Check-in source.

README.md

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+Parser and documentation for "pspbrwse.jbf" thumbnail caches generated by the file browsing component of Jasc Paint Shop Pro and Animation Shop.  
+The formats have been fully reverse engineered by studying program output without the use of a decompiler.  
+The format is described in the source file, and mirrored in the binary.  
+
+Scripts exist like [this one](http://www.perlmonks.org/?node_id=225501) which can dump v2 files by scraping for JPEG headers, but as of 2011 I wasn't able to find any full reverse engineering of the format.  
+Code is a simple step-by-step parser which should be easy to reference for adding JBF support in file forensics programs or etc.
+
+Works on all major platforms with a C99 compiler. There is no makefile, simply `make jbfinspect`.
+
+# Thumbnail formats
+V2 files (PSP 6+) simply contain embedded JFIF thumbs. Older formats use two different custom bitmap RLE schemes with a custom implicit palette. For these the tool will decode the RLCs and write a plain bitmap with the palette added.  
+The first format (PSP 3-4) consists of either a run-length prefix followed by a palette index to repeat, or a raw palette entry for values < 192.  
+The second (PSP 5) consists of a run-length prefix followed by color, or a length prefix signalling a series of raw palette entries will follow for values < 128.  
+The parsing logic is thus:
+
+    v1.0-1.1: byte > 0xC0 ? [runlength+0xC0],[color] : [color]
+    v1.3:     byte > 0x80 ? [runlength+0x80],[color] : [length],[colors]...
+
+# Use
+The command line tool can list metadata from the file or dump its contents with a few options including the ability to highlight or dump only thumbnails which no longer exist in the JBF source folder, and the ability to dump thumbs into a path recreated from the original path listed inside the JBF.
+
+# Examples
+List jbf contents, highlighting orphaned thumbnails (ANSI colors)
+
+    jbfinspect -o pspbrwse.jbf
+
+Dump missing thumbs from a jbf into "thumbs"
+
+    jbfinspect -qod thumbs pspbrwse.jbf
+
+Dump every jbf in home into a reconstructed directory tree under "thumbs"
+
+    find ~/ -name "*.jbf" -exec jbfinspect -qrd thumbs {} \;