[FFmpeg-trac] #986(avutil:new): windows named pipe seek

FFmpeg trac at avcodec.org
Thu Feb 9 20:52:22 CET 2012

#986: windows named pipe seek
             Reporter:  setosha      |                    Owner:  michael
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:  avutil
              Version:  unspecified  |               Resolution:
             Keywords:  windows      |               Blocked By:
  named pipe seek                    |  Reproduced by developer:  0
             Blocking:               |
Analyzed by developer:  0            |

Comment (by setosha):

 Replying to [comment:8 mjs973]:

 > An .mp4 container is not streamable; the file layout requires seek
 operations. The only way to play one, in general, is to download the
 entire file to memory or local disk.

 Look at YouTube. It works! without saving entire file.

 > Maybe your pipe:0 test only works because your test file is smaller than
 the internal memory cache inside ffmpeg? For a big .mp4 file, your
 architecture will be a problem.

 About mp4 structure. At start it has codec settings and table with stream
 chunks offsets, durations and sizes. May be some metadata. That table is
 only thing that ffmpeg should save while converting. Next placed chunks it
 self. Video and audio "mixed" together to make possible seeking by time.

 > Why don't you use a streaming format?

 We talk about different "streamings". Usualy "streaming" means "you can
 start broadcast before last stream frame captured and packed in data
 stream", but in my case it means "you can continuosly read audio and video
 streams from container without seeks and cache overrun".

 So in my streaming definition mp4 container is good. Thats why pipe:0

 PS. Sorry for my english.

Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/986#comment:9>
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