Fix incorrect scaling of DVB subtitles when the picture is not 720x576.

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

diff --git a/src/lib/ffmpeg_decoder.cc b/src/lib/ffmpeg_decoder.cc
index 164785c8368bb0fbffea1a28d468247df4eadf47..253272e9638a3387f529b7d5548eff86321ddaf6 100644 (file)
--- a/src/lib/ffmpeg_decoder.cc
+++ b/src/lib/ffmpeg_decoder.cc
@@ -40,6 +40,7 @@
 #include "audio_decoder.h"
 #include "compose.hpp"
 #include "subtitle_content.h"
+#include "audio_content.h"
 #include <dcp/subtitle_string.h>
 #include <sub/ssa_reader.h>
 #include <sub/subtitle.h>
@@ -73,6 +74,8 @@ using std::map;
 using boost::shared_ptr;
 using boost::is_any_of;
 using boost::split;
+using boost::optional;
+using boost::dynamic_pointer_cast;
 using dcp::Size;
 
 FFmpegDecoder::FFmpegDecoder (shared_ptr<const FFmpegContent> c, shared_ptr<Log> log)
@@ -134,7 +137,7 @@ FFmpegDecoder::pass (PassReason reason, bool accurate)
                        /* Maybe we should fail here, but for now we'll just finish off instead */
                        char buf[256];
                        av_strerror (r, buf, sizeof(buf));
-                       LOG_ERROR (N_("error on av_read_frame (%1) (%2)"), buf, r);
+                       LOG_ERROR (N_("error on av_read_frame (%1) (%2)"), &buf[0], r);
                }
 
                flush ();
@@ -326,7 +329,18 @@ FFmpegDecoder::seek (ContentTime time, bool accurate)
           http://www.mjbshaw.com/2012/04/seeking-in-ffmpeg-know-your-timestamp.html
        */
 
-       DCPOMATIC_ASSERT (_video_stream);
+       optional<int> stream;
+
+       if (_video_stream) {
+               stream = _video_stream;
+       } else {
+               shared_ptr<FFmpegAudioStream> s = dynamic_pointer_cast<FFmpegAudioStream> (_ffmpeg_content->audio->stream ());
+               if (s) {
+                       stream = s->index (_format_context);
+               }
+       }
+
+       DCPOMATIC_ASSERT (stream);
 
        ContentTime u = time - _pts_offset;
        if (u < ContentTime ()) {
@@ -334,12 +348,14 @@ FFmpegDecoder::seek (ContentTime time, bool accurate)
        }
        av_seek_frame (
                _format_context,
-               _video_stream.get(),
-               u.seconds() / av_q2d (_format_context->streams[_video_stream.get()]->time_base),
+               stream.get(),
+               u.seconds() / av_q2d (_format_context->streams[stream.get()]->time_base),
                AVSEEK_FLAG_BACKWARD
                );
 
-       avcodec_flush_buffers (video_codec_context());
+       if (video_codec_context ()) {
+               avcodec_flush_buffers (video_codec_context());
+       }
 
        /* XXX: should be flushing audio buffers? */
 
@@ -376,7 +392,7 @@ FFmpegDecoder::decode_audio_packet ()
                if (decode_result < 0) {
                        /* avcodec_decode_audio4 can sometimes return an error even though it has decoded
                           some valid data; for example dca_subframe_footer can return AVERROR_INVALIDDATA
-                          if it overreads the auxiliary data.  ffplay carries on if frame_finished is true,
+                          if it overreads the auxiliary data.  ffplay carries on if frame_finished is true,
                           even in the face of such an error, so I think we should too.
 
                           Returning from the method here caused mantis #352.
@@ -405,7 +421,14 @@ FFmpegDecoder::decode_audio_packet ()
                                ct += ContentTime::from_frames (remove, (*stream)->frame_rate ());
                        }
 
-                       if (data->frames() > 0) {
+                       if (ct < ContentTime()) {
+                               LOG_WARNING ("Crazy timestamp %s", to_string (ct));
+                       }
+
+                       update_position (ct);
+
+                       /* Give this data provided there is some, and its time is sane */
+                       if (ct >= ContentTime() && data->frames() > 0) {
                                audio->give (*stream, data, ct);
                        }
                }
@@ -455,6 +478,7 @@ FFmpegDecoder::decode_video_packet ()
                                shared_ptr<ImageProxy> (new RawImageProxy (image)),
                                llrint (pts * _ffmpeg_content->active_video_frame_rate ())
                                );
+                       update_position (ContentTime::from_seconds (pts));
                } else {
                        LOG_WARNING_NC ("Dropping frame without PTS");
                }
@@ -485,6 +509,7 @@ FFmpegDecoder::decode_subtitle_packet ()
        FFmpegSubtitlePeriod sub_period = subtitle_period (sub);
        ContentTimePeriod period;
        period.from = sub_period.from + _pts_offset;
+       update_position (period.from);
        if (sub_period.to) {
                /* We already know the subtitle period `to' time */
                period.to = sub_period.to.get() + _pts_offset;
@@ -587,12 +612,13 @@ FFmpegDecoder::decode_bitmap_subtitle (AVSubtitleRect const * rect, ContentTimeP
                out_p += image->stride()[0] / sizeof (uint32_t);
        }
 
-       dcp::Size const vs = _ffmpeg_content->video->size ();
+       int const target_width = subtitle_codec_context()->width;
+       int const target_height = subtitle_codec_context()->height;
        dcpomatic::Rect<double> const scaled_rect (
-               static_cast<double> (rect->x) / vs.width,
-               static_cast<double> (rect->y) / vs.height,
-               static_cast<double> (rect->w) / vs.width,
-               static_cast<double> (rect->h) / vs.height
+               static_cast<double> (rect->x) / target_width,
+               static_cast<double> (rect->y) / target_height,
+               static_cast<double> (rect->w) / target_width,
+               static_cast<double> (rect->h) / target_height
                );
 
        subtitle->give_image (period, image, scaled_rect);
@@ -618,3 +644,16 @@ FFmpegDecoder::decode_ass_subtitle (string ass, ContentTimePeriod period)
                subtitle->give_text (period, i);
        }
 }
+
+void
+FFmpegDecoder::update_position (ContentTime p)
+{
+       /* _position should err on the side of being too big, as then there is less
+          chance that we will erroneously decide not to seek when _position > request.
+       */
+       if (!_position) {
+               _position = p;
+       } else {
+               _position = max (*_position, p);
+       }
+}