diff options
Diffstat (limited to 'src/qcam/assets/shader/bayer_1x_packed.frag')
| -rw-r--r-- | src/qcam/assets/shader/bayer_1x_packed.frag | 43 |
1 files changed, 37 insertions, 6 deletions
diff --git a/src/qcam/assets/shader/bayer_1x_packed.frag b/src/qcam/assets/shader/bayer_1x_packed.frag index d36db8a2..f53f5575 100644 --- a/src/qcam/assets/shader/bayer_1x_packed.frag +++ b/src/qcam/assets/shader/bayer_1x_packed.frag @@ -23,6 +23,40 @@ 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 */ @@ -66,10 +100,7 @@ void main(void) * Add a small number (a few mantissa's LSBs) to avoid float * representation issues. Maybe paranoic. */ - center_bytes.x = BPP_X * center_pixel.x + 0.02; - - const float threshold_l = 0.127 /* fract(BPP_X) * 0.5 + 0.02 */; - const float threshold_h = 0.625 /* 1.0 - fract(BPP_X) * 1.5 */; + center_bytes.x = BPP * center_pixel.x + 0.02; float fract_x = fract(center_bytes.x); @@ -90,14 +121,14 @@ void main(void) * of the previous group of the pixels, move xcoords[0] one * byte back. */ - xcoords[0] += (fract_x < threshold_l) ? -tex_step.x : 0.0; + 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; + 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; |