feature: Allow use of secondary stream for analysis/motion detection

src/CMakeLists.txt

@@ -15,6 +15,7 @@ set(ZM_BIN_SRC_FILES
   zm.cpp
   zm_db.cpp
   zm_decoder_thread.cpp
+  zm_second_stream_thread.cpp
   zm_group_permission.cpp
   zm_monitor_permission.cpp
   zm_logger.cpp

src/zm_ffmpeg.cpp

@@ -415,6 +415,24 @@ void zm_dump_codecpar(const AVCodecParameters *par) {
        );
 }
 
+void zm_set_rtsp_transport_method(AVDictionary **opts, const std::string &method) {
+  int ret = 0;
+  if (method == "rtpMulti") {
+    ret = av_dict_set(opts, "rtsp_transport", "udp_multicast", 0);
+  } else if (method == "rtpRtsp") {
+    ret = av_dict_set(opts, "rtsp_transport", "tcp", 0);
+  } else if (method == "rtpRtspHttp") {
+    ret = av_dict_set(opts, "rtsp_transport", "http", 0);
+  } else if (method == "rtpUni") {
+    ret = av_dict_set(opts, "rtsp_transport", "udp", 0);
+  } else {
+    Warning("Unknown method (%s)", method.c_str());
+  }
+  if (ret < 0) {
+    Warning("Could not set rtsp_transport method '%s'", method.c_str());
+  }
+}
+
 void zm_dump_codec(const AVCodecContext *codec) {
   Debug(1, "Dumping codec_context codec_type %d %s codec_id %d %s tag %c%c%c%c width %d height %d timebase %d/%d format %s profile %d level %d "
         "gop_size %d has_b_frames %d max_b_frames %d me_cmp %d me_range %d qmin %d qmax %d bit_rate %" PRId64 " qcompress %f extradata:%d:%s",

src/zm_ffmpeg.h

@@ -149,6 +149,12 @@ void zm_dump_stream_format(AVFormatContext *ic, int i, int index, int is_output)
 void zm_dump_codec(const AVCodecContext *codec);
 void zm_dump_codecpar(const AVCodecParameters *par);
 
+// Map a monitor's Method setting (rtpMulti/rtpRtsp/rtpRtspHttp/rtpUni) to the
+// ffmpeg rtsp demuxer's rtsp_transport option.  Warns on an unknown method or
+// a failure to set the option.  Shared by the primary FfmpegCamera open path
+// and the analysis-substream sidecar so both streams use the same transport.
+void zm_set_rtsp_transport_method(AVDictionary **opts, const std::string &method);
+
 #if LIBAVUTIL_VERSION_CHECK(57, 28, 100, 28, 0)
 #define zm_dump_frame(frame, text) Debug(1, "%s: format %d %s sample_rate %" PRIu32 " nb_samples %d" \
       " layout %" PRIu64 " pts %" PRId64, \

src/zm_ffmpeg_camera.cpp

@@ -127,6 +127,13 @@ FfmpegCamera::FfmpegCamera(
 FfmpegCamera::~FfmpegCamera() {
   Close();
 
+  // mSecondFormatContext is a non-owning alias into mSecondInput's AVFormatContext
+  // (set in OpenFfmpeg from mSecondInput->get_format_context()). mSecondInput, a
+  // unique_ptr<FFmpeg_Input>, closes and frees that context in its own destructor,
+  // so clear the alias here to stop the base Camera::~Camera() from freeing the same
+  // context a second time (double free -> crash in avformat_free_context/av_opt_free).
+  mSecondFormatContext = nullptr;
+
   FFMPEGDeInit();
 }
 
@@ -477,21 +484,7 @@ int FfmpegCamera::OpenFfmpeg() {
   std::string protocol = mPath.substr(0, 4);
   protocol = StringToUpper(protocol);
   if ( protocol == "RTSP" ) {
-    const std::string method = Method();
-    if ( method == "rtpMulti" ) {
-      ret = av_dict_set(&opts, "rtsp_transport", "udp_multicast", 0);
-    } else if ( method == "rtpRtsp" ) {
-      ret = av_dict_set(&opts, "rtsp_transport", "tcp", 0);
-    } else if ( method == "rtpRtspHttp" ) {
-      ret = av_dict_set(&opts, "rtsp_transport", "http", 0);
-    } else if ( method == "rtpUni" ) {
-      ret = av_dict_set(&opts, "rtsp_transport", "udp", 0);
-    } else {
-      Warning("Unknown method (%s)", method.c_str());
-    }
-    if (ret < 0) {
-      Warning("Could not set rtsp_transport method '%s'", method.c_str());
-    }
+    zm_set_rtsp_transport_method(&opts, Method());
   } else if (protocol == "V4L2") {
     avdevice_register_all();
     input_format = av_find_input_format("video4linux2");

src/zm_ffmpeg_input.cpp

@@ -38,11 +38,11 @@ int FFmpeg_Input::Open(
   return 1;
 }
 
-int FFmpeg_Input::Open(const char *filepath) {
+int FFmpeg_Input::Open(const char *filepath, AVDictionary **options) {
   int error;
 
   /** Open the input file to read from it. */
-  error = avformat_open_input(&input_format_context, filepath, nullptr, nullptr);
+  error = avformat_open_input(&input_format_context, filepath, nullptr, options);
   if ( error < 0 ) {
     if (std::string(filepath).find("incomplete") != std::string::npos) {
       Warning("Could not open input file '%s' (error '%s')",
@@ -97,6 +97,12 @@ int FFmpeg_Input::Open(const char *filepath) {
     std::list<const CodecData *>codec_data = get_decoder_data(input_format_context->streams[i]->codecpar->codec_id, "auto");
     for (auto it = codec_data.begin(); it != codec_data.end(); it ++) {
       const CodecData *chosen_codec_data = *it;
+#if HAVE_LIBAVUTIL_HWCONTEXT_H && LIBAVCODEC_VERSION_CHECK(57, 107, 0, 107, 0)
+      if (no_hwaccel and (chosen_codec_data->hwdevice_type != AV_HWDEVICE_TYPE_NONE)) {
+        Debug(1, "Skipping hardware codec %s (software decoding forced)", chosen_codec_data->codec_name);
+        continue;
+      }
+#endif
       Debug(1, "Found codec %s", chosen_codec_data->codec_name);
 
       streams[i].codec = avcodec_find_decoder_by_name(chosen_codec_data->codec_name);

src/zm_ffmpeg_input.h

@@ -16,7 +16,11 @@ class FFmpeg_Input {
   FFmpeg_Input();
   ~FFmpeg_Input();
 
-  int Open(const char *filename );
+  int Open(const char *filename, AVDictionary **options = nullptr);
+  // Force software decoding (skip hardware decoders / hwaccel setup).  Must be
+  // called before Open().  Used by callers that cannot handle hardware-format
+  // frames, e.g. the analysis substream sidecar.
+  void set_no_hwaccel(bool v) { no_hwaccel = v; }
   int Open(
     const AVStream *,
     const AVCodecContext *,
@@ -55,6 +59,7 @@ class FFmpeg_Input {
   av_frame_ptr frame;
   int64_t last_seek_request;
   AVBufferRef *hw_device_ctx;
+  bool no_hwaccel = false;
 };
 
 #endif