NAME

       Media::Convert::AvSync - Helper module to fix A/V synchronization issues.

SYNOPSIS

         use Media::Convert::Asset;
         use Media::Convert::AvSync;

         my $input = Media::Convert::Asset->new(url => $input_filename);
         my $output = Media::Convert::Asset->new(url => $output_filename);
         Media::Convert::AvSync->new(input => $input, output => $output, audio_delay => 0.1)->run();

DESCRIPTION

       Media::Convert::AvSync is a higher-level helper module to correct audio/video
       synchronization issues.

       It does this by instructing ffmpeg to read the input asset twice (once for audio, once for
       video), and to apply a time offset to the audio stream. This offset may be negative, in
       case audio precedes video.

       Note that after A/V sync correction, the asset file will be reduced in length by twice the
       length of the correction value; this is because otherwise, in the case of audio preceding
       video, the resulting media file would end up with a snippet of audio with no video at the
       start, and one of video with no audio at the end (and vice versa for a correction value
       for video preceding audio).

ATTRIBUTES

       The following attributes are supported by Media::Convert::AvSync:

   input
       The input asset. Must be a Media::Convert::Asset object.

   output
       The output asset. Must be a Media::Convert::Asset object.

   audio_delay
       The delay that should be applied to the audio in the input asset. Should be expressed in
       seconds; may be a fractional and/or negative value.

       Postive values delay the audio; negative values delay the video.