X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=src%2Flib%2Fdcp_decoder.cc;h=19831185d16203834393335716420998b4a64e84;hb=8f8730cadb3dae36e8aa7b7c732a7c162eac0fb6;hp=95cad926620ad9a4824b40e8ff1914331d3e776e;hpb=19f51503621a57794bd79bac053c9e6549a69f46;p=dcpomatic.git

diff --git a/src/lib/dcp_decoder.cc b/src/lib/dcp_decoder.cc
index 95cad9266..19831185d 100644
--- a/src/lib/dcp_decoder.cc
+++ b/src/lib/dcp_decoder.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2014-2018 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2014-2019 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -28,6 +28,8 @@
 #include "ffmpeg_image_proxy.h"
 #include "image.h"
 #include "config.h"
+#include "digester.h"
+#include "frame_interval_checker.h"
 #include <dcp/dcp.h>
 #include <dcp/cpl.h>
 #include <dcp/reel.h>
@@ -52,6 +54,7 @@
 
 using std::list;
 using std::cout;
+using std::string;
 using boost::shared_ptr;
 using boost::dynamic_pointer_cast;
 using boost::optional;
@@ -75,16 +78,18 @@ DCPDecoder::DCPDecoder (shared_ptr<const Film> film, shared_ptr<const DCPContent
 		}
 	}
 
-	if (old) {
-		_reels = old->_reels;
+	/* We try to avoid re-scanning the DCP's files every time we make a new DCPDecoder; we do this
+	   by re-using the _reels list.  Before we do this we need to check that nothing too serious
+	   has changed in the DCPContent.
 
-		/* We might have gained a KDM since we made the Reel objects */
-		if (_dcp_content->kdm ()) {
-			dcp::DecryptedKDM k = decrypted_kdm ();
-			BOOST_FOREACH (shared_ptr<dcp::Reel> i, _reels) {
-				i->add (k);
-			}
-		}
+	   We do this by storing a digest of the important bits of the DCPContent and then checking that's
+	   the same before we re-use _reels.
+	*/
+
+	_lazy_digest = calculate_lazy_digest (c);
+
+	if (old && old->lazy_digest() == _lazy_digest) {
+		_reels = old->_reels;
 	} else {
 
 		list<shared_ptr<dcp::CPL> > cpl_list = cpls ();
@@ -121,7 +126,14 @@ DCPDecoder::DCPDecoder (shared_ptr<const Film> film, shared_ptr<const DCPContent
 bool
 DCPDecoder::pass ()
 {
-	if (_reel == _reels.end () || !_dcp_content->can_be_played ()) {
+	if (!_dcp_content->can_be_played()) {
+		return true;
+	}
+
+	if (_reel == _reels.end()) {
+		if (audio) {
+			audio->flush ();
+		}
 		return true;
 	}
 
@@ -219,8 +231,14 @@ void
 DCPDecoder::pass_texts (ContentTime next, dcp::Size size)
 {
 	list<shared_ptr<TextDecoder> >::const_iterator decoder = text.begin ();
+	if (decoder == text.end()) {
+		/* It's possible that there is now a main subtitle but no TextDecoders, for example if
+		   the CPL has just changed but the TextContent's texts have not been recreated yet.
+		*/
+		return;
+	}
+
 	if ((*_reel)->main_subtitle()) {
-		DCPOMATIC_ASSERT (decoder != text.end ());
 		pass_texts (
 			next,
 			(*_reel)->main_subtitle()->asset(),
@@ -231,8 +249,8 @@ DCPDecoder::pass_texts (ContentTime next, dcp::Size size)
 			);
 		++decoder;
 	}
+
 	BOOST_FOREACH (shared_ptr<dcp::ReelClosedCaptionAsset> i, (*_reel)->closed_captions()) {
-		DCPOMATIC_ASSERT (decoder != text.end ());
 		pass_texts (
 			next, i->asset(), _dcp_content->reference_text(TEXT_CLOSED_CAPTION), i->entry_point().get_value_or(0), *decoder, size
 			);
@@ -425,3 +443,24 @@ DCPDecoder::set_forced_reduction (optional<int> reduction)
 {
 	_forced_reduction = reduction;
 }
+
+string
+DCPDecoder::calculate_lazy_digest (shared_ptr<const DCPContent> c) const
+{
+	Digester d;
+	BOOST_FOREACH (boost::filesystem::path i, c->paths()) {
+		d.add (i.string());
+	}
+	d.add (static_cast<bool>(_dcp_content->kdm()));
+	d.add (static_cast<bool>(c->cpl()));
+	if (c->cpl()) {
+		d.add (c->cpl().get());
+	}
+	return d.get ();
+}
+
+ContentTime
+DCPDecoder::position () const
+{
+	return ContentTime::from_frames(_offset, _dcp_content->active_video_frame_rate(film())) + _next;
+}