X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;ds=sidebyside;f=resample_effect.cpp;h=2a6aecf87e8e01aebbba501a857ac73e6e61d57e;hb=d8b01c80815f74603eddd2b8f66249a967fa7bab;hp=74b059404332cbab2da91d7e403954997df96a9d;hpb=8ea03db1932e4a76f457e0ecdfe31a4c8be0e0eb;p=movit

diff --git a/resample_effect.cpp b/resample_effect.cpp
index 74b0594..2a6aecf 100644
--- a/resample_effect.cpp
+++ b/resample_effect.cpp
@@ -10,6 +10,7 @@
 
 #include "effect_chain.h"
 #include "effect_util.h"
+#include "fp16.h"
 #include "resample_effect.h"
 #include "util.h"
 
@@ -142,7 +143,7 @@ void ResampleEffect::inform_input_size(unsigned input_num, unsigned width, unsig
 	input_height = height;
 	update_size();
 }
-		
+
 void ResampleEffect::update_size()
 {
 	bool ok = true;
@@ -170,6 +171,13 @@ bool ResampleEffect::set_float(const string &key, float value) {
 		update_size();
 		return true;
 	}
+	if (key == "top") {
+		// Compensate for the bottom-left origin.
+		return vpass->set_float("offset", -value);
+	}
+	if (key == "left") {
+		return hpass->set_float("offset", value);
+	}
 	return false;
 }
 
@@ -178,16 +186,19 @@ SingleResamplePassEffect::SingleResamplePassEffect(ResampleEffect *parent)
 	  direction(HORIZONTAL),
  	  input_width(1280),
  	  input_height(720),
+	  offset(0.0),
 	  last_input_width(-1),
 	  last_input_height(-1),
 	  last_output_width(-1),
-	  last_output_height(-1)
+	  last_output_height(-1),
+	  last_offset(0.0 / 0.0)  // NaN.
 {
 	register_int("direction", (int *)&direction);
 	register_int("input_width", &input_width);
 	register_int("input_height", &input_height);
 	register_int("output_width", &output_width);
 	register_int("output_height", &output_height);
+	register_float("offset", &offset);
 
 	glGenTextures(1, &texnum);
 }
@@ -293,6 +304,8 @@ void SingleResamplePassEffect::update_texture(GLuint glsl_program_num, const str
 	int int_radius = lrintf(LANCZOS_RADIUS / radius_scaling_factor);
 	int src_samples = int_radius * 2 + 1;
 	float *weights = new float[dst_samples * src_samples * 2];
+	float subpixel_offset = offset - lrintf(offset);  // The part not covered by whole_pixel_offset.
+	assert(subpixel_offset >= -0.5f && subpixel_offset <= 0.5f);
 	for (unsigned y = 0; y < dst_samples; ++y) {
 		// Find the point around which we want to sample the source image,
 		// compensating for differing pixel centers as the scale changes.
@@ -302,11 +315,10 @@ void SingleResamplePassEffect::update_texture(GLuint glsl_program_num, const str
 		// Now sample <int_radius> pixels on each side around that point.
 		for (int i = 0; i < src_samples; ++i) {
 			int src_y = base_src_y + i - int_radius;
-			float weight = lanczos_weight(radius_scaling_factor * (src_y - center_src_y), LANCZOS_RADIUS);
+			float weight = lanczos_weight(radius_scaling_factor * (src_y - center_src_y - subpixel_offset), LANCZOS_RADIUS);
 			weights[(y * src_samples + i) * 2 + 0] = weight * radius_scaling_factor;
 			weights[(y * src_samples + i) * 2 + 1] = (src_y + 0.5) / float(src_size);
 		}
-
 	}
 
 	// Now make use of the bilinear filtering in the GPU to reduce the number of samples
@@ -325,26 +337,36 @@ void SingleResamplePassEffect::update_texture(GLuint glsl_program_num, const str
 
 	// Now that we know the right width, actually combine the samples.
 	float *bilinear_weights = new float[dst_samples * src_bilinear_samples * 2];
+	fp16_int_t *bilinear_weights_fp16 = new fp16_int_t[dst_samples * src_bilinear_samples * 2];
 	for (unsigned y = 0; y < dst_samples; ++y) {
+		float *bilinear_weights_ptr = bilinear_weights + (y * src_bilinear_samples) * 2;
+		fp16_int_t *bilinear_weights_fp16_ptr = bilinear_weights_fp16 + (y * src_bilinear_samples) * 2;
 		unsigned num_samples_saved = combine_samples(
 			weights + (y * src_samples) * 2,
-			bilinear_weights + (y * src_bilinear_samples) * 2,
+			bilinear_weights_ptr,
 			src_samples,
 			src_samples - src_bilinear_samples);
 		assert(int(src_samples) - int(num_samples_saved) == src_bilinear_samples);
 
+		// Convert to fp16.
+		for (int i = 0; i < src_bilinear_samples; ++i) {
+			bilinear_weights_fp16_ptr[i * 2 + 0] = fp64_to_fp16(bilinear_weights_ptr[i * 2 + 0]);
+			bilinear_weights_fp16_ptr[i * 2 + 1] = fp64_to_fp16(bilinear_weights_ptr[i * 2 + 1]);
+		}
+
 		// Normalize so that the sum becomes one. Note that we do it twice;
 		// this sometimes helps a tiny little bit when we have many samples.
 		for (int normalize_pass = 0; normalize_pass < 2; ++normalize_pass) {
-			float sum = 0.0;
+			double sum = 0.0;
 			for (int i = 0; i < src_bilinear_samples; ++i) {
-				sum += bilinear_weights[(y * src_bilinear_samples + i) * 2 + 0];
+				sum += fp16_to_fp64(bilinear_weights_fp16_ptr[i * 2 + 0]);
 			}
 			for (int i = 0; i < src_bilinear_samples; ++i) {
-				bilinear_weights[(y * src_bilinear_samples + i) * 2 + 0] /= sum;
+				bilinear_weights_fp16_ptr[i * 2 + 0] = fp64_to_fp16(
+					fp16_to_fp64(bilinear_weights_fp16_ptr[i * 2 + 0]) / sum);
 			}
 		}
-	}	
+	}
 
 	// Encode as a two-component texture. Note the GL_REPEAT.
 	glActiveTexture(GL_TEXTURE0 + *sampler_num);
@@ -357,11 +379,12 @@ void SingleResamplePassEffect::update_texture(GLuint glsl_program_num, const str
 	check_error();
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 	check_error();
-	glTexImage2D(GL_TEXTURE_2D, 0, GL_RG16F, src_bilinear_samples, dst_samples, 0, GL_RG, GL_FLOAT, bilinear_weights);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RG16F, src_bilinear_samples, dst_samples, 0, GL_RG, GL_HALF_FLOAT, bilinear_weights_fp16);
 	check_error();
 
 	delete[] weights;
 	delete[] bilinear_weights;
+	delete[] bilinear_weights_fp16;
 }
 
 void SingleResamplePassEffect::set_gl_state(GLuint glsl_program_num, const string &prefix, unsigned *sampler_num)
@@ -376,12 +399,14 @@ void SingleResamplePassEffect::set_gl_state(GLuint glsl_program_num, const strin
 	if (input_width != last_input_width ||
 	    input_height != last_input_height ||
 	    output_width != last_output_width ||
-	    output_height != last_output_height) {
+	    output_height != last_output_height ||
+	    offset != last_offset) {
 		update_texture(glsl_program_num, prefix, sampler_num);
 		last_input_width = input_width;
 		last_input_height = input_height;
 		last_output_width = output_width;
 		last_output_height = output_height;
+		last_offset = offset;
 	}
 
 	glActiveTexture(GL_TEXTURE0 + *sampler_num);
@@ -399,9 +424,18 @@ void SingleResamplePassEffect::set_gl_state(GLuint glsl_program_num, const strin
 	set_uniform_float(glsl_program_num, prefix, "sample_x_scale", 1.0f / src_bilinear_samples);
 	set_uniform_float(glsl_program_num, prefix, "sample_x_offset", 0.5f / src_bilinear_samples);
 
+	float whole_pixel_offset;
+	if (direction == SingleResamplePassEffect::VERTICAL) {
+		whole_pixel_offset = lrintf(offset) / float(input_height);
+	} else {
+		whole_pixel_offset = lrintf(offset) / float(input_width);
+	}
+	set_uniform_float(glsl_program_num, prefix, "whole_pixel_offset", whole_pixel_offset);
+
 	// We specifically do not want mipmaps on the input texture;
 	// they break minification.
-	glActiveTexture(GL_TEXTURE0);
+	Node *self = chain->find_node_for_effect(this);
+	glActiveTexture(chain->get_input_sampler(self, 0));
 	check_error();
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 	check_error();