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authorKovensky <diogomfranco@gmail.com>2012-11-07 11:49:44 -0300
committerwm4 <wm4@nowhere>2012-11-08 00:28:59 +0100
commitfae73079310eef9dce9737f2e37ff4b80c8830ee (patch)
tree4a9c7d9fbc398b237808283df39562e55077a225 /TOOLS
parent58f821e096392e27994102f6de6f8f76c63e38e1 (diff)
downloadmpv-fae73079310eef9dce9737f2e37ff4b80c8830ee.tar.bz2
mpv-fae73079310eef9dce9737f2e37ff4b80c8830ee.tar.xz
Port several python scripts to Perl
file2string.pl and vdpau_functions.pl are direct ports. matroska.py was reimplemented as the Parse::Matroska module in CPAN, and matroska.pl was made a client of Parse::Matroska. A copy of Parse::Matroska is included in TOOLS/lib, and matroska.pl looks there first when trying to load the module. osxbundle.py was not ported since I have no means to verify it. Python is always available on OSX though, so there is no harm in removing the check for it on configure.
Diffstat (limited to 'TOOLS')
-rwxr-xr-xTOOLS/file2string.pl24
-rwxr-xr-xTOOLS/file2string.py27
-rw-r--r--TOOLS/lib/Parse/Matroska.pm30
-rw-r--r--TOOLS/lib/Parse/Matroska/Definitions.pm350
-rw-r--r--TOOLS/lib/Parse/Matroska/Element.pm331
-rw-r--r--TOOLS/lib/Parse/Matroska/Reader.pm423
-rw-r--r--TOOLS/lib/Parse/Matroska/Utils.pm37
-rwxr-xr-xTOOLS/matroska.pl169
-rwxr-xr-xTOOLS/matroska.py429
-rwxr-xr-xTOOLS/vdpau_functions.pl (renamed from TOOLS/vdpau_functions.py)58
10 files changed, 1398 insertions, 480 deletions
diff --git a/TOOLS/file2string.pl b/TOOLS/file2string.pl
new file mode 100755
index 0000000000..d9ad215d6d
--- /dev/null
+++ b/TOOLS/file2string.pl
@@ -0,0 +1,24 @@
+#! /usr/bin/env perl
+
+use strict;
+use warnings;
+
+# Convert the contents of a file into a C string constant.
+# Note that the compiler will implicitly add an extra 0 byte at the end
+# of every string, so code using the string may need to remove that to get
+# the exact contents of the original file.
+# FIXME: why not a char array?
+
+# treat only alphanumeric and not-" punctuation as safe
+my $unsafe_chars = qr{[^][A-Za-z0-9!#%&'()*+,./:;<=>?^_{|}~ -]};
+
+for my $file (@ARGV) {
+ open my $fh, '<:raw', $file or next;
+ print "/* Generated from $file */\n";
+ while (<$fh>) {
+ # replace unsafe chars with their equivalent octal escapes
+ s/($unsafe_chars)/\\@{[sprintf '%03o', ord($1)]}/gos;
+ print "\"$_\"\n"
+ }
+ close $fh;
+}
diff --git a/TOOLS/file2string.py b/TOOLS/file2string.py
deleted file mode 100755
index 6cdd1a72ae..0000000000
--- a/TOOLS/file2string.py
+++ /dev/null
@@ -1,27 +0,0 @@
-#!/usr/bin/env python
-
-# Convert the contents of a file into a C string constant.
-# Note that the compiler will implicitly add an extra 0 byte at the end
-# of every string, so code using the string may need to remove that to get
-# the exact contents of the original file.
-
-import sys
-
-# Indexing a byte string yields int on Python 3.x, and a str on Python 2.x
-def pord(c):
- return ord(c) if type(c) == str else c
-
-def main(infile):
- conv = ['\\' + ("%03o" % c) for c in range(256)]
- safe_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" \
- "0123456789!#%&'()*+,-./:;<=>?[]^_{|}~ "
- for c in safe_chars:
- conv[ord(c)] = c
- for c, esc in ("\nn", "\tt", r"\\", '""'):
- conv[ord(c)] = '\\' + esc
- for line in infile:
- sys.stdout.write('"' + ''.join(conv[pord(c)] for c in line) + '"\n')
-
-with open(sys.argv[1], 'rb') as infile:
- sys.stdout.write("// Generated from %s\n\n" % sys.argv[1])
- main(infile)
diff --git a/TOOLS/lib/Parse/Matroska.pm b/TOOLS/lib/Parse/Matroska.pm
new file mode 100644
index 0000000000..e1c08c9814
--- /dev/null
+++ b/TOOLS/lib/Parse/Matroska.pm
@@ -0,0 +1,30 @@
+use 5.008;
+use strict;
+use warnings;
+
+# ABSTRACT: Module collection to parse Matroska files.
+package Parse::Matroska;
+
+=head1 DESCRIPTION
+
+C<use>s L<Parse::Matroska::Reader>. See the documentation
+of the modules mentioned in L</"SEE ALSO"> for more information
+in how to use this module.
+
+It's intended for this module to contain high-level interfaces
+to the other modules in the distribution.
+
+=head1 SOURCE CODE
+
+L<https://github.com/Kovensky/Parse-Matroska>
+
+=head1 SEE ALSO
+
+L<Parse::Matroska::Reader>, L<Parse::Matroska::Element>,
+L<Parse::Matroska::Definitions>.
+
+=cut
+
+use Parse::Matroska::Reader;
+
+1;
diff --git a/TOOLS/lib/Parse/Matroska/Definitions.pm b/TOOLS/lib/Parse/Matroska/Definitions.pm
new file mode 100644
index 0000000000..9b700a7d20
--- /dev/null
+++ b/TOOLS/lib/Parse/Matroska/Definitions.pm
@@ -0,0 +1,350 @@
+use 5.008;
+use strict;
+use warnings;
+
+# ABSTRACT: internal EBML grammar definitions
+package Parse::Matroska::Definitions;
+
+use Parse::Matroska::Utils qw{uniq uncamelize};
+
+use Exporter;
+our @ISA = qw{Exporter};
+our @EXPORT_OK = qw{elem_by_hexid %EBML_DEFINITION %MATROSKA_DEFINITION};
+
+=head1 SYNOPSIS
+
+ use Parse::Matroska::Definitions qw{elem_by_hexid};
+ my $ebml_id = elem_by_hexid('1a45dfa3');
+ print "EBML ID $ebml_id->{elid}'s name: $ebml_id->{name}";
+
+=head1 DESCRIPTION
+
+Contains the definition of the EBML grammar as expected in
+Matroska files. This module is meant mostly for internal use.
+
+As this was extended from a script in mpv-player, some data
+generated is apparently useless for regular module users
+but is still relevant to the mpv-player script. Such data
+is annotated as being for mpv compatibility.
+
+=head1 NOTE
+
+The API of this module is not yet considered stable.
+
+=head1 GLOBALS
+
+These global variables are considered B<immutable>.
+
+=head2 @Parse::Matroska::Definitions::global_elem_list
+
+A global list of known matroska elements. Useful for
+mpv's matroska script, used for generating C headers
+that parse matroska.
+
+=head2 %Parse::Matroska::Definitions::global_elem_dict
+
+A global hash of known matroska elements. Used internally
+by L</elem_by_hexid($id)>.
+
+=cut
+
+@Parse::Matroska::Definitions::global_elem_list = ();
+%Parse::Matroska::Definitions::global_elem_dict = ();
+
+=head2 %EBML_DEFINITION
+
+Optionally-importable hash of known EBML IDs belonging
+to the EBML generic grammar.
+
+=head2 %MATROSKA_DEFINITION
+
+Optionally-importable hash of known EBML IDs belonging
+to the Matroska-specific grammar.
+
+=cut
+
+our %EBML_DEFINITION = define_ebml();
+our %MATROSKA_DEFINITION = define_matroska();
+
+=method elem_by_hexid($id)
+
+Returns an EBML Element Definition corresponding to the provided
+hexadecimal string. Returns C<undef> if the element is unknown.
+
+=cut
+sub elem_by_hexid {
+ my ($elid) = @_;
+ return $Parse::Matroska::Definitions::global_elem_dict{$elid};
+}
+
+################################################
+### Helper functions for document definition ###
+################################################
+
+# used by elem when setting the 'valname' key
+use constant TYPE_MAP => {
+ uint => 'uint64_t',
+ str => 'struct bstr',
+ binary => 'struct bstr',
+ ebml_id => 'uint32_t',
+ float => 'double',
+ sint => 'int64_t',
+};
+
+# this will be localized to "MATROSKA" or "EBML" on the elem declarations
+our $ELEM_DEFINE_TYPE = undef;
+
+=method elem($name,$elid,$valtype)
+
+NOTE: never call this function yourself; it changes data structures
+that are considered immutable outside of this package.
+
+Internal API function that generates the EBML Element Definitions.
+
+This API function returns an array which first element is C<$elid>
+and the second is a generated hash. The generated hash is stored
+in the @global_elem_list and %global_elem_dict.
+
+The generated hash contains:
+
+=for :list
+= name
+The EBML Element's name, given through C<$name>.
+= elid
+The EBML Element's hex id, given through C<$elid>. Used for lookups by L</elem_by_hexid($id)>.
+= valtype
+The EBML Element's type, given through C<$valtype>, except when C<$valtype> is an arrayref.
+= multiple
+If C<$name> ends with a C<*>, this is set as true and strips the C<*> from L</name>. Used to
+mark elements that may be repeated.
+= subelements
+An arrayref of elements that may be children of this element, given through C<$valtype> if it
+is an arrayref. Sets L</valtype> to C<sub> if there are subelements.
+= subids
+An arrayref listing all the L</elid>s of subelements, C<uniq>ified.
+
+The following elements are for mpv compatibility:
+
+=for :list
+= definename
+Name used for generating C #defines.
+= fieldname
+Name used for generating C struct fields.
+= structname
+Name used for generating C struct names.
+= ebmltype
+A pre-#defined constant to describe the element's type.
+= valname
+Typename used when declaring a struct field referring to this element.
+
+=cut
+sub elem {
+ my %e = (name => shift, elid => shift, valtype => shift);
+
+ # strip * from name, set 'multiple' if there was one
+ $e{multiple} = scalar $e{name} =~ s/\*$//;
+
+ # ELEM_DEFINE_TYPE is either MATROSKA or EBML
+ $e{definename} = "${ELEM_DEFINE_TYPE}_ID_".uc($e{name});
+ $e{fieldname} = uncamelize $e{name};
+ $e{structname} = "ebml_$e{fieldname}";
+
+ if (ref $e{valtype} eq 'HASH') {
+ $e{subelements} = $e{valtype};
+ $e{subids} = uniq map { $_->{elid} } values %{$e{subelements}};
+ $e{valtype} = 'sub';
+ $e{ebmltype} = 'EBML_TYPE_SUBELEMENTS';
+ $e{valname} = "struct $e{structname}";
+ } else {
+ $e{ebmltype} = "EBML_TYPE_\U$e{valtype}";
+ die "Unrecognized value type $e{valtype}" unless
+ defined ($e{valname} = TYPE_MAP->{$e{valtype}});
+ }
+ my $e = \%e;
+ push @Parse::Matroska::Definitions::global_elem_list, $e;
+ $Parse::Matroska::Definitions::global_elem_dict{$e{elid}} = $e;
+ return ($e{elid}, $e);
+}
+
+#############################################
+### EBML and Matroska document definitons ###
+#############################################
+
+=method define_ebml
+
+Internal function that defines the EBML generic grammar.
+
+Must not be called from outside the package.
+
+=cut
+sub define_ebml {
+ local $ELEM_DEFINE_TYPE = 'EBML';
+ return (
+ elem('EBML', '1a45dfa3', {
+ elem('EBMLVersion', '4286', 'uint'),
+ elem('EBMLReadVersion', '42f7', 'uint'),
+ elem('EBMLMaxIDLength', '42f2', 'uint'),
+ elem('EBMLMaxSizeLength', '42f3', 'uint'),
+ elem('DocType', '4282', 'str'),
+ elem('DocTypeVersion', '4287', 'uint'),
+ elem('DocTypeReadVersion', '4285', 'uint'),
+ }),
+
+ elem('CRC32', 'bf', 'binary'),
+ elem('Void', 'ec', 'binary'),
+ );
+}
+
+
+=method define_matroska
+
+Internal function that defines the Matroska-specific EBML grammar.
+
+Must not be called from outside the package.
+
+=cut
+sub define_matroska {
+ local $ELEM_DEFINE_TYPE = 'MATROSKA';
+ return (
+ elem('Segment', '18538067', {
+ elem('SeekHead*', '114d9b74', {
+ elem('Seek*', '4dbb', {
+ elem('SeekID', '53ab', 'ebml_id'),
+ elem('SeekPosition', '53ac', 'uint'),
+ }),
+ }),
+
+ elem('Info*', '1549a966', {
+ elem('SegmentUID', '73a4', 'binary'),
+ elem('PrevUID', '3cb923', 'binary'),
+ elem('NextUID', '3eb923', 'binary'),
+ elem('TimecodeScale', '2ad7b1', 'uint'),
+ elem('DateUTC', '4461', 'sint'),
+ elem('Title', '7ba9', 'str'),
+ elem('MuxingApp', '4d80', 'str'),
+ elem('WritingApp', '5741', 'str'),
+ elem('Duration', '4489', 'float'),
+ }),
+
+ elem('Cluster*', '1f43b675', {
+ elem('Timecode', 'e7', 'uint'),
+ elem('BlockGroup*', 'a0', {
+ elem('Block', 'a1', 'binary'),
+ elem('BlockDuration', '9b', 'uint'),
+ elem('ReferenceBlock*', 'fb', 'sint'),
+ }),
+ elem('SimpleBlock*', 'a3', 'binary'),
+ }),
+
+ elem('Tracks*', '1654ae6b', {
+ elem('TrackEntry*', 'ae', {
+ elem('TrackNumber', 'd7', 'uint'),
+ elem('TrackUID', '73c5', 'uint'),
+ elem('TrackType', '83', 'uint'),
+ elem('FlagEnabled', 'b9', 'uint'),
+ elem('FlagDefault', '88', 'uint'),
+ elem('FlagForced', '55aa', 'uint'),
+ elem('FlagLacing', '9c', 'uint'),
+ elem('MinCache', '6de7', 'uint'),
+ elem('MaxCache', '6df8', 'uint'),
+ elem('DefaultDuration', '23e383', 'uint'),
+ elem('TrackTimecodeScale', '23314f', 'float'),
+ elem('MaxBlockAdditionID', '55ee', 'uint'),
+ elem('Name', '536e', 'str'),
+ elem('Language', '22b59c', 'str'),
+ elem('CodecID', '86', 'str'),
+ elem('CodecPrivate', '63a2', 'binary'),
+ elem('CodecName', '258688', 'str'),
+ elem('CodecDecodeAll', 'aa', 'uint'),
+ elem('Video', 'e0', {
+ elem('FlagInterlaced', '9a', 'uint'),
+ elem('PixelWidth', 'b0', 'uint'),
+ elem('PixelHeight', 'ba', 'uint'),
+ elem('DisplayWidth', '54b0', 'uint'),
+ elem('DisplayHeight', '54ba', 'uint'),
+ elem('DisplayUnit', '54b2', 'uint'),
+ elem('FrameRate', '2383e3', 'float'),
+ }),
+ elem('Audio', 'e1', {
+ elem('SamplingFrequency', 'b5', 'float'),
+ elem('OutputSamplingFrequency', '78b5', 'float'),
+ elem('Channels', '9f', 'uint'),
+ elem('BitDepth', '6264', 'uint'),
+ }),
+ elem('ContentEncodings', '6d80', {
+ elem('ContentEncoding*', '6240', {
+ elem('ContentEncodingOrder', '5031', 'uint'),
+ elem('ContentEncodingScope', '5032', 'uint'),
+ elem('ContentEncodingType', '5033', 'uint'),
+ elem('ContentCompression', '5034', {
+ elem('ContentCompAlgo', '4254', 'uint'),
+ elem('ContentCompSettings', '4255', 'binary'),
+ }),
+ }),
+ }),
+ }),
+ }),
+
+ elem('Cues', '1c53bb6b', {
+ elem('CuePoint*', 'bb', {
+ elem('CueTime', 'b3', 'uint'),
+ elem('CueTrackPositions*', 'b7', {
+ elem('CueTrack', 'f7', 'uint'),
+ elem('CueClusterPosition', 'f1', 'uint'),
+ }),
+ }),
+ }),
+
+ elem('Attachments', '1941a469', {
+ elem('AttachedFile*', '61a7', {
+ elem('FileDescription', '467e', 'str'),
+ elem('FileName', '466e', 'str'),
+ elem('FileMimeType', '4660', 'str'),
+ elem('FileData', '465c', 'binary'),
+ elem('FileUID', '46ae', 'uint'),
+ }),
+ }),
+
+ elem('Chapters', '1043a770', {
+ elem('EditionEntry*', '45b9', {
+ elem('EditionUID', '45bc', 'uint'),
+ elem('EditionFlagHidden', '45bd', 'uint'),
+ elem('EditionFlagDefault', '45db', 'uint'),
+ elem('EditionFlagOrdered', '45dd', 'uint'),
+ elem('ChapterAtom*', 'b6', {
+ elem('ChapterUID', '73c4', 'uint'),
+ elem('ChapterTimeStart', '91', 'uint'),
+ elem('ChapterTimeEnd', '92', 'uint'),
+ elem('ChapterFlagHidden', '98', 'uint'),
+ elem('ChapterFlagEnabled', '4598', 'uint'),
+ elem('ChapterSegmentUID', '6e67', 'binary'),
+ elem('ChapterSegmentEditionUID', '6ebc', 'uint'),
+ elem('ChapterDisplay*', '80', {
+ elem('ChapString', '85', 'str'),
+ elem('ChapLanguage*', '437c', 'str'),
+ elem('ChapCountry*', '437e', 'str'),
+ }),
+ }),
+ }),
+ }),
+ elem('Tags*', '1254c367', {
+ elem('Tag*', '7373', {
+ elem('Targets', '63c0', {
+ elem('TargetTypeValue', '68ca', 'uint'),
+ elem('TargetTrackUID', '63c5', 'uint'),
+ elem('TargetEditionUID', '63c9', 'uint'),
+ elem('TargetChapterUID', '63c4', 'uint'),
+ elem('TargetAttachmentUID', '63c6', 'uint'),
+ }),
+ elem('SimpleTag*', '67c8', {
+ elem('TagName', '45a3', 'str'),
+ elem('TagLanguage', '447a', 'str'),
+ elem('TagString', '4487', 'str'),
+ }),
+ }),
+ }),
+ }),
+ );
+}
+
+1;
diff --git a/TOOLS/lib/Parse/Matroska/Element.pm b/TOOLS/lib/Parse/Matroska/Element.pm
new file mode 100644
index 0000000000..fa0830c11e
--- /dev/null
+++ b/TOOLS/lib/Parse/Matroska/Element.pm
@@ -0,0 +1,331 @@
+use 5.008;
+use strict;
+use warnings;
+
+# ABSTRACT: a mid-level representation of an EBML element
+package Parse::Matroska::Element;
+
+use Carp;
+use List::Util qw{first};
+
+=head1 SYNOPSIS
+
+ use Parse::Matroska::Reader;
+ my $reader = Parse::Matroska::Reader->new($path);
+ my $elem = $reader->read_element;
+
+ print "ID: $elem->{elid}\n";
+ print "Name: $elem->{name}\n";
+ print "Length: $elem->{content_len}\n";
+ print "Type: $elem->{type}\n";
+ print "Child count: ", scalar(@{$elem->all_children}), "\n";
+ if ($elem->{type} eq 'sub') {
+ while (my $chld = $elem->next_child) {
+ print "Child Name: $chld->{name}\n";
+ }
+ } else {
+ print "Value: ", $elem->get_value, "\n";
+ }
+
+=head1 DESCRIPTION
+
+Represents a single Matroska element as decoded by
+L<Parse::Matroska::Reader>. This is essentially a hash
+augmented with functions for delay-loading of binary
+values and children elements.
+
+=head1 NOTE
+
+The API of this module is not yet considered stable.
+
+=attr elid
+
+The EBML Element ID, suitable for passing to
+L<Parse::Matroska::Definitions/elem_by_hexid>.
+
+=attr name
+
+The EBML Element's name.
+
+=attr type
+
+The EBML Element's type. Can be C<uint>, C<sint>,
+C<float>, C<ebml_id>, C<str> or C<binary>. See L</value>
+for details.
+
+Equivalent to
+C<elem_by_hexid($elem-E<gt>{value})-E<gt>{valtype}>.
+
+=attr value
+
+The EBML Element's value. Should be obtained through
+L</get_value>.
+
+Is an unicode string if the L</type> is C<str>, that is,
+the string has already been decoded by L<Encode/decode>.
+
+Is C<undef> if the L</type> is C<binary> and the contents
+were delay-loaded and not yet read. L</get_value> will
+do the delayed load if needed.
+
+Is an arrayref if the L</type> is C<sub>, containing
+the children nodes that were already loaded.
+
+Is a hashref if the L</type> is C<ebml_id>, containing
+the referred element's information as defined in
+L<Parse::Matroska::Definitions>. Calling
+C<elem_by_hexid($elem-E<gt>{value}-E<gt>{elid})> will
+return the same object as $elem->{value}.
+
+=attr full_len
+
+The entire length of this EBML Element, including
+the header's.
+
+=attr size_len
+
+The length of the size marker. Used when calculating
+L</full_len> from L</content_len>
+
+=attr content_len
+
+The length of the contents of this EBML Element,
+which excludes the header.
+
+=attr reader
+
+A weakened reference to the associated
+L<Parse::Matroska::Reader>.
+
+=method new(%hash)
+
+Creates a new Element initialized with the hash
+given as argument.
+
+=cut
+sub new {
+ my $class = shift;
+ my $self = {};
+ bless $self, $class;
+
+ $self->initialize(@_);
+ return $self;
+}
+
+=method initialize(%hash)
+
+Called by L</new> on initialization.
+
+=cut
+sub initialize {
+ my ($self, %args) = @_;
+ for (keys %args) {
+ $self->{$_} = $args{$_};
+ }
+ $self->{depth} = 0 unless $self->{depth};
+}
+
+=method skip
+
+Called by the user to ignore the contents of this EBML node.
+Needed when ignoring the children of a node.
+
+=cut
+sub skip {
+ my ($self) = @_;
+ my $reader = $self->{reader};
+ return unless $reader; # we don't have to skip if there's no reader
+ my $pos = $reader->getpos;
+ croak "Too late to skip, reads were already done"
+ if $pos ne $self->{data_pos};
+ $reader->skip($self->{content_len});
+}
+
+=method get_value($keep_bin)
+
+Returns the value contained by this EBML element.
+
+If the element has children, returns an arrayref to
+the children elements that were already encountered.
+
+If the element's type is C<binary> and the value was
+delay-loaded, does the reading now.
+
+If $keep_bin is true, the delay-loaded data is kept
+as the L</value>, otherwise, further calls to
+C<get_value> will reread the data from the L</reader>.
+
+=cut
+sub get_value {
+ my ($self, $keep_bin) = @_;
+
+ return undef if $self->{type} eq 'skip';
+ return $self->{value} if $self->{value};
+
+ my $reader = $self->{reader} or
+ croak "The associated Reader has been deleted";
+
+ # delay-loaded 'binary'
+ if ($self->{type} eq 'binary') {
+ croak "Cannot seek in the current Reader" unless $self->{data_pos};
+ # seek to the data position...
+ $reader->setpos($self->{data_pos});
+ # read the data, keeping it in value if requested
+ if ($keep_bin) {
+ $self->{value} = $reader->readlen($self->{content_len});
+ return $self->{value};
+ } else {
+ return $reader->readlen($self->{content_len});
+ }
+ }
+}
+
+=method next_child($read_bin)
+
+Builtin iterator; reads and returns the next child element.
+Always returns undef if the type isn't C<sub>.
+
+Returns undef at the end of the iterator and resets itself to
+point to the first element; so calling L</next_child($read_bin)>
+after the iterator returned C<undef> will return the first child.
+
+The optional C<$read_bin> parameter has the children elements
+not delay-load their value if their type is C<binary>.
+
+If all children elements have already been read, return
+each element in-order as would be given by
+L</all_children($recurse,$read_bin)>.
+
+=cut
+sub next_child {
+ my ($self, $read_bin) = @_;
+ return unless $self->{type} eq 'sub';
+
+ if ($self->{_all_children_read}) {
+ my $idx = $self->{_last_child} ||= 0;
+ if ($idx == @{$self->{value}}) {
+ # reset the iterator, returning undef once
+ $self->{_last_child} = 0;
+ return;
+ }
+ my $ret = $self->{value}->[$idx];
+
+ ++$idx;
+ $self->{_last_child} = $idx;
+ return $ret;
+ }
+
+ my $len = defined $self->{remaining_len}
+ ? $self->{remaining_len}
+ : $self->{content_len};
+
+ if ($len == 0) {
+ # we've read all children; switch into $self->{value} iteration mode
+ $self->{_all_children_read} = 1;
+ # return undef since the iterator will reset
+ return;
+ }
+
+ $self->{pos_offset} ||= 0;
+ my $pos = $self->{data_pos};
+ my $reader = $self->{reader} or croak "The associated reader has been deleted";
+ $reader->setpos($pos);
+ $reader->{fh}->seek($self->{pos_offset}, 1) if $pos;
+
+ my $chld = $reader->read_element($read_bin);
+ return undef unless defined $chld;
+ $self->{pos_offset} += $chld->{full_len};
+
+ $self->{remaining_len} = $len - $chld->{full_len};
+
+ if ($self->{remaining_len} < 0) {
+ croak "Child elements consumed $self->{remaining_len} more bytes than parent $self->{name} contained";
+ }
+
+ $chld->{depth} = $self->{depth} + 1;
+ $self->{value} ||= [];
+
+ push @{$self->{value}}, $chld;
+
+ return $chld;
+}
+
+=method all_children($recurse,$read_bin)
+
+Calls L</populate_children($recurse,$read_bin)> on self
+and returns an arrayref with the children nodes.
+
+Both C<$recurse> and C<$read_bin> are optional and default
+to false.
+
+=cut
+sub all_children {
+ my ($self, $recurse, $read_bin) = @_;
+ $self->populate_children($recurse, $read_bin);
+ return $self->{value};
+}
+
+=method children_by_name($name)
+
+Searches in the already read children elements for all
+elements with the EBML name C<$name>. Returns an array
+containing all found elements. On scalar context,
+returns only the first element found.
+
+Croaks if the element's C<type> isn't C<sub>.
+
+=cut
+sub children_by_name {
+ my ($self, $name) = @_;
+ return unless defined wantarray; # don't do work if work isn't wanted
+ croak "Element can't have children" unless $self->{type} eq 'sub';
+
+ my @found = grep { $_->{name} eq $name } @{$self->{value}};
+ return @found if wantarray; # list
+ return shift @found if defined wantarray; # scalar
+}
+
+=method populate_children($recurse,$read_bin)
+
+Populates the internal array of children elements, that is,
+requests that the associated L<Matroska::Parser::Reader> reads
+all children elements. Returns itself.
+
+Returns false if the element's C<type> isn't C<sub>.
+
+If C<$recurse> is provided and is true, the method will call
+itself in the children elements with the same parameters it
+received; this will build a full EBML tree.
+
+If C<$read_bin> is provided and is true, disables delay-loading
+of the contents of C<binary>-type nodes, reading the contents
+to memory.
+
+If both C<$recurse> and C<$read_bin> are true, entire EBML trees
+can be loaded without requiring seeks, thus behaving correctly
+on unseekable streams. If C<$read_bin> is false, the entire EBML
+tree is still loaded, but calling L</get_value> on C<binary>-type
+nodes will produce an error on unseekable streams.
+
+=cut
+sub populate_children {
+ my ($self, $recurse, $read_bin) = @_;
+
+ return unless $self->{type} eq 'sub';
+
+ if (@{$self->{value}} && $recurse) {
+ # only recurse
+ foreach (@{$self->{value}}) {
+ $_->populate_children($recurse, $read_bin);
+ }
+ return $self;
+ }
+
+ while (my $chld = $self->next_child($read_bin)) {
+ $chld->populate_children($recurse, $read_bin) if $recurse;
+ }
+
+ return $self;
+}
+
+1;
diff --git a/TOOLS/lib/Parse/Matroska/Reader.pm b/TOOLS/lib/Parse/Matroska/Reader.pm
new file mode 100644
index 0000000000..47e67ce5f7
--- /dev/null
+++ b/TOOLS/lib/Parse/Matroska/Reader.pm
@@ -0,0 +1,423 @@
+use 5.008;
+use strict;
+use warnings;
+
+# ABSTRACT: a low-level reader for EBML files
+package Parse::Matroska::Reader;
+
+use Parse::Matroska::Definitions qw{elem_by_hexid};
+use Parse::Matroska::Element;
+
+use Carp;
+use Scalar::Util qw{openhandle weaken};
+use IO::Handle;
+use IO::File;
+use List::Util qw{first};
+use Encode;
+
+use constant BIGINT_TRY => 'Pari,GMP,FastCalc';
+use Math::BigInt try => BIGINT_TRY;
+use Math::BigRat try => BIGINT_TRY;
+
+=head1 SYNOPSIS
+
+ use Parse::Matroska::Reader;
+ my $reader = Parse::Matroska::Reader->new($path);
+ $reader->close;
+ $reader->open(\$string_with_matroska_data);
+
+ my $elem = $reader->read_element;
+ print "Element ID: $elem->{elid}\n";
+ print "Element name: $elem->{name}\n";
+ if ($elem->{type} ne 'sub') {
+ print "Element value: $elem->get_value\n";
+ } else {
+ while (my $child = $elem->next_child) {
+ print "Child element: $child->{name}\n";
+ }
+ }
+ $reader->close;
+
+=head1 DESCRIPTION
+
+Reads EBML data, which is used in Matroska files.
+This is a low-level reader which is meant to be used as a backend
+for higher level readers. TODO: write the high level readers :)
+
+=head1 NOTE
+
+The API of this module is not yet considered stable.
+
+=method new
+
+Creates a new reader.
+Calls L</open($arg)> with its arguments if provided.
+
+=cut
+sub new {
+ my $class = shift;
+ my $self = {};
+ bless $self, $class;
+
+ $self->open(@_) if @_;
+ return $self;
+}
+
+=method open($arg)
+
+Creates the internal filehandle. The argument can be:
+
+=for :list
+* An open filehandle or L<IO::Handle> object.
+The filehandle is not C<dup()>ed, so calling L</close> in this
+object will close the given filehandle as well.
+* A scalar containing a path to a file.
+* On perl v5.14 or newer, a scalarref pointing to EBML data.
+For similar functionality in older perls, give an L<IO::String> object
+or the handle to an already C<open>ed scalarref.
+
+=cut
+sub open {
+ my ($self, $arg) = @_;
+ $self->{fh} = openhandle($arg) || IO::File->new($arg, "<:raw")
+ or croak "Can't open $arg: $!";
+}
+
+=method close
+
+Closes the internal filehandle.
+
+=cut
+sub close {
+ my ($self) = @_;
+ $self->{fh}->close;
+ delete $self->{fh};
+}
+
+# equivalent to $self->readlen(1), possibly faster
+sub _getc {
+ my ($self) = @_;
+ my $c = $self->{fh}->getc;
+ croak "Can't do read of length 1: $!" if !defined $c && $!;
+ return $c;
+}
+
+=method readlen($length)
+
+Reads C<$length> bytes from the internal filehandle.
+
+=cut
+sub readlen {
+ my ($self, $len) = @_;
+ my $data;
+ my $readlen = $self->{fh}->read($data, $len);
+ croak "Can't do read of length $len: $!"
+ unless defined $readlen;
+ return $data;
+}
+
+# converts a byte string into an integer
+# we do so by converting the integer into a hex string (big-endian)
+# and then reading the hex-string into an integer
+sub _bin2int($) {
+ my ($bin) = @_;
+ # if the length is larger than 3
+ # the resulting integer might be larger than INT_MAX
+ if (length($bin) > 3) {
+ return Math::BigInt->from_hex(unpack("H*", $bin));
+ }
+ return hex(unpack("H*", $bin));
+}
+
+# creates a floating-point number with the given mantissa and exponent
+sub _ldexp {
+ my ($mantissa, $exponent) = @_;
+ return $mantissa * Math::BigRat->new(2)**$exponent;
+}
+
+# NOTE: the read_* functions are hard to read because t