NAME

       SReview::Video::ProfileFactory - Create an output profile from an input video.

SYNOPSIS

           use SReview::Video;
           use SReview::Videopipe;
           use SReview::Video::ProfileFactory;

           package SReview::Video::Profile::myprofile;
           use Moose;
           extends SReview::Video::Profile::webm;

           has '+audio_samplerate' => (
               builder => '_probe_my_audiorate',
           );

           has '+audio_codec' => (
               default => 'vorbis',
           );

           sub _probe_exten {
               return 'my.webm',
           }

           sub _probe_my_audiorate {
               my $self = shift;
               return $self->reference->audio_samplerate / 2;
           }

           no Moose;

           package main;

           my $input = SReview::Video->new(url => "foo.mp4");
           my $profile = SReview::Video::ProfileFactory->create("myprofile", $input);
           my $output = SReview::Video->new(url => "foo." . $profile->exten, reference => $profile);
           SReview::Videopipe->new(inputs => [$input], output => $output)->run();

DESCRIPTION

       "SReview::Video::Profile::Base" is a subclass of SReview::Video, but with a number of the
       probing methods overridden so that they return values that are not in line with the
       reference of the given video.

       The "SReview::Video::ProfileFactory"'s "create" method is a simple helper to:

       •   ensure that the relevant "SReview::Video::Profile::profile" module has been loaded

       •   create an "SReview::Video" subclass of the right type, with reference set to the
           passed input "SReview::Video" object.

CREATING NEW PROFILES

       It is possible to create a new profile by extending an existing one. The "myprofile"
       profile in the above example shows how to do so. Any property that is known by
       SReview::Video can be overridden in the manner given.

       To create a new profile, one can use the "extra_profiles" configuration setting; however,
       profiles created in this manner can only hardcode values, and cannot vary any parameters
       based on the input file. To create a profile that can do so, when the new profile just
       changes a minor detail of an existing profile, extend that profile and change the detail
       which you want to change. To create a new profile from scratch, extend the "Base" profile
       (see below).

PRE-EXISTING PROFILES

       The following profiles are defined by "SReview::Video::ProfileFactory":

   Base
       This profile serves as a base class for the other profiles. It should not be used
       directly.

       It adds the extension, and defaults the pixel format to yuv420p.

   vp9
       Produces a video in WebM/VP9 format, using the quality/bitrate settings recommended by
       Google on <https://developers.google.com/media/vp9/>, and with OPUS audio. Produces files
       with the "vp9.webm" extension.

       Audio settings are hardcoded to 48KHz sampling rate, 128k bits per second.

   vp8
       Produces a video in WebM/VP8 format. Since no similar recommendations for VP8 exist as do
       for VP9, no explicit quality or bitrate settings are configured in this profile. The
       libvpx video codec is selected, and the libvorbis one for audio.

       The audio bitrate is explicitly left to ffmpeg defaults; the extension is set to
       "vp8.webm"

   webm
       This profile subclasses from the "vp9" profile, and only changes the extension to plain
       "webm" instead of "vp9.webm".

       Additionally, if a future version of WebM is ever defined, then when SReview gains support
       for that version of WebM, this class will become a subclass of that class instead.

   vp8_lq
       This profile subclasses from the "vp8" profile. The extension is set to "lq.webm". In
       addition to the changes made by the "vp8" profile, this profile also rescales the video to
       a fraction of the original; that is, the height and width of the video are both divided by
       8.

SEE ALSO

       SReview::Video