PCPaint CLP

PCPaint CLP (PCPaint clipping format) is one of the image file formats used by some versions of the PCPaint software for MS-DOS. The image may be uncompressed, or compressed with run-length encoding.

Note that some files with a .clp extension are in PCPaint PIC / Pictor format, and not the CLP format described in this article.

Format
CLP is similar to PIC format, but has a smaller (11- or 13-byte) header, and some other differences:
 * In CLP files, the first two bytes represent the file size. In PIC format, they are always.
 * CLP files never contain palette information.
 * Compressed CLP files have just one RLE block, while PIC files may have multiple blocks.

In pathological cases (if the file size is exactly 0x1234 bytes, and certain other conditions hold), it could be difficult to tell which of these formats a file uses.

Some documentation says that the "bits per pixel" fields contain simply the number of bits per pixel, but evidence suggests the number is actually a code, using the same format as the byte at offset 10 in PIC files.

Software

 * PCPaint 3.1

Sample files

 * GRASP GL files often contain embedded CLP files.
 * https://telparia.com/fileFormatSamples/image/pcPaint/

Links

 * from the Encyclopedia of Graphics File Formats, "Clipping format" section