Image Capture
gphoto2
gPhoto2 is a free, redistributable, ready to use set of digital camera software applications for Unix-like systems, written by a whole team of dedicated volunteers around the world. It supports more than 1800 cameras.
Installation under Ubuntu is simple:
apt-get install gphoto2 libgphoto2-6 libgphoto2-6-dev
(Optional) Install From Source
Optionally, you could install the latest version from source.
Check the installation script for more details.
Capture an Image
Before you write any code to play with the camera, I recommend checking the capabilities of your camera with gphoto2.
Connect your camera through USB. Unmount the device if it is automatially mounted.
Check if gphoto2 detects the camera.
gphoto2 --auto-detect
You should see output like the following if gphoto2 detected the camera.
Model Port
----------------------------------------------------------
Canon EOS 7D usb:002,003
Check the capabilities of the camera.
gphoto2 --summary
Here is a summary of Canon EOS 7D.
Camera summary:
Manufacturer: Canon Inc.
Model: Canon EOS 7D
Version: 3-2.0.3
Serial Number: 51b7b9f89f2244cea68db8ace79efabe
Vendor Extension ID: 0xb (2.0)
Capture Formats: JPEG
Display Formats: Association/Directory, Script, DPOF, MS AVI, MS Wave, JPEG, CRW, Unknown(b103), Unknown(bf02), Defined Type, Unknown(b104)
Device Capabilities:
File Download, File Deletion, File Upload
No Image Capture, No Open Capture, Canon EOS Capture, Canon EOS Shutter Button
Storage Devices Summary:
store_00010001:
StorageDescription: CF
VolumeLabel: None
Storage Type: Removable RAM (memory card)
Filesystemtype: Digital Camera Layout (DCIM)
Access Capability: Read-Write
Maximum Capability: 15996256256 (15255 MB)
Free Space (Bytes): 14066253824 (13414 MB)
Free Space (Images): -1
Device Property Summary:
Property 0xd402:(read only) (type=0xffff) 'Canon EOS 7D'
Property 0xd407:(read only) (type=0x6) 1
Property 0xd406:(readwrite) (type=0xffff) 'Unknown Initiator'
Property 0xd303:(read only) (type=0x2) 1
Capture an image (if the camera reported image capture support in the summary output.)
gphoto2 --capture-image
The camera will focus (if not set to manual focus), take a picture and show the file locations on camera.
New file is in location /capt0000.jpg on the camera
New file is in location /capt0000.cr2 on the camera
If autofocus fails, you may see errors like
*** Error ***
Canon EOS Capture failed to release: Perhaps no focus?
ERROR: Could not capture image.
ERROR: Could not capture.
Camera USB Modes
DLSRs normally have multiple modes for usb connection. My Canon 350D has two, Print/PTP and PC.
The camera has different capabilities or configurations in different modes.
In Print/PTP mode, gphoto2 --abilities shows
Abilities for camera : Canon EOS 350D
Serial port support : no
USB support : yes
Capture choices :
: Capture not supported by the driver
Configuration support : no
Delete selected files on camera : yes
Delete all files on camera : no
File preview (thumbnail) support : yes
File upload support : yes
gphoto2 --list-config shows
/main/actions/syncdatetime
/main/settings/ownername
/main/settings/capturetarget
/main/settings/capture
/main/status/serialnumber
/main/status/manufacturer
/main/status/cameramodel
/main/status/deviceversion
/main/status/vendorextension
/main/status/model
/main/status/firmwareversion
/main/other/d045
/main/other/d002
/main/other/d003
/main/other/d02c
/main/other/d02d
/main/other/d049
/main/other/d032
/main/other/d031
/main/other/d034
/main/other/d033
/main/other/d02e
/main/other/d02f
/main/other/d046
/main/other/d047
/main/other/d030
/main/other/d04a
In PC mode, the output of gphoto2 --abilities becomes
Abilities for camera : Canon Digital Rebel XT (normal mode)
Serial port support : no
USB support : yes
Capture choices :
: Image
: Preview
Configuration support : yes
Delete selected files on camera : yes
Delete all files on camera : no
File preview (thumbnail) support : yes
File upload support : no
and the output of gphoto2 --list-config turns into
/main/settings/ownername
/main/settings/capturesizeclass
/main/settings/iso
/main/settings/shootingmode
/main/settings/shutterspeed
/main/settings/zoom
/main/settings/aperture
/main/settings/exposurecompensation
/main/settings/imageformat
/main/settings/focusmode
/main/settings/flashmode
/main/settings/beep
/main/actions/syncdatetime
/main/status/model
/main/status/datetime
/main/status/firmwareversion
/main/status/driver
/main/Driver/list_all_files
Note that we have more control of the image capture settings in PC mode. But operations (almost anything that need communication with the device) take longer to complete in this mode. File download speed is also considerably lower compared to Print/PTP mode.