Various fixes to allow independent x and y scaling of text subs (#489).

diff --git a/ChangeLog b/ChangeLog
index 55836c9416f4db26836014e547d6215d07d5be1a..820342dacc61b6f7117c95adff20fe14e4fc77bc 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2015-06-03  Carl Hetherington  <cth@carlh.net>
+
+       * Various fixes to subtitle rendering, including independent
+       x and y scale of text subs (#489).
+
 2015-06-02  c.hetherington  <cth@carlh.net>
 
        * Allow use of all content audio streams, not just

diff --git a/cscript b/cscript
index 2ac578dc91b6bdbe54ae06005b9502c8a5343bd3..ee9c586ee3fc89bcc0a05d50547350ed0df0472b 100644 (file)
--- a/cscript
+++ b/cscript
@@ -207,7 +207,7 @@ def make_spec(filename, version, target):
 
 def dependencies(target):
     return (('ffmpeg-cdist', '0492ad2'),
-            ('libdcp', '484a900'),
+            ('libdcp', '47b52fb'),
             ('libsub', 'f66b11f'))
 
 def configure_options(target):

diff --git a/src/lib/player.cc b/src/lib/player.cc
index ac5a705708c7db2d3227937f98b9593d372fb83a..f53bf68d267602b0b31607de210d7fae1c7d36de 100644 (file)
--- a/src/lib/player.cc
+++ b/src/lib/player.cc
@@ -63,6 +63,7 @@ using std::vector;
 using std::pair;
 using std::map;
 using std::make_pair;
+using std::copy;
 using boost::shared_ptr;
 using boost::weak_ptr;
 using boost::dynamic_pointer_cast;
@@ -385,7 +386,8 @@ Player::get_video (DCPTime time, bool accurate)
 
        /* Text subtitles (rendered to an image) */
        if (!ps.text.empty ()) {
-               sub_images.push_back (render_subtitles (ps.text, _video_container_size));
+               list<PositionImage> s = render_subtitles (ps.text, _video_container_size);
+               copy (s.begin (), s.end (), back_inserter (sub_images));
        }
 
        if (!sub_images.empty ()) {
@@ -585,7 +587,13 @@ Player::get_subtitles (DCPTime time, DCPTime length, bool starting)
                BOOST_FOREACH (ContentTextSubtitle& ts, text) {
                        BOOST_FOREACH (dcp::SubtitleString& s, ts.subs) {
                                s.set_v_position (s.v_position() + subtitle_content->subtitle_y_offset ());
-                               s.set_size (s.size() * max (subtitle_content->subtitle_x_scale(), subtitle_content->subtitle_y_scale()));
+                               float const xs = subtitle_content->subtitle_x_scale();
+                               float const ys = subtitle_content->subtitle_y_scale();
+                               float const average = s.size() * (xs + ys) / 2;
+                               s.set_size (average);
+                               if (fabs (1.0 - xs / ys) > dcp::ASPECT_ADJUST_EPSILON) {
+                                       s.set_aspect_adjust (xs / ys);
+                               }
                                ps.text.push_back (s);
                        }
                }

diff --git a/src/lib/render_subtitles.cc b/src/lib/render_subtitles.cc
index 9620eacbf5c58ebe4a3dc847262067c6802ea54e..8f8958868ae2743f99eb0806bc7fd58d365688d9 100644 (file)
--- a/src/lib/render_subtitles.cc
+++ b/src/lib/render_subtitles.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2014 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2014-2015 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
@@ -17,11 +17,12 @@
 
 */
 
-#include <cairomm/cairomm.h>
-#include <pangomm.h>
 #include "render_subtitles.h"
 #include "types.h"
 #include "image.h"
+#include <cairomm/cairomm.h>
+#include <pangomm.h>
+#include <boost/foreach.hpp>
 
 using std::list;
 using std::cout;
@@ -32,39 +33,36 @@ using std::pair;
 using boost::shared_ptr;
 using boost::optional;
 
-static int
-calculate_position (dcp::VAlign v_align, double v_position, int target_height, int offset)
+static PositionImage
+render_subtitle (dcp::SubtitleString const & subtitle, dcp::Size target)
 {
-       switch (v_align) {
-       case dcp::TOP:
-               return v_position * target_height - offset;
-       case dcp::CENTER:
-               return (0.5 + v_position) * target_height - offset;
-       case dcp::BOTTOM:
-               return (1.0 - v_position) * target_height - offset;
+       /* Calculate x and y scale factors.  These are only used to stretch
+          the font away from its normal aspect ratio.
+       */
+       float xscale = 1;
+       float yscale = 1;
+       if (fabs (subtitle.aspect_adjust() - 1.0) > dcp::ASPECT_ADJUST_EPSILON) {
+               if (subtitle.aspect_adjust() < 1) {
+                       xscale = max (0.25f, subtitle.aspect_adjust ());
+                       yscale = 1;
+               } else {
+                       xscale = 1;
+                       yscale = 1 / min (4.0f, subtitle.aspect_adjust ());
+               }
        }
 
-       return 0;
-}
-
-PositionImage
-render_subtitles (list<dcp::SubtitleString> subtitles, dcp::Size target)
-{
-       /* Estimate height that the subtitle image needs to be */
-       optional<int> top;
-       optional<int> bottom;
-       for (list<dcp::SubtitleString>::const_iterator i = subtitles.begin(); i != subtitles.end(); ++i) {
-               int const b = calculate_position (i->v_align(), i->v_position(), target.height, 0);
-               int const t = b - i->size() * target.height / (11 * 72);
-
-               top = min (top.get_value_or (t), t);
-               bottom = max (bottom.get_value_or (b), b);
-       }
+       /* Make an empty bitmap as wide as target and at
+          least tall enough for this subtitle.
+       */
 
-       top = top.get() - 32;
-       bottom = bottom.get() + 32;
+       /* Basic guess on height... */
+       int height = subtitle.size() * target.height / (11 * 72);
+       /* ...scaled... */
+       height *= yscale;
+       /* ...and add a bit more for luck */
+       height += target.height / 11;
 
-       shared_ptr<Image> image (new Image (PIX_FMT_RGBA, dcp::Size (target.width, bottom.get() - top.get ()), false));
+       shared_ptr<Image> image (new Image (PIX_FMT_RGBA, dcp::Size (target.width, height), false));
        image->make_black ();
 
        Cairo::RefPtr<Cairo::ImageSurface> surface = Cairo::ImageSurface::create (
@@ -78,57 +76,83 @@ render_subtitles (list<dcp::SubtitleString> subtitles, dcp::Size target)
        Cairo::RefPtr<Cairo::Context> context = Cairo::Context::create (surface);
        Glib::RefPtr<Pango::Layout> layout = Pango::Layout::create (context);
 
-       layout->set_width (image->size().width * PANGO_SCALE);
-       layout->set_alignment (Pango::ALIGN_CENTER);
+       layout->set_alignment (Pango::ALIGN_LEFT);
 
        context->set_line_width (1);
 
-       for (list<dcp::SubtitleString>::const_iterator i = subtitles.begin(); i != subtitles.end(); ++i) {
-               Pango::FontDescription font (i->font().get_value_or ("Arial"));
-               font.set_absolute_size (i->size_in_pixels (target.height) * PANGO_SCALE);
-               if (i->italic ()) {
-                       font.set_style (Pango::STYLE_ITALIC);
-               }
-               layout->set_font_description (font);
-               layout->set_text (i->text ());
+       /* Render the subtitle at the top left-hand corner of image */
 
-               /* Compute fade factor */
-               /* XXX */
-               float fade_factor = 1;
+       Pango::FontDescription font (subtitle.font().get_value_or ("Arial"));
+       font.set_absolute_size (subtitle.size_in_pixels (target.height) * PANGO_SCALE);
+       if (subtitle.italic ()) {
+               font.set_style (Pango::STYLE_ITALIC);
+       }
+       layout->set_font_description (font);
+       layout->set_text (subtitle.text ());
+       
+       /* Compute fade factor */
+       /* XXX */
+       float fade_factor = 1;
 
-               layout->update_from_cairo_context (context);
+       layout->update_from_cairo_context (context);
                
-               /* Work out position */
-
-               int const x = 0;
-               int const y = calculate_position (i->v_align (), i->v_position (), target.height, (layout->get_baseline() / PANGO_SCALE) + top.get ());
-
-               if (i->effect() == dcp::SHADOW) {
-                       /* Drop-shadow effect */
-                       dcp::Colour const ec = i->effect_colour ();
-                       context->set_source_rgba (float(ec.r) / 255, float(ec.g) / 255, float(ec.b) / 255, fade_factor);
-                       context->move_to (x + 4, y + 4);
-                       layout->add_to_cairo_context (context);
-                       context->fill ();
-               }
+       context->scale (xscale, yscale);
 
-               /* The actual subtitle */
-               context->move_to (x, y);
-               dcp::Colour const c = i->colour ();
-               context->set_source_rgba (float(c.r) / 255, float(c.g) / 255, float(c.b) / 255, fade_factor);
+       if (subtitle.effect() == dcp::SHADOW) {
+               /* Drop-shadow effect */
+               dcp::Colour const ec = subtitle.effect_colour ();
+               context->set_source_rgba (float(ec.r) / 255, float(ec.g) / 255, float(ec.b) / 255, fade_factor);
+               context->move_to (4, 4);
                layout->add_to_cairo_context (context);
                context->fill ();
+       }
 
-               if (i->effect() == dcp::BORDER) {
-                       /* Border effect */
-                       context->move_to (x, y);
-                       dcp::Colour ec = i->effect_colour ();
-                       context->set_source_rgba (float(ec.r) / 255, float(ec.g) / 255, float(ec.b) / 255, fade_factor);
-                       layout->add_to_cairo_context (context);
-                       context->stroke ();
-               }
+       /* The actual subtitle */
+
+       dcp::Colour const c = subtitle.colour ();
+       context->set_source_rgba (float(c.r) / 255, float(c.g) / 255, float(c.b) / 255, fade_factor);
+       context->move_to (0, 0);
+       layout->add_to_cairo_context (context);
+       context->fill ();
+
+       if (subtitle.effect() == dcp::BORDER) {
+               /* Border effect */
+               dcp::Colour ec = subtitle.effect_colour ();
+               context->set_source_rgba (float(ec.r) / 255, float(ec.g) / 255, float(ec.b) / 255, fade_factor);
+               context->move_to (0, 0);
+               layout->add_to_cairo_context (context);
+               context->stroke ();
+       }
+       
+       int layout_width;
+       int layout_height;
+       layout->get_size (layout_width, layout_height);
+
+       int y = 0;
+       switch (subtitle.v_align ()) {
+       case dcp::TOP:
+               /* v_position is distance between top of frame and top of subtitle */
+               y = subtitle.v_position() * target.height;
+               break;
+       case dcp::CENTER:
+               /* v_position is distance between centre of frame and centre of subtitle */
+               y = 0.5 + subtitle.v_position() * target.height - (layout_height / (PANGO_SCALE * 2));
+               break;
+       case dcp::BOTTOM:
+               /* v_position is distance between bottom of frame and bottom of subtitle */
+               y = (1.0 - subtitle.v_position()) * target.height - layout_height / PANGO_SCALE;
+               break;
        }
 
-       return PositionImage (image, Position<int> (0, top.get ()));
+       return PositionImage (image, Position<int> ((image->size().width - layout_width * xscale / PANGO_SCALE) / 2, y));
 }
 
+list<PositionImage>
+render_subtitles (list<dcp::SubtitleString> subtitles, dcp::Size target)
+{
+       list<PositionImage> images;
+       BOOST_FOREACH (dcp::SubtitleString const & i, subtitles) {
+               images.push_back (render_subtitle (i, target));
+       }
+       return images;
+}

diff --git a/src/lib/render_subtitles.h b/src/lib/render_subtitles.h
index 218b866e95cd238bcc96307b5ed0720267d52d43..dbde8011594553b2dd2cf05ca96da4ebed42747e 100644 (file)
--- a/src/lib/render_subtitles.h
+++ b/src/lib/render_subtitles.h
@@ -21,4 +21,4 @@
 #include <dcp/subtitle_string.h>
 #include <dcp/util.h>
 
-PositionImage render_subtitles (std::list<dcp::SubtitleString>, dcp::Size);
+std::list<PositionImage> render_subtitles (std::list<dcp::SubtitleString>, dcp::Size);

diff --git a/src/lib/subrip_decoder.cc b/src/lib/subrip_decoder.cc
index 6ed2e5254fb5c9be4847fd00c3df4eb31a42b865..dae2e4ab755d8085114b137a2ed83b7b0a9ba187 100644 (file)
--- a/src/lib/subrip_decoder.cc
+++ b/src/lib/subrip_decoder.cc
@@ -65,6 +65,7 @@ SubRipDecoder::pass (PassReason)
                                        j->italic,
                                        dcp::Colour (255, 255, 255),
                                        j->font_size.points (72 * 11),
+                                       1.0,
                                        dcp::Time (_subtitles[_next].from.all_as_seconds()),
                                        dcp::Time (_subtitles[_next].to.all_as_seconds()),
                                        i->vertical_position.line.get() * (1.5 / 22) + 0.8,