1 /* 2 * Copyright 2010, Google Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: 8 * 9 * * Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * * Redistributions in binary form must reproduce the above 12 * copyright notice, this list of conditions and the following disclaimer 13 * in the documentation and/or other materials provided with the 14 * distribution. 15 * * Neither the name of Google Inc. nor the names of its 16 * contributors may be used to endorse or promote products derived from 17 * this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * This is a semiplanar YUV to RGB conversion shader that uses separate 34 * samplers to hold Y, and UV components. 35 */ 36 37 uniform sampler2D ySampler; 38 uniform sampler2D uvSampler; /* GL_LUMINANCE_ALPHA */ 39 40 #if defined (USE_UNIFORM_MATRIX) 41 uniform mat4 conversion; 42 #endif 43 44 varying vec2 yPlane; 45 varying vec2 uvPlane; 46 47 void main() { 48 float yChannel = texture2D(ySampler, yPlane).r; 49 vec2 uvChannel = texture2D(uvSampler, uvPlane).ra; 50 /* 51 * This does the colorspace conversion from Y'UV to RGB as a matrix 52 * multiply. It also does the offset of the U and V channels from 53 * [0,1] to [-.5,.5] as part of the transform. 54 */ 55 vec4 channels = vec4(yChannel, uvChannel, 1.0); 56 57 #if !defined(USE_UNIFORM_MATRIX) 58 mat4 conversion = mat4( 1.0, 1.0, 1.0, 0.0, 59 0.0, -0.344, 1.772, 0.0, 60 1.402, -0.714, 0.0, 0.0, 61 -0.701, 0.529, -0.886, 1.0); 62 #endif 63 64 gl_FragColor = conversion * channels; 65 } 66
