Module `stempeg.cmds`

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import re
import subprocess as sp
import logging

FFMPEG_PATH = None
FFPROBE_PATH = None
MP4BOX_PATH = None


def find_cmd(cmd):
    try:
        from shutil import which
        return which(cmd)
    except ImportError:
        import os
        for path in os.environ["PATH"].split(os.pathsep):
            if os.access(os.path.join(path, cmd), os.X_OK):
                return path

    return None


def ffmpeg_and_ffprobe_exists():
    global FFMPEG_PATH, FFPROBE_PATH
    if FFMPEG_PATH is None:
        FFMPEG_PATH = find_cmd("ffmpeg")

    if FFPROBE_PATH is None:
        FFPROBE_PATH = find_cmd("ffprobe")

    return FFMPEG_PATH is not None and FFPROBE_PATH is not None


def mp4box_exists():
    global MP4BOX_PATH
    if MP4BOX_PATH is None:
        MP4BOX_PATH = find_cmd("MP4Box")

    return MP4BOX_PATH is not None


if not ffmpeg_and_ffprobe_exists():
    raise RuntimeError(
        'ffmpeg or ffprobe could not be found! '
        'Please install them before using stempeg. '
        'See: https://github.com/faroit/stempeg'
    )


def check_available_aac_encoders():
    """Returns the available AAC encoders

    Returns:
        list(str): List of available encoder codecs from ffmpeg

    """
    cmd = [
        FFMPEG_PATH,
        '-v', 'error',
        '-codecs'
    ]

    output = sp.check_output(cmd)
    aac_codecs = [
        x for x in
        output.splitlines() if "AAC (Advanced Audio Coding)" in str(x)
    ][0]
    hay = aac_codecs.decode('ascii')
    match = re.findall(r'\(encoders: ([^\)]*) \)', hay)
    if match:
        return match[0].split(" ")
    else:
        return None


def get_aac_codec():
    """Checks codec and warns if `libfdk_aac` codec
     is not available.

    Returns:
        str: ffmpeg aac codec name
    """
    avail = check_available_aac_encoders()
    if avail is not None:
        if 'libfdk_aac' in avail:
            codec = 'libfdk_aac'
        else:
            logging.warning(
                "For the better audio quality, install `libfdk_aac` codec."
            )
            codec = 'aac'
    else:
        codec = 'aac'

    return codec

Functions

def check_available_aac_encoders()

Returns the available AAC encoders

Returns

list(str): List of available encoder codecs from ffmpeg

Expand source code Browse git

def check_available_aac_encoders():
    """Returns the available AAC encoders

    Returns:
        list(str): List of available encoder codecs from ffmpeg

    """
    cmd = [
        FFMPEG_PATH,
        '-v', 'error',
        '-codecs'
    ]

    output = sp.check_output(cmd)
    aac_codecs = [
        x for x in
        output.splitlines() if "AAC (Advanced Audio Coding)" in str(x)
    ][0]
    hay = aac_codecs.decode('ascii')
    match = re.findall(r'\(encoders: ([^\)]*) \)', hay)
    if match:
        return match[0].split(" ")
    else:
        return None

def ffmpeg_and_ffprobe_exists()

Expand source code Browse git

def ffmpeg_and_ffprobe_exists():
    global FFMPEG_PATH, FFPROBE_PATH
    if FFMPEG_PATH is None:
        FFMPEG_PATH = find_cmd("ffmpeg")

    if FFPROBE_PATH is None:
        FFPROBE_PATH = find_cmd("ffprobe")

    return FFMPEG_PATH is not None and FFPROBE_PATH is not None

def find_cmd(cmd)

Expand source code Browse git

def find_cmd(cmd):
    try:
        from shutil import which
        return which(cmd)
    except ImportError:
        import os
        for path in os.environ["PATH"].split(os.pathsep):
            if os.access(os.path.join(path, cmd), os.X_OK):
                return path

    return None

def get_aac_codec()

Checks codec and warns if libfdk_aac codec is not available.

Returns

str: ffmpeg aac codec name

Expand source code Browse git

def get_aac_codec():
    """Checks codec and warns if `libfdk_aac` codec
     is not available.

    Returns:
        str: ffmpeg aac codec name
    """
    avail = check_available_aac_encoders()
    if avail is not None:
        if 'libfdk_aac' in avail:
            codec = 'libfdk_aac'
        else:
            logging.warning(
                "For the better audio quality, install `libfdk_aac` codec."
            )
            codec = 'aac'
    else:
        codec = 'aac'

    return codec

def mp4box_exists()

Expand source code Browse git

def mp4box_exists():
    global MP4BOX_PATH
    if MP4BOX_PATH is None:
        MP4BOX_PATH = find_cmd("MP4Box")

    return MP4BOX_PATH is not None