3 ### Convert a directory tree of audio files
5 ### (c) 2010 Mark Wooding
8 ###----- Licensing notice ---------------------------------------------------
10 ### This file is part of the `autoys' audio tools collection.
12 ### `autoys' is free software; you can redistribute it and/or modify
13 ### it under the terms of the GNU General Public License as published by
14 ### the Free Software Foundation; either version 2 of the License, or
15 ### (at your option) any later version.
17 ### `autoys' is distributed in the hope that it will be useful,
18 ### but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ### GNU General Public License for more details.
22 ### You should have received a copy of the GNU General Public License
23 ### along with `autoys'; if not, write to the Free Software Foundation,
24 ### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26 ###--------------------------------------------------------------------------
27 ### External dependencies.
30 from __future__ import with_statement
32 ## Standard Python libraries.
37 import unicodedata as UD
42 import threading as TH
45 from contextlib import contextmanager
47 ## eyeD3 tag fettling.
50 ## Gstreamer. It picks up command-line arguments -- most notably `--help' --
51 ## and processes them itself. Of course, its help is completely wrong. This
52 ## kludge is due to Jonas Wagner.
53 _argv, SYS.argv = SYS.argv, []
60 from PIL import Image as I
65 ###--------------------------------------------------------------------------
66 ### Special initialization.
73 ###--------------------------------------------------------------------------
74 ### Eyecandy progress reports.
78 Return the width of S, in characters.
80 Specifically, this is the number of backspace characters required to
81 overprint the string S. If the current encoding for `stdout' appears to be
82 Unicode then do a complicated Unicode thing; otherwise assume that
83 characters take up one cell each.
85 None of this handles tab characters in any kind of useful way. Sorry.
88 ## If there's no encoding for stdout then we're doing something stupid.
89 if SYS.stdout.encoding is None: return len(s)
91 ## Turn the string into Unicode so we can hack on it properly. Maybe that
92 ## won't work out, in which case fall back to being stupid.
93 try: u = s.decode(SYS.stdout.encoding)
94 except UnicodeError: return len(s)
96 ## Our main problem is combining characters, but we should also try to
97 ## handle wide (mostly Asian) characters, and zero-width ones. This hack
98 ## is taken mostly from http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
102 if UD.category(ch) in ['Cf', 'Me', 'Mn'] or \
103 0x1160 <= cd <= 0x11ff: pass
104 elif UD.east_asian_width(ch) in ['F', 'W']: w += 2
110 class StatusLine (object):
112 Maintains a status line containing ephemeral progress information.
114 The status line isn't especially important, but it keeps interactive users
117 There should be only one status line object in your program; otherwise
118 they'll interfere with each other and get confused.
120 The update algorithm (in `set') is fairly careful to do the right thing
121 with long status `lines', and to work properly in an Emacs `shell' buffer.
125 "Initialize the status line."
128 me.eyecandyp = OS.isatty(SYS.stdout.fileno())
132 Set the status line contents to LINE, replacing what was there before.
134 This only produces actual output if stdout is interactive.
141 ## If the old line was longer, we need to clobber its tail, so work out
142 ## what that involves.
144 b = charwidth(me._last[n:])
149 ## Now figure out the length of the common prefix between what we had
150 ## before and what we have now. This reduces the amount of I/O done,
151 ## which keeps network traffic down on SSH links, and keeps down the
152 ## amount of work slow terminal emulators like Emacs have to do.
154 m = min(n, me._lastlen)
155 while i < m and line[i] == me._last[i]:
158 ## Actually do the output, all in one syscall.
159 b = charwidth(me._last[i:])
160 SYS.stdout.write(pre + '\b'*b + line[i:])
163 ## Update our idea of what's gone on.
168 "Clear the status line. Just like set('')."
171 def commit(me, line = None):
173 Commit the current status line, and maybe the string LINE.
175 If the current status line is nonempty, then commit it to the transcript.
176 If LINE is not None, then commit that to the transcript too.
178 After all of this, we clear the status line to get back to a clean state.
182 SYS.stdout.write('\n')
184 SYS.stdout.write(me._last + '\n')
186 SYS.stdout.write(line + '\n')
190 STATUS = StatusLine()
192 def filestatus(file, status):
193 return '%s%s: %s' % (' '*8, OS.path.basename(file), status)
195 class ProgressEyecandy (object):
197 Provide amusement while something big and complicated is happening.
199 This is an abstract class. Subclasses must provide a method `progress'
200 returning a pair (CURRENT, MAX) indicating the current progress through the
204 def __init__(me, what, silentp = False):
206 Initialize a progress meter.
208 WHAT is a prefix string to be written before the progress eyecandy
212 me._silentp = silentp
216 def _fmt_time(me, t):
217 "Format T as a time, in (maybe hours) minutes and seconds."
218 s, t = t % 60, int(t/60)
219 m, h = t % 60, int(t/60)
221 return '%d:%02d:%02d' % (h, m, s)
223 return '%02d:%02d' % (m, s)
226 "Show the current level of progress."
228 ## If we're not showing pointless frippery, don't bother at all.
229 if not STATUS.eyecandyp:
232 ## Update the spinner index.
233 me._spinner = (me._spinner + 1)%4
235 ## Fetch the current progress information. Note that we always fetch
236 ## both the current and maximum levels, because both might change if an
237 ## operation revises its idea of how much work needs doing.
238 cur, max = me.progress()
240 ## If we couldn't get progress information, display something vaguely
242 if cur is None or max is None:
243 STATUS.set('%s %c [unknown progress]' %
244 (me._what, r'/-\|'[me._spinner]))
247 ## Work out -- well, guess -- the time remaining.
250 eta = me._fmt_time((t - me._start)*(max - cur)/cur)
254 ## Set the status bar.
256 STATUS.set('%s %c [%s%s] %3d%% (%s)' % \
258 r'/-\|'[me._spinner],
263 def done(me, win = True):
264 "Show a completion notice, or a failure if WIN is false."
266 STATUS.set('%s FAILED!' % me._what)
267 elif not me._silentp:
268 STATUS.set('%s done (%s)' %
270 me._fmt_time(T.time() - me._start)))
275 ###--------------------------------------------------------------------------
276 ### Timeout handling.
278 KILLSWITCH = TH.Event()
284 moan('dying messily due to timeout')
287 ###--------------------------------------------------------------------------
288 ### Parsing utilities.
290 ## Allow hyphens in identifiers.
291 IDCHARS = P.alphanums + '-_'
292 P.Keyword.setDefaultKeywordChars(IDCHARS)
294 ## Some common kinds of tokens.
295 Name = P.Word(IDCHARS)
296 Num = P.Word(P.nums).setParseAction(lambda toks: map(int, toks))
297 String = P.QuotedString('"', '\\')
299 ## Handy abbreviations for constructed parser elements.
300 def K(k): return P.Keyword(k).suppress()
301 def D(d): return P.Literal(d).suppress()
302 def R(p): return P.ZeroOrMore(p).setParseAction(lambda s, l, t: [t])
305 ###--------------------------------------------------------------------------
306 ### Format identification and conversion.
308 class IdentificationFailure (Exception):
311 class FileCategory (object):
313 A FileCategory represents a class of files.
315 For example, it's sensible to consider audio, or image files as a
316 category. A file category knows how to recognize member files from
320 def __init__(me, name, mime_pats, ident):
322 Construct a new category.
324 The PATS are a list of `fnmatch' patterns to be compared with a MIME
325 type. The IDENT is a function which produces an identification object
326 given a file's name and first-guess MIME type. The object is passed to a
327 Format's `check' method to see whether a file needs re-encoding, and to
328 `convert' to assist with the conversion.
330 An identification object must have an attribute `mime' which is a set of
331 possible MIME types accumulated for the object.
334 me._mime_pats = mime_pats
336 CATEGORYMAP[name] = me
338 def identify(me, file, mime):
340 Attempt to identify FILE, given its apparent MIME type.
342 If identification succeeds, return an identification object which can be
343 used by associated file formats; otherwise return None.
345 for p in me._mime_pats:
346 if not FN.fnmatchcase(mime, p):
349 return me._ident(file, mime)
350 except IdentificationFailure:
354 class BaseFormat (object):
356 A BaseFormat object represents a particular encoding and parameters.
358 The object can verify (the `check' method) whether a particular file
359 matches its requirements, and if necessary (`encode') re-encode a file.
361 Subclasses should define the following methods.
364 Answer whether the file identified by ID is acceptable according to
365 the receiver's parameters.
367 convert(MASTER, ID, TARGET)
368 Convert the file MASTER, which has been identified as ID, according
369 to the receiver's parameters, writing the output to TARGET.
371 Subclasses should also provide these attributes.
374 A FileCategory object for the category of files that this format
377 EXT A file extension to be applied to encoded output files.
379 NAME A user-facing name for the format.
381 PROPS A parser element to parse a property definition. It should produce
382 a pair NAME, VALUE to be stored in a dictionary.
384 Subclasses for different kinds of file may introduce more subclass
389 """Post-encoding fixups."""
395 def defformat(name, cls):
396 "Define a format NAME using class CLS."
397 if not hasattr(cls, 'NAME'):
398 raise ValueError, 'abstract class'
399 if not hasattr(cls, 'CATEGORY'):
400 raise ValueError, 'no category'
401 FORMATMAP[name] = cls
403 class FormatParser (P.ParserElement):
405 Parse a format specifier:
407 format-spec ::= string [format-properties]
408 format-properties ::= `{' format-property (`,' format-property)* `}'
410 The syntax of a format-property is determined by the PROPS attribute on the
411 named format and its superclasses.
414 ## We cache the parser elements we generate to avoid enormous consing.
417 def parseImpl(me, s, loc, actp = True):
419 ## Firstly, determine the format name.
420 loc, r = Name._parse(s, loc, actp)
423 ## Look up the format class.
424 try: fcls = FORMATMAP[fmt]
426 raise P.ParseException(s, loc, "Unknown format `%s'" % fmt)
428 ## Fetch the property-list parser from the cache, if possible; else
437 except AttributeError: continue
438 if p in seen: continue
439 if prop is None: prop = p
443 pp = me.CACHE[fmt] = None
445 props = P.delimitedList(prop)
446 props.setParseAction(lambda s, l, t: dict(t.asList()))
447 pp = me.CACHE[fmt] = O(D('{') - props - D('}'))
449 ## Parse the properties.
453 loc, r = pp._parse(s, loc, actp)
457 ## Construct the format object and return it.
458 return loc, fcls(**pd)
460 Format = FormatParser()
462 def prop(kw, pval, tag = None):
463 if tag is None: tag = kw
466 p.setParseAction(lambda s, l, t: (tag, True))
468 p = K(kw) + D('=') + pval
469 p.setParseAction(lambda s, l, t: (tag, t[0]))
472 ###--------------------------------------------------------------------------
473 ### Policies and actions.
475 class Action (object):
477 An Action object represents a conversion action to be performed.
479 This class isn't intended to be instantiated directly. It exists to define
480 some protocol common to all Action objects.
482 Action objects have the following attributes.
484 master The name of the master (source) file.
486 target The name of the target (destination) file.
488 PRIORITY The priority of the action, for deciding which of two actions
489 to perform. Higher priorities are more likely to win.
491 Converting an Action to a string describes the action in a simple
492 user-readable manner. The `perform' method actually carries the action
498 def __init__(me, master):
499 "Stash the MASTER file name for later."
503 "Choose either ME or HIM and return one."
504 if him is None or me.PRIORITY > him.PRIORITY:
509 class CopyAction (Action):
511 An Action object for simply copying a file.
513 Actually we try to hardlink it first, falling back to a copy later. This
514 is both faster and more efficient with regard to disk space.
517 ## Copying is good. Linking is really good, but we can't tell the
518 ## difference at this stage.
521 def __init__(me, master, targetdir):
522 "Initialize a CopyAction, from MASTER to the TARGETDIR directory."
523 Action.__init__(me, master)
524 me.target = OS.path.join(targetdir, OS.path.basename(master))
530 "Actually perform a CopyAction."
532 STATUS.set(filestatus(me.master, 'link'))
533 OS.link(me.master, me.target)
535 if err.errno != E.EXDEV:
537 STATUS.set(filestatus(me.master, 'copy'))
538 new = me.target + '.new'
539 SH.copyfile(me.master, new)
540 OS.rename(new, me.target)
543 class ConvertAction (Action):
545 An Action object for converting a file to a given format.
547 Additional attributes:
549 id The identification object for the master file.
551 format The format to which we're meant to conver the master.
554 def __init__(me, master, targetdir, id, format):
555 "Initialize a ConvertAction."
556 Action.__init__(me, master)
557 stem, ext = OS.path.splitext(OS.path.basename(master))
558 me.target = OS.path.join(targetdir, stem + '.' + format.EXT)
563 return 'convert to %s' % me.format.NAME
566 "Acually perform a ConvertAction."
567 STATUS.set(filestatus(me.master, me))
568 me.format.convert(me.master, me.id, me.target)
572 class FormatPolicy (object):
574 A FormatPolicy object represents a set of rules for how to convert files.
576 Given a master file, the FormatPolicy will identify it and return a list of
577 actions to be performed. The methods required of a FormatPolicy are:
580 Store CAT as the policy's category. Check that this is consistent
581 with the policy as stored.
583 actions(MASTER, TARGETDIR, ID, COHORT)
584 Given a MASTER file, identified as ID, a target directory
585 TARGETDIR, and a list COHORT of (FILE, ID) pairs for other files
586 of the same category in the same directory, return a list of
587 actions to be performed to get the target directory into the right
588 form. The list might be empty if the policy object /rejects/ the
592 class AndPolicy (FormatPolicy):
594 A FormatPolicy which does the union of a bunch of other policies.
596 Each subsidiary policy is invoked in turn. The highest-priority action for
597 each target file is returned.
600 def __init__(me, policies):
601 me._policies = policies
603 def setcategory(me, cat):
605 for p in me._policies:
608 def actions(me, master, targetdir, id, cohort):
610 for p in me._policies:
611 for a in p.actions(master, targetdir, id, cohort):
613 tmap[a.target] = a.choose(tmap.get(a.target))
618 And = K('and') - D('{') - R(Policy) - D('}')
619 And.setParseAction(lambda s, l, t: AndPolicy(t[0]))
621 class OrPolicy (FormatPolicy):
623 A FormatPolicy which tries other policies and uses the first that accepts.
625 Each subsidiary policy is invoked in turn. If any accepts, the actions it
626 proposes are turned and no further policies are invoked. If none accepts
627 then the file is rejected.
630 def __init__(me, policies):
631 me._policies = policies
633 def setcategory(me, cat):
635 for p in me._policies:
638 def actions(me, master, targetdir, id, cohort):
639 for p in me._policies:
640 aa = p.actions(master, targetdir, id, cohort)
646 Or = K('or') - D('{') - R(Policy) - D('}')
647 Or.setParseAction(lambda s, l, t: OrPolicy(t[0]))
649 class AcceptPolicy (FormatPolicy):
651 A FormatPolicy which copies files in a particular format.
653 If all of the files in a cohort are recognized as being in a particular
654 format (including this one), then accept it with a CopyAction; otherwise
658 def __init__(me, format):
661 def setcategory(me, cat):
662 if me._format.CATEGORY is not cat:
664 "Accept format `%s' has category `%s', not `%s'" % \
665 (me._format.__class__.__name__,
666 me._format.CATEGORY.name, cat.name)
669 def actions(me, master, targetdir, id, cohort):
670 if me._format.check(id) and \
671 all(me._format.check(cid) for f, cid in cohort):
672 return [CopyAction(master, targetdir)]
676 Accept = K('accept') - Format
677 Accept.setParseAction(lambda s, l, t: AcceptPolicy(t[0]))
679 class ConvertPolicy (FormatPolicy):
681 A FormatPolicy which copies files in a particular format or converts if
684 def __init__(me, format):
687 def setcategory(me, cat):
688 if me._format.CATEGORY is not cat:
690 "Accept format `%s' has category `%s', not `%s'" % \
691 (me._format.__class__.__name__,
692 me._format.CATEGORY.name, cat.name)
695 def actions(me, master, targetdir, id, cohort):
696 if me._format.check(id):
697 return [CopyAction(master, targetdir)]
699 return [ConvertAction(master, targetdir, id, me._format)]
701 Convert = K('convert') - Format
702 Convert.setParseAction(lambda s, l, t: ConvertPolicy(t[0]))
704 Policy << (And | Or | Accept | Convert)
706 ###--------------------------------------------------------------------------
707 ### Audio handling, based on GStreamer.
709 def make_element(factory, name = None, **props):
710 "Return a new element from the FACTORY with the given NAME and PROPS."
711 elt = GS.element_factory_make(factory, name)
712 elt.set_properties(**props)
715 class GStreamerProgressEyecandy (ProgressEyecandy):
717 Provide amusement while GStreamer is busy doing something.
719 The GStreamerProgressEyecandy object is a context manager. Wrap it round
720 your GStreamer loop to provide progress information for an operation.
723 def __init__(me, what, elt, **kw):
725 Initialize a progress meter.
727 WHAT is a prefix string to be written before the progress eyecandy
728 itself. ELT is a GStreamer element to interrogate to find the progress
732 ProgressEyecandy.__init__(me, what, **kw)
735 "Called by GLib main event loop to update the eyecandy."
741 Update the progress meter.
743 This is called periodically by the GLib main event-processing loop.
749 "Return the current progress as a pair (CURRENT, MAX)."
751 ## Fetch the current progress information. We get the duration each
752 ## time, because (particularly with VBR-encoded MP3 inputs) the estimated
753 ## duration can change as we progress. Hopefully it settles down fairly
756 t, hunoz = me._elt.query_position(GS.FORMAT_TIME)
757 end, hukairz = me._elt.query_duration(GS.FORMAT_TIME)
759 except GS.QueryError:
763 "Enter context: attach progress meter display."
765 ## If we're not showing pointless frippery, don't bother at all.
766 if not STATUS.eyecandyp:
769 ## Update regularly. The pipeline runs asynchronously.
770 me._id = G.timeout_add(200, me._update)
772 def __exit__(me, ty, val, tb):
773 "Leave context: remove display and report completion or failure."
775 ## If we're not showing pointless frippery, there's nothing to remove.
777 G.source_remove(me._id)
779 ## Report completion anyway.
785 class AudioIdentifier (object):
787 Analyses and identifies an audio file.
789 Important properties are:
791 cap A capabilities structure describing the audio file data. The most
792 interesting thing in here is probably its name, which is a MIME
793 type describing the data.
795 dcap A capabilities structure describing the decoded audio data. This
796 is of interest during conversion.
798 tags A dictionary containing metadata tags from the file. These are in
799 GStreamer's encoding-independent format.
801 bitrate An approximation to the stream's bitrate, in kilobits per second.
802 This might be slow to work out for some files so it's computed on
806 def __init__(me, file, mime):
807 "Initialize the object suitably for identifying FILE."
809 ## Make some initial GStreamer objects. We'll want the pipeline later if
810 ## we need to analyse a poorly tagged MP3 stream, so save it away.
811 me._pipe = GS.Pipeline()
813 bus = me._pipe.get_bus()
814 bus.add_signal_watch()
817 ## The basic recognition kit is based around `decodebin'. We must keep
818 ## it happy by giving it sinks for the streams it's found, which it
819 ## announces asynchronously.
820 source = make_element('filesrc', 'file', location = file)
821 decoder = make_element('decodebin', 'decode')
822 sink = make_element('fakesink')
823 def decoder_pad_arrived(elt, pad):
824 if pad.get_caps()[0].get_name().startswith('audio/'):
825 elt.link_pads(pad.get_name(), sink, 'sink')
826 dpaid = decoder.connect('pad-added', decoder_pad_arrived)
827 me._pipe.add(source, decoder, sink)
828 GS.element_link_many(source, decoder)
830 ## Arrange to collect tags from the pipeline's bus as they're reported.
831 ## If we reuse the pipeline later, we'll want different bus-message
832 ## handling, so make sure we can take the signal handler away.
835 def bus_message(bus, msg):
836 if msg.type == GS.MESSAGE_ERROR:
837 fail[:] = (ValueError, msg.structure['debug'], None)
839 elif msg.type == GS.MESSAGE_STATE_CHANGED:
840 if msg.structure['new-state'] == GS.STATE_PAUSED and \
843 elif msg.type == GS.MESSAGE_TAG:
844 tags.update(msg.structure)
845 bmid = bus.connect('message', bus_message)
847 ## We want to identify the kind of stream this is. (Hmm. The MIME type
848 ## recognizer has already done this work, but GStreamer is probably more
849 ## reliable.) The `decodebin' has a `typefind' element inside which will
850 ## announce the identified media type. All we need to do is find it and
851 ## attach a signal handler. (Note that the handler might be run in the
852 ## thread context of the pipeline element, but Python's GIL will keep
853 ## things from being too awful.)
856 for e in decoder.elements():
857 if e.get_factory().get_name() == 'typefind':
861 assert False, 'failed to find typefind element'
863 ## Crank up most of the heavy machinery. The message handler will stop
864 ## the loop when things seem to be sufficiently well underway.
865 me._pipe.set_state(GS.STATE_PAUSED)
868 decoder.disconnect(dpaid)
870 me._pipe.set_state(GS.STATE_NULL)
871 raise fail[0], fail[1], fail[2]
873 ## Store the collected tags.
876 ## Gather the capabilities. The `typefind' element knows the input data
877 ## type. The 'decodebin' knows the raw data type.
878 me.cap = tfelt.get_pad('src').get_negotiated_caps()[0]
879 me.mime = set([mime, me.cap.get_name()])
880 me.dcap = sink.get_pad('sink').get_negotiated_caps()[0]
882 ## If we found a plausible bitrate then stash it. Otherwise note that we
883 ## failed. If anybody asks then we'll work it out then.
884 if 'nominal-bitrate' in tags:
885 me._bitrate = tags['nominal-bitrate']/1000
886 elif 'bitrate' in tags and tags['bitrate'] >= 80000:
887 me._bitrate = tags['bitrate']/1000
891 ## The bitrate computation wants the file size. Ideally we'd want the
892 ## total size of the frames' contents, but that seems hard to dredge
893 ## out. If the framing overhead is small, this should be close enough
895 me._bytes = OS.stat(file).st_size
898 "Close the pipeline down so we don't leak file descriptors."
899 me._pipe.set_state(GS.STATE_NULL)
904 Return the approximate bit-rate of the input file.
906 This might take a while if we have to work it out the hard way.
909 ## If we already know the answer then just return it.
910 if me._bitrate is not None:
913 ## Make up a new main loop.
916 ## Watch for bus messages. We'll stop when we reach the end of the
917 ## stream: then we'll have a clear idea of how long the track was.
919 def bus_message(bus, msg):
920 if msg.type == GS.MESSAGE_ERROR:
921 fail[:] = (ValueError, msg.structure['debug'], None)
923 elif msg.type == GS.MESSAGE_EOS:
925 bus = me._pipe.get_bus()
926 bmid = bus.connect('message', bus_message)
928 ## Get everything moving, and keep the user amused while we work.
929 me._pipe.set_state(GS.STATE_PLAYING)
930 with GStreamerProgressEyecandy(filestatus(file, 'measure bitrate') %
936 me._pipe.set_state(GS.STATE_NULL)
937 raise fail[0], fail[1], fail[2]
939 ## Now we should be able to find out our position accurately and work out
940 ## a bitrate. Cache it in case anybody asks again.
941 t, hukairz = me._pipe.query_position(GS.FORMAT_TIME)
942 me._bitrate = int(8*me._bytes*1e6/t)
947 class AudioFormat (BaseFormat):
949 An AudioFormat is a kind of Format specialized for audio files.
951 Format checks are done on an AudioIdentifier object.
954 PROPS = prop('bitrate', Num)
956 ## libmagic reports `application/ogg' for Ogg Vorbis files. We've switched
957 ## to GIO now, which reports either `audio/ogg' or `audio/x-vorbis+ogg'
958 ## depending on how thorough it's trying to be. Still, it doesn't do any
959 ## harm here; the main risk is picking up Ogg Theora files by accident, and
960 ## we'll probably be able to extract the audio from them anyway.
961 CATEGORY = FileCategory('audio', ['audio/*', 'application/ogg'],
964 def __init__(me, bitrate = None):
965 "Construct an object, requiring an approximate bitrate."
970 Return whether the AudioIdentifier ID is suitable for our purposes.
972 Subclasses can either override this method or provide a property
973 `MIMETYPES', which is a list (other thing that implements `__contains__')
974 of GStreamer MIME types matching this format.
976 return id.mime & me.MIMETYPES and \
977 (me.bitrate is None or id.bitrate <= me.bitrate * sqrt(2))
981 Constructs a GStreamer element to encode audio input.
983 Subclasses can either override this method (or replace `encode'
984 entirely), or provide a method `encoder_chain' which returns a list of
985 elements to be linked together in sequence. The first element in the
986 chain must have a pad named `sink' and the last must have a pad named
989 elts = me.encoder_chain()
992 GS.element_link_many(*elts)
993 bin.add_pad(GS.GhostPad('sink', elts[0].get_pad('sink')))
994 bin.add_pad(GS.GhostPad('src', elts[-1].get_pad('src')))
997 def convert(me, master, id, target):
999 Encode audio from MASTER, already identified as ID, writing it to TARGET.
1001 See `encoder' for subclasses' responsibilities.
1004 ## Construct the necessary equipment.
1005 pipe = GS.Pipeline()
1006 bus = pipe.get_bus()
1007 bus.add_signal_watch()
1010 ## Make sure that there isn't anything in the way of our output. We're
1011 ## going to write to a scratch file so that we don't get confused by
1012 ## half-written rubbish left by a crashed program.
1013 new = target + '.new'
1016 except OSError, err:
1017 if err.errno != E.ENOENT:
1020 ## Piece together our pipeline. The annoying part is that the
1021 ## `decodebin' doesn't have any source pads yet, so our chain is in two
1023 source = make_element('filesrc', 'source', location = master)
1024 decoder = make_element('decodebin', 'decode')
1025 convert = make_element('audioconvert', 'convert')
1026 encoder = me.encoder()
1027 sink = make_element('filesink', 'sink', location = new)
1028 pipe.add(source, decoder, convert, encoder, sink)
1029 GS.element_link_many(source, decoder)
1030 GS.element_link_many(convert, encoder, sink)
1032 ## Some decoders (e.g., the AC3 decoder) include channel-position
1033 ## indicators in their output caps. The Vorbis encoder interferes with
1034 ## this, and you end up with a beautifully encoded mono signal from a
1035 ## stereo source. From a quick butchers at the `vorbisenc' source, I
1036 ## /think/ that this is only a problem with stereo signals: mono signals
1037 ## are mono already, and `vorbisenc' accepts channel positions if there
1038 ## are more than two channels.
1040 ## So we have this bodge. We already collected the decoded audio caps
1041 ## during identification. So if we see 2-channel audio with channel
1042 ## positions, we strip the positions off forcibly by adding a filter.
1043 if id.dcap.get_name().startswith('audio/x-raw-') and \
1044 id.dcap.has_field('channels') and \
1045 id.dcap['channels'] == 2 and \
1046 id.dcap.has_field('channel-positions'):
1049 c.remove_field('channel-positions')
1054 ## Hook onto the `decodebin' so we can link together the two halves of
1055 ## our encoding chain. For now, we'll hope that there's only one audio
1056 ## stream in there, and just throw everything else away.
1057 def decoder_pad_arrived(elt, pad):
1058 if pad.get_caps()[0].get_name().startswith('audio/'):
1060 elt.link_pads_filtered(pad.get_name(), convert, 'sink', dcap)
1062 elt.link_pads(pad.get_name(), convert, 'sink')
1063 decoder.connect('pad-added', decoder_pad_arrived)
1065 ## Watch the bus for completion messages.
1067 def bus_message(bus, msg):
1068 if msg.type == GS.MESSAGE_ERROR:
1069 fail[:] = (ValueError, msg.structure['debug'], None)
1071 elif msg.type == GS.MESSAGE_EOS:
1073 bmid = bus.connect('message', bus_message)
1075 ## Get everything ready and let it go.
1076 pipe.set_state(GS.STATE_PLAYING)
1077 with GStreamerProgressEyecandy(filestatus(master,
1078 'convert to %s' % me.NAME),
1081 pipe.set_state(GS.STATE_NULL)
1083 raise fail[0], fail[1], fail[2]
1085 ## Fix up the output file if we have to.
1089 OS.rename(new, target)
1091 class OggVorbisFormat (AudioFormat):
1092 "AudioFormat object for Ogg Vorbis."
1094 ## From https://en.wikipedia.org/wiki/Vorbis
1095 QMAP = [(-1, 45), ( 0, 64), ( 1, 80), ( 2, 96),
1096 ( 3, 112), ( 4, 128), ( 5, 160), ( 6, 192),
1097 ( 7, 224), ( 8, 256), ( 9, 320), (10, 500)]
1100 MIMETYPES = set(['application/ogg', 'audio/x-vorbis', 'audio/ogg',
1101 'audio/x-vorbis+ogg'])
1104 def encoder_chain(me):
1106 if me.bitrate is not None:
1107 for q, br in me.QMAP:
1108 if br >= me.bitrate:
1111 raise ValueError, 'no suitable quality setting found'
1112 encprops['quality'] = q/10.0
1113 return [make_element('vorbisenc', **encprops),
1114 make_element('oggmux')]
1116 defformat('ogg-vorbis', OggVorbisFormat)
1118 class MP3Format (AudioFormat):
1119 "AudioFormat object for MP3."
1122 MIMETYPES = set(['audio/mpeg'])
1125 def encoder_chain(me):
1127 if me.bitrate is not None: encprops['vbr_mean_bitrate'] = me.bitrate
1128 return [make_element('lame', vbr = 4, **encprops),
1129 make_element('xingmux'),
1130 make_element('id3v2mux')]
1132 def fixup(me, path):
1136 GStreamer produces ID3v2 tags, but not ID3v1. This seems unnecessarily
1137 unkind to stupid players.
1140 if f is None: return
1142 if t is None: return
1143 for v in [E3.id3.ID3_V2_3, E3.id3.ID3_V1]:
1144 try: f.tag.save(version = v)
1145 except (UnicodeEncodeError,
1146 E3.id3.GenreException,
1147 E3.id3.TagException):
1150 defformat('mp3', MP3Format)
1152 ###--------------------------------------------------------------------------
1153 ### Image handling, based on the Python Imaging Library.
1155 class ImageIdentifier (object):
1157 Analyses and identifies an image file.
1159 Simply leaves an Image object in the `img' property which can be inspected.
1162 def __init__(me, file, mime):
1164 ## Get PIL to open the file. It will magically work out what kind of
1167 me.img = I.open(file)
1168 except IOError, exc:
1170 ## Unhelpful thing to raise on identification failure. We can
1171 ## distinguish this from an actual I/O error because it doesn't have an
1173 if exc.errno is None:
1174 raise IdentificationFailure
1177 me.mime = set([mime])
1179 class ImageFormat (BaseFormat):
1181 An ImageFormat is a kind of Format specialized for image files.
1183 Subclasses don't need to provide anything other than the properties
1184 required by all concrete Format subclasses. However, there is a
1185 requirement that the `NAME' property match PIL's `format' name for the
1189 PROPS = prop('size', Num)
1190 CATEGORY = FileCategory('image', ['image/*'], ImageIdentifier)
1192 def __init__(me, size = None, **kw):
1194 Initialize an ImageFormat object.
1196 Additional keywords are used when encoding, and may be recognized by
1197 enhanced `check' methods in subclasses.
1203 "Check whether the ImageIdentifier ID matches our requirements."
1204 return id.img.format == me.NAME and \
1205 (me._size is None or
1206 (id.img.size[0] <= me._size and
1207 id.img.size[1] <= me._size))
1209 def convert(me, master, id, target):
1210 "Encode the file MASTER, identified as ID, writing the result to TARGET."
1212 ## Write to a scratch file.
1213 new = target + '.new'
1215 ## The ImageIdentifier already contains a copy of the open file. It
1216 ## would be wasteful not to use it.
1218 STATUS.set(filestatus(master, 'convert to %s' % me.NAME))
1220 ## If there's a stated maximum size then scale the image down to match.
1221 ## But thumbnailing clobbers the original, so take a copy.
1222 if me._size is not None and \
1223 (img.size[0] > me._size or img.size[1] > me._size):
1225 img.thumbnail((me._size, me._size), I.ANTIALIAS)
1227 ## Write the output image.
1228 img.save(new, me.NAME, **me._props)
1230 ## Fix it up if necessary.
1234 OS.rename(new, target)
1237 class JPEGFormat (ImageFormat):
1239 Image format for JPEG (actually JFIF) files.
1241 Interesting properties to set:
1244 If present, take a second pass to select optimal encoder settings.
1247 If present, make a progressive file.
1249 quality Integer from 1--100 (worst to best); default is 75.
1253 PROPS = prop('optimize', None) \
1254 | prop('progressive', None, 'progression') \
1255 | prop('quality', Num)
1257 defformat('jpeg', JPEGFormat)
1259 class PNGFormat (ImageFormat):
1261 Image format for PNG files.
1263 Interesting properties:
1266 If present, make a special effort to minimize the output file.
1270 PROPS = prop('optimize', None)
1272 defformat('png', PNGFormat)
1274 class BMPFormat (ImageFormat):
1276 Image format for Windows BMP files, as used by RockBox.
1278 No additional properties.
1283 defformat('bmp', BMPFormat)
1285 ###--------------------------------------------------------------------------
1286 ### Remaining parsing machinery.
1288 Type = K('type') - Name - D('{') - R(Policy) - D('}')
1289 def build_type(s, l, t):
1291 cat = CATEGORYMAP[t[0]]
1293 raise P.ParseException(s, loc, "Unknown category `%s'" % t[0])
1295 if len(pols) == 1: pol = pols[0]
1296 else: pol = AndPolicy(pols)
1297 pol.setcategory(cat)
1299 Type.setParseAction(build_type)
1302 class TargetJob (object):
1303 def __init__(me, targetdir, policies):
1304 me.targetdir = targetdir
1305 me.policies = policies
1309 Target = K('target') - String - D('{') - R(Type) - D('}')
1310 def build_target(s, l, t):
1311 return TargetJob(t[0], t[1])
1312 Target.setParseAction(build_target)
1314 VARS = { 'master': None }
1315 class VarsJob (object):
1316 def __init__(me, vars):
1319 for k, v in me.vars:
1322 Var = prop('master', String)
1323 Vars = K('vars') - D('{') - R(Var) - D('}')
1324 def build_vars(s, l, t):
1325 return VarsJob(t[0])
1326 Vars.setParseAction(build_vars)
1328 TopLevel = Vars | Target
1329 Config = R(TopLevel)
1330 Config.ignore(P.pythonStyleComment)
1332 ###--------------------------------------------------------------------------
1333 ### The directory grobbler.
1335 def grobble(master, targets, noact = False):
1337 Work through the MASTER directory, writing converted files to TARGETS.
1339 The TARGETS are a list of `TargetJob' objects, each describing a target
1340 directory and a policy to apply to it.
1342 If NOACT is true, then don't actually do anything permanent to the
1346 ## Transform the targets into a more convenient data structure.
1350 tpolmap.append(pmap)
1351 for p in t.policies: pmap.setdefault(p.cat, []).append(p)
1353 ## Keep track of the current position in the master tree.
1356 ## And the files which haven't worked.
1359 def grobble_file(master, pmap, targetdir, cohorts):
1360 ## Convert MASTER, writing the result to TARGETDIR.
1362 ## The COHORTS are actually (CAT, ID, COHORT) triples, where a COHORT is
1363 ## a list of (FILENAME, ID) pairs.
1365 ## Since this function might convert the MASTER file, the caller doesn't
1366 ## know the name of the output files, so we return then as a list.
1369 st_m = OS.stat(master)
1371 ## Work through each category listed and apply its policy.
1372 for cat, id, cohort in cohorts:
1374 ## Go through the category's policies and see if any match. If we fail
1375 ## here, see if there are more categories to try.
1376 for pol in pmap[cat]:
1377 acts = pol.actions(master, targetdir, id, cohort)
1382 ## Work through the targets one by one.
1386 ## Find out whether the target file already exists and is up-to-date
1387 ## with respect to the master. (Caution here with low-resolution
1388 ## timestamps.) If it's OK, then just move on.
1390 st_t = OS.stat(a.target)
1391 if st_m.st_mtime < st_t.st_mtime or \
1392 (st_m.st_ino, st_m.st_dev) == (st_t.st_ino, st_t.st_dev):
1394 except OSError, err:
1395 if err.errno not in (E.ENOENT, E.ENOTDIR):
1398 ## We have real work to do. If there's a current status message,
1399 ## it's the containing directory so flush it so that people know
1403 ## Remove the target. (A hardlink will fail if the target already
1408 except OSError, err:
1409 if err.errno not in (E.ENOENT, E.ENOTDIR):
1412 ## Do whatever it is we decided to do.
1414 STATUS.commit(filestatus(master, a))
1418 ## We're done. Return the names of the targets.
1422 def wrap(masterfile):
1423 ## Handle exceptions found while trying to convert a particular file or
1429 ## Something bad happened. Report the error, but continue. (This list
1430 ## of exceptions needs a lot of work.)
1431 except (IOError, OSError), exc:
1433 STATUS.commit(filestatus(masterfile, 'failed (%s)' % exc))
1434 broken.append((masterfile, exc))
1436 def grobble_dir(master, targets):
1437 ## Recursively convert files in MASTER, writing them to the TARGETS.
1439 ## Keep track of the subdirectories we encounter, because we'll need to
1440 ## do all of those in one go at the end.
1443 ## Work through each target directory in turn.
1444 for target, pmap in zip(targets, tpolmap):
1446 ## Make sure the TARGET exists and is a directory. It's a fundamental
1447 ## assumption of this program that the entire TARGET tree is
1448 ## disposable, so if something exists but isn't a directory, we should
1450 if OS.path.isdir(target):
1453 if OS.path.exists(target):
1454 STATUS.commit(filestatus(target, 'clear nondirectory'))
1457 STATUS.commit(filestatus(target, 'create directory'))
1461 ## Keep a list of things in the target. As we convert files, we'll
1462 ## check them off. Anything left over is rubbish and needs to be
1466 for i in OS.listdir(target):
1467 checklist[i] = False
1468 except OSError, err:
1469 if err.errno not in (E.ENOENT, E.ENOTDIR):
1472 ## Keep track of the files in each category.
1477 ## Work through the master files.
1478 for f in sorted(OS.listdir(master)):
1480 ## If the killswitch has been pulled then stop. The whole idea is
1481 ## that we want to cause a clean shutdown if possible, so we don't
1482 ## want to do it in the middle of encoding because the encoding
1483 ## effort will have been wasted. This is the only place we need to
1484 ## check. If we've exited the loop, then clearing old files will
1485 ## probably be fast, and we'll either end up here when the recursive
1486 ## call returns or we'll be in the same boat as before, clearing old
1487 ## files, only up a level. If worst comes to worst, we'll be killed
1488 ## forcibly somewhere inside `SH.rmtree', and that can continue where
1490 if KILLSWITCH.is_set():
1493 ## Do something with the file.
1494 with wrap(OS.path.join(master, f)) as masterfile:
1496 ## If it's a directory then prepare to grobble it recursively, but
1497 ## don't do that yet.
1498 if OS.path.isdir(masterfile):
1500 done.append(OS.path.join(target, f))
1502 ## Otherwise it's a file. Work out what kind, and stash it under
1503 ## the appropriate categories. Later, we'll apply policy to the
1504 ## files, by category, and work out what to do with them all.
1506 gf = GIO.File(masterfile)
1507 mime = gf.query_info('standard::content-type').get_content_type()
1509 for cat in pmap.iterkeys():
1510 id = cat.identify(masterfile, mime)
1511 if id is None: continue
1512 catmap.setdefault(cat, []).append((masterfile, id))
1513 cats.append((cat, id))
1515 catmap.setdefault(None, []).append((masterfile, id))
1516 todo.append((masterfile, cats))
1518 ## Work through the categorized files to see what actions to do for
1520 for masterfile, cats in todo:
1521 with wrap(masterfile):
1522 done += grobble_file(masterfile, pmap, target,
1523 [(cat, id, catmap[cat]) for cat, id in cats])
1525 ## Check the results off the list so that we don't clear it later.
1527 checklist[OS.path.basename(f)] = True
1529 ## Maybe there's stuff in the target which isn't accounted for. Delete
1530 ## it: either the master has changed, or the policy for this target has
1531 ## changed. Either way, the old files aren't wanted.
1533 if not checklist[f]:
1534 STATUS.commit(filestatus(f, 'clear bogus file'))
1536 bogus = OS.path.join(target, f)
1538 if OS.path.isdir(bogus):
1542 except OSError, err:
1543 if err.errno != E.ENOENT:
1546 ## If there are subdirectories which want processing then do those.
1547 ## Keep the user amused by telling him where we are in the tree.
1548 for d in sorted(subdirs):
1550 STATUS.set('/'.join(dirs))
1551 with wrap(OS.path.join(master, d)) as masterdir:
1553 grobble_dir(masterdir,
1554 [OS.path.join(target, d) for target in targets])
1557 STATUS.set('/'.join(dirs))
1559 ## Right. We're ready to go.
1560 grobble_dir(master, [t.targetdir for t in targets])
1563 ###--------------------------------------------------------------------------
1564 ### Command-line interface.
1566 QUIS = OS.path.basename(SYS.argv[0])
1569 "Report a warning message to the user."
1570 SYS.stderr.write('%s: %s\n' % (QUIS, msg))
1573 "Report a fatal error message to the user."
1577 def parse_opts(args):
1579 Parse command-line arguments in ARGS.
1581 Returns a Grobbler object and the MASTER and TARGET directories to be
1585 ## Build the option parser object.
1586 op = OP.OptionParser(prog = QUIS, version = VERSION,
1587 usage = '%prog [-in] [-t TIMEOUT] [-T TIMEOUT] '
1590 Convert a directory tree of files according to the configuration file
1594 ## Timeout handling.
1595 def cb_time(opt, ostr, arg, op):
1596 m = RX.match(r'\s*(\d+)\s*([dhms]?)\s*', arg)
1598 raise OP.OptionValueerror, 'bad time value `%s\'' % arg
1600 t = int(t) * { '': 1, 's': 1, 'm': 60, 'h': 3600, 'd': 86400 }[u]
1601 setattr(op.values, opt.dest, t)
1602 op.add_option('-t', '--timeout', type = 'string', metavar = 'SECS',
1604 help = 'stop processing nicely after SECS',
1605 action = 'callback', callback = cb_time)
1606 op.add_option('-T', '--timeout-nasty', type = 'string', metavar = 'SECS',
1607 dest = 'timeout_nasty',
1608 help = 'stop processing unpleasantly after further SECS',
1609 action = 'callback', callback = cb_time)
1612 op.add_option('-i', '--interactive', action = 'store_true', dest = 'tty',
1613 help = 'provide progress information')
1614 op.add_option('-n', '--no-act', action = 'store_true', dest = 'noact',
1615 help = 'don\'t actually modify the filesystem')
1618 op.set_defaults(formats = [], noact = False,
1619 timeout = None, timeout_nasty = 300)
1620 opts, args = op.parse_args(args)
1622 ## Check that we got the non-option arguments that we want.
1624 op.error('wrong number of arguments')
1626 ## Act on the options.
1628 STATUS.eyecandyp = True
1629 if opts.timeout is not None:
1630 to = TH.Thread(target = timeout,
1631 args = (opts.timeout, opts.timeout_nasty))
1635 ## Parse the configuration file.
1636 with open(args[0]) as conf:
1637 jobs, = Config.parseFile(conf, True)
1643 if __name__ == '__main__':
1644 opts = parse_opts(SYS.argv[1:])
1645 if 'master' not in VARS:
1646 die("no master directory set")
1647 broken = grobble(VARS['master'], TARGETS, opts.noact)
1649 moan('failed to convert some files:')
1650 for file, exc in broken:
1651 moan('%s: %s' % (file, exc))
1654 ## This is basically a successful completion: we did what we were asked to
1655 ## do. It seems polite to report a message, though.
1657 ## Why don't we have a nonzero exit status? The idea would be that a
1658 ## calling script would be interested that we used up all of our time, and
1659 ## not attempt to convert some other directory as well. But that doesn't
1660 ## quite work. Such a script would need to account correctly for time we
1661 ## had spent even if we complete successfully. And if the script is having
1662 ## to watch the clock itself, it can do that without our help here.
1663 if KILLSWITCH.is_set():
1664 moan('killed by timeout')
1666 ###----- That's all, folks --------------------------------------------------