---
name: "cmgen"
section: "1"
platform: "linux"
package: "libfilament-tools"
version: "1.9.25+dfsg3-1+b2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/cmgen"
---

# cmgen(1)

filament material tools

## NAME

cmgen - filament material tools

## DESCRIPTION

cmgen is a command-line tool for generating SH and mipmap levels from an env map. Cubemaps and equirectangular formats are both supported, automatically detected according to the aspect ratio of the source image.

### Usages:

-

  cmgen \[options\] \<input-file\> cmgen \[options\] \<uv\[N\]\>

### Supported input formats:

-

  PNG, 8 and 16 bits Radiance (.hdr) Photoshop (.psd), 16 and 32 bits OpenEXR (.exr)

## OPTIONS

**--help**, **-h**

-

  Print this message

**--license**

-

  Print copyright and license information

**--quiet**, **-q**

-

  Quiet mode. Suppress all non-error output

**--type**=*\[cubemap*\|equirect\|octahedron\|ktx\], **-t** \[cubemap\|equirect\|octahedron\|ktx\]

-

  Specify output type (default: cubemap)

**--format**=*\[exr*\|hdr\|psd\|rgbm\|rgb32f\|png\|dds\|ktx\], **-f** \[exr\|hdr\|psd\|rgbm\|rgb32f\|png\|dds\|ktx\]

-

  Specify output file format. ktx implies **-type**=*ktx*. KTX files are always encoded with 3-channel RGB\_10\_11\_11\_REV data

**--compression**=*COMPRESSION*, **-c** COMPRESSION

-

  Format specific compression:

-

  KTX:

-

  astc\_\[fast\|thorough\]\_\[ldr\|hdr\]\_WxH, where WxH is a valid block size s3tc\_rgba\_dxt5 etc\_FORMAT\_METRIC\_EFFORT

-

  FORMAT is rgb8\_alpha, srgb8\_alpha, rgba8, or srgb8\_alpha8 METRIC is rgba, rgbx, rec709, numeric, or normalxyz EFFORT is an integer between 0 and 100

-

  PNG: Ignored PNG RGBM: Ignored Radiance: Ignored Photoshop: 16 (default), 32 OpenEXR: RAW, RLE, ZIPS, ZIP, PIZ (default) DDS: 8, 16 (default), 32

**--size**=*power-of-two*, **-s** power-of-two

-

  Size of the output cubemaps (base level), 256 by default Also applies to DFG LUT

**--deploy**=*dir*, **-x** dir

-

  Generate everything needed for deployment into \<dir\>

**--extract**=*dir*

-

  Extract faces of the cubemap into \<dir\>

**--extract-blur**=*roughness*

-

  Blurs the cubemap before saving the faces using the roughness blur

**--clamp**

-

  Clamp environment before processing

**--no-mirror**

-

  Skip mirroring of generated cubemaps (for assets with mirroring already backed in)

**--ibl-samples**=*numSamples*

-

  Number of samples to use for IBL integrations (default 1024)

**--ibl-ld**=*dir*

-

  Roughness pre-filter into \<dir\>

**--sh-shader**

-

  Generate irradiance SH for shader code

### Private use only:

**--ibl-dfg**=*filename*.\[exr\|hdr\|psd\|png\|rgbm\|rgb32f\|dds\|h\|hpp\|c\|cpp\|inc\|txt\]

-

  Compute the IBL DFG LUT

**--ibl-dfg-multiscatter**

-

  If **--ibl-dfg** is set, computes the DFG for multi-scattering GGX

**--ibl-dfg-cloth**

-

  If **--ibl-dfg** is set, adds a 3rd channel to the DFG for cloth shading

**--ibl-is-mipmap**=*dir*

-

  Generate mipmap for pre-filtered importance sampling

**--ibl-irradiance**=*dir*

-

  Diffuse irradiance into \<dir\>

**--ibl-no-prefilter**

-

  Use importance sampling instead of prefiltered importance sampling

**--ibl-min-lod-size**

-

  Minimum LOD size \[default: 16\]

**--sh**=*bands*

-

  SH decomposition of input cubemap

**--sh-output**=*filename*.\[exr\|hdr\|psd\|rgbm\|rgb32f\|png\|dds\|txt\]

-

  SH output format. The filename extension determines the output format

**--sh-irradiance**, **-i**

-

  Irradiance SH coefficients

**--sh-window**=*cutoff*\|no\|auto (default), **-w** cutoff\|no\|auto (default)

-

  SH windowing to reduce ringing

**--debug**, **-d**

-

  Generate extra data for debugging

Cubemaps and equirectangular formats are both supported, automatically detected according to the aspect ratio of the source image.

### Usages:

-

  cmgen \[options\] \<input-file\> cmgen \[options\] \<uv\[N\]\>

### Supported input formats:

-

  PNG, 8 and 16 bits Radiance (.hdr) Photoshop (.psd), 16 and 32 bits OpenEXR (.exr)

**--help**, **-h**

-

  Print this message

**--license**

-

  Print copyright and license information

**--quiet**, **-q**

-

  Quiet mode. Suppress all non-error output

**--type**=*\[cubemap*\|equirect\|octahedron\|ktx\], **-t** \[cubemap\|equirect\|octahedron\|ktx\]

-

  Specify output type (default: cubemap)

**--format**=*\[exr*\|hdr\|psd\|rgbm\|rgb32f\|png\|dds\|ktx\], **-f** \[exr\|hdr\|psd\|rgbm\|rgb32f\|png\|dds\|ktx\]

-

  Specify output file format. ktx implies **-type**=*ktx*. KTX files are always encoded with 3-channel RGB\_10\_11\_11\_REV data

**--compression**=*COMPRESSION*, **-c** COMPRESSION

-

  Format specific compression:

-

  KTX:

-

  astc\_\[fast\|thorough\]\_\[ldr\|hdr\]\_WxH, where WxH is a valid block size s3tc\_rgba\_dxt5 etc\_FORMAT\_METRIC\_EFFORT

-

  FORMAT is rgb8\_alpha, srgb8\_alpha, rgba8, or srgb8\_alpha8 METRIC is rgba, rgbx, rec709, numeric, or normalxyz EFFORT is an integer between 0 and 100

-

  PNG: Ignored PNG RGBM: Ignored Radiance: Ignored Photoshop: 16 (default), 32 OpenEXR: RAW, RLE, ZIPS, ZIP, PIZ (default) DDS: 8, 16 (default), 32

**--size**=*power-of-two*, **-s** power-of-two

-

  Size of the output cubemaps (base level), 256 by default Also applies to DFG LUT

**--deploy**=*dir*, **-x** dir

-

  Generate everything needed for deployment into \<dir\>

**--extract**=*dir*

-

  Extract faces of the cubemap into \<dir\>

**--extract-blur**=*roughness*

-

  Blurs the cubemap before saving the faces using the roughness blur

**--clamp**

-

  Clamp environment before processing

**--no-mirror**

-

  Skip mirroring of generated cubemaps (for assets with mirroring already backed in)

**--ibl-samples**=*numSamples*

-

  Number of samples to use for IBL integrations (default 1024)

**--ibl-ld**=*dir*

-

  Roughness pre-filter into \<dir\>

**--sh-shader**

-

  Generate irradiance SH for shader code

### Private use only:

**--ibl-dfg**=*filename*.\[exr\|hdr\|psd\|png\|rgbm\|rgb32f\|dds\|h\|hpp\|c\|cpp\|inc\|txt\]

-

  Compute the IBL DFG LUT

**--ibl-dfg-multiscatter**

-

  If **--ibl-dfg** is set, computes the DFG for multi-scattering GGX

**--ibl-dfg-cloth**

-

  If **--ibl-dfg** is set, adds a 3rd channel to the DFG for cloth shading

**--ibl-is-mipmap**=*dir*

-

  Generate mipmap for pre-filtered importance sampling

**--ibl-irradiance**=*dir*

-

  Diffuse irradiance into \<dir\>

**--ibl-no-prefilter**

-

  Use importance sampling instead of prefiltered importance sampling

**--ibl-min-lod-size**

-

  Minimum LOD size \[default: 16\]

**--sh**=*bands*

-

  SH decomposition of input cubemap

**--sh-output**=*filename*.\[exr\|hdr\|psd\|rgbm\|rgb32f\|png\|dds\|txt\]

-

  SH output format. The filename extension determines the output format

**--sh-irradiance**, **-i**

-

  Irradiance SH coefficients

**--sh-window**=*cutoff*\|no\|auto (default), **-w** cutoff\|no\|auto (default)

-

  SH windowing to reduce ringing

**--debug**, **-d**

-

  Generate extra data for debugging