Rudimentary SSA parser.

5 files changed, 293 insertions, 0 deletions

diff --git a/src/font_size.cc b/src/font_size.cc
index d11ee89..f3e6c89 100644
--- a/src/font_size.cc
+++ b/src/font_size.cc
@@ -40,3 +40,11 @@ FontSize::points (int screen_height_in_points) const
 
 	return _proportional.get() * screen_height_in_points;
 }
+
+FontSize
+FontSize::from_points (int p)
+{
+	FontSize s;
+	s.set_points (p);
+	return s;
+}
diff --git a/src/font_size.h b/src/font_size.h
index 6439c8f..62bbd09 100644
--- a/src/font_size.h
+++ b/src/font_size.h
@@ -52,6 +52,8 @@ public:
 	float proportional (int screen_height_in_points) const;
 	int points (int screen_height_in_points) const;
 
+	static FontSize from_points (int p);
+
 private:
 	/** as a proportion of screen height */
 	boost::optional<float> _proportional;
diff --git a/src/ssa_reader.cc b/src/ssa_reader.cc
new file mode 100644
index 0000000..f3180a7
--- /dev/null
+++ b/src/ssa_reader.cc
@@ -0,0 +1,236 @@
+/*
+    Copyright (C) 2016 Carl Hetherington <cth@carlh.net>
+
+    This program 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.
+
+    This program 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 this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include "ssa_reader.h"
+#include "util.h"
+#include "sub_assert.h"
+#include "raw_convert.h"
+#include "subtitle.h"
+#include <boost/algorithm/string.hpp>
+#include <boost/bind.hpp>
+#include <boost/foreach.hpp>
+#include <sstream>
+#include <vector>
+
+using std::string;
+using std::stringstream;
+using std::vector;
+using std::map;
+using std::cout;
+using boost::optional;
+using boost::function;
+using namespace boost::algorithm;
+using namespace sub;
+
+/** @param s Subtitle string encoded in UTF-8 */
+SSAReader::SSAReader (string const & s)
+{
+	stringstream str (s);
+	this->read (boost::bind (&get_line_stringstream, &str));
+}
+
+/** @param f Subtitle file encoded in UTF-8 */
+SSAReader::SSAReader (FILE* f)
+{
+	this->read (boost::bind (&get_line_file, f));
+}
+
+class Style
+{
+public:
+	Style ()
+		: font_size (24)
+		, primary_colour (255, 255, 255)
+		, bold (false)
+		, italic (false)
+	{}
+
+	Style (string format_line, string style_line)
+		: font_size (24)
+		, primary_colour (255, 255, 255)
+		, bold (false)
+		, italic (false)
+	{
+		vector<string> keys;
+		split (keys, format_line, is_any_of (","));
+		vector<string> style;
+		split (style, style_line, is_any_of (","));
+
+		SUB_ASSERT (!keys.empty());
+		SUB_ASSERT (!style.empty());
+		SUB_ASSERT (keys.size() == style.size());
+
+		for (size_t i = 0; i < style.size(); ++i) {
+			trim (keys[i]);
+			trim (style[i]);
+			if (keys[i] == "Name") {
+				name = style[i];
+			} else if (keys[i] == "Fontname") {
+				font_name = style[i];
+			} else if (keys[i] == "Fontsize") {
+				font_size = raw_convert<int> (style[i]);
+			} else if (keys[i] == "PrimaryColour") {
+				primary_colour = colour (raw_convert<int> (style[i]));
+			} else if (keys[i] == "BackColour") {
+				back_colour = colour (raw_convert<int> (style[i]));
+			} else if (keys[i] == "Bold") {
+				bold = style[i] == "-1";
+			} else if (keys[i] == "Italic") {
+				italic = style[i] == "-1";
+			} else if (keys[i] == "BorderStyle") {
+				if (style[i] == "1") {
+					effect = SHADOW;
+				}
+			}
+		}
+	}
+
+	string name;
+	optional<string> font_name;
+	int font_size;
+	Colour primary_colour;
+	/** outline colour */
+	optional<Colour> back_colour;
+	bool bold;
+	bool italic;
+	optional<Effect> effect;
+
+private:
+	Colour colour (int c) const
+	{
+		return Colour (
+			((c & 0x0000ff) >>  0) / 255.0,
+			((c & 0x00ff00) >>  8) / 255.0,
+			((c & 0xff0000) >> 16) / 255.0
+			);
+	}
+};
+
+Time
+SSAReader::parse_time (string t) const
+{
+	vector<string> bits;
+	split (bits, t, is_any_of (":."));
+	SUB_ASSERT (bits.size() == 4);
+	return Time::from_hms (
+		raw_convert<int> (bits[0]),
+		raw_convert<int> (bits[1]),
+		raw_convert<int> (bits[2]),
+		raw_convert<int> (bits[3]) * 10
+		);
+}
+
+void
+SSAReader::read (function<optional<string> ()> get_line)
+{
+	enum {
+		INFO,
+		STYLES,
+		EVENTS
+	} part = INFO;
+
+	map<string, Style> styles;
+	string style_format_line;
+	vector<string> event_format;
+
+	while (true) {
+		optional<string> line = get_line ();
+		if (!line) {
+			break;
+		}
+
+		trim (*line);
+
+		if (starts_with (*line, ";") || line->empty ()) {
+			continue;
+		}
+
+		if (starts_with (*line, "[")) {
+			/* Section heading */
+			if (line.get() == "[Script Info]") {
+				part = INFO;
+			} else if (line.get() == "[V4 Styles]") {
+				part = STYLES;
+			} else if (line.get() == "[Events]") {
+				part = EVENTS;
+			}
+			continue;
+		}
+
+		size_t const colon = line->find (":");
+		SUB_ASSERT (colon != string::npos);
+		SUB_ASSERT (line->length() > colon + 1);
+		string const type = line->substr (0, colon);
+		string const body = line->substr (colon + 2);
+
+		switch (part) {
+		case INFO:
+			break;
+		case STYLES:
+			if (type == "Format") {
+				style_format_line = body;
+			} else if (type == "Style") {
+				SUB_ASSERT (!style_format_line.empty ());
+				Style s (style_format_line, body);
+				styles[s.name] = s;
+			}
+			break;
+		case EVENTS:
+			if (type == "Format") {
+				split (event_format, body, is_any_of (","));
+				BOOST_FOREACH (string& i, event_format) {
+					trim (i);
+				}
+			} else if (type == "Dialogue") {
+				SUB_ASSERT (!event_format.empty ());
+				vector<string> event;
+				split (event, body, is_any_of (","));
+
+				SUB_ASSERT (!event.empty());
+				SUB_ASSERT (event_format.size() == event.size());
+
+				RawSubtitle sub;
+
+				for (size_t i = 0; i < event.size(); ++i) {
+					trim (event[i]);
+					if (event_format[i] == "Start") {
+						sub.from = parse_time (event[i]);
+					} else if (event_format[i] == "End") {
+						sub.to = parse_time (event[i]);
+					} else if (event_format[i] == "Style") {
+						SUB_ASSERT (styles.find(event[i]) != styles.end());
+						Style style = styles[event[i]];
+						sub.font = style.font_name;
+						sub.font_size = FontSize::from_points (style.font_size);
+						sub.colour = style.primary_colour;
+						sub.effect_colour = style.back_colour;
+						sub.bold = style.bold;
+						sub.italic = style.italic;
+						sub.effect = style.effect;
+					} else if (event_format[i] == "Text") {
+						sub.text = event[i];
+					}
+				}
+
+				_subs.push_back (sub);
+			}
+		}
+
+	}
+}
diff --git a/src/ssa_reader.h b/src/ssa_reader.h
new file mode 100644
index 0000000..0f575ff
--- /dev/null
+++ b/src/ssa_reader.h
@@ -0,0 +1,45 @@
+/*
+    Copyright (C) 2016 Carl Hetherington <cth@carlh.net>
+
+    This program 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.
+
+    This program 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 this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+/** @file  src/ssa_reader.h
+ *  @brief SSAReader class.
+ */
+
+#ifndef LIBSUB_SSA_READER_H
+#define LIBSUB_SSA_READER_H
+
+#include "reader.h"
+#include <boost/function.hpp>
+
+namespace sub {
+
+class SSAReader : public Reader
+{
+public:
+	SSAReader (FILE* f);
+	SSAReader (std::string const & subs);
+
+private:
+	void read (boost::function<boost::optional<std::string> ()> get_line);
+	Time parse_time (std::string t) const;
+};
+
+}
+
+#endif
diff --git a/src/wscript b/src/wscript
index e881a78..9136ea1 100644
--- a/src/wscript
+++ b/src/wscript
@@ -25,6 +25,7 @@ def build(bld):
                  reader.cc
                  reader_factory.cc
                  smpte_dcp_reader.cc
+                 ssa_reader.cc
                  stl_binary_reader.cc
                  stl_binary_tables.cc
                  stl_binary_writer.cc
@@ -54,6 +55,7 @@ def build(bld):
               raw_subtitle.h
               reader.h
               smpte_dcp_reader.h
+              ssa_reader.h
               stl_binary_tables.h
               stl_binary_reader.h
               stl_binary_writer.h