_format.py

"""
ffmpeg_streaming.media
~~~~~~~~~~~~

Video and audio formats


:copyright: (c) 2020 by Amin Yazdanpanah.
:website: https://www.aminyazdanpanah.com
:email: contact@aminyazdanpanah.com
:license: MIT, see LICENSE for more details.
"""
import abc


MULTIPLY_BY_ONE = 1
MULTIPLY_BY_TWO = 2
MULTIPLY_BY_FOUR = 4
MULTIPLY_BY_Eight = 8
MULTIPLY_BY_SIXTEEN = 16
MULTIPLY_BY_THIRTY_TWO = 32


def _verify_codecs(codec, codecs):
    if codec is None:
        return
    elif codec not in codecs:
        ValueError("The codec is not available!")
    else:
        return str(codec)


class Format(abc.ABC):
    """
    @TODO: add documentation
    """
    def __init__(self, video: str, audio: str, **codec_options):
        self.video = video
        self.audio = audio
        self.codec_options = codec_options

    @property
    def all(self) -> dict:
        args = {
            'c:v': self.video,
            'c:a': self.audio,
        }
        args.update(self.get_codec_options())

        return args

    @abc.abstractmethod
    def multiply(self) -> int:
        pass

    @abc.abstractmethod
    def get_codec_options(self) -> dict:
        pass


class H264(Format):
    def __init__(self, video: str = "libx264", audio: str = 'aac', **codec_options):
        """
        @TODO: add documentation
        """
        videos = ['libx264', 'h264', 'h264_amf', 'h264_nvenc']
        audios = ['copy', 'aac', 'libvo_aacenc', 'libfaac', 'libmp3lame', 'libfdk_aac']

        super(H264, self).__init__(_verify_codecs(video, videos), _verify_codecs(audio, audios), **codec_options)

    def multiply(self) -> int:
        return MULTIPLY_BY_TWO

    def get_codec_options(self) -> dict:
        """
        set the default value of h264 codec options and update the value with the specified value by user
        see https://ffmpeg.org/ffmpeg-codecs.html#Options-28 for more information about options
        :return: dict
        """
        h264_codec_options = {
            'bf':           1,
            'keyint_min':   25,
            'g':            250,
            'sc_threshold': 40
        }

        h264_codec_options.update(self.codec_options)

        return h264_codec_options


class HEVC(Format):
    """
    @TODO: add documentation
    """
    def __init__(self, video: str = "libx265", audio: str = 'aac', **codec_options):
        videos = ['libx265', 'h265']
        audios = ['copy', 'aac', 'libvo_aacenc', 'libfaac', 'libmp3lame', 'libfdk_aac']

        super(HEVC, self).__init__(_verify_codecs(video, videos), _verify_codecs(audio, audios), **codec_options)

    def multiply(self) -> int:
        return MULTIPLY_BY_TWO

    def get_codec_options(self) -> dict:
        """
        set the default value of hevc(h265) codec options and update the value with the specified value by user
        see https://ffmpeg.org/ffmpeg-codecs.html#Options-29 for more information about options
        :return: dict
        """
        h265_codec_options = {
            'keyint_min':   25,
            'g':            250,
            'sc_threshold': 40
        }

        h265_codec_options.update(self.codec_options)

        return h265_codec_options


class VP9(Format):
    """
    @TODO: add documentation
    """
    def __init__(self, video: str = "libvpx-vp9", audio: str = 'aac', **codec_options):
        videos = ['libvpx', 'libvpx-vp9']
        audios = ['copy', 'aac', 'libvo_aacenc', 'libfaac', 'libmp3lame', 'libfdk_aac']

        super(VP9, self).__init__(_verify_codecs(video, videos), _verify_codecs(audio, audios), **codec_options)

    def multiply(self) -> int:
        return MULTIPLY_BY_TWO

    def get_codec_options(self) -> dict:
        """
        set the default value of vp9 codec options and update the value with the specified value by user
        see https://ffmpeg.org/ffmpeg-codecs.html#Options-26 for more information about options
        :return: dict
        """
        vp9_codec_options = {}

        vp9_codec_options.update(self.codec_options)

        return vp9_codec_options


class Formats:
    @staticmethod
    def h264(video: str = "libx264", audio: str = 'aac', **codec_options) -> Format:
        """
        @TODO: add documentation
        """
        return H264(video, audio, **codec_options)

    @staticmethod
    def hevc(video: str = "libx265", audio: str = 'aac', **codec_options) -> Format:
        """
        @TODO: add documentation
        """
        return HEVC(video, audio, **codec_options)

    @staticmethod
    def vp9(video: str = "libvpx-vp9", audio: str = 'aac', **codec_options) -> Format:
        """
        @TODO: add documentation
        """
        return VP9(video, audio, **codec_options)


__all__ = [
    'Format',
    'Formats'
]