Photo CD
The Kodak Photo CD ( PCD for short ) is a standardized compact disc ( CD -ROM) for digitization and proper storage of photographs.
Description
The photo CD has been developed by Eastman Kodak Company, and based on the Philips CD -I bridge specification and introduced in 1992 in the market; there are versions for both the private and the professional image editing. The specification of the Photo CD ( " Beige Book " ) is in contrast to the other Rainbow Books not only the definition of the media format, but includes a full method to digitize small format negatives and slides in high quality and to save in different resolutions the possibility of ADPCM sound features for the image and a reproduction program.
Applications
The data stored on the Photo CD images can be output from virtually any computer with a CD -ROM drive and appropriate software directly on a screen or printer and edited as needed. Most image viewing programs, as well as Adobe Photoshop can directly open the images in a photo CD. For use in the living room specially players were sold by Kodak and other companies with which the images can be output to a TV.
The distribution of the Kodak Photo CD is strongly declining for years - Kodak has therefore adjusted the support of the product on its website. In addition, nowadays all DVD and Bluray players reflect on appropriate media stored image files through the TV.
Processing
The film is first processed conventionally, and then the individual images are sampled ( digitized ), each pixel is represented by 24 bits ( 8 bits luminance and chrominance 8 bits → YCC ); Here, a normalized illumination used according to the CIE standard D65.
Since the scanning of the images is performed exclusively by the Kodak PCD Imaging Workstation, the photo CD in the home could never prevail. The quality of the Photo CD scans corresponded in the 1990s - provided a good kalibribrierten Scanner - a high quality drum scan.
As a disc only gold-colored CD blanks were used, which were manufactured by Kodak for archival purposes and to guarantee a shelf life of up to one hundred years (compared to having a commercially available CD-R has a life expectancy of about 10 years ).
File Format
A photo CD can store about 100 pictures in IMAGEPAC file format; there is in each file the image in six different resolutions include:
20 x 30 cm
The file format is compatible with IMAGEPAC any of the common image file formats; is a proprietary specification from Kodak, which was developed exclusively for the Photo CD and is freely available since the publication in late 1998.
A major advantage of ImagePacs is in the media-independent color space PhotoYCC. PhotoYCC is optimal for digital archiving and further processing of photographic masters; Black / white and color processing are possible without conversion.
Variants
Kodak Pro Photo CD Master Disc
The Kodak Pro Photo CD Master disc contains 25 pictures in the highest resolution of 6144 x 4096 pixels ( six resolutions per image file Base/16 to 64 base). This type is suitable for 120 roll film, 4 × 5 sheet film, as well as miniature film at elevated resolution requirements. To scan the Kodak Professional PCD 4045 film scanner will be used.
Similar formats
For home users, there are cheaper alternatives as well as the Kodak Picture CD, Fujicolor CD and the ImageCD. However, these do not correspond to the Photo- CD standard, use destructive compression method and are of lower image quality and process quality.