git.sesse.net Git - movit/blob - fft_input.cpp

   1 #include <string.h>
   2 #include <assert.h>
   3 #include <epoxy/gl.h>
   4 #include <fftw3.h>
   5
   6 #include "effect_util.h"
   7 #include "fp16.h"
   8 #include "fft_input.h"
   9 #include "resource_pool.h"
  10 #include "util.h"
  11
  12 using namespace std;
  13
  14 namespace movit {
  15
  16 FFTInput::FFTInput(unsigned width, unsigned height)
  17         : texture_num(0),
  18           fft_width(width),
  19           fft_height(height),
  20           convolve_width(width),
  21           convolve_height(height),
  22           pixel_data(NULL)
  23 {
  24         register_int("fft_width", &fft_width);
  25         register_int("fft_height", &fft_height);
  26 }
  27
  28 FFTInput::~FFTInput()
  29 {
  30         if (texture_num != 0) {
  31                 resource_pool->release_2d_texture(texture_num);
  32         }
  33 }
  34
  35 void FFTInput::set_gl_state(GLuint glsl_program_num, const string& prefix, unsigned *sampler_num)
  36 {
  37         glActiveTexture(GL_TEXTURE0 + *sampler_num);
  38         check_error();
  39
  40         if (texture_num == 0) {
  41                 assert(pixel_data != NULL);
  42
  43                 // Do the FFT. Our FFTs should typically be small enough and
  44                 // the data changed often enough that FFTW_ESTIMATE should be
  45                 // quite OK. Otherwise, we'd need to worry about caching these
  46                 // plans (possibly including FFTW wisdom).
  47                 fftw_complex *in = (fftw_complex *)fftw_malloc(sizeof(fftw_complex) * fft_width * fft_height);
  48                 fftw_complex *out = (fftw_complex *)fftw_malloc(sizeof(fftw_complex) * fft_width * fft_height);
  49                 fftw_plan p = fftw_plan_dft_2d(fft_height, fft_width, in, out, FFTW_FORWARD, FFTW_ESTIMATE);
  50
  51                 // Zero pad.
  52                 for (int i = 0; i < fft_height * fft_width; ++i) {
  53                         in[i][0] = 0.0;
  54                         in[i][1] = 0.0;
  55                 }
  56                 for (unsigned y = 0; y < convolve_height; ++y) {
  57                         for (unsigned x = 0; x < convolve_width; ++x) {
  58                                 int i = y * fft_width + x;
  59                                 in[i][0] = pixel_data[y * convolve_width + x];
  60                                 in[i][1] = 0.0;
  61                         }
  62                 }
  63
  64                 fftw_execute(p);
  65
  66                 // Convert to fp16.
  67                 fp16_int_t *kernel = new fp16_int_t[fft_width * fft_height * 2];
  68                 for (int i = 0; i < fft_width * fft_height; ++i) {
  69                         kernel[i * 2 + 0] = fp64_to_fp16(out[i][0]);
  70                         kernel[i * 2 + 1] = fp64_to_fp16(out[i][1]);
  71                 }
  72
  73                 // (Re-)upload the texture.
  74                 texture_num = resource_pool->create_2d_texture(GL_RG16F, fft_width, fft_height);
  75                 glBindTexture(GL_TEXTURE_2D, texture_num);
  76                 check_error();
  77                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
  78                 check_error();
  79                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
  80                 check_error();
  81                 glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  82                 check_error();
  83                 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, fft_width, fft_height, GL_RG, GL_HALF_FLOAT, kernel);
  84                 check_error();
  85                 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
  86                 check_error();
  87                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
  88                 check_error();
  89                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
  90                 check_error();
  91
  92                 fftw_free(in);
  93                 fftw_free(out);
  94                 delete[] kernel;
  95         } else {
  96                 glBindTexture(GL_TEXTURE_2D, texture_num);
  97                 check_error();
  98         }
  99
 100         // Bind it to a sampler.
 101         set_uniform_int(glsl_program_num, prefix, "tex", *sampler_num);
 102         ++*sampler_num;
 103 }
 104
 105 string FFTInput::output_fragment_shader()
 106 {
 107         return string("#define FIXUP_SWAP_RB 0\n#define FIXUP_RED_TO_GRAYSCALE 0\n") +
 108                 read_file("flat_input.frag");
 109 }
 110
 111 void FFTInput::invalidate_pixel_data()
 112 {
 113         if (texture_num != 0) {
 114                 resource_pool->release_2d_texture(texture_num);
 115                 texture_num = 0;
 116         }
 117 }
 118
 119 bool FFTInput::set_int(const std::string& key, int value)
 120 {
 121         if (key == "needs_mipmaps") {
 122                 // We cannot supply mipmaps; it would not make any sense for FFT data.
 123                 return (value == 0);
 124         }
 125         if (key == "fft_width") {
 126                 if (value < int(convolve_width)) {
 127                         return false;
 128                 }
 129                 invalidate_pixel_data();
 130         }
 131         if (key == "fft_height") {
 132                 if (value < int(convolve_height)) {
 133                         return false;
 134                 }
 135                 invalidate_pixel_data();
 136         }
 137         return Effect::set_int(key, value);
 138 }
 139
 140 }  // namespace movit