IE11 não está jogando o arquivo mp4

Eu estou usando o ffmpeg para converter um fluxo RTSP público disponível gratuitamente para um arquivo mp4. Eu posso reproduzir o arquivo muito bem no Chrome usando um cliente de vídeo HTML5 padrão em uma máquina com Windows 7, mas não no IE11. Alguma idéia porque o mp4 não vai jogar no IE11?

ffmpeg -i rtsp://dmzosx001.dpa.act.gov.au/medium -acodec copy 
-vcodec copy -f mp4 -movflags frag_keyframe+empty_moov 
-reset_timestamps 1 -vsync 1 -flags global_header -bsf:v dump_extra -y output.mp4

Eu forneci o arquivo mp4 online. A URL do arquivo mp4 é http://184.173.147.99:3000/stream Aqui está o cliente HTML5 padrão que abro no IE11

<!DOCTYPE html>
<html>
  <head>
    <title>Video Test</title>
  </head>
  <body>
    <video id="video" autoplay="autoplay" width="640px" height="480px">  
      <source src="http://184.173.147.99:3000/stream" type="video/mp4" />
            Your browser doesn't appear to support the HTML5 <code>&lt;video&gt;</code> element.  
    </video>
  </body>
</html>

O seguinte é impresso no console como saída do programa ffmpeg

  Input #0, rtsp, from 'rtsp://dmzosx001.dpa.act.gov.au/medium':
  Metadata:
    title           : Wirecast
  Duration: N/A, start: 0.000000, bitrate: N/A
    Stream #0:0: Audio: aac, 32000 Hz, stereo, fltp
    Stream #0:1: Video: h264 (Main), yuv420p(tv, smpte170m), 320x240, 25 tbr, 90
k tbn, 180k tbc
Output #0, mp4, to 'output.mp4':
  Metadata:
    title           : Wirecast
    encoder         : Lavf55.33.100
    Stream #0:0: Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 320x240, q=2-31,
 90k tbn, 90k tbc
    Stream #0:1: Audio: aac ([64][0][0][0] / 0x0040), 32000 Hz, stereo
Stream mapping:
  Stream #0:1 -> #0:0 (copy)
  Stream #0:0 -> #0:1 (copy)
Press [q] to stop, [?] for help
[NULL @ 0x2436180] RTP: missed 1 packets
frame=  106 fps=0.0 q=-1.0 size=     165kB time=00:00:04.71 bitrate= 286.5kbits/
frame=  118 fps=115 q=-1.0 size=     165kB time=00:00:05.19 bitrate= 260.0kbits/
frame=  131 fps= 85 q=-1.0 size=     206kB time=00:00:05.71 bitrate= 295.2kbits/
frame=  144 fps= 70 q=-1.0 size=     206kB time=00:00:06.23 bitrate= 270.6kbits/
frame=  158 fps= 61 q=-1.0 size=     247kB time=00:00:06.79 bitrate= 297.8kbits/
frame=  171 fps= 55 q=-1.0 size=     247kB time=00:00:07.31 bitrate= 276.6kbits/
frame=  182 fps= 50 q=-1.0 size=     288kB time=00:00:07.75 bitrate= 304.3kbits/
frame=  197 fps= 47 q=-1.0 size=     288kB time=00:00:08.35 bitrate= 282.5kbits/
frame=  210 fps= 45 q=-1.0 size=     330kB time=00:00:08.87 bitrate= 304.0kbits/
frame=  223 fps= 43 q=-1.0 size=     330kB time=00:00:09.39 bitrate= 287.2kbits/
frame=  234 fps= 41 q=-1.0 size=     371kB time=00:00:09.85 bitrate= 308.0kbits/
frame=  248 fps= 40 q=-1.0 size=     371kB time=00:00:10.40 bitrate= 291.9kbits/
frame=  262 fps= 39 q=-1.0 size=     412kB time=00:00:10.95 bitrate= 307.7kbits/
.......
......

ffmpeg mp4 internet-explorer-11

— Ashish Lal
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