X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=resample_effect.cpp;h=54eec864fe7a6c272fa68e3476dfcdf52b31c8a7;hp=f4808c4560437288a327156f10a2f0e794e1f991;hb=535fc8a0df75648968fd42c2f1ce8b150f5c2c13;hpb=c62391987241f1482a99b6f6417fbec1d0ef2344 diff --git a/resample_effect.cpp b/resample_effect.cpp index f4808c4..54eec86 100644 --- a/resample_effect.cpp +++ b/resample_effect.cpp @@ -7,6 +7,9 @@ #include #include #include +#include +#include +#include #include "effect_chain.h" #include "effect_util.h" @@ -15,6 +18,7 @@ #include "resample_effect.h" #include "util.h" +using namespace Eigen; using namespace std; namespace movit { @@ -59,7 +63,22 @@ unsigned gcd(unsigned a, unsigned b) template unsigned combine_samples(const Tap *src, Tap *dst, unsigned src_size, unsigned num_src_samples, unsigned max_samples_saved) { + // Cut off near-zero values at both sides. unsigned num_samples_saved = 0; + while (num_samples_saved < max_samples_saved && + num_src_samples > 0 && + fabs(src[0].weight) < 1e-6) { + ++src; + --num_src_samples; + ++num_samples_saved; + } + while (num_samples_saved < max_samples_saved && + num_src_samples > 0 && + fabs(src[num_src_samples - 1].weight) < 1e-6) { + --num_src_samples; + ++num_samples_saved; + } + for (unsigned i = 0, j = 0; i < num_src_samples; ++i, ++j) { // Copy the sample directly; it will be overwritten later if we can combine. if (dst != NULL) { @@ -113,6 +132,22 @@ unsigned combine_samples(const Tap *src, Tap *dst, unsigned sr return num_samples_saved; } +// 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. +template +void normalize_sum(Tap* vals, unsigned num) +{ + for (int normalize_pass = 0; normalize_pass < 2; ++normalize_pass) { + double sum = 0.0; + for (unsigned i = 0; i < num; ++i) { + sum += to_fp64(vals[i].weight); + } + for (unsigned i = 0; i < num; ++i) { + vals[i].weight = from_fp64(to_fp64(vals[i].weight) / sum); + } + } +} + // Make use of the bilinear filtering in the GPU to reduce the number of samples // we need to make. This is a bit more complex than BlurEffect since we cannot combine // two neighboring samples if their weights have differing signs, so we first need to @@ -141,19 +176,7 @@ unsigned combine_many_samples(const Tap *weights, unsigned src_size, unsi src_samples, src_samples - src_bilinear_samples); assert(int(src_samples) - int(num_samples_saved) == src_bilinear_samples); - - // 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) { - double sum = 0.0; - for (int i = 0; i < src_bilinear_samples; ++i) { - sum += to_fp64(bilinear_weights_ptr[i].weight); - } - for (int i = 0; i < src_bilinear_samples; ++i) { - bilinear_weights_ptr[i].weight = from_fp64( - to_fp64(bilinear_weights_ptr[i].weight) / sum); - } - } + normalize_sum(bilinear_weights_ptr, src_bilinear_samples); } return src_bilinear_samples; } @@ -175,7 +198,7 @@ double compute_sum_sq_error(const Tap* weights, unsigned num_weights, int lower_pos = int(floor(to_fp64(bilinear_weights[0].pos) * size - 0.5)); int upper_pos = int(ceil(to_fp64(bilinear_weights[num_bilinear_weights - 1].pos) * size - 0.5)) + 2; lower_pos = min(lower_pos, lrintf(weights[0].pos * size - 0.5)); - upper_pos = max(upper_pos, lrintf(weights[num_weights - 1].pos * size - 0.5)); + upper_pos = max(upper_pos, lrintf(weights[num_weights - 1].pos * size - 0.5) + 1); float* effective_weights = new float[upper_pos - lower_pos]; for (int i = 0; i < upper_pos - lower_pos; ++i) { @@ -502,6 +525,9 @@ void SingleResamplePassEffect::update_texture(GLuint glsl_program_num, const str // Now make use of the bilinear filtering in the GPU to reduce the number of samples // we need to make. Try fp16 first; if it's not accurate enough, we go to fp32. + // Our tolerance level for total error is a bit higher than the one for invididual + // samples, since one would assume overall errors in the shape don't matter as much. + const float max_error = 2.0f / (255.0f * 255.0f); Tap *bilinear_weights_fp16; src_bilinear_samples = combine_many_samples(weights, src_size, src_samples, dst_samples, &bilinear_weights_fp16); Tap *bilinear_weights_fp32 = NULL; @@ -513,11 +539,12 @@ void SingleResamplePassEffect::update_texture(GLuint glsl_program_num, const str bilinear_weights_fp16 + y * src_bilinear_samples, src_bilinear_samples, src_size); max_sum_sq_error_fp16 = std::max(max_sum_sq_error_fp16, sum_sq_error_fp16); + if (max_sum_sq_error_fp16 > max_error) { + break; + } } - // Our tolerance level for total error is a bit higher than the one for invididual - // samples, since one would assume overall errors in the shape don't matter as much. - if (max_sum_sq_error_fp16 > 2.0f / (255.0f * 255.0f)) { + if (max_sum_sq_error_fp16 > max_error) { fallback_to_fp32 = true; src_bilinear_samples = combine_many_samples(weights, src_size, src_samples, dst_samples, &bilinear_weights_fp32); }