Seattle FilmWorks
From Just Solve the File Format Problem
Seattle FilmWorks, later renamed PhotoWorks, was a mail order film processing company. Digitized photographs made by the company used a family of proprietary raster image formats known as SFW and PWP (PhotoWorks PhotoMail). The most common formats are based on JPEG, and can be converted to JPEG format without further loss of image quality.
There are at least three different SFW formats, and one PWP format. The are also at least two other related formats that don't directly contain images: .pwm and .alb.
By 2003 PhotoWorks stopped using the SFW format.[1]
Contents |
Formats
| Format | Signature | Notes |
|---|---|---|
| "SFW93A" SFW, .#?? | SFW93A |
Used briefly, up to sometime in 1994. File extension may be .#??, where ?? is the picture number from the camera roll. |
| "SFW94A" SFW, compressed | SFW94A |
Based on JPEG. The most widely supported format. |
| "SFW94A" SFW, uncompressed | Based on BMP. | |
| .pwm | Not an image format. | |
| PWP | SFW95B |
Container format for multiple SFW images. |
| "SFW98A" SFW | SFW98A |
Based on JPEG with arithmetic coding. Caution: Some utilities reportedly extract only the thumbnail image. |
| .alb | SFW_ALB |
Not an image format. |
Identification
Files begin with an ASCII signature (see the Formats section), but it's not always sufficient to determine the specific format.
The sfwwhichfmt.c utility listed in the Software section below may be helpful.
Screenshots
Software
- PhotoWorks Desktop software version 2.41 for Windows 95/98
- jonesrh .sfw conversion portal - Has information about conversion software
- sfwwhichfmt.c - Utility to display information about SFW/PWP files.
- File format conversion software for Seattle FilmWorks products → sfwjpg-unix.tar (from archive.org)
- SFWJPG (Windows version of sfwjpg-unix.tar)
- ImageMagick
- Konvertor
- XnView
