World Library  
Flag as Inappropriate
Email this Article

Dcraw

Article Id: WHEBN0008667723
Reproduction Date:

Title: Dcraw  
Author: World Heritage Encyclopedia
Language: English
Subject: UFRaw, Rawstudio, Camera Image File Format, Digital Negative, Demosaicing
Collection: Digital Photography, Free Photo Software, Free Software Programmed in C, Photo Software for Linux
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Dcraw

dcraw
dcraw v. 8.99
Original author(s) Dave Coffin
Initial release 5 May 2000 (2000-05-05)[1]
Stable release 9.20 (31 January 2014 (2014-01-31))
Written in ANSI C
Operating system Cross-platform
Platform Platform independent
Available in English and 11 others
Type RAW decoding software
License GPLv2+
Website dcraw website

dcraw is an open-source computer program which is able to read numerous raw image formats, typically produced by high-end digital cameras. dcraw converts these images into the standard PPM and TIFF image formats. This conversion is sometimes referred to as developing a raw image (by analogy with the process of film development) since it renders raw image sensor data (a "digital negative") into a viewable form.

Development began on February 23, 1997. According to the RCS log version 1.0 was released in revision 1.18, on May 5, 2000. Versions up to 3.15 used the name Canon PowerShot Converter, starting with v3.40 the name was Raw Photo Decoder, switching to Raw Photo Decoder "dcraw" in v5.70. Version 8.86 supported 300 cameras.[1]

Contents

  • Motivation 1
  • Design 2
  • GUI frontends 3
  • References 4
  • External links 5

Motivation

While most camera manufacturers supply raw image decoding software for their cameras, this software is almost always proprietary, and often becomes unsupported when a camera model is discontinued. The file formats themselves are often undocumented, and several manufacturers have gone so far as to encrypt all or part of the data in their raw image format, in an attempt to prevent third-party software from accessing it.[2]

Given this ever-expanding plethora of raw image formats, and uncertain and inconsistent support for them by the manufacturers, many photographers worry that their valuable raw images may become unreadable as the applications and operating systems required become obsolete.[3]

In contrast to proprietary decoding software, dcraw strives for simplicity, portability, and consistency, as expressed by its author:

dcraw's open source nature is crucial in assuring this universality: even if its author loses interest in developing the software, or in supporting a particular model of camera, interested users are free to extend it. This helps ensure that it will be possible to decode supported raw image formats far into the future, even after the cameras that produced them are obsolete.

Design

dcraw is written by Dave Coffin in portable ANSI C. Because many raw image formats are specific to one make or model of camera, dcraw is frequently updated to support new models.

For many proprietary raw image formats, dcraw's source code (based largely on reverse-engineering) is the best—or only—publicly available documentation. dcraw currently supports the raw formats of several hundred cameras (including intentionally obfuscated formats).

dcraw is built around the Unix philosophy. The program is a command line tool which takes a list of raw image files to process, along with any image adjustment options desired. This makes dcraw easy to use from shell scripts, but might be harder in multithreaded scenarios. dcraw also serves as the basis for numerous high-level raw image-processing applications (such as viewers and converters), both free and open source software as well as proprietary software.

GUI frontends

Several GUI front-ends for dcraw are available. These applications use dcraw as a back-end to do the actual processing of raw images, but present a graphical interface with which the image processing options can be adjusted.

Multiplatform:

  • darktable, a free RAW developer software for GNU/Linux based operating systems and Mac OS X.
  • iRAW, free GUI based on dcraw.
  • LibRAW DCRAW based library.
  • RawTherapee, a standalone GTK+ raw developer, it uses a tweaked version of dcraw for reading raw photos. It is not just a front-end.
  • UFRaw, a standalone GTK+ application and GIMP plugin.

Unix-like operating systems:

  • Rawstudio, a standalone GTK+ application.
  • dcraw-assist, a KDE-based GUI for dcraw and ImageMagick, supporting ICC-enabled high-quality, web-ready batched RAW conversion.
  • Not So Original, An online image gallery that permits you to manage your workflow and raw photographs with powerful operators.
  • digiKam

Mac OS X:

Microsoft Windows:

  • AZImage Batch and GUI based image converter using LibRAW Lite to read raw formats
  • dcrawnet project on C# port.
  • DNG Viewer by ideaMK is installed as RAW Image Viewer.
  • EasyHDR uses DCRAW to access RAW files.
  • Helicon Filter, Proprietary, can use dcraw for its raw processing.
  • Konvertor uses DCRAW to access RAW files.
  • RAWDrop, Windows frontend.
  • RawTherapee
  • SNS-HDR uses DCRAW to read RAW files.
  • Zero Noise uses DCRAW as development engine to blend several RAW files into a noise free image with expanded dynamic range ideal for HDR.

References

  1. ^ a b Dave Coffin (2014). "dcraw.c,v -- complete unabridged RCS file". Retrieved 2014-03-28.  
  2. ^ "Raw storm in a teacup?". Dpreview.com. 2005-04-27. 
  3. ^ Larry Strunk (2006-03-19). "The RAW Problem".  

External links

  • schnebeck.de, an Interview with Dave Coffin
  • Raw storm in a teacup? Dpreview.com interviews with Dave Coffin, as he outlines some of the roadblocks to reverse-engineering presented by camera manufacturers.
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.