ZBrush-PCX

Pixologic ZBrush PCX

image/vnd.zbrush.pcx Released 1985 · by ZSoft (Format) / Pixologic (MIME Registration)

The image/vnd.zbrush.pcx MIME type represents a vendor-specific registration of the legacy ZSoft PCX (PiCture eXchange) image format, explicitly mapped for Pixologic's (now Maxon) ZBrush digital sculpting software. Structurally, it is identical to a standard PCX file. Historically, before PSD and 32-bit TIFF/EXR became the industry standards, ZBrush heavily utilized the 8-bit grayscale PCX format to import and export alpha brushes, height maps, and basic texture maps due to its simple, lossless Run-Length Encoding (RLE).

3D Graphics & Gaming Production Ready

Technical Specifications

MIME Type

image/vnd.zbrush.pcx

Extensions

.pcx

Container

ZSoft PCX

Compression

Run-Length Encoding (RLE)

Algorithms

ZSoft Run-Length Encoding (RLE)

Color Depth

8-bit (Grayscale), 24-bit (RGB)

Metadata

None

Capabilities

Transparency

Animation

Progressive Loading

Alpha Channel

HDR Support

Official Specification

Aliases: image/x-pcximage/pcx

Magic Bytes & HTTP Headers

File Signature (Magic Bytes)

0A 05 01 08

ASCII: \x0A\x05\x01\x08

HTTP Headers

Content-Type: image/vnd.zbrush.pcx

Content-Type: image/x-pcx

HTML Accept Attribute

accept="image/vnd.zbrush.pcx, image/x-pcx, .pcx"

Browser Support Matrix

Browser	Status	Min Version
Chrome	Not Supported	—
Firefox	Not Supported	—
Safari	Not Supported	—
Edge	Not Supported	—
Internet Explorer	Not Supported	Legacy

Advantages & Limitations

Advantages

Extremely simple, lossless RLE compression makes it trivial to parse and encode programmatically
Universally supported by almost every 2D image editor created since the 1990s

Limitations

Completely obsolete for modern 3D workflows, which require 16-bit or 32-bit floating-point precision (like OpenEXR or TIFF) to avoid stepping artifacts in displacement maps
No support for modern metadata (EXIF/XMP) or native alpha channels
Zero native support in modern web browsers

Developer Code Snippets

import magic
# Libmagic detects the standard PCX header, outputting 'image/x-pcx'. It will not specify the ZBrush vendor type.
print(magic.from_file('alpha_brush.pcx', mime=True)) # Outputs 'image/x-pcx'

const FileType = require('file-type');
const type = await FileType.fromFile('alpha_brush.pcx');
console.log(type.mime); // Generally outputs 'image/x-pcx'. The ZBrush specific MIME is rarely utilized by general sniffers.

import (
    "bytes"
    "net/http"
)
// http.DetectContentType will not natively recognize PCX. A custom check is needed:
// isPCX := len(buf) > 4 && buf[0] == 0x0A && buf[1] <= 0x05 && buf[2] == 0x01

$mime = mime_content_type('alpha_brush.pcx');
echo $mime; // Standard setups will often resolve this to 'image/x-pcx'

File Detection Steps

How to programmatically detect a image/vnd.zbrush.pcx file by reading its raw bytes:

1 Check the first byte for the standard PCX manufacturer ID: 0x0A (10).
2 The second byte indicates the version (e.g., 0x05 for version 3.0, which supports 24-bit color).
3 The third byte indicates encoding (0x01 for RLE).
4 The fourth byte indicates bits per pixel per plane (usually 0x08).

Software Support

Z

ZBrush (Maxon)

A

Adobe Photoshop

GIMP

ImageMagick

Conversion Tools

Share & Embed

Markdown Badge

[![ZBrush-PCX Format](https://freewebptojpg.com/mime/image/zbrush-pcx/badge.svg)](https://freewebptojpg.com/mime/image/zbrush-pcx)

Interactive iframe Widget

<iframe src="https://freewebptojpg.com/mime/image/zbrush-pcx/embed" width="100%" height="280" style="border:1px solid #cbd5e1;border-radius:8px;" title="ZBrush-PCX Specs"></iframe>

JSON API

All data on this page is available as a free, open JSON API. Use it in your project, documentation, or tooling.

GET https://freewebptojpg.com/mime/image/zbrush-pcx.json Open JSON

Free to use

No auth required

CORS enabled

Use from any domain

Cached 24h

Cache-Control headers set

Frequently Asked Questions

Is a ZBrush PCX file different from a standard PCX file?

Structurally, no. It is a standard ZSoft PCX file. Pixologic simply registered the image/vnd.zbrush.pcx MIME type with IANA to ensure proper file association and content negotiation for ZBrush assets (like alpha brushes and textures) within their software ecosystem.

Why did ZBrush use the PCX format?

In the early days of 3D sculpting (early to mid-2000s), PCX was a widely supported, lightweight format that provided simple, lossless Run-Length Encoding (RLE). It was perfect for storing the 8-bit grayscale images ZBrush uses for alpha brushes and basic displacement maps.

Can I open a ZBrush PCX file in Photoshop?

Yes. Because it is a standard PCX file under the hood, Adobe Photoshop, GIMP, ImageMagick, and most standard image editors can open, edit, and save it without any special ZBrush plugins.