WEBGL_compressed_texture_pvrtc extension

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

The WEBGL_compressed_texture_pvrtc extension is part of the WebGL API and exposes four PVRTC compressed texture formats.

Compressed textures reduce the amount of memory needed to store a texture on the GPU, allowing for higher resolution textures or more of the same resolution textures.

WebGL extensions are available using the WebGLRenderingContext.getExtension() method. For more information, see also Using Extensions in the WebGL tutorial.

Note: PVRTC is typically only available on mobile devices with PowerVR chipsets. It is used in all generations of the iPhone, iPod Touch and iPad and supported on certain Android devices that use a PowerVR GPU.

This extension is available to both, WebGL1 and WebGL2 contexts.

Note: On iOS devices, this extension is named WEBKIT_WEBGL_compressed_texture_pvrtc.

Constants

The compressed texture formats are exposed by four constants and can be used in two functions: compressedTexImage2D() (where the height and width parameters must be powers of 2) and compressedTexSubImage2D() (where the height and width parameters must equal the current values of the existing texture and the xoffset and yoffset parameters must be 0).

ext.COMPRESSED_RGB_PVRTC_4BPPV1_IMG

RGB compression in 4-bit mode. One block for each 4×4 pixels.

ext.COMPRESSED_RGBA_PVRTC_4BPPV1_IMG

RGBA compression in 4-bit mode. One block for each 4×4 pixels.

ext.COMPRESSED_RGB_PVRTC_2BPPV1_IMG

RGB compression in 2-bit mode. One block for each 8×4 pixels.

ext.COMPRESSED_RGBA_PVRTC_2BPPV1_IMG

RGBA compression in 2-bit mode. One block for each 8×4 pixels.

Examples

js
const ext = gl.getExtension("WEBGL_compressed_texture_pvrtc");

const texture = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, texture);

gl.compressedTexImage2D(
  gl.TEXTURE_2D,
  0,
  ext.COMPRESSED_RGB_PVRTC_4BPPV1_IMG,
  512,
  512,
  0,
  textureData,
);

Specifications

Specification
WebGL WEBGL_compressed_texture_pvrtc Extension Specification

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
WEBGL_compressed_texture_pvrtc
Chrome – Partial support
Chrome 124 (Release date: 2024-04-16)
footnote Partial support
footnote Supported on macOS only.
Edge – Partial support
Edge 124 (Release date: 2024-04-18)
footnote Partial support
footnote Supported on macOS only.
Firefox – No support
Firefox
footnote No support
Opera – Partial support
Opera 110 (Release date: 2024-05-14)
footnote Partial support
footnote Supported on macOS only.
Safari – Full support
Safari 7 (Release date: 2013-10-22)
footnote Full support
Chrome Android – Full support
Chrome Android 28 (Release date: 2013-07-10)
footnote Full support
Firefox for Android – No support
Firefox for Android
footnote No support
Opera Android – Full support
Opera Android 15 (Release date: 2013-07-08)
footnote Full support
Safari on iOS – Full support
Safari on iOS 7 (Release date: 2013-09-18)
footnote Full support
Samsung Internet – Full support
Samsung Internet 1.5 (Release date: 2013-09-25)
footnote Full support
WebView Android – Full support
WebView Android 4.4 (Release date: 2013-12-09)
footnote Full support
WebView on iOS – Full support
WebView on iOS 7 (Release date: 2013-09-18)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
Partial support
Partial support
No support
No support

See also