X-Git-Url: https://git.carlh.net/gitweb/?a=blobdiff_plain;f=src%2Flib%2Futil.cc;h=340b76b57bfaad0eb762ea98ba73a64497d351b8;hb=90550787a8b00329170a6a1d0e9bb58aeb92ac6f;hp=7f370b89647557199657f47b4d47037ec5b552c0;hpb=71ea64782f215c605877f5c231a2a8b1838fe8bd;p=dcpomatic.git

diff --git a/src/lib/util.cc b/src/lib/util.cc
index 7f370b896..340b76b57 100644
--- a/src/lib/util.cc
+++ b/src/lib/util.cc
@@ -26,6 +26,7 @@
 #include <iomanip>
 #include <iostream>
 #include <fstream>
+#include <climits>
 #ifdef DVDOMATIC_POSIX
 #include <execinfo.h>
 #include <cxxabi.h>
@@ -58,9 +59,11 @@ extern "C" {
 #include "dcp_content_type.h"
 #include "filter.h"
 #include "sound_processor.h"
+#include "config.h"
 
 using namespace std;
 using namespace boost;
+using libdcp::Size;
 
 thread::id ui_thread;
 
@@ -230,6 +233,8 @@ seconds (struct timeval t)
 void
 dvdomatic_setup ()
 {
+	avfilter_register_all ();
+	
 	Format::setup_formats ();
 	DCPContentType::setup_dcp_content_types ();
 	Scaler::setup_scalers ();
@@ -330,25 +335,100 @@ md5_digest (string file)
 	return s.str ();
 }
 
-/** @param fps Arbitrary frames-per-second value.
- *  @return DCPFrameRate for this frames-per-second.
- */
-DCPFrameRate
-dcp_frame_rate (float fps)
+static bool about_equal (float a, float b)
+{
+	/* A film of F seconds at f FPS will be Ff frames;
+	   Consider some delta FPS d, so if we run the same
+	   film at (f + d) FPS it will last F(f + d) seconds.
+
+	   Hence the difference in length over the length of the film will
+	   be F(f + d) - Ff frames
+	    = Ff + Fd - Ff frames
+	    = Fd frames
+	    = Fd/f seconds
+ 
+	   So if we accept a difference of 1 frame, ie 1/f seconds, we can
+	   say that
+
+	   1/f = Fd/f
+	ie 1 = Fd
+	ie d = 1/F
+ 
+	   So for a 3hr film, ie F = 3 * 60 * 60 = 10800, the acceptable
+	   FPS error is 1/F ~= 0.0001 ~= 10-e4
+	*/
+
+	return (fabs (a - b) < 1e-4);
+}
+
+class FrameRateCandidate
+{
+public:
+	FrameRateCandidate (float source_, int dcp_)
+		: source (source_)
+		, dcp (dcp_)
+	{}
+
+	bool skip () const {
+		return !about_equal (source, dcp) && source > dcp;
+	}
+
+	bool repeat () const {
+		return !about_equal (source, dcp) && source < dcp;
+	}
+
+	float source;
+	int dcp;
+};
+
+/** @param fps Arbitrary source frames-per-second value */
+/** XXX: this could be slow-ish */
+DCPFrameRate::DCPFrameRate (float source_fps)
 {
-	DCPFrameRate dfr;
+	list<int> const allowed_dcp_frame_rates = Config::instance()->allowed_dcp_frame_rates ();
+
+	/* Work out what rates we could manage, including those achieved by using skip / repeat. */
+	list<FrameRateCandidate> candidates;
+
+	/* Start with the ones without skip / repeat so they will get matched in preference to skipped/repeated ones */
+	for (list<int>::const_iterator i = allowed_dcp_frame_rates.begin(); i != allowed_dcp_frame_rates.end(); ++i) {
+		candidates.push_back (FrameRateCandidate (*i, *i));
+	}
+
+	/* Then the skip/repeat ones */
+	for (list<int>::const_iterator i = allowed_dcp_frame_rates.begin(); i != allowed_dcp_frame_rates.end(); ++i) {
+		candidates.push_back (FrameRateCandidate (float (*i) / 2, *i));
+		candidates.push_back (FrameRateCandidate (float (*i) * 2, *i));
+	}
+
+	/* Pick the best one, bailing early if we hit an exact match */
+	float error = numeric_limits<float>::max ();
+	boost::optional<FrameRateCandidate> best;
+	list<FrameRateCandidate>::iterator i = candidates.begin();
+	while (i != candidates.end()) {
+		
+		if (about_equal (i->source, source_fps)) {
+			best = *i;
+			break;
+		}
 
-	dfr.run_fast = (fps != rint (fps));
-	dfr.frames_per_second = rint (fps);
-	dfr.skip = 1;
+		float const e = fabs (i->source - source_fps);
+		if (e < error) {
+			error = e;
+			best = *i;
+		}
 
-	/* XXX: somewhat arbitrary */
-	if (fps == 50) {
-		dfr.frames_per_second = 25;
-		dfr.skip = 2;
+		++i;
 	}
 
-	return dfr;
+	if (!best) {
+		throw EncodeError ("cannot find a suitable DCP frame rate for this source");
+	}
+
+	frames_per_second = best->dcp;
+	skip = best->skip ();
+	repeat = best->repeat ();
+	change_speed = !about_equal (source_fps * factor(), frames_per_second);
 }
 
 /** @param An arbitrary sampling rate.
@@ -542,6 +622,9 @@ Socket::read_definite_and_consume (uint8_t* data, int size, int timeout)
 /** Read as much data as is available, up to some limit.
  *  @param data Where to put the data.
  *  @param size Maximum amount of data to read.
+ *
+ *  XXX This method assumes that there is always lots of data to read();
+ *  if there isn't, it will hang waiting for data that will never arrive.
  */
 void
 Socket::read_indefinite (uint8_t* data, int size, int timeout)
@@ -854,11 +937,7 @@ video_frames_to_audio_frames (SourceFrame v, float audio_sample_rate, float fram
 bool
 still_image_file (string f)
 {
-#if BOOST_FILESYSTEM_VERSION == 3
 	string ext = boost::filesystem::path(f).extension().string();
-#else
-	string ext = boost::filesystem::path(f).extension();
-#endif
 
 	transform (ext.begin(), ext.end(), ext.begin(), ::tolower);