Fixed bug with videoDecodeBatch (#375)

* fixed bug with videoDecodeBatch

* changed if statement to check n_frame_returned

[ROCm/rocdecode commit: 1b9dd60837]

projects/rocdecode/samples/videoDecodeBatch/videodecodebatch.cpp

@@ -125,9 +125,11 @@ void DecProc(RocVideoDecoder *p_dec, VideoDemuxer *demuxer, int *pn_frame, doubl
         n_frame_returned = p_dec->DecodeFrame(p_video, n_video_bytes, 0, pts);
         n_frame += n_frame_returned;
         if (b_dump_output_frames && mem_type != OUT_SURFACE_MEM_NOT_MAPPED) {
-            if (!n_frame && !p_dec->GetOutputSurfaceInfo(&surf_info)) {
-                std::cerr << "Error: Failed to get Output Surface Info!" << std::endl;
-                break;
+            if (n_frame_returned) {
+                if (!p_dec->GetOutputSurfaceInfo(&surf_info)) {
+                    std::cerr << "Error: Failed to get Output Surface Info!" << std::endl;
+                    break;
+                }
             }
             for (int i = 0; i < n_frame_returned; i++) {
                 p_frame = p_dec->GetFrame(&pts);