| | '''OpenGL extension MESA.ycbcr_texture |
| | |
| | This module customises the behaviour of the |
| | OpenGL.raw.GL.MESA.ycbcr_texture to provide a more |
| | Python-friendly API |
| | |
| | Overview (from the spec) |
| | |
| | This extension supports texture images stored in the YCbCr format. |
| | There is no support for converting YCbCr images to RGB or vice versa |
| | during pixel transfer. The texture's YCbCr colors are converted to |
| | RGB during texture sampling, after-which, all the usual per-fragment |
| | operations take place. Only 2D texture images are supported (not |
| | glDrawPixels, glReadPixels, etc). |
| | |
| | A YCbCr pixel (texel) is a 16-bit unsigned short with two components. |
| | The first component is luminance (Y). For pixels in even-numbered |
| | image columns, the second component is Cb. For pixels in odd-numbered |
| | image columns, the second component is Cr. If one were to convert the |
| | data to RGB one would need to examine two pixels from columns N and N+1 |
| | (where N is even) to deduce the RGB color. |
| | |
| | The official definition of this extension is available here: |
| | http://www.opengl.org/registry/specs/MESA/ycbcr_texture.txt |
| | ''' |
| | from OpenGL import platform, constant, arrays |
| | from OpenGL import extensions, wrapper |
| | import ctypes |
| | from OpenGL.raw.GL import _types, _glgets |
| | from OpenGL.raw.GL.MESA.ycbcr_texture import * |
| | from OpenGL.raw.GL.MESA.ycbcr_texture import _EXTENSION_NAME |
| |
|
| | def glInitYcbcrTextureMESA(): |
| | '''Return boolean indicating whether this extension is available''' |
| | from OpenGL import extensions |
| | return extensions.hasGLExtension( _EXTENSION_NAME ) |
| |
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| |
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| | |
