Take care of libavcodec convergence_duration deprecation

This AVPacket field was a hack against the fact that the duration field
was merely an int (too small for things like subtitle durations). Newer
libavcodec drops this field and makes duration 64 bit.

TOOLS/old-configure

@@ -816,6 +816,12 @@ api_statement_check \
     libavutil/pixdesc.h \
     'AVComponentDescriptor d; int x = d.depth'
 
+api_statement_check \
+    "libavcodec 64 bit AVPacket.duration" \
+    HAVE_AV_AVPACKET_INT64_DURATION \
+    libavcodec/avcodec.h \
+    'int x[(int)sizeof(((AVPacket){0}).duration) - 7]'
+
 check_pkg_config "libavfilter" $_libavfilter LIBAVFILTER 'libavfilter >= 5.0.0'
 
 check_pkg_config "libavdevice" $_libavdevice LIBAVDEVICE 'libavdevice >= 55.0.0'

demux/demux_lavf.c

@@ -882,8 +882,10 @@ static int demux_lavf_fill_buffer(demuxer_t *demux)
     if (pkt->dts != AV_NOPTS_VALUE)
         dp->dts = pkt->dts * av_q2d(st->time_base);
     dp->duration = pkt->duration * av_q2d(st->time_base);
+#if !HAVE_AV_AVPACKET_INT64_DURATION
     if (pkt->convergence_duration > 0)
         dp->duration = pkt->convergence_duration * av_q2d(st->time_base);
+#endif
     dp->pos = pkt->pos;
     dp->keyframe = pkt->flags & AV_PKT_FLAG_KEY;
     if (dp->pts != MP_NOPTS_VALUE) {

sub/sd_lavc_conv.c

@@ -202,7 +202,9 @@ static int parse_webvtt(AVPacket *in, AVPacket *pkt)
 
     pkt->pts = in->pts;
     pkt->duration = in->duration;
+#if !HAVE_AV_AVPACKET_INT64_DURATION
     pkt->convergence_duration = in->convergence_duration;
+#endif
     return 0;
 }
 

wscript

@@ -458,7 +458,13 @@ FFmpeg/Libav libraries. You need at least {0}. Aborting.".format(libav_versions_
         'func': check_statement('libavutil/pixdesc.h',
                                 'AVComponentDescriptor d; int x = d.depth',
                                 use='libav'),
-    }
+    }, {
+        'name': 'av-avpacket-int64-duration',
+        'desc': 'libavcodec 64 bit AVPacket.duration',
+        'func': check_statement('libavcodec/avcodec.h',
+                                'int x[(int)sizeof(((AVPacket){0}).duration) - 7]',
+                                use='libav'),
+    },
 ]
 
 audio_output_features = [