"""
import cis_exceptions
+import re
class BaseTranscoder:
"""
- Abstractization of the API class for the transcoder program.
+ Abstraction of the API class for the transcoder program.
"""
prog_bin = None
input_file = None
+ output_file = None
+ dest_path = ''
+ name = None
# Recommended formats.
containers = {
"webm": None,
"mpegts": None
}
+ # File extensions by container. First value is for audio files and the
+ # second one is for (audio-)video files.
+ extensions = {
+ "avi": ["avi", "avi"],
+ "flv": ["flv", "flv"],
+ "mp4": ["mp4", "mp4"],
+ "ogg": ["oga", "ogv"],
+ "webm": ["webm", "webm"],
+ "mpegts": ["mts", "mts"]
+ }
a_codecs = {
"mp3": None,
"vorbis": None
"vp8": None
}
- def __init__(self, input_file, prog_bin=None):
+ def __init__(self, input_file, name=None, prog_bin=None):
self.input_file = input_file
- self.prog_bin = prog_bin
+ if prog_bin is not None:
+ self.prog_bin = prog_bin
+
+ if name is None:
+ if input_file.find('/') is not -1:
+ name = input_file[(input_file.rindex('/')+1):]
+ else:
+ name = input_file
+ if name.find('.') is not -1:
+ name = name[:name.rindex('.')]
+
+ self.name = name
- def transcode(self, container, a_codec, v_codec,
+ def transcode(self, container, a_codec=None, v_codec=None,
a_bitrate=None, a_samplingrate=None, a_channels=None,
- v_bitrate=None, v_fraterate=None, v_resolution=None, v_dar=None):
+ v_bitrate=None, v_framerate=None, v_resolution=None, v_dar=None):
"""
Transcodes the input file to an audio-video file.
container: possible values are listed in containers member as keys
a_codec: possible values are listed in a_codecs member as keys
v_codec: possible values are listed in v_codecs member as keys
+ a_bitrate: (numeric) audio bit rate
+ a_samplingrate: (numeric) audio sampling rate in Hz
+ a_channels: (numeric) number of audio channels
+ v_bitrate: (numeric) video bit rate
+ v_framerate: (numeric) number of frames per second for a video
+ v_resolution: (string) video image size as <width>x<height>
+ v_dar: video display aspect ratio as <den>x<num> or float
"""
- pass
+ # Check parameters.
+ if a_codec is None and v_codec is None:
+ raise ValueError('No audio or video codec specified.')
- def transcode_audio(self, container, a_codec,
- a_bitrate=None, a_samplingrate=None, a_channels=None):
- pass
+ if a_codec is not None and type(a_codec) is not str:
+ raise TypeError('Audio codec must be string.')
+
+ if v_codec is not None and type(v_codec) is not str:
+ raise TypeError('Video codec must be string.')
+
+ if a_samplingrate is not None and type(a_samplingrate) is not int:
+ raise TypeError('Audio sampling rate must be an integer.')
+
+ if a_channels is not None and type(a_channels) is not int:
+ raise TypeError('Audio channels parameter must be an integer.')
- def transcode_video(self, container, v_codec,
- v_bitrate=None, v_fraterate=None, v_resolution=None, v_dar=None):
+ if v_framerate is not None and type(v_framerate) is not int:
+ raise TypeError('Video frate rate must be an integer.')
+
+ if v_resolution is not None \
+ and re.match('[\d]+x[\d]+', v_resolution) is None:
+ raise ValueError('Video resolution must be a string like <width>x<height>.')
+
+ if v_dar is not None and (type(v_dar) is not float \
+ and re.match('[\d]+:[\d]+', v_dar) is None):
+ raise ValueError('Video display aspect ratio must be a float or a string like <den>:<num>.')
+
+ self.output_file = self.dest_path + self.name
+ if v_resolution is not None:
+ self.output_file += '_'
+ self.output_file += v_resolution[(v_resolution.rindex('x')+1):]
+ self.output_file += 'p'
+ ext = self.tr_extension(container, (v_codec is not None))
+ if ext is not None:
+ self.output_file += '.' + ext
+
+ self._transcode(self.tr_container(container),
+ self.tr_a_codec(a_codec), self.tr_v_codec(v_codec),
+ a_bitrate, a_samplingrate, a_channels,
+ v_bitrate, v_framerate, v_resolution, v_dar)
+
+ def _transcode(self, container, a_codec=None, v_codec=None,
+ a_bitrate=None, a_samplingrate=None, a_channels=None,
+ v_bitrate=None, v_framerate=None, v_resolution=None, v_dar=None):
+ """
+ Called by transcode; must be overridden by a child class which
+ effectively transcodes the input file.
+ """
pass
def tr_container(self, name):
""" Translates container API name into external program identifier."""
- if not self.containers.has_key(name) or self.containers[name] == None:
+ if not self.containers.has_key(name) or self.containers[name] is None:
raise cis_exceptions.NotImplementedException("Container " + name)
return self.containers[name]
+
+ def tr_extension(self, name, video=True):
+ """ Translates container API name into file extension."""
+
+ if video is True:
+ i = 1
+ else:
+ i = 0
+
+ if not self.extensions.has_key(name) or self.extensions[name] is None:
+ return None
+
+ return self.extensions[name][i]
+
+ def tr_a_codec(self, name):
+ """ Translates audio codec API name into external program identifier."""
+
+ if not self.a_codecs.has_key(name) or self.a_codecs[name] is None:
+ raise cis_exceptions.NotImplementedException("Audio Codec " + name)
+
+ return self.a_codecs[name]
+
+ def tr_v_codec(self, name):
+ """ Translates video codec API name into external program identifier."""
+
+ if not self.v_codecs.has_key(name) or self.v_codecs[name] is None:
+ raise cis_exceptions.NotImplementedException("Video Codec " + name)
+
+ return self.v_codecs[name]
projects / living-lab-site.git / blobdiff