Decapod 0.4 Release Notes


The following document are notes on the functionality and behaviour of Decapod 0.4. While there may be some useful information here, we recommend reading the Decapod 0.4 User Guide to start.


  • Decapod 0.4 now uses gphoto v2.4.9 and libgphoto2 v2.4.9.
  • Previously Decapod 0.3 used gphoto2 v2.4.7 and libgphoto2 v2.4.8.


  • Remove memory cards from cameras before using Decapod for best results. Otherwise Ubuntu may try to mount the memory card file system and lock out Decapod.
  • Set cameras to capture in JPG. Other capture formats not supported or tested.
  • Recommend using identical pair of cameras with identical settings for capturing.


  • The Canon PowerShot G10 is the only camera supported in this release because gphoto2 can uniquely identify these cameras by serial numbers. Unique identification of cameras is required to preserve the ordering of left and right pages in the event cameras are disconnected and reconnected during a session.
  • Nikon D50, and Nikon D200 support has been dropped in this release because neither camera reported serial numbers in gphoto2. May be added back in the future.

Camera Setup Interface

New in this release is the Camera Setup interface. This UI detects attached cameras, reports any problems or incompatibility, and then allows the user to test capture using the cameras.

The the cameras are supported, then the user will be able to adjust the rotation and the order of the images.

Capture Interface


  • On first capture, camera detection is performed, there is a slight delay while cameras are detected. User is notified that detection is in process.
  • If only one camera is attached, a user action dialog appears alerting the user to attach a pair of supported cameras.
  • If only one camera is attached, the dialog does not list the camera currently attached. It should.
  • If a pair of cameras are attached, and neither are supported, a dialog should appear to prompt the user to attach supported cameras.
  • If a pair of cameras are attached, and only one is supported, both cameras are listed and indicated whether or not it is supported.
  • If both cameras are supported, the user action dialog does not appear.
  • Picture taking occurs one after the other. This should occur in parallel so both cameras take images at roughly the same time. (

Post Capture Processing

  • Stitching and thumbnail processing executed immediately after capture. This creates a delay between capture time and the time it appears on the UI.
  • Stitching process will create a greyscale stitched image, but leaving the original files unmodified.
  • Thumbnail generation is based on the greyscale stitched image.


  • Export results in a greyscale image PDF with no OCR text or tokenization
  • In some cases pages in a PDF may be colour inverted. This is a known issue and will be fixed in the next release.
  • Exported PDF is created in the following path: ./decapod-0.4/decapod-server/book/pdf/decapod.pdf
  • Export to PDF with tokenization and OCR is not in this release.
  • Export process can take a long time.
  • The PDF generation will omit pages if it does not detect any characters. This may result in multiple pages captured by the user, but a subset of those appearing in the PDF. (
    • Note: some pages may be included in PDF even if it does not have valid characters.