
+
+    }
+    // allocate av_frame buffer pool for number of surfaces
+    if (dec_frames_.empty()) {
+        for (int i = 0; i < num_decode_surfaces; i++) {
+            AVFrame *p_frame = av_frame_alloc();
+            dec_frames_.push_back(p_frame);
+        }
+        av_frame_cnt_ = 0;
+    }
+    if (av_packet_data_.empty()) {
+        for (int i = 0; i < num_decode_surfaces; i++) {
+            uint8_t *pkt_data = static_cast<uint8_t *> (av_malloc(MAX_AV_PACKET_DATA_SIZE));
+            av_packet_data_.push_back(std::make_pair(pkt_data, MAX_AV_PACKET_DATA_SIZE));
+        }
+    }
+
+    // allocate av_packets_ for decoding
+    if (av_packets_.empty()) {
+        for (int i = 0; i < num_decode_surfaces; i++) {
+            AVPacket *pkt = av_packet_alloc();
+            pkt->data = static_cast<uint8_t *> (av_packet_data_[i].first);
+            pkt->size = av_packet_data_[i].second;
+            av_packets_.push_back(pkt);
+        }
+    }
+
+    if (curr_video_format_ptr_ == nullptr) {
+        curr_video_format_ptr_ = new RocdecVideoFormat();
+    }
+    // store current video format: this is required to call reconfigure from application in case of random seek
+    if (curr_video_format_ptr_) memcpy(curr_video_format_ptr_, p_video_format, sizeof(RocdecVideoFormat));
+
+    if (coded_width_ && coded_height_) {
+        end_of_stream_ = false;
+        // rocdecCreateDecoder() has been called before, and now there's possible config change
+        return ReconfigureDecoder(p_video_format);
+    }
+    // e_codec has been set in the constructor (for parser). Here it's set again for potential correction
+    codec_id_ = p_video_format->codec;
+    video_chroma_format_ = p_video_format->chroma_format;
+    bitdepth_minus_8_ = p_video_format->bit_depth_luma_minus8;
+    byte_per_pixel_ = bitdepth_minus_8_ > 0 ? 2 : 1;
+
+    // convert AVPixelFormat to rocDecVideoChromaFormat
+    video_surface_format_ = AVPixelFormat2rocDecVideoSurfaceFormat(decoder_pixel_format_);
+    coded_width_ = p_video_format->coded_width;
+    coded_height_ = p_video_format->coded_height;
+    disp_rect_.top = p_video_format->display_area.top;
+    disp_rect_.bottom = p_video_format->display_area.bottom;
+    disp_rect_.left = p_video_format->display_area.left;
+    disp_rect_.right = p_video_format->display_area.right;
+    disp_width_ = p_video_format->display_area.right - p_video_format->display_area.left;
+    disp_height_ = p_video_format->display_area.bottom - p_video_format->display_area.top;
+
+    // AV1 has max width/height of sequence in sequence header
+    if (codec_id_ == rocDecVideoCodec_AV1 && p_video_format->seqhdr_data_length > 0) {
+        // dont overwrite if it is already set from cmdline or reconfig.txt
+        if (!(max_width_ > p_video_format->coded_width || max_height_ > p_video_format->coded_height)) {
+            RocdecVideoFormatEx *vidFormatEx = (RocdecVideoFormatEx *)p_video_format;
+            max_width_ = vidFormatEx->max_width;
+            max_height_ = vidFormatEx->max_height;
+        }
+    }
+    if (max_width_ < static_cast<int>(p_video_format->coded_width))
+        max_width_ = p_video_format->coded_width;
+    if (max_height_ < static_cast<int>(p_video_format->coded_height))
+        max_height_ = p_video_format->coded_height;
+
+    if (!(crop_rect_.right && crop_rect_.bottom)) {
+        target_width_ = (disp_width_ + 1) & ~1;
+        target_height_ = (disp_height_ + 1) & ~1;
+    } else {
+        target_width_ = (crop_rect_.right - crop_rect_.left + 1) & ~1;
+        target_height_ = (crop_rect_.bottom - crop_rect_.top + 1) & ~1;
+    }
+
+    chroma_height_ = static_cast<int>(ceil(target_height_ * GetChromaHeightFactor(video_surface_format_)));
+    chroma_width_ = static_cast<int>(ceil(target_width_ * GetChromaWidthFactor(video_surface_format_)));
+    num_chroma_planes_ = GetChromaPlaneCount(video_surface_format_);
+    if (video_chroma_format_ == rocDecVideoChromaFormat_Monochrome) num_chroma_planes_ = 0;
+    surface_stride_ = target_width_ * byte_per_pixel_;   
+    chroma_vstride_ = static_cast<int>(ceil(surface_vstride_ * GetChromaHeightFactor(video_surface_format_)));
+    // fill output_surface_info_
+    output_surface_info_.output_width = target_width_;
+    output_surface_info_.output_height = target_height_;
+    output_surface_info_.output_pitch  = surface_stride_;
+    output_surface_info_.output_vstride = target_height_;
+    output_surface_info_.bit_depth = bitdepth_minus_8_ + 8;
+    output_surface_info_.bytes_per_pixel = byte_per_pixel_;
+    output_surface_info_.surface_format = video_surface_format_;
+    output_surface_info_.num_chroma_planes = num_chroma_planes_;
+    if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) {
+        output_surface_info_.output_surface_size_in_bytes = GetFrameSize();
+        output_surface_info_.mem_type = OUT_SURFACE_MEM_DEV_COPIED;
+    } else if (out_mem_type_ == OUT_SURFACE_MEM_HOST_COPIED){
+        output_surface_info_.output_surface_size_in_bytes = GetFrameSize();
+        output_surface_info_.mem_type = OUT_SURFACE_MEM_HOST_COPIED;
+    }
+    input_video_info_str_ << "Video Decoding Params:" << std::endl
+        << "\tNum Surfaces : " << num_decode_surfaces << std::endl
+        << "\tCrop         : [" << disp_rect_.left << ", " << disp_rect_.top << ", "
+        << disp_rect_.right << ", " << disp_rect_.bottom << "]" << std::endl
+        << "\tResize       : " << target_width_ << "x" << target_height_ << std::endl
+    ;
+    input_video_info_str_ << std::endl;
+    std::cout << input_video_info_str_.str();
+
+    double elapsed_time = StopTimer(start_time);
+    AddDecoderSessionOverHead(std::this_thread::get_id(), elapsed_time);
+    return num_decode_surfaces;
+}
+
+/**
+ * @brief function to reconfigure decoder if there is a change in sequence params.
+ *
+ * @param p_video_format
+ * @return int 1: success 0: fail
+ */
+int FFMpegVideoDecoder::ReconfigureDecoder(RocdecVideoFormat *p_video_format) {
+    if (p_video_format->codec != codec_id_) {
+        ROCDEC_THROW("Reconfigure Not supported for codec change", ROCDEC_NOT_SUPPORTED);
+        return 0;
+    }
+    if (p_video_format->chroma_format != video_chroma_format_) {
+        ROCDEC_THROW("Reconfigure Not supported for chroma format change", ROCDEC_NOT_SUPPORTED);
+        return 0;
+    }
+    if (p_video_format->bit_depth_luma_minus8 != bitdepth_minus_8_){
+        ROCDEC_THROW("Reconfigure Not supported for bit depth change", ROCDEC_NOT_SUPPORTED);
+        return 0;
+    }
+    bool is_decode_res_changed = !(p_video_format->coded_width == coded_width_ && p_video_format->coded_height == coded_height_);
+    bool is_display_rect_changed = !(p_video_format->display_area.bottom == disp_rect_.bottom &&
+                                     p_video_format->display_area.top == disp_rect_.top &&
+                                     p_video_format->display_area.left == disp_rect_.left &&
+                                     p_video_format->display_area.right == disp_rect_.right);
+
+    if (!is_decode_res_changed && !is_display_rect_changed && !b_force_recofig_flush_) {
+        return 1;
+    }
+
+    // Flush and clear internal frame store to reconfigure when either coded size or display size has changed.
+    if (p_reconfig_params_ && p_reconfig_params_->p_fn_reconfigure_flush) 
+        num_frames_flushed_during_reconfig_ += p_reconfig_params_->p_fn_reconfigure_flush(this, p_reconfig_params_->reconfig_flush_mode, static_cast<void *>(p_reconfig_params_->p_reconfig_user_struct));
+    // clear the existing output buffers of different size
+    // note that app lose the remaining frames in the vp_frames in case application didn't set p_fn_reconfigure_flush_ callback
+    std::lock_guard<std::mutex> lock(mtx_vp_frame_);
+    while(!vp_frames_ffmpeg_.empty()) {
+        DecFrameBufferFFMpeg *p_frame = &vp_frames_ffmpeg_.back();
+        // pop decoded frame
+        vp_frames_ffmpeg_.pop_back();
+        if (p_frame->frame_ptr) {
+            if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) {
+                hipError_t hip_status = hipFree(p_frame->frame_ptr);
+                if (hip_status != hipSuccess) std::cerr << "ERROR: hipFree failed! (" << hip_status << ")" << std::endl;
+            }
+        }
+        // release associated av_frame
+        if (p_frame->av_frame_ptr) {
+            av_frame_free(&p_frame->av_frame_ptr);
+        }
+    }
+    output_frame_cnt_ = 0;     // reset frame_count
+    if (is_decode_res_changed) {
+        coded_width_ = p_video_format->coded_width;
+        coded_height_ = p_video_format->coded_height;
+    }
+    if (is_display_rect_changed) {
+        disp_rect_.left = p_video_format->display_area.left;
+        disp_rect_.right = p_video_format->display_area.right;
+        disp_rect_.top = p_video_format->display_area.top;
+        disp_rect_.bottom = p_video_format->display_area.bottom;
+        disp_width_ = p_video_format->display_area.right - p_video_format->display_area.left;
+        disp_height_ = p_video_format->display_area.bottom - p_video_format->display_area.top;
+
+        if (!(crop_rect_.right && crop_rect_.bottom)) {
+            target_width_ = (disp_width_ + 1) & ~1;
+            target_height_ = (disp_height_ + 1) & ~1;
+        } else {
+            target_width_ = (crop_rect_.right - crop_rect_.left + 1) & ~1;
+            target_height_ = (crop_rect_.bottom - crop_rect_.top + 1) & ~1;
+        }
+    }
+
+    surface_stride_ = target_width_ * byte_per_pixel_;
+    chroma_height_ = static_cast<int>(std::ceil(target_height_ * GetChromaHeightFactor(video_surface_format_)));
+    chroma_width_ = static_cast<int>(ceil(target_width_ * GetChromaWidthFactor(video_surface_format_)));
+    num_chroma_planes_ = GetChromaPlaneCount(video_surface_format_);
+    if (p_video_format->chroma_format == rocDecVideoChromaFormat_Monochrome) num_chroma_planes_ = 0;
+    chroma_vstride_ = static_cast<int>(std::ceil(surface_vstride_ * GetChromaHeightFactor(video_surface_format_)));
+    // Fill output_surface_info_
+    output_surface_info_.output_width = target_width_;
+    output_surface_info_.output_height = target_height_;
+    output_surface_info_.output_pitch  = surface_stride_;
+    output_surface_info_.output_vstride = (out_mem_type_ == OUT_SURFACE_MEM_DEV_INTERNAL) ? surface_vstride_ : target_height_;
+    output_surface_info_.bit_depth = bitdepth_minus_8_ + 8;
+    output_surface_info_.bytes_per_pixel = byte_per_pixel_;
+    output_surface_info_.surface_format = video_surface_format_;
+    output_surface_info_.num_chroma_planes = num_chroma_planes_;
+    if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) {
+        output_surface_info_.output_surface_size_in_bytes = GetFrameSize();
+        output_surface_info_.mem_type = OUT_SURFACE_MEM_DEV_COPIED;
+    } else if (out_mem_type_ == OUT_SURFACE_MEM_HOST_COPIED) {
+        output_surface_info_.output_surface_size_in_bytes = GetFrameSize();
+        output_surface_info_.mem_type = OUT_SURFACE_MEM_HOST_COPIED;
+    }
+
+    // If the coded_width or coded_height hasn't changed but display resolution has changed, then need to update width and height for
+    // correct output with cropping. There is no need to reconfigure the decoder.
+    if (!is_decode_res_changed && is_display_rect_changed) {
+        return 1;
+    }
+
+    input_video_info_str_.str("");
+    input_video_info_str_.clear();
+    input_video_info_str_ << "Input Video Resolution Changed:" << std::endl
+        << "\tCoded size   : [" << p_video_format->coded_width << ", " << p_video_format->coded_height << "]" << std::endl
+        << "\tDisplay area : [" << p_video_format->display_area.left << ", " << p_video_format->display_area.top << ", "
+            << p_video_format->display_area.right << ", " << p_video_format->display_area.bottom << "]" << std::endl;
+    input_video_info_str_ << std::endl;
+    is_decoder_reconfigured_ = true;
+    return 1;
+}
+
+/**
+ * @brief 
+ * 
+ * @param pPicParams 
+ * @return int 1: success 0: fail
+ */
+int FFMpegVideoDecoder::HandlePictureDecode(RocdecPicParams *pPicParams) {
+    AVPacket *av_pkt = av_packets_[av_pkt_cnt_];
+    std::pair<uint8_t *, int> *packet_data = &av_packet_data_[av_pkt_cnt_];
+    if (last_packet_.payload_size > packet_data->second) {
+        void *new_pkt_data = av_realloc(av_pkt->data, (last_packet_.payload_size + MAX_AV_PACKET_DATA_SIZE));  // add more to avoid frequence reallocation
+        if (!new_pkt_data) {
+            std::cerr << "ERROR: couldn't allocate packet data" << std::endl;
+        }
+        packet_data->first   = static_cast<uint8_t *>(new_pkt_data);
+        packet_data->second  = (last_packet_.payload_size + MAX_AV_PACKET_DATA_SIZE);
+        av_pkt->data = packet_data->first;
+    }
+    memcpy(av_pkt->data, last_packet_.payload, last_packet_.payload_size);
+    av_pkt->size = last_packet_.payload_size;
+    av_pkt->flags = 0;
+    av_pkt->pts = last_packet_.pts;
+
+    if (no_multithreading_) {
+        DecodeAvFrame(av_pkt, dec_frames_[av_frame_cnt_]);
+    } else {
+        //push packet into packet q for decoding
+        PushPacket(av_pkt);
+    }
+    av_pkt_cnt_ = (av_pkt_cnt_ + 1) % av_packets_.size();
+    if (!av_pkt->data || !av_pkt->size) {
+        end_of_stream_ = true;
+    }
+
+    return 1;
+}
+
+/**
+ * @brief function to handle display picture
+ * 
+ * @param pDispInfo 
+ * @return int 0:fail 1: success
+ */
+int FFMpegVideoDecoder::HandlePictureDisplay(RocdecParserDispInfo *pDispInfo) {
+    // check if we reached eos here. This is a hack since HandlePictureDecode won't be called at the end_of_sequece. 
+    // so we need to flush FFMpeg decoder when we have received the lastpacket with 0 bytes
+    if (!last_packet_.payload_size && !end_of_stream_) {
+        AVPacket pkt = { 0 };
+        if (no_multithreading_) {
+            DecodeAvFrame(&pkt, dec_frames_[av_frame_cnt_]);
+        } else {
+            //push packet into packet q for decoding
+            PushPacket(&pkt);
+        }
+    }
+
+    if (b_extract_sei_message_) {
+        if (sei_message_display_q_[pDispInfo->picture_index].sei_data) {
+            // Write SEI Message
+            uint8_t *sei_buffer = static_cast<uint8_t *>(sei_message_display_q_[pDispInfo->picture_index].sei_data);
+            uint32_t sei_num_messages = sei_message_display_q_[pDispInfo->picture_index].sei_message_count;
+            RocdecSeiMessage *sei_message = sei_message_display_q_[pDispInfo->picture_index].sei_message;
+            if (fp_sei_) {
+                for (uint32_t i = 0; i < sei_num_messages; i++) {
+                    if (codec_id_ == rocDecVideoCodec_AVC || rocDecVideoCodec_HEVC) {
+                        switch (sei_message[i].sei_message_type) {
+                            case SEI_TYPE_TIME_CODE: {
+                                //todo:: check if we need to write timecode
+                            }
+                            break;
+                            case SEI_TYPE_USER_DATA_UNREGISTERED: {
+                                fwrite(sei_buffer, sei_message[i].sei_message_size, 1, fp_sei_);
+                            }
+                            break;
+                        }
+                    }
+                    if (codec_id_ == rocDecVideoCodec_AV1) {
+                        fwrite(sei_buffer, sei_message[i].sei_message_size, 1, fp_sei_);
+                    }    
+                    sei_buffer += sei_message[i].sei_message_size;
+                }
+            }
+            free(sei_message_display_q_[pDispInfo->picture_index].sei_data);
+            sei_message_display_q_[pDispInfo->picture_index].sei_data = NULL; // to avoid double free
+            free(sei_message_display_q_[pDispInfo->picture_index].sei_message);
+            sei_message_display_q_[pDispInfo->picture_index].sei_message = NULL; // to avoid double free
+        }
+    }
+    // vp_frames_ffmpeg_.size() is empty, wait for decoding to finish
+    // this will happen during PopFrame()
+    AVFrame *p_av_frame;
+    if (no_multithreading_) {
+        p_av_frame = av_frame_q_.front();
+        av_frame_q_.pop();
+    } else {
+        p_av_frame = PopFrame();
+    }
+
+    if (p_av_frame == nullptr) {
+        std::cerr << "Invalid avframe decode output" << std::endl;
+        return 0;
+    }
+    void* src_ptr[3] = { 0 };
+    int32_t src_pitch[3] = { 0 };
+    src_ptr[0] = p_av_frame->data[0];    
+    src_ptr[1] = p_av_frame->data[1];
+    src_ptr[2] = p_av_frame->data[2];
+    src_pitch[0] = p_av_frame->linesize[0];
+    src_pitch[1] = p_av_frame->linesize[1];
+    src_pitch[2] = p_av_frame->linesize[2];
+
+    // copy the decoded surface info device or host
+    uint8_t *p_dec_frame = nullptr;
+    {
+        std::lock_guard<std::mutex> lock(mtx_vp_frame_);
+        // if not enough frames in stock, allocate
+        if (++output_frame_cnt_ > vp_frames_ffmpeg_.size()) {
+            num_alloced_frames_++;
+            DecFrameBufferFFMpeg dec_frame = { 0 };
+            if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) {
+                // allocate device memory
+                HIP_API_CALL(hipMalloc((void **)&dec_frame.frame_ptr, GetFrameSize()));
+            } else {
+                dec_frame.frame_ptr = new uint8_t[GetFrameSize()];
+            }
+
+            dec_frame.av_frame_ptr = p_av_frame;
+            dec_frame.pts = pDispInfo->pts;
+            dec_frame.picture_index = pDispInfo->picture_index;
+            vp_frames_ffmpeg_.push_back(dec_frame);
+        }
+        p_dec_frame = vp_frames_ffmpeg_[output_frame_cnt_ - 1].frame_ptr;
+    }
+
+    // Copy luma data
+    int dst_pitch = disp_width_ * byte_per_pixel_;
+    uint8_t *p_src_ptr_y = static_cast<uint8_t *>(src_ptr[0]) + (disp_rect_.top + crop_rect_.top) * src_pitch[0] + (disp_rect_.left + crop_rect_.left) * byte_per_pixel_;
+    uint8_t *p_frame_y = p_dec_frame;
+    if (!p_frame_y && !p_src_ptr_y) {
+        std::cerr << "HandlePictureDisplay: Invalid Memory address for src/dst" << std::endl;
+        return 0;
+    }
+    if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) {
+        if (src_pitch[0] == dst_pitch) {
+            int luma_size = src_pitch[0] * disp_height_;
+            HIP_API_CALL(hipMemcpyHtoDAsync(p_frame_y, p_src_ptr_y, luma_size, hip_stream_));
+        } else {
+            // use 2d copy to copy an ROI
+            HIP_API_CALL(hipMemcpy2DAsync(p_frame_y, dst_pitch, p_src_ptr_y, src_pitch[0], dst_pitch, disp_height_, hipMemcpyHostToDevice, hip_stream_));
+        }
+    } else {
+        if (src_pitch[0] == dst_pitch) {
+            int luma_size = src_pitch[0] * disp_height_;
+            memcpy(p_frame_y, p_src_ptr_y, luma_size);
+        } else {
+            for (int i = 0; i < disp_height_; i++) {
+                memcpy(p_dec_frame, p_src_ptr_y, dst_pitch);
+                p_frame_y += dst_pitch;
+                p_src_ptr_y += src_pitch[0];
+            }
+        }
+    }
+    // Copy chroma plane ( )
+    // rocDec output gives pointer to luma and chroma pointers seperated for the decoded frame
+    uint8_t *p_frame_uv = p_dec_frame + dst_pitch * disp_height_;
+    uint8_t *p_src_ptr_uv = static_cast<uint8_t *>(src_ptr[1]) + ((disp_rect_.top + crop_rect_.top) >> 1) * src_pitch[1] + ((disp_rect_.left + crop_rect_.left)>>1) * byte_per_pixel_ ;
+    dst_pitch = chroma_width_ *  byte_per_pixel_;          
+    if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) {
+        if (src_pitch[1] == dst_pitch) {
+            int chroma_size = chroma_height_ * dst_pitch;
+            HIP_API_CALL(hipMemcpyHtoDAsync(p_frame_uv, p_src_ptr_uv, chroma_size, hip_stream_));
+        } else {
+            // use 2d copy to copy an ROI
+            HIP_API_CALL(hipMemcpy2DAsync(p_frame_uv, dst_pitch, p_src_ptr_uv, src_pitch[1], dst_pitch, chroma_height_, hipMemcpyHostToDevice, hip_stream_));
+        }
+    } else {
+        if (src_pitch[1] == dst_pitch) {
+            int chroma_size = chroma_height_ * dst_pitch;
+            memcpy(p_frame_uv, p_src_ptr_uv, chroma_size);
+        } 
+        else {
+            for (int i = 0; i < chroma_height_; i++) {
+                memcpy(p_frame_uv, p_src_ptr_uv, dst_pitch);
+                p_frame_uv += dst_pitch;
+                p_src_ptr_uv += src_pitch[1];
+            }
+        }
+    }
+
+    if (num_chroma_planes_ == 2) {
+        uint8_t *p_frame_v = p_frame_uv + dst_pitch * chroma_height_;
+        uint8_t *p_src_ptr_v = static_cast<uint8_t *>(src_ptr[2]) + (disp_rect_.top + crop_rect_.top) * src_pitch[2] + ((disp_rect_.left + crop_rect_.left) >> 1) * byte_per_pixel_;
+        if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) {
+            if (src_pitch[2] == dst_pitch) {
+                int chroma_size = chroma_height_ * dst_pitch;
+                HIP_API_CALL(hipMemcpyDtoDAsync(p_frame_v, p_src_ptr_v, chroma_size, hip_stream_));
+            } else {
+                // use 2d copy to copy an ROI
+                HIP_API_CALL(hipMemcpy2DAsync(p_frame_v, dst_pitch, p_src_ptr_v, src_pitch[2], dst_pitch, chroma_height_, hipMemcpyDeviceToDevice, hip_stream_));
+            }            
+        }
+        else {
+            if (src_pitch[2] == dst_pitch) {
+                int chroma_size = chroma_height_ * dst_pitch;
+                memcpy(p_frame_v, p_src_ptr_v, chroma_size);
+            } 
+            else {
+                for (int i = 0; i < chroma_height_; i++) {
+                    memcpy(p_frame_v, p_src_ptr_v, dst_pitch);
+                    p_frame_v += dst_pitch;
+                    p_src_ptr_v += src_pitch[1];
+                }
+            }
+        }         
+    }
+    if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) HIP_API_CALL(hipStreamSynchronize(hip_stream_));
+
+    return 1;
+}
+
+
+int FFMpegVideoDecoder::DecodeFrame(const uint8_t *data, size_t size, int pkt_flags, int64_t pts, int *num_decoded_pics) {
+    output_frame_cnt_ = 0, output_frame_cnt_ret_ = 0;
+    decoded_pic_cnt_ = 0;
+    last_packet_ = { 0 };
+    last_packet_.payload = data;
+    last_packet_.payload_size = size;
+    last_packet_.flags = pkt_flags | ROCDEC_PKT_TIMESTAMP;
+    last_packet_.pts = pts;
+    if (!data || size == 0) {
+        last_packet_.flags |= ROCDEC_PKT_ENDOFSTREAM;
+    }
+    ROCDEC_API_CALL(rocDecParseVideoData(rocdec_parser_, &last_packet_));
+    if (num_decoded_pics) {
+        *num_decoded_pics = decoded_pic_cnt_;
+    }
+    return output_frame_cnt_;
+}
+
+
+uint8_t* FFMpegVideoDecoder::GetFrame(int64_t *pts) {
+    if (output_frame_cnt_ > 0) {
+        std::lock_guard<std::mutex> lock(mtx_vp_frame_);
+        if (vp_frames_ffmpeg_.size() > 0){
+            output_frame_cnt_--;
+            if (pts) *pts = vp_frames_ffmpeg_[output_frame_cnt_ret_].pts;
+            return vp_frames_ffmpeg_[output_frame_cnt_ret_++].frame_ptr;
+        }
+    }
+    return nullptr;
+}
+
+bool FFMpegVideoDecoder::ReleaseFrame(int64_t pTimestamp, bool b_flushing) {
+    // if not flushing the buffers are re-used, so keep them
+    if (out_mem_type_ == OUT_SURFACE_MEM_NOT_MAPPED || !b_flushing)
+        return true;    // nothing to do
+    if (!b_flushing)  
+        return true;
+    else {
+        // remove frames in flushing mode
+        std::lock_guard<std::mutex> lock(mtx_vp_frame_);
+        DecFrameBufferFFMpeg *fb = &vp_frames_ffmpeg_[0];
+        if (pTimestamp != fb->pts) {
+            std::cerr << "Decoded Frame is released out of order" << std::endl;
+            return false;
+        }
+        av_frame_free(&fb->av_frame_ptr);
+        vp_frames_ffmpeg_.erase(vp_frames_ffmpeg_.begin());     // get rid of the frames from the framestore
+    }
+    return true;
+}
+
+void FFMpegVideoDecoder::InitOutputFrameInfo(AVFrame *p_frame) {
+    
+    video_surface_format_ = AVPixelFormat2rocDecVideoSurfaceFormat((AVPixelFormat)p_frame->format);
+    surface_stride_ = target_width_ * byte_per_pixel_;
+    chroma_width_ = static_cast<int>(ceil(target_width_ * GetChromaWidthFactor(video_surface_format_)));
+    chroma_height_ = static_cast<int>(ceil(target_height_ * GetChromaHeightFactor(video_surface_format_)));
+    num_chroma_planes_ = GetChromaPlaneCount(video_surface_format_);
+    // Fill output_surface_info_
+    output_surface_info_.output_width = target_width_;
+    output_surface_info_.output_height = target_height_;
+    output_surface_info_.output_pitch  = surface_stride_;
+    output_surface_info_.output_vstride = target_height_;
+    output_surface_info_.bit_depth = bitdepth_minus_8_ + 8;
+    output_surface_info_.bytes_per_pixel = byte_per_pixel_;
+    output_surface_info_.surface_format = video_surface_format_;
+    output_surface_info_.num_chroma_planes = num_chroma_planes_;
+    if (out_mem_type_ == OUT_SURFACE_MEM_DEV_COPIED) {
+        output_surface_info_.output_surface_size_in_bytes = GetFrameSize();
+        output_surface_info_.mem_type = OUT_SURFACE_MEM_DEV_COPIED;
+    } else if (out_mem_type_ == OUT_SURFACE_MEM_HOST_COPIED) {
+        output_surface_info_.output_surface_size_in_bytes = GetFrameSize();
+        output_surface_info_.mem_type = OUT_SURFACE_MEM_HOST_COPIED;
+    }
+}
+
+void FFMpegVideoDecoder::DecodeThread()
+{
+    AVPacket *pkt;
+    do {
+        pkt = PopPacket();
+        DecodeAvFrame(pkt, dec_frames_[av_frame_cnt_]);
+    } while (!end_of_stream_);
+}
+
+int FFMpegVideoDecoder::DecodeAvFrame(AVPacket *av_pkt, AVFrame *p_frame) {
+    int status;
+    //send packet to av_codec
+    status = avcodec_send_packet(dec_context_, av_pkt);
+    if (status < 0) {
+        std::cout << "Error sending av packet for decoding: status: " << status << std::endl;
+    }
+    while (status >= 0) {
+        status = avcodec_receive_frame(dec_context_, p_frame);
+        if (status == AVERROR(EAGAIN) || status == AVERROR_EOF) {
+            end_of_stream_ = (status == AVERROR_EOF);
+            return 0;
+        }
+        else if (status < 0) {
+            std::cout << "Error during decoding" << std::endl;
+            return 0;
+        }
+        // for the first frame, initialize OutputsurfaceInfo
+        if (dec_context_->frame_number == 1) {
+            InitOutputFrameInfo(p_frame);
+        }
+        decoded_pic_cnt_++;
+        
+        if (no_multithreading_)
+            av_frame_q_.push(p_frame);
+        else
+            PushFrame(p_frame);  // add frame to the frame_q
+        av_frame_cnt_ = (av_frame_cnt_ + 1) % dec_frames_.size();
+        p_frame = dec_frames_[av_frame_cnt_]; //advance for next frame decode
+    }
+    return 0;
+}
+
+
+void FFMpegVideoDecoder::SaveFrameToFile(std::string output_file_name, void *surf_mem, OutputSurfaceInfo *surf_info, size_t rgb_image_size) {
+    uint8_t *hst_ptr = nullptr;
+    bool is_rgb = (rgb_image_size != 0);
+    uint64_t output_image_size = is_rgb ? rgb_image_size : surf_info->output_surface_size_in_bytes;
+    if (surf_info->mem_type == OUT_SURFACE_MEM_DEV_COPIED) {
+        if (hst_ptr == nullptr) {
+            hst_ptr = new uint8_t [output_image_size];
+        }
+        hipError_t hip_status = hipSuccess;
+        hip_status = hipMemcpyDtoH((void *)hst_ptr, surf_mem, output_image_size);
+        if (hip_status != hipSuccess) {
+            std::cerr << "ERROR: hipMemcpyDtoH failed! (" << hipGetErrorName(hip_status) << ")" << std::endl;
+            delete [] hst_ptr;
+            return;
+        }
+    } else
+        hst_ptr = static_cast<uint8_t *> (surf_mem);
+
+    
+    if (current_output_filename.empty()) {
+        current_output_filename = output_file_name;
+    }
+
+    // don't overwrite to the same file if reconfigure is detected for a resolution changes.
+    if (is_decoder_reconfigured_) {
+        if (fp_out_) {
+            fclose(fp_out_);
+            fp_out_ = nullptr;
+        }
+        // Append the width and height of the new stream to the old file name to create a file name to save the new frames
+        // do this only if resolution changes within a stream (e.g., decoding a multi-resolution stream using the videoDecode app)
+        // don't append to the output_file_name if multiple output file name is provided (e.g., decoding multi-files using the videDecodeMultiFiles)
+        if (!current_output_filename.compare(output_file_name)) {
+            std::string::size_type const pos(output_file_name.find_last_of('.'));
+            extra_output_file_count_++;
+            std::string to_append = "_" + std::to_string(surf_info->output_width) + "_" + std::to_string(surf_info->output_height) + "_" + std::to_string(extra_output_file_count_);
+            if (pos != std::string::npos) {
+                output_file_name.insert(pos, to_append);
+            } else {
+                output_file_name += to_append;
+            }
+        }
+        is_decoder_reconfigured_ = false;
+    } 
+
+    if (fp_out_ == nullptr) {
+        fp_out_ = fopen(output_file_name.c_str(), "wb");
+    }
+    if (fp_out_) {
+        if (!is_rgb) {
+            uint8_t *tmp_hst_ptr = hst_ptr;
+            int img_width = surf_info->output_width;
+            int img_height = surf_info->output_height;
+            int output_stride =  surf_info->output_pitch;
+            if (img_width * surf_info->bytes_per_pixel == output_stride && img_height == surf_info->output_vstride) {
+                fwrite(hst_ptr, 1, output_image_size, fp_out_);
+            } else {
+                uint32_t width = surf_info->output_width * surf_info->bytes_per_pixel;
+                if (surf_info->bit_depth <= 16) {
+                    for (int i = 0; i < surf_info->output_height; i++) {
+                        fwrite(tmp_hst_ptr, 1, width, fp_out_);
+                        tmp_hst_ptr += output_stride;
+                    }
+                    // dump chroma
+                    uint32_t chroma_stride = (output_stride >> 1);
+                    uint8_t *u_hst_ptr = hst_ptr + output_stride * surf_info->output_height;
+                    uint8_t *v_hst_ptr = u_hst_ptr + chroma_stride * chroma_height_;
+                    for (int i = 0; i < chroma_height_; i++) {
+                        fwrite(u_hst_ptr, 1, chroma_width_, fp_out_);
+                        u_hst_ptr += chroma_stride;
+                    }
+                    if (num_chroma_planes_ == 2) {
+                        for (int i = 0; i < chroma_height_; i++) {
+                            fwrite(v_hst_ptr, 1, chroma_width_, fp_out_);
+                            v_hst_ptr += chroma_stride;
+                        }
+                    }
+                } 
+            }
+        } else {
+            fwrite(hst_ptr, 1, rgb_image_size, fp_out_);
+        }
+    }
+
+    if (hst_ptr && (surf_info->mem_type != OUT_SURFACE_MEM_HOST_COPIED)) {
+        delete [] hst_ptr;
+    }
+}

utils/ffmpegvideodecode/ffmpeg_video_dec.h

@@ -0,0 +1,236 @@
+/*
+Copyright (c) 2023 - 2024 Advanced Micro Devices, Inc. All rights reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#pragma once
+
+extern "C" {
+    #include <libavcodec/avcodec.h>
+    #include <libavformat/avformat.h>
+    #include <libavutil/pixdesc.h>
+    #if USE_AVCODEC_GREATER_THAN_58_134
+        #include <libavcodec/bsf.h>
+    #endif
+}
+#include "rocvideodecode/roc_video_dec.h"       // for derived class
+
+#include <mutex>
+#include <condition_variable>
+#include <queue>
+#include <atomic>
+
+
+#define MAX_AV_PACKET_DATA_SIZE     4096
+
+typedef struct DecFrameBufferFFMpeg_ {
+    AVFrame *av_frame_ptr;      /**< av_frame pointer for the decoded frame */
+    uint8_t *frame_ptr;       /**< host/device memory pointer for the decoded frame depending on mem_type*/
+    int64_t  pts;             /**<  timestamp for the decoded frame */
+    int picture_index;         /**<  surface index for the decoded frame */
+} DecFrameBufferFFMpeg;
+
+typedef struct DecPacketBuffer_
+{
+    AVPacket *av_pckt;
+    int av_frame_index;
+} DecPacketBuffer;
+
+class FFMpegVideoDecoder: public RocVideoDecoder {
+    public:
+        /**
+         * @brief Construct a new FFMpegVideoDecoder object
+         * 
+         * @param num_threads : number of cpu threads for the decoder
+         * @param out_mem_type : out_mem_type for the decoded surface
+         * @param codec : codec type
+         * @param force_zero_latency : no support in FFMpeg decoding (false)
+         * @param p_crop_rect : to crop output
+         * @param extract_user_SEI_Message : enable to extract SEI
+         * @param disp_delay : output delayed by #disp_delay surfaces
+         * @param max_width : Max. width for the output surface
+         * @param max_height : Max. height for the output surface
+         * @param clk_rate : FPS clock-rate
+         * @param no_multithreading : run FFMpeg decoder in the main thread (no multithreading) 
+         */
+        FFMpegVideoDecoder(int num_threads,  OutputSurfaceMemoryType out_mem_type, rocDecVideoCodec codec, bool force_zero_latency = false,
+                          const Rect *p_crop_rect = nullptr, bool extract_user_SEI_Message = false, uint32_t disp_delay = 0, bool no_multithreading = false, int max_width = 0, int max_height = 0,
+                          uint32_t clk_rate = 1000);
+        /**
+         * @brief destructor
+         * 
+         */
+        ~FFMpegVideoDecoder();
+
+        /**
+         * @brief this function decodes a frame and returns the number of frames avalable for display
+         * 
+         * @param data - pointer to the compressed data buffer that is to be decoded
+         * @param size - size of the data buffer in bytes
+         * @param pts - presentation timestamp
+         * @param flags - video packet flags
+         * @param num_decoded_pics - nummber of pictures decoded in this call
+         * @return int - num of frames to display
+         */
+        int DecodeFrame(const uint8_t *data, size_t size, int pkt_flags, int64_t pts = 0, int *num_decoded_pics = nullptr);
+
+        /**
+         * @brief This function returns a decoded frame and timestamp. This should be called in a loop fetching all the available frames
+         * 
+         */
+        uint8_t* GetFrame(int64_t *pts);
+
+        /**
+         * @brief function to release frame after use by the application: Only used with "OUT_SURFACE_MEM_DEV_INTERNAL"
+         * 
+         * @param pTimestamp - timestamp of the frame to be released (unmapped)
+         * @param b_flushing - true when flushing
+         * @return true      - success
+         * @return false     - falied
+         */
+        bool ReleaseFrame(int64_t pTimestamp, bool b_flushing = false);
+
+        /**
+         * @brief Helper function to dump decoded output surface to file
+         * 
+         * @param output_file_name  - Output file name
+         * @param dev_mem           - pointer to surface memory
+         * @param surf_info         - surface info
+         * @param rgb_image_size    - image size for rgb (optional). A non_zero value indicates the surf_mem holds an rgb interleaved image and the entire size will be dumped to file
+         */
+        void SaveFrameToFile(std::string output_file_name, void *surf_mem, OutputSurfaceInfo *surf_info, size_t rgb_image_size = 0);
+
+        /**
+        *   @brief  This function is used to get the current frame size based on pixel format.
+        */
+        virtual int GetFrameSize() { assert(disp_width_); return ((disp_width_ * disp_height_) + ((chroma_height_ * chroma_width_) * num_chroma_planes_)) * byte_per_pixel_; }
+
+    private:
+        /**
+         *   @brief  Callback function to be registered for getting a callback when decoding of sequence starts
+         */
+        static int ROCDECAPI FFMpegHandleVideoSequenceProc(void *p_user_data, RocdecVideoFormat *p_video_format) { return ((FFMpegVideoDecoder *)p_user_data)->HandleVideoSequence(p_video_format); }
+
+        /**
+         *   @brief  Callback function to be registered for getting a callback when a decoded frame is ready to be decoded
+         */
+        static int ROCDECAPI FFMpegHandlePictureDecodeProc(void *p_user_data, RocdecPicParams *p_pic_params) { return ((FFMpegVideoDecoder *)p_user_data)->HandlePictureDecode(p_pic_params); }
+
+        /**
+         *   @brief  Callback function to be registered for getting a callback when a decoded frame is available for display
+         */
+        static int ROCDECAPI FFMpegHandlePictureDisplayProc(void *p_user_data, RocdecParserDispInfo *p_disp_info) { return ((FFMpegVideoDecoder *)p_user_data)->HandlePictureDisplay(p_disp_info); }
+
+        /**
+         *   @brief  Callback function to be registered for getting a callback when all the unregistered user SEI Messages are parsed for a frame.
+         */
+        static int ROCDECAPI FFMpegHandleSEIMessagesProc(void *p_user_data, RocdecSeiMessageInfo *p_sei_message_info) { return ((FFMpegVideoDecoder *)p_user_data)->GetSEIMessage(p_sei_message_info); } 
+
+        /**
+         *   @brief  This function gets called when a sequence is ready to be decoded. The function also gets called
+             when there is format change
+        */
+        int HandleVideoSequence(RocdecVideoFormat *p_video_format);
+
+        /**
+         *   @brief  This function gets called when a picture is ready to be decoded. cuvidDecodePicture is called from this function
+         *   to decode the picture
+         */
+        int HandlePictureDecode(RocdecPicParams *p_pic_params);
+
+        /**
+         *   @brief  This function gets called after a picture is decoded and available for display. Frames are fetched and stored in 
+             internal buffer
+        */
+        int HandlePictureDisplay(RocdecParserDispInfo *p_disp_info);
+        
+        /**
+         *   @brief  This function gets called when all unregistered user SEI messages are parsed for a frame
+         */
+        int GetSEIMessage(RocdecSeiMessageInfo *p_sei_message_info) { return RocVideoDecoder::GetSEIMessage(p_sei_message_info);};
+
+        /**
+         *   @brief  This function reconfigure decoder if there is a change in sequence params.
+         */
+        int ReconfigureDecoder(RocdecVideoFormat *p_video_format);
+
+        void DecodeThread();
+        int DecodeAvFrame(AVPacket *av_pkt, AVFrame *p_frame);
+        void InitOutputFrameInfo(AVFrame *p_frame);
+        void PushPacket(AVPacket *pkt) {
+            {
+                std::lock_guard<std::mutex> lock(mtx_pkt_q_);
+                av_packet_q_.push(pkt);
+            }
+            cv_pkt_.notify_one();
+        }
+        
+        AVPacket *PopPacket() {
+            AVPacket *pkt;
+            std::unique_lock<std::mutex> lock(mtx_pkt_q_);
+            cv_pkt_.wait(lock, [&] { return !av_packet_q_.empty(); });
+            pkt = av_packet_q_.front();
+            av_packet_q_.pop();
+            return pkt;
+        }
+
+        void PushFrame(AVFrame *av_frame) {
+            {
+                std::lock_guard<std::mutex> lock(mtx_frame_q_);
+                av_frame_q_.push(av_frame);
+            }
+            cv_frame_.notify_one();
+        };
+
+        AVFrame *PopFrame() {
+            std::unique_lock<std::mutex> lock(mtx_frame_q_);
+            cv_frame_.wait(lock, [&] { return !av_frame_q_.empty() || end_of_stream_; });
+            if (end_of_stream_ && av_frame_q_.empty())
+                return nullptr;
+            AVFrame *p_frame = av_frame_q_.front();
+            av_frame_q_.pop();
+            return p_frame;
+        }
+
+        typedef enum { CMD_ABORT, CMD_DECODE } CommandType;
+        typedef enum { STATUS_SUCCESS = 0, STATUS_FAILURE = -1 } StatusType;
+
+        bool no_multithreading_ = false;
+        uint32_t av_frame_cnt_ = 0;
+        uint32_t av_pkt_cnt_ = 0;
+        RocdecSourceDataPacket last_packet_;
+        std::thread *ffmpeg_decoder_thread_ = nullptr;
+        std::queue<AVPacket *> av_packet_q_;        // queue for compressed packets
+        std::queue<AVFrame *> av_frame_q_;
+        std::vector<DecFrameBufferFFMpeg> vp_frames_ffmpeg_;      // vector of decoded frames
+        std::vector<AVFrame *> dec_frames_;      // vector of AVFrame * for decoded frames
+        std::vector<AVPacket *> av_packets_;    // store of AVPackets for decoding
+        std::vector<std::pair<uint8_t *, int>> av_packet_data_;
+        std::mutex mtx_pkt_q_, mtx_frame_q_;               //for command and status
+        std::condition_variable cv_pkt_, cv_frame_;     //for command and status
+        std::atomic<bool> end_of_stream_ = false;
+        // Variables for FFMpeg decoding
+        AVCodecContext * dec_context_ = nullptr;
+        AVPixelFormat decoder_pixel_format_;
+        AVCodec *decoder_ = nullptr;
+        AVFormatContext * formatContext = nullptr;
+        AVInputFormat * inputFormat = nullptr;
+        AVStream *video = nullptr;
+};

utils/rocvideodecode/roc_video_dec.cpp

@@ -196,38 +196,6 @@ static const char * GetVideoChromaFormatName(rocDecVideoChromaFormat e_chroma_fo
     return "Unknown";
 }
 
-static float GetChromaHeightFactor(rocDecVideoSurfaceFormat surface_format) {
-    float factor = 0.5;
-    switch (surface_format) {
-    case rocDecVideoSurfaceFormat_NV12:
-    case rocDecVideoSurfaceFormat_P016:
-        factor = 0.5;
-        break;
-    case rocDecVideoSurfaceFormat_YUV444:
-    case rocDecVideoSurfaceFormat_YUV444_16Bit:
-        factor = 1.0;
-        break;
-    }
-
-    return factor;
-}
-
-static int GetChromaPlaneCount(rocDecVideoSurfaceFormat surface_format) {
-    int num_planes = 1;
-    switch (surface_format) {
-    case rocDecVideoSurfaceFormat_NV12:
-    case rocDecVideoSurfaceFormat_P016:
-        num_planes = 1;
-        break;
-    case rocDecVideoSurfaceFormat_YUV444:
-    case rocDecVideoSurfaceFormat_YUV444_16Bit:
-        num_planes = 2;
-        break;
-    }
-
-    return num_planes;
-}
-
 static void GetSurfaceStrideInternal(rocDecVideoSurfaceFormat surface_format, uint32_t width, uint32_t height, uint32_t *pitch, uint32_t *vstride) {
 
     switch (surface_format) {
@@ -247,6 +215,15 @@ static void GetSurfaceStrideInternal(rocDecVideoSurfaceFormat surface_format, ui
         *pitch = align(width, 128) * 2;
         *vstride = align(height, 16);
         break;
+    case rocDecVideoSurfaceFormat_YUV420:
+        *pitch = align(width, 256);
+        *vstride = align(height, 16);
+        break;
+    case rocDecVideoSurfaceFormat_YUV420_16Bit:
+        *pitch = align(width, 128) * 2;
+        *vstride = align(height, 16);
+        break;
+
     }
     return;
 }

utils/rocvideodecode/roc_video_dec.h

@@ -78,6 +78,45 @@ typedef enum OutputSurfaceMemoryType_enum {
 #endif
 #define ERR(X) std::cerr << "[ERR] "  << " {" << __func__ <<"} " << " " << X << std::endl;
 
+inline int GetChromaPlaneCount(rocDecVideoSurfaceFormat surface_format) {
+    int num_planes = 1;
+    switch (surface_format) {
+    case rocDecVideoSurfaceFormat_NV12:
+    case rocDecVideoSurfaceFormat_P016:
+        num_planes = 1;
+        break;
+    case rocDecVideoSurfaceFormat_YUV444:
+    case rocDecVideoSurfaceFormat_YUV444_16Bit:
+        num_planes = 2;
+        break;
+    case rocDecVideoSurfaceFormat_YUV420:
+    case rocDecVideoSurfaceFormat_YUV420_16Bit:
+        num_planes = 2;
+        break;
+    }
+
+    return num_planes;
+};
+
+inline float GetChromaHeightFactor(rocDecVideoSurfaceFormat surface_format) {
+    float factor = 0.5;
+    switch (surface_format) {
+    case rocDecVideoSurfaceFormat_NV12:
+    case rocDecVideoSurfaceFormat_P016:
+    case rocDecVideoSurfaceFormat_YUV420:
+    case rocDecVideoSurfaceFormat_YUV420_16Bit:
+        factor = 0.5;
+        break;
+    case rocDecVideoSurfaceFormat_YUV444:
+    case rocDecVideoSurfaceFormat_YUV444_16Bit:
+        factor = 1.0;
+        break;
+    }
+
+    return factor;
+};
+
+
 class RocVideoDecodeException : public std::exception {
 public:
 
@@ -162,22 +201,20 @@ typedef struct ReconfigParams_t {
 
 class RocVideoDecoder {
     public:
-      /**
-       * @brief Construct a new Roc Video Decoder object
-       * 
-       * @param hip_ctx 
-       * @param b_use_device_mem 
-       * @param codec 
-       * @param device_id 
-       * @param b_low_latency 
-       * @param device_frame_pitched 
-       * @param p_crop_rect 
-       * @param extract_user_SEI_Message 
-       * @param max_width 
-       * @param max_height 
-       * @param clk_rate 
-       * @param force_zero_latency 
-       */
+        /**
+        * @brief Construct a new Roc Video Decoder object
+        * 
+        * @param device_id : device_id to initialize HIP and VCN
+        * @param out_mem_type : out_mem_type for the decoded surface
+        * @param codec : codec type
+        * @param force_zero_latency : to force zero latency (output in decoding orde)
+        * @param p_crop_rect : to crop output
+        * @param extract_user_SEI_Message : enable to extract SEI
+        * @param disp_delay : output delayed by #disp_delay surfaces
+        * @param max_width : Max. width for the output surface
+        * @param max_height : Max. height for the output surface
+        * @param clk_rate : FPS clock-rate
+        */
         RocVideoDecoder(int device_id,  OutputSurfaceMemoryType out_mem_type, rocDecVideoCodec codec, bool force_zero_latency = false,
                           const Rect *p_crop_rect = nullptr, bool extract_user_SEI_Message = false, uint32_t disp_delay = 0, int max_width = 0, int max_height = 0,
                           uint32_t clk_rate = 1000);
@@ -215,12 +252,8 @@ class RocVideoDecoder {
         /**
         *   @brief  This function is used to get the current frame size based on pixel format.
         */
-        int GetFrameSize() { assert(disp_width_); return disp_width_ * (disp_height_ + (chroma_height_ * num_chroma_planes_)) * byte_per_pixel_; }
+        virtual int GetFrameSize() { assert(disp_width_); return disp_width_ * (disp_height_ + (chroma_height_ * num_chroma_planes_)) * byte_per_pixel_; }
 
-        /**
-        *   @brief  This function is used to get the current frame size based on pitch
-        */
-        int GetFrameSizePitched() { assert(surface_stride_); return surface_stride_ * (disp_height_ + (chroma_height_ * num_chroma_planes_)); }
 
         /**
          * @brief Get the Bit Depth and BytesPerPixel associated with the pixel format
@@ -285,12 +318,12 @@ class RocVideoDecoder {
          * @param num_decoded_pics - nummber of pictures decoded in this call
          * @return int - num of frames to display
          */
-        int DecodeFrame(const uint8_t *data, size_t size, int pkt_flags, int64_t pts = 0, int *num_decoded_pics = nullptr);
+        virtual int DecodeFrame(const uint8_t *data, size_t size, int pkt_flags, int64_t pts = 0, int *num_decoded_pics = nullptr);
         /**
          * @brief This function returns a decoded frame and timestamp. This should be called in a loop fetching all the available frames
          * 
          */
-        uint8_t* GetFrame(int64_t *pts);
+        virtual uint8_t* GetFrame(int64_t *pts);
 
         /**
          * @brief function to release frame after use by the application: Only used with "OUT_SURFACE_MEM_DEV_INTERNAL"
@@ -300,7 +333,7 @@ class RocVideoDecoder {
          * @return true      - success
          * @return false     - falied
          */
-        bool ReleaseFrame(int64_t pTimestamp, bool b_flushing = false);
+        virtual bool ReleaseFrame(int64_t pTimestamp, bool b_flushing = false);
 
         /**
          * @brief utility function to save image to a file
@@ -331,12 +364,12 @@ class RocVideoDecoder {
          * @param surf_info         - surface info
          * @param rgb_image_size    - image size for rgb (optional). A non_zero value indicates the surf_mem holds an rgb interleaved image and the entire size will be dumped to file
          */
-        void SaveFrameToFile(std::string output_file_name, void *surf_mem, OutputSurfaceInfo *surf_info, size_t rgb_image_size = 0);
+        virtual void SaveFrameToFile(std::string output_file_name, void *surf_mem, OutputSurfaceInfo *surf_info, size_t rgb_image_size = 0);
 
         /**
          * @brief Helper funtion to close a existing file and dump to new file in case of multiple files using same decoder
         */
-        void ResetSaveFrameToFile();
+        virtual void ResetSaveFrameToFile();
 
         /**
          * @brief Helper function to start MD5 calculation
@@ -387,7 +420,12 @@ class RocVideoDecoder {
          */
         bool CodecSupported(int device_id, rocDecVideoCodec codec_id, uint32_t bit_depth);
 
-    private:
+        /**
+         *   @brief  This function reconfigure decoder if there is a change in sequence params.
+         */
+        virtual int ReconfigureDecoder(RocdecVideoFormat *p_video_format);
+
+    protected:
         /**
          *   @brief  Callback function to be registered for getting a callback when decoding of sequence starts
          */
@@ -429,11 +467,6 @@ class RocVideoDecoder {
          *   @brief  This function gets called when all unregistered user SEI messages are parsed for a frame
          */
         int GetSEIMessage(RocdecSeiMessageInfo *p_sei_message_info);
-
-        /**
-         *   @brief  This function reconfigure decoder if there is a change in sequence params.
-         */
-        int ReconfigureDecoder(RocdecVideoFormat *p_video_format);
         
         /**
          * @brief function to release all internal frames and clear the vp_frames_q_ (used with reconfigure): Only used with "OUT_SURFACE_MEM_DEV_INTERNAL"
@@ -495,7 +528,7 @@ class RocVideoDecoder {
         uint32_t target_width_ = 0;
         uint32_t target_height_ = 0;
         int max_width_ = 0, max_height_ = 0;
-        uint32_t chroma_height_ = 0;
+        uint32_t chroma_height_ = 0, chroma_width_ = 0;
         uint32_t num_chroma_planes_ = 0;
         uint32_t num_components_ = 0;
         uint32_t surface_stride_ = 0;