While File Explorer will allow you to check out a preview of your JPEG or PNG files, anyone who works in Photoshop often will be unable to preview the PSD files, the file extension every Photoshop project saves in. Image resources use several standard ID numbers.There’s just one problem: not every file format that contains image data is compatible. The resource data, described in the sections on the individual resource types. Name: Pascal string, padded to make the size even (a null name consists of two bytes of 0)Īctual size of resource data that follows Image resource IDs contains a list of resource IDs used by Photoshop. They are referred to as resource blocks because they hold data that was stored in the Macintosh’s resource in early versions of Photoshop.The basic structure of image resource blocks is as shown below: Length Image resources are used to store non-pixel data associated with images such as pen tool paths.
PSD FILE EXTENSION SERIES
It starts with a length field, followed by a series of resource blocks. The third section of the file contains image resources. Other applications that read Photoshop files can treat a duotone image as a gray image, and just preserve the contents of the duotone information when reading and writing the file. For Duotone images, color data contains the duotone specification (the format of which is not documented). For Indexed color images, the length is 768 and the color data contains the color table for the image, in non-interleaved order. For all other modes, this section is represented by 4-byte zeroed values. The color mode data section is structured as follows: LengthĬolor mode data is available only for indexed color and duotone as defined by the mode field in the File Header section. Supported values are: Bitmap # 0 Grayscale # 1 Indexed # 2 RGB # 3 CMYK # 4 Multichannel # 7 Duotone # 8 Lab # 9. Supported range is 1 to 30,000.ĭepth: the number of bits per channel. The number of channels in the image, including any alpha channels. Do not try to read the file if the version does not match this value. Do not try to read the file if the signature does not match this value. The file header contains the basic properties of the image.
It also implies that zeroes be written to skipped fields while writing to a file. The five major parts are:įor conformance, data should be written to all these fields in the section, as Photoshop may try to read the entire section. The length markers are usually padded with bytes to round to the nearest 2 or 4 byte interval. It has many length markers that can be used to move from one section to the next. The Photoshop file format is divided into five major parts.
PSD FILE EXTENSION WINDOWS
This implies swapping the short and long integers when reading or writing on Windows platform. PSD File Format Specificationsĭata in a PSD file is stored in big endian byte order. PSD and has a maximum height and width of 30,000 pixels, and a length limit of two gigabytes. Photoshop files have default extension as. PSD files may include image layers, adjustment layers, layer masks, annotations, file information, keywords and other Photoshop-specific elements. PSD, Photoshop Document, represents Adobe Photoshop’s native file format used for graphics designing and development.