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Diffstat (limited to 'src/qcam/assets/shader/bayer_1x_packed.frag')
| -rw-r--r-- | src/qcam/assets/shader/bayer_1x_packed.frag | 216 |
1 files changed, 0 insertions, 216 deletions
diff --git a/src/qcam/assets/shader/bayer_1x_packed.frag b/src/qcam/assets/shader/bayer_1x_packed.frag deleted file mode 100644 index f53f5575..00000000 --- a/src/qcam/assets/shader/bayer_1x_packed.frag +++ /dev/null @@ -1,216 +0,0 @@ -/* SPDX-License-Identifier: BSD-2-Clause */ -/* - * Based on the code from http://jgt.akpeters.com/papers/McGuire08/ - * - * Efficient, High-Quality Bayer Demosaic Filtering on GPUs - * - * Morgan McGuire - * - * This paper appears in issue Volume 13, Number 4. - * --------------------------------------------------------- - * Copyright (c) 2008, Morgan McGuire. All rights reserved. - * - * - * Modified by Linaro Ltd for 10/12-bit packed vs 8-bit raw Bayer format, - * and for simpler demosaic algorithm. - * Copyright (C) 2020, Linaro - * - * bayer_1x_packed.frag - Fragment shader code for raw Bayer 10-bit and 12-bit - * packed formats - */ - -#ifdef GL_ES -precision mediump float; -#endif - -/* - * These constants are used to select the bytes containing the HS part of - * the pixel value: - * BPP - bytes per pixel, - * THRESHOLD_L = fract(BPP) * 0.5 + 0.02 - * THRESHOLD_H = 1.0 - fract(BPP) * 1.5 + 0.02 - * Let X is the x coordinate in the texture measured in bytes (so that the - * range is from 0 to (stride_-1)) aligned on the nearest pixel. - * E.g. for RAW10P: - * -------------+-------------------+-------------------+-- - * pixel No | 0 1 2 3 | 4 5 6 7 | ... - * -------------+-------------------+-------------------+-- - * byte offset | 0 1 2 3 4 | 5 6 7 8 9 | ... - * -------------+-------------------+-------------------+-- - * X | 0.0 1.25 2.5 3.75 | 5.0 6.25 7.5 8.75 | ... - * -------------+-------------------+-------------------+-- - * If fract(X) < THRESHOLD_L then the previous byte contains the LS - * bits of the pixel values and needs to be skipped. - * If fract(X) > THRESHOLD_H then the next byte contains the LS bits - * of the pixel values and needs to be skipped. - */ -#if defined(RAW10P) -#define BPP 1.25 -#define THRESHOLD_L 0.14 -#define THRESHOLD_H 0.64 -#elif defined(RAW12P) -#define BPP 1.5 -#define THRESHOLD_L 0.27 -#define THRESHOLD_H 0.27 -#else -#error Invalid raw format -#endif - - -varying vec2 textureOut; - -/* the texture size in pixels */ -uniform vec2 tex_size; -uniform vec2 tex_step; -uniform vec2 tex_bayer_first_red; - -uniform sampler2D tex_y; - -void main(void) -{ - vec3 rgb; - - /* - * center_bytes holds the coordinates of the MS byte of the pixel - * being sampled on the [0, stride-1/height-1] range. - * center_pixel holds the coordinates of the pixel being sampled - * on the [0, width/height-1] range. - */ - vec2 center_bytes; - vec2 center_pixel; - - /* - * x- and y-positions of the adjacent pixels on the [0, 1] range. - */ - vec2 xcoords; - vec2 ycoords; - - /* - * The coordinates passed to the shader in textureOut may point - * to a place in between the pixels if the texture format doesn't - * match the image format. In particular, MIPI packed raw Bayer - * formats don't have a matching texture format. - * In this case align the coordinates to the left nearest pixel - * by hand. - */ - center_pixel = floor(textureOut * tex_size); - center_bytes.y = center_pixel.y; - - /* - * Add a small number (a few mantissa's LSBs) to avoid float - * representation issues. Maybe paranoic. - */ - center_bytes.x = BPP * center_pixel.x + 0.02; - - float fract_x = fract(center_bytes.x); - - /* - * The below floor() call ensures that center_bytes.x points - * at one of the bytes representing the 8 higher bits of - * the pixel value, not at the byte containing the LS bits - * of the group of the pixels. - */ - center_bytes.x = floor(center_bytes.x); - center_bytes *= tex_step; - - xcoords = center_bytes.x + vec2(-tex_step.x, tex_step.x); - ycoords = center_bytes.y + vec2(-tex_step.y, tex_step.y); - - /* - * If xcoords[0] points at the byte containing the LS bits - * of the previous group of the pixels, move xcoords[0] one - * byte back. - */ - xcoords[0] += (fract_x < THRESHOLD_L) ? -tex_step.x : 0.0; - - /* - * If xcoords[1] points at the byte containing the LS bits - * of the current group of the pixels, move xcoords[1] one - * byte forward. - */ - xcoords[1] += (fract_x > THRESHOLD_H) ? tex_step.x : 0.0; - - vec2 alternate = mod(center_pixel.xy + tex_bayer_first_red, 2.0); - bool even_col = alternate.x < 1.0; - bool even_row = alternate.y < 1.0; - - /* - * We need to sample the central pixel and the ones with offset - * of -1 to +1 pixel in both X and Y directions. Let's name these - * pixels as below, where C is the central pixel: - * - * +----+----+----+----+ - * | \ x| | | | - * |y \ | -1 | 0 | +1 | - * +----+----+----+----+ - * | +1 | D2 | A1 | D3 | - * +----+----+----+----+ - * | 0 | B0 | C | B1 | - * +----+----+----+----+ - * | -1 | D0 | A0 | D1 | - * +----+----+----+----+ - * - * In the below equations (0,-1).r means "r component of the texel - * shifted by -tex_step.y from the center_bytes one" etc. - * - * In the even row / even column (EE) case the colour values are: - * R = C = (0,0).r, - * G = (A0 + A1 + B0 + B1) / 4.0 = - * ( (0,-1).r + (0,1).r + (-1,0).r + (1,0).r ) / 4.0, - * B = (D0 + D1 + D2 + D3) / 4.0 = - * ( (-1,-1).r + (1,-1).r + (-1,1).r + (1,1).r ) / 4.0 - * - * For even row / odd column (EO): - * R = (B0 + B1) / 2.0 = ( (-1,0).r + (1,0).r ) / 2.0, - * G = C = (0,0).r, - * B = (A0 + A1) / 2.0 = ( (0,-1).r + (0,1).r ) / 2.0 - * - * For odd row / even column (OE): - * R = (A0 + A1) / 2.0 = ( (0,-1).r + (0,1).r ) / 2.0, - * G = C = (0,0).r, - * B = (B0 + B1) / 2.0 = ( (-1,0).r + (1,0).r ) / 2.0 - * - * For odd row / odd column (OO): - * R = (D0 + D1 + D2 + D3) / 4.0 = - * ( (-1,-1).r + (1,-1).r + (-1,1).r + (1,1).r ) / 4.0, - * G = (A0 + A1 + B0 + B1) / 4.0 = - * ( (0,-1).r + (0,1).r + (-1,0).r + (1,0).r ) / 4.0, - * B = C = (0,0).r - */ - - /* - * Fetch the values and precalculate the terms: - * patterns.x = (A0 + A1) / 2.0 - * patterns.y = (B0 + B1) / 2.0 - * patterns.z = (A0 + A1 + B0 + B1) / 4.0 - * patterns.w = (D0 + D1 + D2 + D3) / 4.0 - */ - #define fetch(x, y) texture2D(tex_y, vec2(x, y)).r - - float C = texture2D(tex_y, center_bytes).r; - vec4 patterns = vec4( - fetch(center_bytes.x, ycoords[0]), /* A0: (0,-1) */ - fetch(xcoords[0], center_bytes.y), /* B0: (-1,0) */ - fetch(xcoords[0], ycoords[0]), /* D0: (-1,-1) */ - fetch(xcoords[1], ycoords[0])); /* D1: (1,-1) */ - vec4 temp = vec4( - fetch(center_bytes.x, ycoords[1]), /* A1: (0,1) */ - fetch(xcoords[1], center_bytes.y), /* B1: (1,0) */ - fetch(xcoords[1], ycoords[1]), /* D3: (1,1) */ - fetch(xcoords[0], ycoords[1])); /* D2: (-1,1) */ - patterns = (patterns + temp) * 0.5; - /* .x = (A0 + A1) / 2.0, .y = (B0 + B1) / 2.0 */ - /* .z = (D0 + D3) / 2.0, .w = (D1 + D2) / 2.0 */ - patterns.w = (patterns.z + patterns.w) * 0.5; - patterns.z = (patterns.x + patterns.y) * 0.5; - - rgb = even_col ? - (even_row ? - vec3(C, patterns.zw) : - vec3(patterns.x, C, patterns.y)) : - (even_row ? - vec3(patterns.y, C, patterns.x) : - vec3(patterns.wz, C)); - - gl_FragColor = vec4(rgb, 1.0); -} |