| | '''OpenGL extension OML.subsample |
| | |
| | This module customises the behaviour of the |
| | OpenGL.raw.GL.OML.subsample to provide a more |
| | Python-friendly API |
| | |
| | Overview (from the spec) |
| | |
| | Many video image formats and compression techniques utilize various |
| | component subsamplings, so it is necessary to provide a mechanism to |
| | specify the up- and down-sampling of components as pixel data is |
| | drawn from and read back to the client. Though subsampled components |
| | are normally associated with the video color space, YCrCb, use of |
| | subsampling in OpenGL does not imply a specific color space. Color |
| | space conversion may be performed using other extensions or core |
| | capabilities such as the color matrix. |
| | |
| | This extension defines two new pixel storage formats representing |
| | subsampled data on the client. It is loosely based on the |
| | SGIX_subsample extension, but specifies subsampling with the data |
| | format parameter rather than pixel packing parameters. It also |
| | adds support for CYA subsampled data. |
| | |
| | When pixel data is received from the client and an unpacking |
| | upsampling mode other than PIXEL_SUBSAMPLE_NONE_OML is specified, |
| | upsampling is performed via replication, unless otherwise specified |
| | by UNPACK_RESAMPLE_OML. |
| | |
| | Similarly, when pixel data is read back to the client and a packing |
| | downsampling mode other than PIXEL_SUBSAMPLE_NONE_OML is specified, |
| | downsampling is performed via simple component decimation (point |
| | sampling), unless otherwise specified by PACK_RESAMPLE_OML. |
| | |
| | The official definition of this extension is available here: |
| | http://www.opengl.org/registry/specs/OML/subsample.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.OML.subsample import * |
| | from OpenGL.raw.GL.OML.subsample import _EXTENSION_NAME |
| |
|
| | def glInitSubsampleOML(): |
| | '''Return boolean indicating whether this extension is available''' |
| | from OpenGL import extensions |
| | return extensions.hasGLExtension( _EXTENSION_NAME ) |
| |
|
| |
|
| | |
| | from OpenGL import images as _i |
| | _i.COMPONENT_COUNTS[ GL_FORMAT_SUBSAMPLE_24_24_OML ] = 1 |
| | _i.COMPONENT_COUNTS[ GL_FORMAT_SUBSAMPLE_244_244_OML ] = 1 |
| |
|
