Las fotografiás contienen metadatos que nos pueden servir de muchas maneras. Para poder visualizar de una manera en Debian Squeeze debemos de seguir algunos pasos muy sencillos.

OBS:

• Ser root.

Entramos a la consola y escribimos:
aptitude install libimage-exiftool-perl

Una vez instalado la herramienta, volvemos a escribir en la consola:
exiftool -all /home/proyectosbeta/Desktop/IMG_3053.JPG


Sale por pantalla:
ExifTool Version Number : 8.15
File Name : IMG_3053.JPG
Directory : /home/proyectosbeta/Desktop
File Size : 3.4 MB
File Modification Date/Time : 2012:12:31 20:40:24-03:00
File Permissions : rw-r--r--
File Type : JPEG
MIME Type : image/jpeg
Exif Byte Order : Little-endian (Intel, II)
Image Description :
Make : Canon
Camera Model Name : Canon PowerShot SX230 HS
Orientation : Horizontal (normal)
X Resolution : 180
Y Resolution : 180
Resolution Unit : inches
Modify Date : 2012:12:31 20:40:25
Y Cb Cr Positioning : Co-sited
Exposure Time : 1/60
F Number : 3.1
ISO : 800
Exif Version : 0230
Date/Time Original : 2012:12:31 20:40:25
Create Date : 2012:12:31 20:40:25
Components Configuration : Y, Cb, Cr, -
Compressed Bits Per Pixel : 3
Shutter Speed Value : 1/60
Aperture Value : 3.1
Max Aperture Value : 3.1
Flash : Auto, Fired, Red-eye reduction
Focal Length : 5.0 mm
Macro Mode : Normal
Self Timer : Off
Quality : Fine
Canon Flash Mode : Red-eye reduction (Auto)
Continuous Drive : Single
Focus Mode : Single
Record Mode : JPEG
Canon Image Size : Large
Easy Mode : Unknown (36)
Digital Zoom : None
Contrast : Normal
Saturation : Normal
Sharpness : 0
Camera ISO : Auto High
Metering Mode : Evaluative
Focus Range : Auto
AF Point : Face Detect
Canon Exposure Mode : Easy
Lens Type : Unknown (-1)
Long Focal : 70 mm
Short Focal : 5 mm
Focal Units : 100/mm
Max Aperture : 3.1
Min Aperture : 8
Flash Bits : E-TTL, Built-in
Focus Continuous : Continuous
AE Setting : Normal AE
Image Stabilization : On
Display Aperture : 3.1
Zoom Source Width : 4000
Zoom Target Width : 4000
Spot Metering Mode : Center
Manual Flash Output : n/a
Auto ISO : 800
Base ISO : 100
Measured EV : 0.16
Target Aperture : 3.1
Target Exposure Time : 1/60
Exposure Compensation : 0
White Balance : Auto
Slow Shutter : Off
Shot Number In Continuous Burst : 0
Optical Zoom Code : 0
Flash Guide Number : 1.34375
Flash Exposure Compensation : 0
Auto Exposure Bracketing : Off
AEB Bracket Value : 0
Control Mode : Camera Local Control
Focus Distance Upper : 0.52
Focus Distance Lower : 0
Bulb Duration : 0
Camera Type : Compact
Auto Rotate : None
ND Filter : Off
Self Timer 2 : 0
Flash Output : 22
Canon Image Type : IMG:PowerShot SX230 HS JPEG
Canon Firmware Version : Firmware Version 1.01
File Number : 108-3053
Owner Name :
Canon Model ID : Unknown (0x3030000)
AF Area Mode : Multi-point AF or AI AF
Num AF Points : 9
Valid AF Points : 9
Canon Image Width : 4000
Canon Image Height : 3000
AF Image Width : 100
AF Image Height : 100
AF Area Widths : 18 18 18 18 18 18 18 18 18
AF Area Heights : 18 18 18 18 18 18 18 18 18
AF Area X Positions : -18 0 18 -18 0 18 -18 0 18
AF Area Y Positions : -18 -18 -18 0 0 0 18 18 18
AF Points In Focus : 1
Primary AF Point : 1
Thumbnail Image Valid Area : 0 0 0 0
Date Stamp Mode : Off
My Color Mode : Off
Firmware Revision : 1.01 rev 3.00
Categories : (none)
Image Unique ID : 6b336324a0e3732be9bb1c94fa3df93b
VRD Offset : 0
User Comment :
Flashpix Version : 0100
Color Space : sRGB
Exif Image Width : 4000
Exif Image Height : 3000
Interoperability Index : R98 - DCF basic file (sRGB)
Interoperability Version : 0100
Related Image Width : 4000
Related Image Height : 3000
Focal Plane X Resolution : 16393.44262
Focal Plane Y Resolution : 16393.44262
Focal Plane Resolution Unit : inches
Sensing Method : One-chip color area
File Source : Digital Camera
Custom Rendered : Normal
Exposure Mode : Auto
Digital Zoom Ratio : 1
Scene Capture Type : Standard
Compression : JPEG (old-style)
Thumbnail Offset : 5632
Thumbnail Length : 5859
Rating : 0
Image Width : 4000
Image Height : 3000
Encoding Process : Baseline DCT, Huffman coding
Bits Per Sample : 8
Color Components : 3
Y Cb Cr Sub Sampling : YCbCr4:2:2 (2 1)
Aperture : 3.1
Flash Exposure Compensation : 0
Drive Mode : Single-frame shooting
Flash Type : Built-In Flash
Image Size : 4000x3000
Lens : 5.0 - 70.0 mm
Lens ID : Unknown 5-70mm
Red Eye Reduction : Off
Scale Factor To 35 mm Equivalent: 5.6
Shooting Mode : Unknown (36)
Shutter Curtain Sync : 1st-curtain sync
Shutter Speed : 1/60
Thumbnail Image : (Binary data 5859 bytes, use -b option to extract)
Circle Of Confusion : 0.005 mm
Field Of View : 65.6 deg
Focal Length : 5.0 mm (35 mm equivalent: 27.9 mm)
Hyperfocal Distance : 1.50 m
Lens : 5.0 - 70.0 mm (35 mm equivalent: 27.9 - 390.9 mm)
Light Value : 6.2


Como pueden darse cuenta, la información es demasiada larga.
Aveces repartimos fotografias por todas partes y no queremos proporcionar muchos datos, entonces para eliminar los metadatos de la fotografía, entramos a la consola y escribimos lo siguiente:
exiftool -all= /home/proyectosbeta/Desktop/IMG_3053.JPG


Sale esto por pantalla:
1 image files updated


Volvemos a escribir en la consola:
exiftool -all /home/proyectosbeta/Desktop/IMG_3053.JPG


Sale esto por pantalla:
ExifTool Version Number : 8.15
File Name : IMG_3053.JPG
Directory : /home/proyectosbeta/Desktop
File Size : 3.4 MB
File Modification Date/Time : 2013:02:16 18:38:00-03:00
File Permissions : rw-r--r--
File Type : JPEG
MIME Type : image/jpeg
Image Width : 4000
Image Height : 3000
Encoding Process : Baseline DCT, Huffman coding
Bits Per Sample : 8
Color Components : 3
Y Cb Cr Sub Sampling : YCbCr4:2:2 (2 1)
Image Size : 4000x3000


Pueden darse cuenta, se eliminaron muchos datos. Ahora si ya podrán repartir sus fotografías sin problema. 🙂
Fuente: Cuaderno de Novato en Debian