Merge remote-tracking branch 'qatar/master'

* qatar/master:
  movenc: Indicate that negative timestamps are supported

Merged-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/movenc.c

@@ -4050,7 +4050,7 @@ AVOutputFormat ff_psp_muxer = {
     .write_header      = mov_write_header,
     .write_packet      = mov_write_packet,
     .write_trailer     = mov_write_trailer,
-    .flags             = AVFMT_GLOBALHEADER | AVFMT_ALLOW_FLUSH,
+    .flags             = AVFMT_GLOBALHEADER | AVFMT_ALLOW_FLUSH | AVFMT_TS_NEGATIVE,
     .codec_tag         = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 },
     .priv_class        = &psp_muxer_class,
 };
@@ -4103,7 +4103,7 @@ AVOutputFormat ff_ismv_muxer = {
     .write_header      = mov_write_header,
     .write_packet      = mov_write_packet,
     .write_trailer     = mov_write_trailer,
-    .flags             = AVFMT_GLOBALHEADER | AVFMT_ALLOW_FLUSH,
+    .flags             = AVFMT_GLOBALHEADER | AVFMT_ALLOW_FLUSH | AVFMT_TS_NEGATIVE,
     .codec_tag         = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 },
     .priv_class        = &ismv_muxer_class,
 };