hachoir-strip program

hachoir-strip is an experimental program based on Hachoir library: it removes “useless” informations from a file. Don’t use it to create smaller file, you have better to recompress your data :-) hachoir-strip can be used if you would like to remove spy information which can be used to know the origin of a file.

Examples

Our victim:

$ hachoir-metadata KDE_Click.wav.new
Common:
- Creation date: 2001-02-21   <== here they are
- Producer: Sound Forge 4.5   <== spy informations :-)
- MIME type: audio/x-wav
- Endian: Little endian
Audio:
- Duration: 39 ms
...

Clean up the file:

$ hachoir-strip KDE_Click.wav
[+] Process file KDE_Click.wav
Remove field /info
Remove 56 bytes (3.1%)
Save new file into KDE_Click.wav.new

$ hachoir-metadata KDE_Click.wav.new
Common:
- MIME type: audio/x-wav
- Endian: Little endian
Audio:
- Duration: 39 ms
...

So hachoir-strip removed creation date (2001-02-21) and producer (software used to record/edit the sound: Sound Forge 4.5). The file is also 56 bytes smaller.

Options

You can select field types to remove using –strip:

  • (default): remove all useless fields
  • --strip=useless: remove really useless fields (eg. padding)
  • --strip=metadata: remove metadata like ID3 tags and EXIF and IPTC metadatas
  • --strip=index: remove video index

You can combine options with comma: --strip="useless,metadata".