Add mechanism to flush last frames during reconfigure (#142)

* add mechanism to flush last frames during reconfigure

* reconfig mode updated support

* addressed review comments

* addressed review comments

* change condition according to review comment

[ROCm/rocdecode commit: a5211189f5]

projects/rocdecode/samples/common.h

@@ -0,0 +1,66 @@
+/*
+Copyright (c) 2023 - 2023 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
+
+#include "roc_video_dec.h"
+
+typedef enum ReconfigFlushMode_enum {
+    RECONFIG_FLUSH_MODE_DUMP_TO_FILE = 0,      /**<  The remaining frames will be dumped to file in this mode */
+    //TODO;; Add new flush modes here : defined by the application
+} ReconfigFlushMode;
+
+// this struct is used by videodecode and videodecodeMultiFiles to dump last frames to file
+typedef struct ReconfigDumpFileStruct_t {
+    bool b_dump_frames_to_file;
+    std::string output_file_name;
+} ReconfigDumpFileStruct;
+
+
+// callback function to flush last frames and save it to file when reconfigure happens
+int ReconfigureFlushCallback(void *p_viddec_obj, uint32_t flush_mode, void *p_user_struct) {
+    int n_frames_flushed = 0;
+    if ((p_viddec_obj == nullptr) ||  (p_user_struct == nullptr)) return n_frames_flushed;
+
+    RocVideoDecoder *viddec = static_cast<RocVideoDecoder *> (p_viddec_obj);
+    OutputSurfaceInfo *surf_info;
+    if (!viddec->GetOutputSurfaceInfo(&surf_info)) {
+        std::cerr << "Error: Failed to get Output Surface Info!" << std::endl;
+        return n_frames_flushed;
+    }
+    if (flush_mode == ReconfigFlushMode::RECONFIG_FLUSH_MODE_DUMP_TO_FILE) {
+        ReconfigDumpFileStruct *p_dump_file_struct = static_cast<ReconfigDumpFileStruct *>(p_user_struct);
+        uint8_t *pframe = nullptr;
+        int64_t pts;
+        while ((pframe = viddec->GetFrame(&pts))) {
+            if (p_dump_file_struct->b_dump_frames_to_file) {
+                viddec->SaveFrameToFile(p_dump_file_struct->output_file_name, pframe, surf_info);
+            }
+            // release and flush frame
+            viddec->ReleaseFrame(pts, true);
+            n_frames_flushed ++;
+        }
+    } else {
+        //todo:: handle other cases
+    }
+    return n_frames_flushed;
+}