5.2 KiB
Audioextract
Extract audio files that are embedded within other files.
Setup
mkdir build-posix
make
make install PREFIX=/usr
Cross compile for Windows:
mkdir build-win32
make TARGET=win32
Or:
mkdir build-win64
make TARGET=win64
NOTE: 32bit binaries can only process 2 GB of a file at once. The rest of
bigger files will be ignored. You need to run this program several times with
different --offset values to process such a file whole.
This also means that using a 32bit binary extracted files can never be larger than 2 GB.
This is because audioextract uses mmap to read files, wich maps files to
memory. On 32bit the address space of the main memory is simply not big enough.
64bit binaries can read up to 8 EB (8 Exabytes) at once.
Usage
audioextract [option...] <filename> [<filename> ...]
Examples
Extract .wav, .aif and .ogg (might actually be .flac, .opus or .ogm) files from
the file data.bin and store them in the ~/Music directory.
audioextract -f wave,ogg -o ~/Music data.bin
This will then write files like such into ~/Music:
data.bin_00000000.ogg
data.bin_00FFB2E3.wav
data.bin_01F3CD45.aif
The hexadecimal number in the written file names give the offset where in the data file the audio file was found.
Extract .mp3, .mp2 and .mp1 files (with or without ID3v2 tags). The mpg123
option yields a lot of false positives because there is no nice way to
unambigiously detect MPEG files. These false positives are however usually very
small, so using the --min-size one can hopefully extract only real MPEG files.
audioextract -f id3v2,mpg123 --min-size 100k -o ~/Music data.bin
Options
-h, --help Print this help message.
-q, --quiet Do not print status messages.
-o, --output=DIR Directory where extracted files should be written. (default: ".")
-i, --offset=OFFSET Start processing at byte OFFSET. (default: 0)
-n, --length=LENGTH Only process LENGTH bytes.
(default and maximum: 8E)
-m, --min-size=SIZE Minumum size of extracted files (skip smaller). (default: 0)
-x, --max-size=SIZE Maximum size of extracted files (skip larger).
(default and maximum: 16E)
The last character of OFFSET, LENGTH and SIZE may be one of the
following:
B (or none) for Bytes
k for Kilobytes (units of 1024 Bytes)
M for Megabytes (units of 1024 Kilobytes)
G for Gigabytes (units of 1024 Megabytes)
T for Terabytes (units of 1024 Gigabytes)
P for Petabytes (units of 1024 Terabytes)
E for Exabyte (units of 1024 Petabytes)
The special value "max" selects the maximum alowed value.
-f, --formats=FORMATS Comma separated list of formats (file magics) to extract.
Supported formats:
all all supported formats
default the default set of formats (AIFF, ASF, BINK, ID3v2, IT,
MIDI, MP4, Ogg, RIFF, S3M, XM)
aiff big-endian (Apple) wave files
asf Advanced Systems Format files (also WMA and WMV)
bink BINK files
id3v2 MPEG layer 1/2/3 files with ID3v2 tags
it ImpulseTracker files
midi MIDI files
mod Noisetracker/Soundtracker/Protracker Module files
mpg123 MPEG layer 1/2/3 files (MP1, MP2, MP3)
mp4 MP4 files (M4A, M4V, 3GPP etc.)
ogg Ogg files (Vorbis, Opus, Theora, etc.)
riff Resource Interchange File Format files (ANI, AVI, MMM,
PAL, RDI, RMI, WAV)
s3m ScreamTracker III files
xm Extended Module files
tracker all tracker files (MOD, S3M, IT, XM)
WARNING: Because MP1/2/3 files do not have a nice file magic, using
the 'mpg123' format may cause *a lot* of false positives. Nowadays
MP3 files usually have an ID3v2 tag at the start, so using the
'id3v2' format is the better option anyway.
The detection accuracy of MOD files is not much better and thus
they are also per default disabled.
NOTE: When using only the 'mpg123' format but not 'id3v2' any ID3v2
tag will be stripped. ID3v1 tags will still be kept.
If '-' is written before a format name the format will be
removed from the set of formats to extract. E.g. extract
everything except tracker files:
audioextract --formats=all,-tracker data.bin