keycontrol: print Transmitted vfmt + in codec

- s/Captured/Transmitted/ video format (has compressed codec)
- print the input codec in brackets
- do not parse the format from istringstream and print directly

Author: MartinPulec

src/keyboard_control.cpp

@@ -5,7 +5,7 @@
  * With code taken from Olivier Mehani (set_tio()).
  */
 /*
- * Copyright (c) 2015-2024 CESNET
+ * Copyright (c) 2015-2025 CESNET, zájmové sdružení právnických osob
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -764,15 +764,12 @@ void keyboard_control::impl::info()
         }
 
 	{
-		struct video_desc desc{};
                 struct msg_sender *m = (struct msg_sender *) new_message(sizeof(struct msg_sender));
                 m->type = SENDER_MSG_QUERY_VIDEO_MODE;
                 struct response *r = send_message_sync(m_root, "sender", (struct message *) m, 100,  SEND_MESSAGE_FLAG_QUIET | SEND_MESSAGE_FLAG_NO_STORE);
                 if (response_get_status(r) == RESPONSE_OK) {
                         const char *text = response_get_text(r);
-                        istringstream iss(text);
-                        iss >> desc;
-                        col() << TBOLD("Captured video format: ") << desc << "\n";
+                        col() << TBOLD("Transmitted video format: ") << text << "\n";
                 }
                 free_response(r);
 	}

src/video_rxtx.cpp

@@ -158,10 +158,12 @@ void video_rxtx::send(shared_ptr<video_frame> frame) {
         if (!frame && m_poisoned) {
                 return;
         }
-        compress_frame(m_compression, frame);
         if (!frame) {
                 m_poisoned = true;
+        } else {
+                m_input_codec = frame->color_spec;
         }
+        compress_frame(m_compression, frame);
 }
 
 void *video_rxtx::sender_thread(void *args) {
@@ -179,7 +181,9 @@ void video_rxtx::check_sender_messages() {
                                 r = new_response(RESPONSE_NO_CONTENT, nullptr);
                         } else {
                                 ostringstream oss;
-                                oss << m_video_desc;
+                                oss << m_video_desc
+                                    << " (input " << get_codec_name(m_input_codec)
+                                    << ")";
                                 r = new_response(RESPONSE_OK,
                                                  oss.str().c_str());
                         }

src/video_rxtx.hpp

@@ -38,6 +38,7 @@
 #ifndef VIDEO_RXTX_H_
 #define VIDEO_RXTX_H_
 
+#include <atomic>
 #include <map>
 #include <memory>
 #include <string>
@@ -124,6 +125,7 @@ struct video_rxtx {
         bool m_poisoned, m_joined;
 
         video_desc       m_video_desc{};
+        std::atomic<codec_t> m_input_codec{};
 };
 
 class video_rxtx_loader {