Kodak Photo CD

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Photo CD player for the living room: Kodak PCD-860 from 1994

The Kodak Photo CD (PCD for short) is a standardized compact disc ( CD-ROM ) for the digitization and appropriate archiving of photographs .

description

Photo CD from 1998

The Photo CD was developed by the Eastman Kodak Company and Philips on the basis of the CD-i-Bridge specification and launched on the market in 1992; there are variants for both private and professional image processing . The specification of the Photo-CD ( " Beige Book "), in contrast to the other Rainbow Books not only the definition of media format , but includes a complete process to small picture - Negative - and slides to digitize high-quality and in different resolutions save, the possibility of ADPCM sound descriptions for the images and a playback program.

A sampler CD with 24 professional photos by various photographers, mostly by Don Cochran, was available for demonstration purposes. She was also part of the Bonus Pak s of OS / 2 Warp .

Applications

The images stored on the Photo CD can be output directly to a screen or printer from almost any computer with a CD-ROM drive and suitable software and edited if necessary. Most image viewing programs as well as Adobe Photoshop can open the images on a Photo CD directly. For use in the living room, Kodak and other companies sold playback devices that can be used to output the images on a television. In countries with a TV refresh rate of 50 Hertz (corresponding to 25 Hz frame rate ; mainly common in Europe / Asia), there was significant large area flickering when displaying photos, i.e. still images, on the picture tubes used in the past; in the 60 Hertz countries, the coarse grid of the only 480 visible image lines due to the M standard (usually referred to as NTSC countries in everyday life). Since this type of device was usually designed for the signal quality possible with analog TV , a large part of the details contained in the photos remained hidden from the viewer on the TV tube.

The distribution of the Kodak Photo CD has been declining for years - Kodak has therefore stopped supporting the product on its homepage. In addition, nowadays all DVD and Blu-ray players can play image files stored on corresponding data carriers on the television.

processing

The film is first developed conventionally and then the individual images are scanned (digitized), with each pixel being represented by 24 bits (8 bits of luminance and 8 bits of chrominance → YCC ); standardized lighting according to the CIE D65 standard is used.

Since the images are scanned exclusively using the Kodak PCD Imaging Workstation , the Photo CD has never caught on in the home. In the 1990s, the quality of the Photo CD scans - assuming a well-calibrated scanner - corresponded to a high-quality drum scan .

As media only golden were blank CDs used were manufactured by Kodak for archival purposes and are intended to guarantee up to one hundred years of life (compared to a commercially available CD-R has a life expectancy of about ten years).

File format

A Photo CD can store up to 100 images in the ImagePac file format; Each image can be decoded in five (Photo CD) or six (Photo CD Pro Master, max. 25 images per CD) different resolutions:

designation Resolution in pixels
( megapixels ) 		Uncompressed file size
[MB] 		use
Base / 16 128 × 192
(<0.1) 		0.07 Index print,
thumbnail
Base / 4 256 × 384
(0.1) 		0.28 Presentation on television,
web
base 512 × 768
(0.4) 		1.13 Presentation on computer monitor,
web
4 base 1024 × 1536
(1.6) 		4.50 Display on HDTV monitor
16 base 2048 × 3072
(6.3) 		18.00 Exposure on paper up to
approx. 20 cm × 30 cm
64 base
(optional) 		4096 × 6144
(25.2) 		72.00 Prepress, printing, archiving

The ImagePac file format is not compatible with any of the popular image file formats; it is a proprietary specification from Kodak that was developed exclusively for the Photo CD and has been freely accessible since its publication in late 1998.

One of the main advantages of ImagePacs is the media-neutral PhotoYCC color space . PhotoYCC is ideal for digital archiving and further processing of photographic originals; Black and white and color editing are possible without conversion .

variants

Kodak Pro Photo CD Master Disc

The Kodak Pro Photo CD Master Disc contains 25 images with a maximum resolution of 6144 × 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 35mm film with increased demands on the resolution. The Kodak Professional PCD Film Scanner 4045 is used for scanning .

Similar formats

For private users there are also the Kodak Picture CD , the Fujicolor CD and the ImageCD as cheaper alternatives . However, these do not comply with the Photo CD standard, use destructive compression methods and are of poor image and process quality.

literature

  • Heinz-W. Bülow, Dirk Paulißen: The big book for the Kodak Photo CD. Data-Becker, Düsseldorf 1993, ISBN 3-89011-642-6
  • Thomas W. Lipp: Graphic formats. Microsoft Press, Unterschleißheim 1997, ISBN 3-86063-391-0

Web links