From 02478f9f6af48b6209a8e87401025237b7461986 Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Thu, 2 Jul 2015 22:32:12 +0100
Subject: [PATCH] Add bits per pixel to video content properties.

---
 src/lib/ffmpeg_content.cc  | 34 +++++++++++++++++++++-------------
 src/lib/ffmpeg_content.h   |  1 +
 src/lib/ffmpeg_examiner.cc |  8 ++++++++
 src/lib/ffmpeg_examiner.h  |  2 ++
 4 files changed, 32 insertions(+), 13 deletions(-)

diff --git a/src/lib/ffmpeg_content.cc b/src/lib/ffmpeg_content.cc
index 9d3a79e81..384b10233 100644
--- a/src/lib/ffmpeg_content.cc
+++ b/src/lib/ffmpeg_content.cc
@@ -99,13 +99,13 @@ FFmpegContent::FFmpegContent (shared_ptr<const Film> film, cxml::ConstNodePtr no
 
 	_first_video = node->optional_number_child<double> ("FirstVideo");
 
-
 	_color_range = static_cast<AVColorRange> (node->optional_number_child<int>("ColorRange").get_value_or (AVCOL_RANGE_UNSPECIFIED));
 	_color_primaries = static_cast<AVColorPrimaries> (node->optional_number_child<int>("ColorPrimaries").get_value_or (AVCOL_PRI_UNSPECIFIED));
 	_color_trc = static_cast<AVColorTransferCharacteristic> (
 		node->optional_number_child<int>("ColorTransferCharacteristic").get_value_or (AVCOL_TRC_UNSPECIFIED)
 		);
 	_colorspace = static_cast<AVColorSpace> (node->optional_number_child<int>("Colorspace").get_value_or (AVCOL_SPC_UNSPECIFIED));
+	_bits_per_pixel = static_cast<int> (node->number_child<int> ("BitsPerPixel"));
 
 }
 
@@ -166,6 +166,7 @@ FFmpegContent::as_xml (xmlpp::Node* node) const
 	node->add_child("ColorPrimaries")->add_child_text (raw_convert<string> (_color_primaries));
 	node->add_child("ColorTransferCharacteristic")->add_child_text (raw_convert<string> (_color_trc));
 	node->add_child("Colorspace")->add_child_text (raw_convert<string> (_colorspace));
+	node->add_child("BitsPerPixel")->add_child_text (raw_convert<string> (_bits_per_pixel));
 }
 
 void
@@ -203,6 +204,7 @@ FFmpegContent::examine (shared_ptr<Job> job)
 		_color_primaries = examiner->color_primaries ();
 		_color_trc = examiner->color_trc ();
 		_colorspace = examiner->colorspace ();
+		_bits_per_pixel = examiner->bits_per_pixel ();
 	}
 
 	signal_changed (FFmpegContentProperty::SUBTITLE_STREAMS);
@@ -360,18 +362,22 @@ FFmpegContent::add_properties (list<pair<string, string> >& p) const
 {
 	VideoContent::add_properties (p);
 
-	/* I tried av_*_name for these but they are not the most
-	   nicely formatted.
-	*/
-
-	char const * ranges[] = {
-		_("Unspecified"),
-		_("MPEG (0-219 or equivalent)"),
-		_("JPEG (0-255 or equivalent)")
-	};
-
-	DCPOMATIC_ASSERT (AVCOL_RANGE_NB == 3);
-	p.push_back (make_pair (_("Colour range"), ranges[_color_range]));
+	int const sub = 219 * pow (2, _bits_per_pixel - 8);
+	int const total = pow (2, _bits_per_pixel);
+
+	switch (_color_range) {
+	case AVCOL_RANGE_UNSPECIFIED:
+		p.push_back (make_pair (_("Colour range"), _("Unspecified")));
+		break;
+	case AVCOL_RANGE_MPEG:
+		p.push_back (make_pair (_("Colour range"), String::compose ("Limited (%1-%2)", (total - sub) / 2, (total + sub) / 2)));
+		break;
+	case AVCOL_RANGE_JPEG:
+		p.push_back (make_pair (_("Colour range"), String::compose ("Full (0-total)", (total - sub) / 2, (total + sub) / 2)));
+		break;
+	default:
+		DCPOMATIC_ASSERT (false);
+	}
 
 	char const * primaries[] = {
 		_("Unspecified"),
@@ -427,4 +433,6 @@ FFmpegContent::add_properties (list<pair<string, string> >& p) const
 
 	DCPOMATIC_ASSERT (AVCOL_SPC_NB == 11);
 	p.push_back (make_pair (_("Colourspace"), spaces[_colorspace]));
+
+	p.push_back (make_pair (_("Bits per pixel"), raw_convert<string> (_bits_per_pixel)));
 }
diff --git a/src/lib/ffmpeg_content.h b/src/lib/ffmpeg_content.h
index 05f6cebb6..b2a492e68 100644
--- a/src/lib/ffmpeg_content.h
+++ b/src/lib/ffmpeg_content.h
@@ -122,6 +122,7 @@ private:
 	AVColorPrimaries _color_primaries;
 	AVColorTransferCharacteristic _color_trc;
 	AVColorSpace _colorspace;
+	int _bits_per_pixel;
 };
 
 #endif
diff --git a/src/lib/ffmpeg_examiner.cc b/src/lib/ffmpeg_examiner.cc
index 16a89faa7..f4b650eee 100644
--- a/src/lib/ffmpeg_examiner.cc
+++ b/src/lib/ffmpeg_examiner.cc
@@ -20,6 +20,8 @@
 extern "C" {
 #include <libavcodec/avcodec.h>
 #include <libavformat/avformat.h>
+#include <libavutil/pixfmt.h>
+#include <libavutil/pixdesc.h>
 }
 #include "ffmpeg_examiner.h"
 #include "ffmpeg_content.h"
@@ -275,3 +277,9 @@ FFmpegExaminer::stream_name (AVStream* s) const
 
 	return n.str ();
 }
+
+int
+FFmpegExaminer::bits_per_pixel () const
+{
+	return av_get_bits_per_pixel (av_pix_fmt_desc_get (video_codec_context()->pix_fmt));
+}
diff --git a/src/lib/ffmpeg_examiner.h b/src/lib/ffmpeg_examiner.h
index f5ee95acf..795a9c6ff 100644
--- a/src/lib/ffmpeg_examiner.h
+++ b/src/lib/ffmpeg_examiner.h
@@ -64,6 +64,8 @@ public:
 		return video_codec_context()->colorspace;
 	}
 
+	int bits_per_pixel () const;
+
 private:
 	void video_packet (AVCodecContext *);
 	void audio_packet (AVCodecContext *, boost::shared_ptr<FFmpegAudioStream>);
-- 
2.30.2