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Diffstat (limited to 'youtube_dl/PostProcessor.py')
| -rw-r--r-- | youtube_dl/PostProcessor.py | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/youtube_dl/PostProcessor.py b/youtube_dl/PostProcessor.py new file mode 100644 index 000000000..52e686a7f --- /dev/null +++ b/youtube_dl/PostProcessor.py @@ -0,0 +1,185 @@ +#!/usr/bin/env python +# -*- coding: utf-8 -*- + +import os +import subprocess +import sys +import time + +from utils import * + + +class PostProcessor(object): + """Post Processor class. + + PostProcessor objects can be added to downloaders with their + add_post_processor() method. When the downloader has finished a + successful download, it will take its internal chain of PostProcessors + and start calling the run() method on each one of them, first with + an initial argument and then with the returned value of the previous + PostProcessor. + + The chain will be stopped if one of them ever returns None or the end + of the chain is reached. + + PostProcessor objects follow a "mutual registration" process similar + to InfoExtractor objects. + """ + + _downloader = None + + def __init__(self, downloader=None): + self._downloader = downloader + + def set_downloader(self, downloader): + """Sets the downloader for this PP.""" + self._downloader = downloader + + def run(self, information): + """Run the PostProcessor. + + The "information" argument is a dictionary like the ones + composed by InfoExtractors. The only difference is that this + one has an extra field called "filepath" that points to the + downloaded file. + + When this method returns None, the postprocessing chain is + stopped. However, this method may return an information + dictionary that will be passed to the next postprocessing + object in the chain. It can be the one it received after + changing some fields. + + In addition, this method may raise a PostProcessingError + exception that will be taken into account by the downloader + it was called from. + """ + return information # by default, do nothing + +class AudioConversionError(BaseException): + def __init__(self, message): + self.message = message + +class FFmpegExtractAudioPP(PostProcessor): + + def __init__(self, downloader=None, preferredcodec=None, preferredquality=None, keepvideo=False): + PostProcessor.__init__(self, downloader) + if preferredcodec is None: + preferredcodec = 'best' + self._preferredcodec = preferredcodec + self._preferredquality = preferredquality + self._keepvideo = keepvideo + + @staticmethod + def get_audio_codec(path): + try: + cmd = ['ffprobe', '-show_streams', '--', encodeFilename(path)] + handle = subprocess.Popen(cmd, stderr=file(os.path.devnull, 'w'), stdout=subprocess.PIPE) + output = handle.communicate()[0] + if handle.wait() != 0: + return None + except (IOError, OSError): + return None + audio_codec = None + for line in output.split('\n'): + if line.startswith('codec_name='): + audio_codec = line.split('=')[1].strip() + elif line.strip() == 'codec_type=audio' and audio_codec is not None: + return audio_codec + return None + + @staticmethod + def run_ffmpeg(path, out_path, codec, more_opts): + if codec is None: + acodec_opts = [] + else: + acodec_opts = ['-acodec', codec] + cmd = ['ffmpeg', '-y', '-i', encodeFilename(path), '-vn'] + acodec_opts + more_opts + ['--', encodeFilename(out_path)] + try: + p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE) + stdout,stderr = p.communicate() + except (IOError, OSError): + e = sys.exc_info()[1] + if isinstance(e, OSError) and e.errno == 2: + raise AudioConversionError('ffmpeg not found. Please install ffmpeg.') + else: + raise e + if p.returncode != 0: + msg = stderr.strip().split('\n')[-1] + raise AudioConversionError(msg) + + def run(self, information): + path = information['filepath'] + + filecodec = self.get_audio_codec(path) + if filecodec is None: + self._downloader.to_stderr(u'WARNING: unable to obtain file audio codec with ffprobe') + return None + + more_opts = [] + if self._preferredcodec == 'best' or self._preferredcodec == filecodec or (self._preferredcodec == 'm4a' and filecodec == 'aac'): + if self._preferredcodec == 'm4a' and filecodec == 'aac': + # Lossless, but in another container + acodec = 'copy' + extension = self._preferredcodec + more_opts = ['-absf', 'aac_adtstoasc'] + elif filecodec in ['aac', 'mp3', 'vorbis']: + # Lossless if possible + acodec = 'copy' + extension = filecodec + if filecodec == 'aac': + more_opts = ['-f', 'adts'] + if filecodec == 'vorbis': + extension = 'ogg' + else: + # MP3 otherwise. + acodec = 'libmp3lame' + extension = 'mp3' + more_opts = [] + if self._preferredquality is not None: + more_opts += ['-ab', self._preferredquality] + else: + # We convert the audio (lossy) + acodec = {'mp3': 'libmp3lame', 'aac': 'aac', 'm4a': 'aac', 'vorbis': 'libvorbis', 'wav': None}[self._preferredcodec] + extension = self._preferredcodec + more_opts = [] + if self._preferredquality is not None: + more_opts += ['-ab', self._preferredquality] + if self._preferredcodec == 'aac': + more_opts += ['-f', 'adts'] + if self._preferredcodec == 'm4a': + more_opts += ['-absf', 'aac_adtstoasc'] + if self._preferredcodec == 'vorbis': + extension = 'ogg' + if self._preferredcodec == 'wav': + extension = 'wav' + more_opts += ['-f', 'wav'] + + prefix, sep, ext = path.rpartition(u'.') # not os.path.splitext, since the latter does not work on unicode in all setups + new_path = prefix + sep + extension + self._downloader.to_screen(u'[ffmpeg] Destination: ' + new_path) + try: + self.run_ffmpeg(path, new_path, acodec, more_opts) + except: + etype,e,tb = sys.exc_info() + if isinstance(e, AudioConversionError): + self._downloader.to_stderr(u'ERROR: audio conversion failed: ' + e.message) + else: + self._downloader.to_stderr(u'ERROR: error running ffmpeg') + return None + + # Try to update the date time for extracted audio file. + if information.get('filetime') is not None: + try: + os.utime(encodeFilename(new_path), (time.time(), information['filetime'])) + except: + self._downloader.to_stderr(u'WARNING: Cannot update utime of audio file') + + if not self._keepvideo: + try: + os.remove(encodeFilename(path)) + except (IOError, OSError): + self._downloader.to_stderr(u'WARNING: Unable to remove downloaded video file') + return None + + information['filepath'] = new_path + return information |