CC=@CC@
CXX=@CXX@
-CXXFLAGS=-Wall @CXXFLAGS@ -I$(GTEST_DIR)/include @SDL2_CFLAGS@ @SDL_CFLAGS@ @Eigen3_CFLAGS@ @epoxy_CFLAGS@
+CXXFLAGS=-Wall @CXXFLAGS@ -I$(GTEST_DIR)/include @SDL2_CFLAGS@ @SDL_CFLAGS@ @Eigen3_CFLAGS@ @epoxy_CFLAGS@ @FFTW3_CFLAGS@
ifeq ($(with_SDL2),yes)
CXXFLAGS += -DHAVE_SDL2
endif
-LDFLAGS=@epoxy_LIBS@ @SDL2_LIBS@ @SDL_LIBS@ -lpthread
-DEMO_LDLIBS=@SDL2_image_LIBS@ @SDL_image_LIBS@ -lrt -lpthread @libpng_LIBS@
+LDFLAGS=@epoxy_LIBS@ @SDL2_LIBS@ @SDL_LIBS@ @FFTW3_LIBS@ -lpthread
+DEMO_LDLIBS=@SDL2_image_LIBS@ @SDL_image_LIBS@ -lrt -lpthread @libpng_LIBS@ @FFTW3_LIBS@
SHELL=@SHELL@
LIBTOOL=@LIBTOOL@ --tag=CXX
RANLIB=ranlib
TESTED_EFFECTS += slice_effect
TESTED_EFFECTS += complex_modulate_effect
TESTED_EFFECTS += luma_mix_effect
+TESTED_EFFECTS += fft_convolution_effect
UNTESTED_EFFECTS = sandbox_effect
UNTESTED_EFFECTS += mirror_effect
UNTESTED_EFFECTS += resize_effect
UNTESTED_EFFECTS += multiply_effect
+UNTESTED_EFFECTS += fft_input
EFFECTS = $(TESTED_EFFECTS) $(UNTESTED_EFFECTS)
Still TL;DR, please give me the list of filters
===============================================
-Blur, diffusion, glow, lift/gamma/gain (color correction), mirror,
-mix (add two inputs), overlay (the Porter-Duff “over” operation),
-scale (bilinear and Lanczos), sharpen (both by unsharp mask and by
-Wiener filters), saturation (or desaturation), vignette, and white balance.
+Blur, diffusion, FFT-based convolution, glow, lift/gamma/gain (color
+correction), mirror, mix (add two inputs), luma mix (use a map to wipe between
+two inputs), overlay (the Porter-Duff “over” operation), scale (bilinear and
+Lanczos), sharpen (both by unsharp mask and by Wiener filters), saturation
+(or desaturation), vignette, and white balance.
Yes, that's a short list. But they all look great, are fast and don't give
you any nasty surprises. (I'd love to include denoise, deinterlace and
AC_PROG_CXX
PKG_CHECK_MODULES([Eigen3], [eigen3])
PKG_CHECK_MODULES([epoxy], [epoxy])
+PKG_CHECK_MODULES([FFTW3], [fftw3])
# Needed for unit tests and the demo app. We prefer SDL2 if possible,
# but can also use classic SDL.
--- /dev/null
+#include <epoxy/gl.h>
+#include <string.h>
+
+#include "complex_modulate_effect.h"
+#include "effect_chain.h"
+#include "fft_convolution_effect.h"
+#include "fft_input.h"
+#include "fft_pass_effect.h"
+#include "multiply_effect.h"
+#include "padding_effect.h"
+#include "slice_effect.h"
+#include "util.h"
+
+using namespace std;
+
+namespace movit {
+
+FFTConvolutionEffect::FFTConvolutionEffect(int input_width, int input_height, int convolve_width, int convolve_height)
+ : input_width(input_width),
+ input_height(input_height),
+ convolve_width(convolve_width),
+ convolve_height(convolve_height),
+ fft_input(new FFTInput(convolve_width, convolve_height)),
+ crop_effect(new PaddingEffect()),
+ owns_effects(true) {
+ CHECK(crop_effect->set_int("width", input_width));
+ CHECK(crop_effect->set_int("height", input_height));
+ CHECK(crop_effect->set_float("top", 0));
+ CHECK(crop_effect->set_float("left", 0));
+}
+
+FFTConvolutionEffect::~FFTConvolutionEffect()
+{
+ if (owns_effects) {
+ delete fft_input;
+ delete crop_effect;
+ }
+}
+
+namespace {
+
+// Returns the last Effect in the new chain.
+Effect *add_overlap_and_fft(EffectChain *chain, Effect *last_effect, int fft_size, int pad_size, FFTPassEffect::Direction direction)
+{
+ // Overlap.
+ {
+ Effect *overlap_effect = chain->add_effect(new SliceEffect(), last_effect);
+ CHECK(overlap_effect->set_int("input_slice_size", fft_size - pad_size));
+ CHECK(overlap_effect->set_int("output_slice_size", fft_size));
+ CHECK(overlap_effect->set_int("offset", -pad_size));
+ if (direction == FFTPassEffect::HORIZONTAL) {
+ CHECK(overlap_effect->set_int("direction", SliceEffect::HORIZONTAL));
+ } else {
+ assert(direction == FFTPassEffect::VERTICAL);
+ CHECK(overlap_effect->set_int("direction", SliceEffect::VERTICAL));
+ }
+
+ last_effect = overlap_effect;
+ }
+
+ // FFT.
+ int num_passes = ffs(fft_size) - 1;
+ for (int i = 1; i <= num_passes; ++i) {
+ Effect *fft_effect = chain->add_effect(new FFTPassEffect(), last_effect);
+ CHECK(fft_effect->set_int("pass_number", i));
+ CHECK(fft_effect->set_int("fft_size", fft_size));
+ CHECK(fft_effect->set_int("direction", direction));
+ CHECK(fft_effect->set_int("inverse", 0));
+
+ last_effect = fft_effect;
+ }
+
+ return last_effect;
+}
+
+// Returns the last Effect in the new chain.
+Effect *add_ifft_and_discard(EffectChain *chain, Effect *last_effect, int fft_size, int pad_size, FFTPassEffect::Direction direction)
+{
+ // IFFT.
+ int num_passes = ffs(fft_size) - 1;
+ for (int i = 1; i <= num_passes; ++i) {
+ Effect *fft_effect = chain->add_effect(new FFTPassEffect(), last_effect);
+ CHECK(fft_effect->set_int("pass_number", i));
+ CHECK(fft_effect->set_int("fft_size", fft_size));
+ CHECK(fft_effect->set_int("direction", direction));
+ CHECK(fft_effect->set_int("inverse", 1));
+
+ last_effect = fft_effect;
+ }
+
+ // Discard.
+ {
+ Effect *discard_effect = chain->add_effect(new SliceEffect(), last_effect);
+ CHECK(discard_effect->set_int("input_slice_size", fft_size));
+ CHECK(discard_effect->set_int("output_slice_size", fft_size - pad_size));
+ if (direction == FFTPassEffect::HORIZONTAL) {
+ CHECK(discard_effect->set_int("direction", SliceEffect::HORIZONTAL));
+ } else {
+ assert(direction == FFTPassEffect::VERTICAL);
+ CHECK(discard_effect->set_int("direction", SliceEffect::VERTICAL));
+ }
+ CHECK(discard_effect->set_int("offset", pad_size));
+
+ last_effect = discard_effect;
+ }
+
+ return last_effect;
+}
+
+} // namespace
+
+void FFTConvolutionEffect::rewrite_graph(EffectChain *chain, Node *self)
+{
+ int pad_width = convolve_width - 1;
+ int pad_height = convolve_height - 1;
+
+ // Try all possible FFT widths and heights to see which one is the
+ // cheapest. As a proxy for real performance, we use number of texel
+ // fetches; this isn't perfect by any means, but it's easy to work with
+ // and should be approximately correct.
+ int min_x = next_power_of_two(1 + pad_width);
+ int min_y = next_power_of_two(1 + pad_height);
+ int max_y = next_power_of_two(input_height + pad_width);
+ int max_x = next_power_of_two(input_width + pad_height);
+
+ size_t best_cost = numeric_limits<size_t>::max();
+ int best_x = -1, best_y = -1, best_x_before_y_fft = -1, best_x_before_y_ifft = -1;
+
+ // Try both
+ //
+ // overlap(X), FFT(X), overlap(Y), FFT(Y), modulate, IFFT(Y), discard(Y), IFFT(X), discard(X) and
+ // overlap(Y), FFT(Y), overlap(X), FFT(X), modulate, IFFT(X), discard(X), IFFT(Y), discard(Y)
+ //
+ // For simplicity, call them the XY-YX and YX-XY orders. In theory, we
+ // could have XY-XY and YX-YX orders as well, and I haven't found a
+ // convincing argument that they will never be optimal (although it
+ // sounds odd and should be rare), so we test all four possible ones.
+ //
+ // We assume that the kernel FFT is for free, since it is typically done
+ // only once and per frame.
+ for (int x_before_y_fft = 0; x_before_y_fft <= 1; ++x_before_y_fft) {
+ for (int x_before_y_ifft = 0; x_before_y_ifft <= 1; ++x_before_y_ifft) {
+ for (int y = min_y; y <= max_y; y *= 2) {
+ int y_pixels_per_block = y - pad_height;
+ int num_vertical_blocks = div_round_up(input_height, y_pixels_per_block);
+ size_t output_height = y * num_vertical_blocks;
+ for (int x = min_x; x <= max_x; x *= 2) {
+ int x_pixels_per_block = x - pad_width;
+ int num_horizontal_blocks = div_round_up(input_width, x_pixels_per_block);
+ size_t output_width = x * num_horizontal_blocks;
+
+ size_t cost = 0;
+
+ if (x_before_y_fft) {
+ // First, the cost of the horizontal padding.
+ cost = output_width * input_height;
+
+ // log(X) FFT passes. Each pass reads two inputs per pixel,
+ // plus the support texture.
+ cost += (ffs(x) - 1) * 3 * output_width * input_height;
+
+ // Now, horizontal padding.
+ cost += output_width * output_height;
+
+ // log(Y) FFT passes, now at full resolution.
+ cost += (ffs(y) - 1) * 3 * output_width * output_height;
+ } else {
+ // First, the cost of the vertical padding.
+ cost = input_width * output_height;
+
+ // log(Y) FFT passes. Each pass reads two inputs per pixel,
+ // plus the support texture.
+ cost += (ffs(y) - 1) * 3 * input_width * output_height;
+
+ // Now, horizontal padding.
+ cost += output_width * output_height;
+
+ // log(X) FFT passes, now at full resolution.
+ cost += (ffs(x) - 1) * 3 * output_width * output_height;
+ }
+
+ // The actual modulation. Reads one pixel each from two textures.
+ cost += 2 * output_width * output_height;
+
+ if (x_before_y_ifft) {
+ // log(X) IFFT passes.
+ cost += (ffs(x) - 1) * 3 * output_width * output_height;
+
+ // Discard horizontally.
+ cost += input_width * output_height;
+
+ // log(Y) IFFT passes.
+ cost += (ffs(y) - 1) * 3 * input_width * output_height;
+
+ // Discard horizontally.
+ cost += input_width * input_height;
+ } else {
+ // log(Y) IFFT passes.
+ cost += (ffs(y) - 1) * 3 * output_width * output_height;
+
+ // Discard vertically.
+ cost += output_width * input_height;
+
+ // log(X) IFFT passes.
+ cost += (ffs(x) - 1) * 3 * output_width * input_height;
+
+ // Discard horizontally.
+ cost += input_width * input_height;
+ }
+
+ if (cost < best_cost) {
+ best_x = x;
+ best_y = y;
+ best_x_before_y_fft = x_before_y_fft;
+ best_x_before_y_ifft = x_before_y_ifft;
+ best_cost = cost;
+ }
+ }
+ }
+ }
+ }
+
+ const int fft_width = best_x, fft_height = best_y;
+
+ assert(self->incoming_links.size() == 1);
+ Node *last_node = self->incoming_links[0];
+ self->incoming_links.clear();
+ last_node->outgoing_links.clear();
+
+ // Do FFT.
+ Effect *last_effect = last_node->effect;
+ if (best_x_before_y_fft) {
+ last_effect = add_overlap_and_fft(chain, last_effect, fft_width, pad_width, FFTPassEffect::HORIZONTAL);
+ last_effect = add_overlap_and_fft(chain, last_effect, fft_height, pad_height, FFTPassEffect::VERTICAL);
+ } else {
+ last_effect = add_overlap_and_fft(chain, last_effect, fft_height, pad_height, FFTPassEffect::VERTICAL);
+ last_effect = add_overlap_and_fft(chain, last_effect, fft_width, pad_width, FFTPassEffect::HORIZONTAL);
+ }
+
+ // Normalizer.
+ Effect *multiply_effect;
+ float fft_size = fft_width * fft_height;
+ float factor[4] = { 1.0f / fft_size, 1.0f / fft_size, 1.0f / fft_size, 1.0f / fft_size };
+ last_effect = multiply_effect = chain->add_effect(new MultiplyEffect(), last_effect);
+ CHECK(multiply_effect->set_vec4("factor", factor));
+
+ // Multiply by the FFT of the convolution kernel.
+ CHECK(fft_input->set_int("fft_width", fft_width));
+ CHECK(fft_input->set_int("fft_height", fft_height));
+ chain->add_input(fft_input);
+ owns_effects = false;
+
+ Effect *modulate_effect = chain->add_effect(new ComplexModulateEffect(), multiply_effect, fft_input);
+ CHECK(modulate_effect->set_int("num_repeats_x", div_round_up(input_width, fft_width - pad_width)));
+ CHECK(modulate_effect->set_int("num_repeats_y", div_round_up(input_height, fft_height - pad_height)));
+ last_effect = modulate_effect;
+
+ // Finally, do IFFT.
+ if (best_x_before_y_ifft) {
+ last_effect = add_ifft_and_discard(chain, last_effect, fft_width, pad_width, FFTPassEffect::HORIZONTAL);
+ last_effect = add_ifft_and_discard(chain, last_effect, fft_height, pad_height, FFTPassEffect::VERTICAL);
+ } else {
+ last_effect = add_ifft_and_discard(chain, last_effect, fft_height, pad_height, FFTPassEffect::VERTICAL);
+ last_effect = add_ifft_and_discard(chain, last_effect, fft_width, pad_width, FFTPassEffect::HORIZONTAL);
+ }
+
+ // ...and crop away any extra padding we have have added.
+ last_effect = chain->add_effect(crop_effect);
+
+ chain->replace_sender(self, chain->find_node_for_effect(last_effect));
+ self->disabled = true;
+}
+
+} // namespace movit
--- /dev/null
+#ifndef _MOVIT_FFT_CONVOLUTION_EFFECT_H
+#define _MOVIT_FFT_CONVOLUTION_EFFECT_H 1
+
+// FFTConvolutionEffect applies an arbitrary 2D convolution between the input image
+// and a convolution kernel (assumed to be much smaller than the image).
+// It does this convolution using multiple smaller FFTs and an algorithm called
+// overlap-discard (also known as overlap-save) to achieve much higher
+// efficiency than direct evaluation of the convolution, at some expense of
+// accuracy.
+//
+// FFTConvolutionEffect follows the usual convention for convolution, which is that
+// you sample from the origin pixel, and then up and to the left from that. This means
+// that (in horizontal 1D) [1 0 0 0 0 ...] would be an identity transform, and that
+// [0 1 0 0 0 ...] would mean sampling one pixel to the left of the origin, which
+// effectively move would move the image one pixel to the right.
+//
+// The basic idea of the acceleration comes from the the convolution theorem
+// (which holds in any number of dimensions), namely that FFT(A ⊙ B) =
+// FFT(A) * FFT(B), where ⊙ is circular convolution and * is pointwise
+// multiplication. This means that A ⊙ B = IFFT(FFT(A) * FFT(B)), and since
+// we can do a 2D FFT in O(n² log n), this is asymptotically better than
+// direct convolution, which is O(n²m²) (where m is the size of the convolution
+// kernel). However, the convolution theorem is rarely _directly_ applicable,
+// for two reasons:
+//
+// - ⊙ is _circular_ convolution, which means that inputs are taken to
+// repeat (wrap around), which is rarely what you want.
+// - A and B must be the same size, which means that to convolve a 1280x720
+// kernel with a 64x64 kernel, you need to zero pad the 64x64 kernel and
+// then do _two_ full 1280x720 FFTs (one for each of A and B).
+//
+// The first problem is solved by adding m-1 zero pixels (horizontally
+// and vertically) as padding, and then discarding the result of those pixels.
+// This causes the output to be identical to a non-circular convolution.
+//
+// The second is slightly more tricky, and there are multiple ways of solving
+// it. The one that appears to be the most suitable to suitable for GPU use,
+// and the one that is used here, is overlap-discard (more commonly but less
+// precisely known as overlap-save). In overlap-discard, the input is broken
+// up into multiple equally-sized slices which are then FFTed and convolved
+// with the kernel individually. (The kernel must still be zero padded to the
+// same size as the slice, but this is typically much smaller then the full
+// picture.) As before, the pad area contains data that's essentially junk,
+// which is thrown away when the slices are put together again.
+//
+// The optimal slice size is a tradeoff. More slices means more space wasted
+// for padding, since the padding is the same no matter the slice size,
+// but fewer slices means we need to do larger FFTs (although fewer of them).
+// There's no exact closed formula for this, especially since the 2D case
+// makes things a bit more tricky with ordering of the X versus Y passes,
+// so we simply try all possible sizes and orderings, attempting to estimate
+// roughly how much each operation will cost. The result isn't perfect, though;
+// FFTW has a mode for actually measuring, which they claim improves speeds
+// by ~2x over simple estimation, but they also have much more freedom in
+// their execution model than we do.
+//
+// The output _size_ of a convolution can be defined in a couple of different
+// ways; in a sense, what's the most reasonable is using only the central part
+// of the result (the mode “valid” in MATLAB/Octave), since that is the only
+// one not used by any edge pixels. (FFTConvolutionEffect assumes normal Movit
+// edge pixel behavior, which is to repeat the outermost pixels.) You could also
+// keep all the output pixels (“full” in MATLAB/Octave), which is nicely symmetric.
+// However, for video processing, typically what you want is to have the _same_
+// output size as input size, so we crop to the input size. This means that
+// you'll get some of the edge-affected pixels but not all, but it's usually
+// an okay tradeoff.
+//
+// FFTConvolutionEffect does not do any actual pixel work by itself; it
+// rewrites itself into a long chain of SliceEffect, FFTPassEffect, FFTInput
+// and ComplexModulationEffect to do its bidding. Note that currently, due to
+// Movit limitations, we need to know the number of FFT passes at finalize()
+// time, which in turn means you cannot change image or kernel size on the fly.
+
+#include <assert.h>
+#include <epoxy/gl.h>
+#include <string>
+
+#include "effect.h"
+#include "fft_input.h"
+
+namespace movit {
+
+class PaddingEffect;
+
+class FFTConvolutionEffect : public Effect {
+public:
+ FFTConvolutionEffect(int input_width, int input_height, int convolve_width, int convolve_height);
+ ~FFTConvolutionEffect();
+ virtual std::string effect_type_id() const { return "FFTConvolutionEffect"; }
+ std::string output_fragment_shader() { assert(false); }
+ virtual void rewrite_graph(EffectChain *graph, Node *self);
+
+ // See FFTInput::set_pixel_data().
+ void set_convolution_kernel(const float *pixel_data)
+ {
+ assert(fft_input);
+ fft_input->set_pixel_data(pixel_data);
+ }
+
+private:
+ int input_width, input_height;
+ int convolve_width, convolve_height;
+
+ // Chosen by algorithm.
+ int fft_width, fft_height;
+
+ // Both of these are owned by us if owns_effects is true (before finalize()),
+ // and otherwise owned by the EffectChain.
+ FFTInput *fft_input;
+ PaddingEffect *crop_effect;
+ bool owns_effects;
+};
+
+} // namespace movit
+
+#endif // !defined(_MOVIT_FFT_CONVOLUTION_EFFECT_H)
--- /dev/null
+// Unit tests for FFTConvolutionEffect.
+
+#include <epoxy/gl.h>
+#include <math.h>
+
+#include "effect_chain.h"
+#include "gtest/gtest.h"
+#include "image_format.h"
+#include "test_util.h"
+#include "fft_convolution_effect.h"
+
+namespace movit {
+
+TEST(FFTConvolutionEffectTest, Identity) {
+ const int size = 4;
+
+ float data[size * size] = {
+ 0.1, 1.1, 2.1, 3.1,
+ 0.2, 1.2, 2.2, 3.2,
+ 0.3, 1.3, 2.3, 3.3,
+ 0.4, 1.4, 2.4, 3.4,
+ };
+ float out_data[size * size];
+
+ for (int convolve_size = 1; convolve_size < 10; ++convolve_size) {
+ float kernel[convolve_size * convolve_size];
+ for (int i = 0; i < convolve_size * convolve_size; ++i) {
+ kernel[i] = 0.0f;
+ }
+ kernel[0] = 1.0f;
+
+ EffectChainTester tester(NULL, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ tester.add_input(data, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR, size, size);
+
+ FFTConvolutionEffect *fft_effect = new FFTConvolutionEffect(size, size, convolve_size, convolve_size);
+ tester.get_chain()->add_effect(fft_effect);
+ fft_effect->set_convolution_kernel(kernel);
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR, OUTPUT_ALPHA_FORMAT_PREMULTIPLIED);
+
+ expect_equal(data, out_data, size, size, 0.02, 0.003);
+ }
+}
+
+TEST(FFTConvolutionEffectTest, Constant) {
+ const int size = 4, convolve_size = 17;
+ const float f = 7.0f;
+
+ float data[size * size] = {
+ 0.1, 1.1, 2.1, 3.1,
+ 0.2, 1.2, 2.2, 3.2,
+ 0.3, 1.3, 2.3, 3.3,
+ 0.4, 1.4, 2.4, 3.4,
+ };
+ float expected_data[size * size] = {
+ f * 0.1, f * 1.1, f * 2.1, f * 3.1,
+ f * 0.2, f * 1.2, f * 2.2, f * 3.2,
+ f * 0.3, f * 1.3, f * 2.3, f * 3.3,
+ f * 0.4, f * 1.4, f * 2.4, f * 3.4,
+ };
+ float out_data[size * size];
+ float kernel[convolve_size * convolve_size];
+ for (int i = 0; i < convolve_size * convolve_size; ++i) {
+ kernel[i] = 0.0f;
+ }
+ kernel[0] = f;
+
+ EffectChainTester tester(NULL, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ tester.add_input(data, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR, size, size);
+
+ FFTConvolutionEffect *fft_effect = new FFTConvolutionEffect(size, size, convolve_size, convolve_size);
+ tester.get_chain()->add_effect(fft_effect);
+ fft_effect->set_convolution_kernel(kernel);
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR, OUTPUT_ALPHA_FORMAT_PREMULTIPLIED);
+
+ // Somewhat looser bounds due to the higher magnitude.
+ expect_equal(expected_data, out_data, size, size, f * 0.03, f * 0.004);
+}
+
+TEST(FFTConvolutionEffectTest, MoveRight) {
+ const int size = 4, convolve_size = 3;
+
+ float data[size * size] = {
+ 0.1, 1.1, 2.1, 3.1,
+ 0.2, 1.2, 2.2, 3.2,
+ 0.3, 1.3, 2.3, 3.3,
+ 0.4, 1.4, 2.4, 3.4,
+ };
+ float kernel[convolve_size * convolve_size] = {
+ 0.0, 1.0, 0.0,
+ 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0,
+ };
+ float expected_data[size * size] = {
+ 0.1, 0.1, 1.1, 2.1,
+ 0.2, 0.2, 1.2, 2.2,
+ 0.3, 0.3, 1.3, 2.3,
+ 0.4, 0.4, 1.4, 2.4,
+ };
+ float out_data[size * size];
+
+ EffectChainTester tester(NULL, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ tester.add_input(data, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR, size, size);
+
+ FFTConvolutionEffect *fft_effect = new FFTConvolutionEffect(size, size, convolve_size, convolve_size);
+ tester.get_chain()->add_effect(fft_effect);
+ fft_effect->set_convolution_kernel(kernel);
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR, OUTPUT_ALPHA_FORMAT_PREMULTIPLIED);
+
+ expect_equal(expected_data, out_data, size, size, 0.02, 0.003);
+}
+
+TEST(FFTConvolutionEffectTest, MoveDown) {
+ const int size = 4, convolve_size = 3;
+
+ float data[size * size] = {
+ 0.1, 1.1, 2.1, 3.1,
+ 0.2, 1.2, 2.2, 3.2,
+ 0.3, 1.3, 2.3, 3.3,
+ 0.4, 1.4, 2.4, 3.4,
+ };
+ float kernel[convolve_size * convolve_size] = {
+ 0.0, 0.0, 0.0,
+ 1.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0,
+ };
+ float expected_data[size * size] = {
+ 0.1, 1.1, 2.1, 3.1,
+ 0.1, 1.1, 2.1, 3.1,
+ 0.2, 1.2, 2.2, 3.2,
+ 0.3, 1.3, 2.3, 3.3,
+ };
+ float out_data[size * size];
+
+ EffectChainTester tester(NULL, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ tester.add_input(data, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR, size, size);
+
+ FFTConvolutionEffect *fft_effect = new FFTConvolutionEffect(size, size, convolve_size, convolve_size);
+ tester.get_chain()->add_effect(fft_effect);
+ fft_effect->set_convolution_kernel(kernel);
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR, OUTPUT_ALPHA_FORMAT_PREMULTIPLIED);
+
+ expect_equal(expected_data, out_data, size, size, 0.02, 0.003);
+}
+
+TEST(FFTConvolutionEffectTest, MergeWithLeft) {
+ const int size = 4, convolve_size = 3;
+
+ float data[size * size] = {
+ 0.1, 1.1, 2.1, 3.1,
+ 0.2, 1.2, 2.2, 3.2,
+ 0.3, 1.3, 2.3, 3.3,
+ 0.4, 1.4, 2.4, 3.4,
+ };
+ float kernel[convolve_size * convolve_size] = {
+ 1.0, 1.0, 0.0,
+ 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0,
+ };
+ float expected_data[size * size] = {
+ 0.1 + 0.1, 0.1 + 1.1, 1.1 + 2.1, 2.1 + 3.1,
+ 0.2 + 0.2, 0.2 + 1.2, 1.2 + 2.2, 2.2 + 3.2,
+ 0.3 + 0.3, 0.3 + 1.3, 1.3 + 2.3, 2.3 + 3.3,
+ 0.4 + 0.4, 0.4 + 1.4, 1.4 + 2.4, 2.4 + 3.4,
+ };
+ float out_data[size * size];
+
+ EffectChainTester tester(NULL, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ tester.add_input(data, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR, size, size);
+
+ FFTConvolutionEffect *fft_effect = new FFTConvolutionEffect(size, size, convolve_size, convolve_size);
+ tester.get_chain()->add_effect(fft_effect);
+ fft_effect->set_convolution_kernel(kernel);
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR, OUTPUT_ALPHA_FORMAT_PREMULTIPLIED);
+
+ expect_equal(expected_data, out_data, size, size, 0.02, 0.003);
+}
+
+TEST(FFTConvolutionEffectTest, NegativeCoefficients) {
+ const int size = 4;
+ const int convolve_width = 3, convolve_height = 2;
+
+ float data[size * size] = {
+ 0.1, 1.1, 2.1, 3.1,
+ 0.2, 1.2, 2.2, 3.2,
+ 0.3, 1.3, 2.3, 3.3,
+ 0.4, 1.4, 2.4, 3.4,
+ };
+ float kernel[convolve_width * convolve_height] = {
+ 1.0, 0.0, 0.0,
+ 0.0, 0.0, -0.5,
+ };
+ float expected_data[size * size] = {
+ 0.1 - 0.5 * 0.1, 1.1 - 0.5 * 0.1, 2.1 - 0.5 * 0.1, 3.1 - 0.5 * 1.1,
+ 0.2 - 0.5 * 0.1, 1.2 - 0.5 * 0.1, 2.2 - 0.5 * 0.1, 3.2 - 0.5 * 1.1,
+ 0.3 - 0.5 * 0.2, 1.3 - 0.5 * 0.2, 2.3 - 0.5 * 0.2, 3.3 - 0.5 * 1.2,
+ 0.4 - 0.5 * 0.3, 1.4 - 0.5 * 0.3, 2.4 - 0.5 * 0.3, 3.4 - 0.5 * 1.3,
+ };
+ float out_data[size * size];
+
+ EffectChainTester tester(NULL, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ tester.add_input(data, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR, size, size);
+
+ FFTConvolutionEffect *fft_effect = new FFTConvolutionEffect(size, size, convolve_width, convolve_height);
+ tester.get_chain()->add_effect(fft_effect);
+ fft_effect->set_convolution_kernel(kernel);
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR, OUTPUT_ALPHA_FORMAT_PREMULTIPLIED);
+
+ expect_equal(expected_data, out_data, size, size, 0.02, 0.003);
+}
+
+} // namespace movit
--- /dev/null
+#include <string.h>
+#include <assert.h>
+#include <epoxy/gl.h>
+#include <fftw3.h>
+
+#include "effect_util.h"
+#include "fp16.h"
+#include "fft_input.h"
+#include "resource_pool.h"
+#include "util.h"
+
+using namespace std;
+
+namespace movit {
+
+FFTInput::FFTInput(unsigned width, unsigned height)
+ : texture_num(0),
+ fft_width(width),
+ fft_height(height),
+ convolve_width(width),
+ convolve_height(height),
+ pixel_data(NULL)
+{
+ register_int("fft_width", &fft_width);
+ register_int("fft_height", &fft_height);
+}
+
+FFTInput::~FFTInput()
+{
+ if (texture_num != 0) {
+ resource_pool->release_2d_texture(texture_num);
+ }
+}
+
+void FFTInput::set_gl_state(GLuint glsl_program_num, const string& prefix, unsigned *sampler_num)
+{
+ glActiveTexture(GL_TEXTURE0 + *sampler_num);
+ check_error();
+
+ if (texture_num == 0) {
+ assert(pixel_data != NULL);
+
+ // Do the FFT. Our FFTs should typically be small enough and
+ // the data changed often enough that FFTW_ESTIMATE should be
+ // quite OK. Otherwise, we'd need to worry about caching these
+ // plans (possibly including FFTW wisdom).
+ fftw_complex *in = (fftw_complex *)fftw_malloc(sizeof(fftw_complex) * fft_width * fft_height);
+ fftw_complex *out = (fftw_complex *)fftw_malloc(sizeof(fftw_complex) * fft_width * fft_height);
+ fftw_plan p = fftw_plan_dft_2d(fft_height, fft_width, in, out, FFTW_FORWARD, FFTW_ESTIMATE);
+
+ // Zero pad.
+ for (int i = 0; i < fft_height * fft_width; ++i) {
+ in[i][0] = 0.0;
+ in[i][1] = 0.0;
+ }
+ for (unsigned y = 0; y < convolve_height; ++y) {
+ for (unsigned x = 0; x < convolve_width; ++x) {
+ int i = y * fft_width + x;
+ in[i][0] = pixel_data[y * convolve_width + x];
+ in[i][1] = 0.0;
+ }
+ }
+
+ fftw_execute(p);
+
+ // Convert to fp16.
+ fp16_int_t *kernel = new fp16_int_t[fft_width * fft_height * 2];
+ for (int i = 0; i < fft_width * fft_height; ++i) {
+ kernel[i * 2 + 0] = fp64_to_fp16(out[i][0]);
+ kernel[i * 2 + 1] = fp64_to_fp16(out[i][1]);
+ }
+
+ // (Re-)upload the texture.
+ texture_num = resource_pool->create_2d_texture(GL_RG16F, fft_width, fft_height);
+ glBindTexture(GL_TEXTURE_2D, texture_num);
+ check_error();
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+ check_error();
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+ check_error();
+ glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ check_error();
+ glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, fft_width, fft_height, GL_RG, GL_HALF_FLOAT, kernel);
+ check_error();
+ glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
+ check_error();
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+ check_error();
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+ check_error();
+
+ fftw_free(in);
+ fftw_free(out);
+ delete[] kernel;
+ } else {
+ glBindTexture(GL_TEXTURE_2D, texture_num);
+ check_error();
+ }
+
+ // Bind it to a sampler.
+ set_uniform_int(glsl_program_num, prefix, "tex", *sampler_num);
+ ++*sampler_num;
+}
+
+string FFTInput::output_fragment_shader()
+{
+ return read_file("flat_input.frag");
+}
+
+void FFTInput::invalidate_pixel_data()
+{
+ if (texture_num != 0) {
+ resource_pool->release_2d_texture(texture_num);
+ texture_num = 0;
+ }
+}
+
+bool FFTInput::set_int(const std::string& key, int value)
+{
+ if (key == "needs_mipmaps") {
+ // We cannot supply mipmaps; it would not make any sense for FFT data.
+ return (value == 0);
+ }
+ if (key == "fft_width") {
+ if (value < int(convolve_width)) {
+ return false;
+ }
+ invalidate_pixel_data();
+ }
+ if (key == "fft_height") {
+ if (value < int(convolve_height)) {
+ return false;
+ }
+ invalidate_pixel_data();
+ }
+ return Effect::set_int(key, value);
+}
+
+} // namespace movit
--- /dev/null
+#ifndef _MOVIT_FFT_INPUT_H
+#define _MOVIT_FFT_INPUT_H 1
+
+// FFTInput is used by FFTConvolutionEffect to send in the FFTed version of a
+// mostly static, one-channel data set, typically the convolution kernel
+// with some zero padding.
+//
+// Since the kernel is typically small and unlikely to change often,
+// it will be faster to FFT it once on the CPU (using the excellent FFTW3
+// library) and keep it in a texture, rather than FFT-ing it over and over on
+// the GPU. (We do not currently support caching Movit intermediates between
+// frames.) As an extra bonus, we can then do it in double precision and round
+// precisely to fp16 afterwards.
+//
+// This class is tested as part of by FFTConvolutionEffectTest.
+
+#include <epoxy/gl.h>
+#include <assert.h>
+#include <string>
+
+#include "effect.h"
+#include "effect_chain.h"
+#include "image_format.h"
+#include "input.h"
+
+namespace movit {
+
+class ResourcePool;
+
+class FFTInput : public Input {
+public:
+ FFTInput(unsigned width, unsigned height);
+ ~FFTInput();
+
+ virtual std::string effect_type_id() const { return "FFTInput"; }
+ std::string output_fragment_shader();
+
+ // FFTs the data and uploads the texture if it has changed since last time.
+ void set_gl_state(GLuint glsl_program_num, const std::string& prefix, unsigned *sampler_num);
+
+ unsigned get_width() const { return fft_width; }
+ unsigned get_height() const { return fft_height; }
+
+ // Strictly speaking, FFT data doesn't have any colorspace or gamma;
+ // these values are the Movit standards for “do nothing”.
+ Colorspace get_color_space() const { return COLORSPACE_sRGB; }
+ GammaCurve get_gamma_curve() const { return GAMMA_LINEAR; }
+ virtual AlphaHandling alpha_handling() const { return INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA; }
+ virtual bool is_single_texture() const { return true; }
+ virtual bool can_output_linear_gamma() const { return true; }
+
+ // Tells the input where to fetch the actual pixel data. Note that if you change
+ // this data, you must either call set_pixel_data() again (using the same pointer
+ // is fine), or invalidate_pixel_data(). Otherwise, the FFT won't be recalculated,
+ // and the texture won't be re-uploaded on subsequent frames.
+ void set_pixel_data(const float *pixel_data)
+ {
+ this->pixel_data = pixel_data;
+ invalidate_pixel_data();
+ }
+
+ void invalidate_pixel_data();
+
+ virtual void inform_added(EffectChain *chain)
+ {
+ resource_pool = chain->get_resource_pool();
+ }
+
+ virtual bool set_int(const std::string& key, int value);
+
+private:
+ GLuint texture_num;
+ int fft_width, fft_height;
+ unsigned convolve_width, convolve_height;
+ const float *pixel_data;
+ ResourcePool *resource_pool;
+};
+
+} // namespace movit
+
+#endif // !defined(_MOVIT_FFT_INPUT_H)
namespace movit {
SliceEffect::SliceEffect()
+ : input_slice_size(1),
+ output_slice_size(1),
+ offset(0),
+ direction(VERTICAL)
{
register_int("input_slice_size", &input_slice_size);
register_int("output_slice_size", &output_slice_size);
+ register_int("offset", &offset);
register_int("direction", (int *)&direction);
}
set_uniform_float(glsl_program_num, prefix, "output_coord_to_slice_num", float(output_width) / float(output_slice_size));
set_uniform_float(glsl_program_num, prefix, "slice_num_to_input_coord", float(input_slice_size) / float(input_width));
set_uniform_float(glsl_program_num, prefix, "slice_offset_to_input_coord", float(output_slice_size) / float(input_width));
+ set_uniform_float(glsl_program_num, prefix, "offset", float(offset) / float(input_width));
} else {
set_uniform_float(glsl_program_num, prefix, "output_coord_to_slice_num", float(output_height) / float(output_slice_size));
set_uniform_float(glsl_program_num, prefix, "slice_num_to_input_coord", float(input_slice_size) / float(input_height));
set_uniform_float(glsl_program_num, prefix, "slice_offset_to_input_coord", float(output_slice_size) / float(input_height));
+ set_uniform_float(glsl_program_num, prefix, "offset", float(offset) / float(input_height));
}
// Normalized coordinates could potentially cause blurring of the image.
uniform float PREFIX(output_coord_to_slice_num);
uniform float PREFIX(slice_num_to_input_coord);
uniform float PREFIX(slice_offset_to_input_coord);
+uniform float PREFIX(offset);
vec4 FUNCNAME(vec2 tc) {
// DIRECTION_VERTICAL will be #defined to 1 if we are expanding vertically,
// and 0 otherwise.
#if DIRECTION_VERTICAL
- float sliced_coord = tc.y;
+ float sliced_coord = 1.0 - tc.y;
#else
float sliced_coord = tc.x;
#endif
float slice_offset = fract(sliced_coord * PREFIX(output_coord_to_slice_num));
// Find out where this slice begins in the input data, and then offset from that.
- float input_coord = slice_num * PREFIX(slice_num_to_input_coord) + slice_offset * PREFIX(slice_offset_to_input_coord);
+ float input_coord = slice_num * PREFIX(slice_num_to_input_coord) + slice_offset * PREFIX(slice_offset_to_input_coord) + PREFIX(offset);
#if DIRECTION_VERTICAL
- return INPUT(vec2(tc.x, input_coord));
+ return INPUT(vec2(tc.x, 1.0 - input_coord));
#else
return INPUT(vec2(input_coord, tc.y));
#endif
// discard roles, where one does convolutions by means of many small FFTs, but
// could also work as a (relatively boring) video effect on its own.
//
-// Note that vertical slices happen from the bottom, not the top, due to the
-// OpenGL coordinate system.
+// Note that vertical slices happen from the top, consistent with the rest of
+// Movit.
#include <epoxy/gl.h>
#include <string>
EffectChain *chain;
int input_width, input_height;
int input_slice_size, output_slice_size;
+ int offset;
Direction direction;
};
expect_equal(expected_data, out_data, 4, 2);
}
-TEST(SliceEffectTest, VerticalOverlapSlicesFromBottom) {
+TEST(SliceEffectTest, HorizontalOverlapWithOffset) {
+ float data[5 * 2] = {
+ /* 0.0f, */ 0.0f, 0.1f, 0.2f, 0.3f, 0.4f,
+ /* 0.4f, */ 0.4f, 0.3f, 0.2f, 0.1f, 0.0f,
+ };
+ float expected_data[9 * 2] = {
+ 0.0f, 0.0f, 0.1f, 0.1f, 0.2f, 0.3f, 0.3f, 0.4f, 0.4f,
+ 0.4f, 0.4f, 0.3f, 0.3f, 0.2f, 0.1f, 0.1f, 0.0f, 0.0f,
+ };
+ float out_data[9 * 2];
+
+ EffectChainTester tester(NULL, 9, 2, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ tester.add_input(data, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR, 5, 2);
+
+ Effect *slice_effect = tester.get_chain()->add_effect(new SliceEffect());
+ ASSERT_TRUE(slice_effect->set_int("input_slice_size", 2));
+ ASSERT_TRUE(slice_effect->set_int("output_slice_size", 3));
+ ASSERT_TRUE(slice_effect->set_int("offset", -1));
+ ASSERT_TRUE(slice_effect->set_int("direction", SliceEffect::HORIZONTAL));
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+ expect_equal(expected_data, out_data, 9, 2);
+}
+
+TEST(SliceEffectTest, VerticalOverlapSlicesFromTop) {
float data[2 * 3] = {
0.0f, 0.1f,
-
0.4f, 0.3f,
+
0.6f, 0.2f,
};
float expected_data[2 * 6] = {
0.0f, 0.1f,
- 0.0f, 0.1f,
- 0.0f, 0.1f,
+ 0.4f, 0.3f,
+ 0.6f, 0.2f,
+ 0.6f, 0.2f,
+ 0.6f, 0.2f,
+ 0.6f, 0.2f,
+ };
+ float out_data[2 * 6];
+
+ EffectChainTester tester(NULL, 2, 6, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ tester.add_input(data, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR, 2, 3);
+
+ Effect *slice_effect = tester.get_chain()->add_effect(new SliceEffect());
+ ASSERT_TRUE(slice_effect->set_int("input_slice_size", 2));
+ ASSERT_TRUE(slice_effect->set_int("output_slice_size", 3));
+ ASSERT_TRUE(slice_effect->set_int("direction", SliceEffect::VERTICAL));
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+ expect_equal(expected_data, out_data, 2, 6);
+}
+
+TEST(SliceEffectTest, VerticalOverlapOffsetsFromTop) {
+ float data[2 * 3] = {
0.0f, 0.1f,
0.4f, 0.3f,
+
+ 0.6f, 0.2f,
+ };
+ float expected_data[2 * 6] = {
+ 0.4f, 0.3f,
+ 0.6f, 0.2f,
+ 0.6f, 0.2f,
+
+ 0.6f, 0.2f,
+ 0.6f, 0.2f,
0.6f, 0.2f,
};
float out_data[2 * 6];
Effect *slice_effect = tester.get_chain()->add_effect(new SliceEffect());
ASSERT_TRUE(slice_effect->set_int("input_slice_size", 2));
ASSERT_TRUE(slice_effect->set_int("output_slice_size", 3));
+ ASSERT_TRUE(slice_effect->set_int("offset", 1));
ASSERT_TRUE(slice_effect->set_int("direction", SliceEffect::VERTICAL));
tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
return (a + b - 1) / b;
}
+// Algorithm from http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2.
+unsigned next_power_of_two(unsigned v)
+{
+ v--;
+ v |= v >> 1;
+ v |= v >> 2;
+ v |= v >> 4;
+ v |= v >> 8;
+ v |= v >> 16;
+ v++;
+ return v;
+}
+
} // namespace movit
// Clean up after fill_vertex_attribute().
void cleanup_vertex_attribute(GLuint glsl_program_num, const std::string &attribute_name, GLuint vbo);
+// If v is not already a power of two, return the first higher power of two.
+unsigned next_power_of_two(unsigned v);
+
} // namespace movit
#ifdef NDEBUG
projects / movit / commitdiff