MP4(3)               MP4 File Format Library               MP4(3)


NAME
       MP4GetSampleIdFromTime  - Get the sample id of a specified
       time

SYNTAX
       #include <mp4.h>

       MP4SampleId MP4GetSampleIdFromTime(
            MP4FileHandle hFile,
            MP4TrackId trackId,
            MP4Timestamp when,
            bool wantSyncSample = false
       );

ARGUMENTS
       hFile  Specifies the  mp4  file  to  which  the  operation
              applies.

       trackId
              Specifies the track to which the operation applies.

       when   Specifies the time in the track time scale that  is
              desired.

       wantSyncSample
              Specifies if the returned sample id must correspond
              to a sample whose sync/random access flag is  true.


RETURN VALUES
       Upon  success,  the sample id that occurs at the specified
       time. Upon an error, MP4_INVALID_SAMPLE_ID.

DESCRIPTION
       MP4GetSampleIdFromTime returns the sample id of the  track
       sample in which the specified time occurs.

       The  specified time should be in the track time scale. See
       MP4ConvertToTrackTimestamp() for how to map a  time  value
       to this time scale.

       It  is  wise  to  use MP4GetSampleTime() with the returned
       sample id so one can adjust for any difference between the
       specified time and the actual start time of the sample.

       If  the  calling  application  needs  a sample that can be
       accessed  randomly  then  the  'wantSyncSample'   argument
       should be set to true. This could be the case for a player
       that is implementing a positioning function and  needs  to
       be able to start decoding a track from the returned sample
       id.






Cisco Systems Inc.         Version 0.9                          1





MP4(3)               MP4 File Format Library               MP4(3)


SEE ALSO
       MP4(3) MP4GetSampleIdFromEditTime(3)























































Cisco Systems Inc.         Version 0.9                          2