Add PixelQuanta to VideoContent.

11 files changed, 150 insertions, 1 deletions

diff --git a/src/lib/dcp_examiner.h b/src/lib/dcp_examiner.h
index 66f694f72..fd643a754 100644
--- a/src/lib/dcp_examiner.h
+++ b/src/lib/dcp_examiner.h
@@ -62,6 +62,10 @@ public:
 		return VideoRange::FULL;
 	}
 
+	PixelQuanta pixel_quanta () const {
+		return {};
+	}
+
 	std::string name () const {
 		return _name;
 	}
diff --git a/src/lib/ffmpeg_examiner.cc b/src/lib/ffmpeg_examiner.cc
index 853db90be..0a236d836 100644
--- a/src/lib/ffmpeg_examiner.cc
+++ b/src/lib/ffmpeg_examiner.cc
@@ -480,3 +480,12 @@ FFmpegExaminer::range () const
 		return VideoRange::FULL;
 	}
 }
+
+
+PixelQuanta
+FFmpegExaminer::pixel_quanta () const
+{
+	auto const desc = av_pix_fmt_desc_get(video_codec_context()->pix_fmt);
+	return { 1 << desc->log2_chroma_w, 1 << desc->log2_chroma_h };
+}
+
diff --git a/src/lib/ffmpeg_examiner.h b/src/lib/ffmpeg_examiner.h
index 793460f9b..f978eb52b 100644
--- a/src/lib/ffmpeg_examiner.h
+++ b/src/lib/ffmpeg_examiner.h
@@ -57,6 +57,8 @@ public:
 
 	VideoRange range () const;
 
+	PixelQuanta pixel_quanta () const;
+
 	AVColorRange color_range () const {
 		return video_codec_context()->color_range;
 	}
diff --git a/src/lib/image_examiner.h b/src/lib/image_examiner.h
index cad8683a1..0dcdebad0 100644
--- a/src/lib/image_examiner.h
+++ b/src/lib/image_examiner.h
@@ -39,6 +39,10 @@ public:
 	VideoRange range () const {
 		return VideoRange::FULL;
 	}
+	PixelQuanta pixel_quanta () const {
+		/* See ::yuv - we're assuming the image is not YUV and so not subsampled */
+		return {};
+	}
 
 private:
 	std::weak_ptr<const Film> _film;
diff --git a/src/lib/pixel_quanta.cc b/src/lib/pixel_quanta.cc
new file mode 100644
index 000000000..12eea5031
--- /dev/null
+++ b/src/lib/pixel_quanta.cc
@@ -0,0 +1,47 @@
+/*
+    Copyright (C) 2021 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    DCP-o-matic is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#include "pixel_quanta.h"
+#include <dcp/raw_convert.h>
+
+
+PixelQuanta::PixelQuanta (cxml::ConstNodePtr node)
+	: x(node->number_child<int>("X"))
+	, y(node->number_child<int>("Y"))
+{
+
+}
+
+
+void
+PixelQuanta::as_xml (xmlpp::Element* node) const
+{
+	node->add_child("X")->add_child_text(dcp::raw_convert<std::string>(x));
+	node->add_child("Y")->add_child_text(dcp::raw_convert<std::string>(y));
+}
+
+
+PixelQuanta
+max (PixelQuanta const& a, PixelQuanta const& b)
+{
+	return { std::max(a.x, b.x), std::max(a.y, b.y) };
+}
+
diff --git a/src/lib/pixel_quanta.h b/src/lib/pixel_quanta.h
new file mode 100644
index 000000000..e4a03c9d2
--- /dev/null
+++ b/src/lib/pixel_quanta.h
@@ -0,0 +1,63 @@
+/*
+    Copyright (C) 2021 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    DCP-o-matic is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#ifndef DCPOMATIC_PIXEL_QUANTA_H
+#define DCPOMATIC_PIXEL_QUANTA_H
+
+
+#include "warnings.h"
+
+#include <libcxml/cxml.h>
+DCPOMATIC_DISABLE_WARNINGS
+#include <libxml++/libxml++.h>
+DCPOMATIC_ENABLE_WARNINGS
+
+
+class PixelQuanta
+{
+public:
+	PixelQuanta ()
+		: x(1)
+		, y(1)
+	{}
+
+	/** @param x number of pixels that must not be split in the x direction; e.g. if x=2 scale should
+	 *  only happen to multiples of 2 width, and x crop should only happen at multiples of 2 position.
+	 *  @param y similar value for y / height.
+	 */
+	PixelQuanta (int x_, int y_)
+		: x(x_)
+		, y(y_)
+	{}
+
+	PixelQuanta (cxml::ConstNodePtr node);
+
+	void as_xml (xmlpp::Element* node) const;
+
+	int x;
+	int y;
+};
+
+
+PixelQuanta max (PixelQuanta const& a, PixelQuanta const& b);
+
+#endif
+
diff --git a/src/lib/video_content.cc b/src/lib/video_content.cc
index 655b8baf6..bffe2e322 100644
--- a/src/lib/video_content.cc
+++ b/src/lib/video_content.cc
@@ -184,6 +184,10 @@ VideoContent::VideoContent (Content* parent, cxml::ConstNodePtr node, int versio
 		_range = VideoRange::VIDEO;
 	}
 
+	if (auto pixel_quanta = node->optional_node_child("PixelQuanta")) {
+		_pixel_quanta = PixelQuanta(pixel_quanta);
+	}
+
 	auto burnt = node->optional_string_child("BurntSubtitleLanguage");
 	if (burnt) {
 		_burnt_subtitle_language = dcp::LanguageTag (*burnt);
@@ -243,6 +247,8 @@ VideoContent::VideoContent (Content* parent, vector<shared_ptr<Content> > c)
 		if (c[i]->video->yuv ()) {
 			_yuv = true;
 		}
+
+		_pixel_quanta = max(_pixel_quanta, c[i]->video->_pixel_quanta);
 	}
 
 	_use = ref->use ();
@@ -285,6 +291,7 @@ VideoContent::as_xml (xmlpp::Node* node) const
 	node->add_child("FadeIn")->add_child_text (raw_convert<string> (_fade_in));
 	node->add_child("FadeOut")->add_child_text (raw_convert<string> (_fade_out));
 	node->add_child("Range")->add_child_text(_range == VideoRange::FULL ? "full" : "video");
+	_pixel_quanta.as_xml(node->add_child("PixelQuanta"));
 	if (_burnt_subtitle_language) {
 		node->add_child("BurntSubtitleLanguage")->add_child_text(_burnt_subtitle_language->to_string());
 	}
@@ -299,6 +306,7 @@ VideoContent::take_from_examiner (shared_ptr<VideoExaminer> d)
 	auto const ar = d->sample_aspect_ratio ();
 	auto const yuv = d->yuv ();
 	auto const range = d->range ();
+	auto const pixel_quanta = d->pixel_quanta ();
 
 	ContentChangeSignaller cc1 (_parent, VideoContentProperty::SIZE);
 	ContentChangeSignaller cc2 (_parent, ContentProperty::LENGTH);
@@ -311,6 +319,7 @@ VideoContent::take_from_examiner (shared_ptr<VideoExaminer> d)
 		_sample_aspect_ratio = ar;
 		_yuv = yuv;
 		_range = range;
+		_pixel_quanta = pixel_quanta;
 	}
 
 	LOG_GENERAL ("Video length obtained from header as %1 frames", _length);
diff --git a/src/lib/video_content.h b/src/lib/video_content.h
index 0c4649954..de151e145 100644
--- a/src/lib/video_content.h
+++ b/src/lib/video_content.h
@@ -26,6 +26,7 @@
 #include "colour_conversion.h"
 #include "content_part.h"
 #include "dcpomatic_time.h"
+#include "pixel_quanta.h"
 #include "types.h"
 #include "user_property.h"
 #include <dcp/language_tag.h>
@@ -245,6 +246,7 @@ private:
 	/** fade out time in content frames */
 	Frame _fade_out;
 	VideoRange _range;
+	PixelQuanta _pixel_quanta;
 	boost::optional<dcp::LanguageTag> _burnt_subtitle_language;
 };
 
diff --git a/src/lib/video_examiner.h b/src/lib/video_examiner.h
index 4e5c6dc0a..c56530448 100644
--- a/src/lib/video_examiner.h
+++ b/src/lib/video_examiner.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2013-2016 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2013-2021 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -18,14 +18,18 @@
 
 */
 
+
 /** @file  src/lib/video_examiner.h
  *  @brief VideoExaminer class.
  */
 
+
+#include "pixel_quanta.h"
 #include "types.h"
 #include "video_content.h"
 #include <dcp/types.h>
 
+
 /** @class VideoExaminer
  *  @brief Parent for classes which examine video sources and obtain information about them.
  */
@@ -49,4 +53,5 @@ public:
 	/** @return true if this video is in YUV; must not be called if has_video() == false */
 	virtual bool yuv () const = 0;
 	virtual VideoRange range () const = 0;
+	virtual PixelQuanta pixel_quanta () const = 0;
 };
diff --git a/src/lib/video_mxf_examiner.h b/src/lib/video_mxf_examiner.h
index 37badafba..3719d3efc 100644
--- a/src/lib/video_mxf_examiner.h
+++ b/src/lib/video_mxf_examiner.h
@@ -42,6 +42,9 @@ public:
 	VideoRange range () const {
 		return VideoRange::FULL;
 	}
+	PixelQuanta pixel_quanta () const {
+		return {};
+	}
 
 private:
 	std::shared_ptr<dcp::PictureAsset> _asset;
diff --git a/src/lib/wscript b/src/lib/wscript
index 06bb555b2..fd243db68 100644
--- a/src/lib/wscript
+++ b/src/lib/wscript
@@ -133,6 +133,7 @@ sources = """
           log_entry.cc
           mid_side_decoder.cc
           overlaps.cc
+          pixel_quanta.cc
           player.cc
           player_text.cc
           player_video.cc