Merge master.

[dcpomatic.git] / src / lib / subtitle.cc

diff --git a/src/lib/subtitle.cc b/src/lib/subtitle.cc
index 01e8cac1396ea62b386cb60e995fbee50a330cd4..7013f1d7d9004a635ac0732a8f77c638f92f6550 100644 (file)
--- a/src/lib/subtitle.cc
+++ b/src/lib/subtitle.cc
@@ -17,34 +17,47 @@
 
 */
 
+/** @file  src/subtitle.cc
+ *  @brief Representations of subtitles.
+ */
+
 #include "subtitle.h"
 #include "image.h"
 #include "exceptions.h"
-#include "film_state.h"
 
-using namespace std;
-using namespace boost;
+#include "i18n.h"
+
+using boost::shared_ptr;
+using libdcp::Size;
 
+/** Construct a TimedSubtitle.  This is a subtitle image, position,
+ *  and a range of time over which it should be shown.
+ *  @param sub AVSubtitle to read.
+ */
 TimedSubtitle::TimedSubtitle (AVSubtitle const & sub)
 {
-       /* subtitle PTS in seconds */
-       float const packet_time = (sub.pts / AV_TIME_BASE) + float (sub.pts % AV_TIME_BASE) / 1e6;
+       assert (sub.num_rects > 0);
+       
+       /* Subtitle PTS in seconds (within the source, not taking into account any of the
+          source that we may have chopped off for the DCP)
+       */
+       double const packet_time = static_cast<double> (sub.pts) / AV_TIME_BASE;
        
        /* hence start time for this sub */
-       _from = packet_time + (double (sub.start_display_time) / 1e3);
-       _to = packet_time + (double (sub.end_display_time) / 1e3);
+       _from = (packet_time + (double (sub.start_display_time) / 1e3)) * TIME_HZ;
+       _to = (packet_time + (double (sub.end_display_time) / 1e3)) * TIME_HZ;
 
        if (sub.num_rects > 1) {
-               throw DecodeError ("multi-part subtitles not yet supported");
+               throw DecodeError (_("multi-part subtitles not yet supported"));
        }
 
        AVSubtitleRect const * rect = sub.rects[0];
 
        if (rect->type != SUBTITLE_BITMAP) {
-               throw DecodeError ("non-bitmap subtitles not yet supported");
+               throw DecodeError (_("non-bitmap subtitles not yet supported"));
        }
        
-       shared_ptr<Image> image (new AlignedImage (PIX_FMT_RGBA, Size (rect->w, rect->h)));
+       shared_ptr<Image> image (new SimpleImage (PIX_FMT_RGBA, libdcp::Size (rect->w, rect->h), true));
 
        /* Start of the first line in the subtitle */
        uint8_t* sub_p = rect->pict.data[0];
@@ -66,27 +79,41 @@ TimedSubtitle::TimedSubtitle (AVSubtitle const & sub)
        _subtitle.reset (new Subtitle (Position (rect->x, rect->y), image));
 }      
 
-/** @param t Time in seconds from the start of the film */
+/** @param t Time from the start of the source */
 bool
-TimedSubtitle::displayed_at (double t) const
+TimedSubtitle::displayed_at (Time t) const
 {
        return t >= _from && t <= _to;
 }
 
+/** Construct a subtitle, which is an image and a position.
+ *  @param p Position within the (uncropped) source frame.
+ *  @param i Image of the subtitle (should be RGBA).
+ */
 Subtitle::Subtitle (Position p, shared_ptr<Image> i)
        : _position (p)
        , _image (i)
 {
 
 }
-       
-Rectangle
+
+/** Given the area of a subtitle, work out the area it should
+ *  take up when its video frame is scaled up, and it is optionally
+ *  itself scaled and offset.
+ *  @param target_x_scale the x scaling of the video frame that the subtitle is in.
+ *  @param target_y_scale the y scaling of the video frame that the subtitle is in.
+ *  @param sub_area The area of the subtitle within the original source.
+ *  @param subtitle_offset y offset to apply to the subtitle position (+ve is down)
+ *  in the coordinate space of the source.
+ *  @param subtitle_scale scaling factor to apply to the subtitle image.
+ */
+dcpomatic::Rect
 subtitle_transformed_area (
        float target_x_scale, float target_y_scale,
-       Rectangle sub_area, int subtitle_offset, float subtitle_scale
+       dcpomatic::Rect sub_area, int subtitle_offset, float subtitle_scale
        )
 {
-       Rectangle tx;
+       dcpomatic::Rect tx;
 
        sub_area.y += subtitle_offset;
 
@@ -108,14 +135,15 @@ subtitle_transformed_area (
         * Combining these two translations gives these expressions.
         */
        
-       tx.x = target_x_scale * (sub_area.x + (sub_area.width * (1 - subtitle_scale) / 2));
-       tx.y = target_y_scale * (sub_area.y + (sub_area.height * (1 - subtitle_scale) / 2));
+       tx.x = rint (target_x_scale * (sub_area.x + (sub_area.width * (1 - subtitle_scale) / 2)));
+       tx.y = rint (target_y_scale * (sub_area.y + (sub_area.height * (1 - subtitle_scale) / 2)));
 
        return tx;
 }
 
-Rectangle
+/** @return area that this subtitle takes up, in the original uncropped source's coordinate space */
+dcpomatic::Rect
 Subtitle::area () const
 {
-       return Rectangle (_position.x, _position.y, _image->size().width, _image->size().height);
+       return dcpomatic::Rect (_position.x, _position.y, _image->size().width, _image->size().height);
 }