splitmuxsink: Add option to split at exactly max-size-time

Will try to request a keyframe from the encoder to be sent at the target
running time.

https://bugzilla.gnome.org/show_bug.cgi?id=769664

gst/multifile/gstsplitmuxsink.c

@@ -55,6 +55,7 @@
 
 #include <string.h>
 #include <glib/gstdio.h>
+#include <gst/video/video.h>
 #include "gstsplitmuxsink.h"
 
 GST_DEBUG_CATEGORY_STATIC (splitmux_debug);
@@ -71,6 +72,7 @@ enum
   PROP_LOCATION,
   PROP_MAX_SIZE_TIME,
   PROP_MAX_SIZE_BYTES,
+  PROP_SEND_KEYFRAME_REQUESTS,
   PROP_MAX_FILES,
   PROP_MUXER_OVERHEAD,
   PROP_MUXER,
@@ -81,6 +83,7 @@ enum
 #define DEFAULT_MAX_SIZE_BYTES      0
 #define DEFAULT_MAX_FILES           0
 #define DEFAULT_MUXER_OVERHEAD      0.02
+#define DEFAULT_SEND_KEYFRAME_REQUESTS FALSE
 #define DEFAULT_MUXER "mp4mux"
 #define DEFAULT_SINK "filesink"
 
@@ -207,11 +210,18 @@ gst_splitmux_sink_class_init (GstSplitMuxSinkClass * klass)
       g_param_spec_uint64 ("max-size-bytes", "Max. size bytes",
           "Max. amount of data per file (in bytes, 0=disable)", 0, G_MAXUINT64,
           DEFAULT_MAX_SIZE_BYTES, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+  g_object_class_install_property (gobject_class, PROP_SEND_KEYFRAME_REQUESTS,
+      g_param_spec_boolean ("send-keyframe-requests",
+          "Request keyframes at max-size-time",
+          "Request a keyframe every max-size-time ns to try splitting at that point. "
+          "Needs max-size-bytes to be 0 in order to be effective.",
+          DEFAULT_SEND_KEYFRAME_REQUESTS,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
   g_object_class_install_property (gobject_class, PROP_MAX_FILES,
       g_param_spec_uint ("max-files", "Max files",
           "Maximum number of files to keep on disk. Once the maximum is reached,"
-          "old files start to be deleted to make room for new ones.",
-          0, G_MAXUINT, DEFAULT_MAX_FILES,
+          "old files start to be deleted to make room for new ones.", 0,
+          G_MAXUINT, DEFAULT_MAX_FILES,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 
 
@@ -246,6 +256,7 @@ gst_splitmux_sink_init (GstSplitMuxSink * splitmux)
   splitmux->threshold_time = DEFAULT_MAX_SIZE_TIME;
   splitmux->threshold_bytes = DEFAULT_MAX_SIZE_BYTES;
   splitmux->max_files = DEFAULT_MAX_FILES;
+  splitmux->send_keyframe_requests = DEFAULT_SEND_KEYFRAME_REQUESTS;
 
   GST_OBJECT_FLAG_SET (splitmux, GST_ELEMENT_FLAG_SINK);
 }
@@ -320,6 +331,11 @@ gst_splitmux_sink_set_property (GObject * object, guint prop_id,
       splitmux->threshold_time = g_value_get_uint64 (value);
       GST_OBJECT_UNLOCK (splitmux);
       break;
+    case PROP_SEND_KEYFRAME_REQUESTS:
+      GST_OBJECT_LOCK (splitmux);
+      splitmux->send_keyframe_requests = g_value_get_boolean (value);
+      GST_OBJECT_UNLOCK (splitmux);
+      break;
     case PROP_MAX_FILES:
       GST_OBJECT_LOCK (splitmux);
       splitmux->max_files = g_value_get_uint (value);
@@ -372,6 +388,11 @@ gst_splitmux_sink_get_property (GObject * object, guint prop_id,
       g_value_set_uint64 (value, splitmux->threshold_time);
       GST_OBJECT_UNLOCK (splitmux);
       break;
+    case PROP_SEND_KEYFRAME_REQUESTS:
+      GST_OBJECT_LOCK (splitmux);
+      g_value_set_boolean (value, splitmux->send_keyframe_requests);
+      GST_OBJECT_UNLOCK (splitmux);
+      break;
     case PROP_MAX_FILES:
       GST_OBJECT_LOCK (splitmux);
       g_value_set_uint (value, splitmux->max_files);
@@ -601,6 +622,22 @@ complete_or_wait_on_out (GstSplitMuxSink * splitmux, MqStreamCtx * ctx)
   } while (1);
 }
 
+static gboolean
+request_next_keyframe (GstSplitMuxSink * splitmux)
+{
+  GstEvent *ev;
+
+  if (splitmux->send_keyframe_requests == FALSE || splitmux->threshold_time == 0
+      || splitmux->threshold_bytes != 0)
+    return TRUE;
+
+  ev = gst_video_event_new_upstream_force_key_unit (splitmux->fragment_id *
+      splitmux->threshold_time, TRUE, 0);
+  GST_DEBUG_OBJECT (splitmux, "Requesting next keyframe at %" GST_TIME_FORMAT,
+      GST_TIME_ARGS (splitmux->fragment_id * splitmux->threshold_time));
+  return gst_pad_push_event (splitmux->reference_ctx->sinkpad, ev);
+}
+
 static GstPadProbeReturn
 handle_mq_output (GstPad * pad, GstPadProbeInfo * info, MqStreamCtx * ctx)
 {
@@ -715,6 +752,9 @@ handle_mq_output (GstPad * pad, GstPadProbeInfo * info, MqStreamCtx * ctx)
       pad, GST_STIME_ARGS (ctx->out_running_time), buf_info->buf_size);
 
   if (splitmux->opening_first_fragment) {
+    if (request_next_keyframe (splitmux) == FALSE)
+      GST_WARNING_OBJECT (splitmux,
+          "Could not request a keyframe. Files may not split at the exact location they should");
     send_fragment_opened_closed_msg (splitmux, TRUE);
     splitmux->opening_first_fragment = FALSE;
   }
@@ -726,6 +766,7 @@ handle_mq_output (GstPad * pad, GstPadProbeInfo * info, MqStreamCtx * ctx)
     splitmux->muxed_out_time = buf_info->run_ts;
 
   splitmux->muxed_out_bytes += buf_info->buf_size;
+  splitmux->last_frame_duration = buf_info->duration;
 
 #ifndef GST_DISABLE_GST_DEBUG
   {
@@ -807,6 +848,8 @@ start_next_fragment (GstSplitMuxSink * splitmux)
 
   /* Store the overflow parameters as the basis for the next fragment */
   splitmux->mux_start_time = splitmux->muxed_out_time;
+  if (splitmux->last_frame_duration != GST_CLOCK_STIME_NONE)
+    splitmux->mux_start_time += splitmux->last_frame_duration;
   splitmux->mux_start_bytes = splitmux->muxed_out_bytes;
 
   GST_DEBUG_OBJECT (splitmux,
@@ -814,6 +857,9 @@ start_next_fragment (GstSplitMuxSink * splitmux)
       GST_STIME_ARGS (splitmux->max_out_running_time));
 
   send_fragment_opened_closed_msg (splitmux, TRUE);
+  if (request_next_keyframe (splitmux) == FALSE)
+    GST_WARNING_OBJECT (splitmux,
+        "Could not request a keyframe. Files may not split at the exact location they should");
 
   GST_SPLITMUX_BROADCAST (splitmux);
 }
@@ -907,7 +953,6 @@ handle_gathered_gop (GstSplitMuxSink * splitmux)
                   queued_time > splitmux->threshold_time)))) {
 
     splitmux->state = SPLITMUX_STATE_ENDING_FILE;
-
     GST_INFO_OBJECT (splitmux,
         "mq overflowed since last, draining out. max out TS is %"
         GST_STIME_FORMAT, GST_STIME_ARGS (splitmux->max_out_running_time));
@@ -1160,6 +1205,7 @@ handle_mq_input (GstPad * pad, GstPadProbeInfo * info, MqStreamCtx * ctx)
 
   buf_info->run_ts = ctx->in_running_time;
   buf_info->buf_size = gst_buffer_get_size (buf);
+  buf_info->duration = GST_BUFFER_DURATION (buf);
 
   /* Update total input byte counter for overflow detect */
   ctx->in_bytes += buf_info->buf_size;
@@ -1659,7 +1705,7 @@ gst_splitmux_sink_change_state (GstElement * element, GstStateChange transition)
       splitmux->state = SPLITMUX_STATE_COLLECTING_GOP_START;
       splitmux->max_in_running_time = GST_CLOCK_STIME_NONE;
       splitmux->muxed_out_time = splitmux->mux_start_time =
-          GST_CLOCK_STIME_NONE;
+          splitmux->last_frame_duration = GST_CLOCK_STIME_NONE;
       splitmux->muxed_out_bytes = splitmux->mux_start_bytes = 0;
       splitmux->opening_first_fragment = TRUE;
       GST_SPLITMUX_UNLOCK (splitmux);

gst/multifile/gstsplitmuxsink.h

@@ -50,6 +50,7 @@ typedef struct _MqStreamBuf
   gboolean keyframe;
   GstClockTimeDiff run_ts;
   gsize buf_size;
+  GstClockTime duration;
 } MqStreamBuf;
 
 typedef struct _MqStreamCtx
@@ -95,6 +96,7 @@ struct _GstSplitMuxSink {
   GstClockTime threshold_time;
   guint64 threshold_bytes;
   guint max_files;
+  gboolean send_keyframe_requests;
 
   guint mq_max_buffers;
 
@@ -123,6 +125,7 @@ struct _GstSplitMuxSink {
 
   GstClockTimeDiff mux_start_time;
   gsize mux_start_bytes;
+  GstClockTime last_frame_duration;
 
   gboolean opening_first_fragment;
   gboolean switching_fragment;