2 Copyright (C) 2014-2021 Carl Hetherington <cth@carlh.net>
4 This file is part of DCP-o-matic.
6 DCP-o-matic is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 DCP-o-matic is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with DCP-o-matic. If not, see <http://www.gnu.org/licenses/>.
23 #include "dcpomatic_assert.h"
26 #include "render_text.h"
30 #include <dcp/raw_convert.h>
31 #include <fontconfig/fontconfig.h>
32 #include <cairomm/cairomm.h>
33 DCPOMATIC_DISABLE_WARNINGS
35 DCPOMATIC_ENABLE_WARNINGS
36 #include <pango/pangocairo.h>
37 #include <boost/algorithm/string.hpp>
45 using std::make_shared;
49 using std::shared_ptr;
51 using namespace dcpomatic;
54 static FcConfig* fc_config = nullptr;
55 static list<pair<boost::filesystem::path, string>> fc_config_fonts;
59 marked_up (list<StringText> subtitles, int target_height, float fade_factor)
63 for (auto const& i: subtitles) {
66 out += "style=\"italic\" ";
69 out += "weight=\"bold\" ";
72 out += "underline=\"single\" ";
74 out += "size=\"" + dcp::raw_convert<string>(i.size_in_pixels(target_height) * 72 * 1024 / 96) + "\" ";
75 /* Between 1-65535 inclusive, apparently... */
76 out += "alpha=\"" + dcp::raw_convert<string>(int(floor(fade_factor * 65534)) + 1) + "\" ";
77 out += "color=\"#" + i.colour().to_rgb_string() + "\">";
87 set_source_rgba (Cairo::RefPtr<Cairo::Context> context, dcp::Colour colour, float fade_factor)
89 context->set_source_rgba (float(colour.r) / 255, float(colour.g) / 255, float(colour.b) / 255, fade_factor);
93 static shared_ptr<Image>
94 create_image (dcp::Size size)
96 /* FFmpeg BGRA means first byte blue, second byte green, third byte red, fourth byte alpha */
97 auto image = make_shared<Image>(AV_PIX_FMT_BGRA, size, Image::Alignment::COMPACT);
103 static Cairo::RefPtr<Cairo::ImageSurface>
104 create_surface (shared_ptr<Image> image)
106 return Cairo::ImageSurface::create (
108 Cairo::FORMAT_ARGB32,
110 image->size().height,
111 /* Cairo ARGB32 means first byte blue, second byte green, third byte red, fourth byte alpha */
112 Cairo::ImageSurface::format_stride_for_width (Cairo::FORMAT_ARGB32, image->size().width)
118 setup_font (StringText const& subtitle, list<shared_ptr<Font>> const& fonts)
121 fc_config = FcInitLoadConfig ();
124 auto font_file = default_font_file ();
126 for (auto i: fonts) {
127 if (i->id() == subtitle.font() && i->file()) {
128 font_file = i->file().get();
132 auto existing = fc_config_fonts.cbegin ();
133 while (existing != fc_config_fonts.end() && existing->first != font_file) {
138 if (existing != fc_config_fonts.end ()) {
139 font_name = existing->second;
141 /* Make this font available to DCP-o-matic */
142 FcConfigAppFontAddFile (fc_config, reinterpret_cast<FcChar8 const *>(font_file.string().c_str()));
143 auto pattern = FcPatternBuild (
144 0, FC_FILE, FcTypeString, font_file.string().c_str(), static_cast<char *>(0)
146 auto object_set = FcObjectSetBuild (FC_FAMILY, FC_STYLE, FC_LANG, FC_FILE, static_cast<char *> (0));
147 auto font_set = FcFontList (fc_config, pattern, object_set);
149 for (int i = 0; i < font_set->nfont; ++i) {
150 FcPattern* font = font_set->fonts[i];
155 FcPatternGetString (font, FC_FILE, 0, &file) == FcResultMatch &&
156 FcPatternGetString (font, FC_FAMILY, 0, &family) == FcResultMatch &&
157 FcPatternGetString (font, FC_STYLE, 0, &style) == FcResultMatch
159 font_name = reinterpret_cast<char const *> (family);
163 FcFontSetDestroy (font_set);
166 FcObjectSetDestroy (object_set);
167 FcPatternDestroy (pattern);
169 fc_config_fonts.push_back (make_pair(font_file, font_name));
172 FcConfigSetCurrent (fc_config);
178 calculate_fade_factor (StringText const& first, DCPTime time, int frame_rate)
180 float fade_factor = 1;
182 /* Round the fade start/end to the nearest frame start. Otherwise if a subtitle starts just after
183 the start of a frame it will be faded out.
185 auto const fade_in_start = DCPTime::from_seconds(first.in().as_seconds()).round(frame_rate);
186 auto const fade_in_end = fade_in_start + DCPTime::from_seconds (first.fade_up_time().as_seconds ());
187 auto const fade_out_end = DCPTime::from_seconds (first.out().as_seconds()).round(frame_rate);
188 auto const fade_out_start = fade_out_end - DCPTime::from_seconds (first.fade_down_time().as_seconds ());
190 if (fade_in_start <= time && time <= fade_in_end && fade_in_start != fade_in_end) {
191 fade_factor *= DCPTime(time - fade_in_start).seconds() / DCPTime(fade_in_end - fade_in_start).seconds();
193 if (fade_out_start <= time && time <= fade_out_end && fade_out_start != fade_out_end) {
194 fade_factor *= 1 - DCPTime(time - fade_out_start).seconds() / DCPTime(fade_out_end - fade_out_start).seconds();
196 if (time < fade_in_start || time > fade_out_end) {
205 x_position (StringText const& first, int target_width, int layout_width)
208 switch (first.h_align()) {
209 case dcp::HAlign::LEFT:
210 /* h_position is distance between left of frame and left of subtitle */
211 x = first.h_position() * target_width;
213 case dcp::HAlign::CENTER:
214 /* h_position is distance between centre of frame and centre of subtitle */
215 x = (0.5 + first.h_position()) * target_width - layout_width / 2;
217 case dcp::HAlign::RIGHT:
218 /* h_position is distance between right of frame and right of subtitle */
219 x = (1.0 - first.h_position()) * target_width - layout_width;
228 y_position (StringText const& first, int target_height, int layout_height)
231 switch (first.v_align()) {
232 case dcp::VAlign::TOP:
233 /* SMPTE says that v_position is the distance between top
234 of frame and top of subtitle, but this doesn't always seem to be
235 the case in practice; Gunnar Ásgeirsson's Dolby server appears
236 to put VAlign::TOP subs with v_position as the distance between top
237 of frame and bottom of subtitle.
239 y = first.v_position() * target_height - layout_height;
241 case dcp::VAlign::CENTER:
242 /* v_position is distance between centre of frame and centre of subtitle */
243 y = (0.5 + first.v_position()) * target_height - layout_height / 2;
245 case dcp::VAlign::BOTTOM:
246 /* v_position is distance between bottom of frame and bottom of subtitle */
247 y = (1.0 - first.v_position()) * target_height - layout_height;
256 setup_layout (Glib::RefPtr<Pango::Layout> layout, string font_name, string markup)
258 layout->set_alignment (Pango::ALIGN_LEFT);
259 Pango::FontDescription font (font_name);
260 layout->set_font_description (font);
261 layout->set_markup (markup);
265 /** Create a Pango layout using a dummy context which we can use to calculate the size
266 * of the text we will render. Then we can transfer the layout over to the real context
267 * for the actual render.
269 static Glib::RefPtr<Pango::Layout>
272 auto c_font_map = pango_cairo_font_map_new ();
273 DCPOMATIC_ASSERT (c_font_map);
274 auto font_map = Glib::wrap (c_font_map);
275 auto c_context = pango_font_map_create_context (c_font_map);
276 DCPOMATIC_ASSERT (c_context);
277 auto context = Glib::wrap (c_context);
278 return Pango::Layout::create (context);
282 /** @param subtitles A list of subtitles that are all on the same line,
283 * at the same time and with the same fade in/out.
286 render_line (list<StringText> subtitles, list<shared_ptr<Font>> fonts, dcp::Size target, DCPTime time, int frame_rate)
288 /* XXX: this method can only handle italic / bold changes mid-line,
292 DCPOMATIC_ASSERT (!subtitles.empty ());
293 auto const& first = subtitles.front ();
295 auto const font_name = setup_font (first, fonts);
296 auto const fade_factor = calculate_fade_factor (first, time, frame_rate);
297 auto const markup = marked_up (subtitles, target.height, fade_factor);
298 auto layout = create_layout ();
299 setup_layout (layout, font_name, markup);
301 layout->get_pixel_size (size.width, size.height);
303 /* Calculate x and y scale factors. These are only used to stretch
304 the font away from its normal aspect ratio.
308 if (fabs (first.aspect_adjust() - 1.0) > dcp::ASPECT_ADJUST_EPSILON) {
309 if (first.aspect_adjust() < 1) {
310 x_scale = max (0.25f, first.aspect_adjust ());
314 y_scale = 1 / min (4.0f, first.aspect_adjust ());
318 auto const border_width = first.effect() == dcp::Effect::BORDER ? (first.outline_width * target.width / 2048.0) : 0;
319 size.width += 2 * ceil (border_width);
320 size.height += 2 * ceil (border_width);
322 size.width *= x_scale;
323 size.height *= y_scale;
325 /* Shuffle the subtitle over by the border width (if we have any) so it's not cut off */
326 int const x_offset = ceil (border_width);
327 /* Move down a bit so that accents on capital letters can be seen */
328 int const y_offset = target.height / 100.0;
330 size.width += x_offset;
331 size.height += y_offset;
333 auto image = create_image (size);
334 auto surface = create_surface (image);
335 auto context = Cairo::Context::create (surface);
337 context->set_line_width (1);
338 context->scale (x_scale, y_scale);
339 layout->update_from_cairo_context (context);
341 if (first.effect() == dcp::Effect::SHADOW) {
342 /* Drop-shadow effect */
343 set_source_rgba (context, first.effect_colour(), fade_factor);
344 context->move_to (x_offset + 4, y_offset + 4);
345 layout->add_to_cairo_context (context);
349 if (first.effect() == dcp::Effect::BORDER) {
351 set_source_rgba (context, first.effect_colour(), fade_factor);
352 context->set_line_width (border_width);
353 context->set_line_join (Cairo::LINE_JOIN_ROUND);
354 context->move_to (x_offset, y_offset);
355 layout->add_to_cairo_context (context);
359 /* The actual subtitle */
361 set_source_rgba (context, first.colour(), fade_factor);
363 context->move_to (x_offset, y_offset);
364 layout->add_to_cairo_context (context);
367 context->set_line_width (0.5);
368 context->move_to (x_offset, y_offset);
369 layout->add_to_cairo_context (context);
372 int const x = x_position (first, target.width, size.width);
373 int const y = y_position (first, target.height, size.height);
374 return PositionImage (image, Position<int>(max (0, x), max(0, y)));
378 /** @param time Time of the frame that these subtitles are going on.
379 * @param target Size of the container that this subtitle will end up in.
380 * @param frame_rate DCP frame rate.
383 render_text (list<StringText> subtitles, list<shared_ptr<Font>> fonts, dcp::Size target, DCPTime time, int frame_rate)
385 list<StringText> pending;
386 list<PositionImage> images;
388 for (auto const& i: subtitles) {
389 if (!pending.empty() && (i.v_align() != pending.back().v_align() || fabs(i.v_position() - pending.back().v_position()) > 1e-4)) {
390 images.push_back (render_line (pending, fonts, target, time, frame_rate));
393 pending.push_back (i);
396 if (!pending.empty()) {
397 images.push_back (render_line (pending, fonts, target, time, frame_rate));