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Fixed downscaling metric

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This commit is contained in:
Joshua Moerman 2014-08-19 10:26:41 +02:00
parent 224b7bfc0b
commit dd6e1abb49
4 changed files with 44 additions and 10 deletions
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38
lib/fingerprints/downscale.cpp
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@ -1,11 +1,39 @@
#include "downscale.hpp"
#include <image_io.hpp>
#include <algorithm>
downscale downscale::pre_calculate(const av::frame& frame){
// ffmpeg doesnt let us downscale all the way to 5 at once :(
auto const image = to_raw_rgb_image(frame, 5, 5);
extern "C" {
#include <libavutil/frame.h>
#include <libswscale/swscale.h>
}
#include <algorithm>
#include <iostream>
static raw_rgb_image downscale_step(AVFrame const * frame, int factor) {
raw_rgb_image image(frame->width / factor, frame->height / factor);
auto context = sws_getContext(frame->width, frame->height, static_cast<AVPixelFormat>(frame->format), image.width(), image.height(), image.format(), 0, nullptr, nullptr, nullptr);
if(!context) throw std::runtime_error("boem sws context");
sws_scale (context, {frame->data}, {frame->linesize}, 0, frame->height, {image.frame->data}, {image.frame->linesize});
sws_freeContext(context);
return image;
}
static raw_rgb_image downscale_to(const av::frame &frame, int w, int h){
// ffmpeg doesnt let us downscale all the way to 5 at once :(, so we do a loop
raw_rgb_image image;
auto new_frame = frame.get();
while(new_frame->width > 8*w && new_frame->height > 8*h){
image = downscale_step(new_frame, 4);
new_frame = image.frame.get();
}
return to_raw_rgb_image(image.frame, w, h);
}
downscale downscale::pre_calculate(av::frame const & frame){
auto const image = downscale_to(crop_to_square(frame), 5, 5);
downscale ret;
ret.data.assign(image.data.size(), 0);
@ -19,7 +47,7 @@ downscale downscale::calculate(const av::frame& frame){
return pre_calculate(frame);
}
double square(double x){
static double square(double x){
return x*x;
}

5
lib/image_io.cpp
View file

@ -15,6 +15,11 @@ extern "C" {
#include <cassert>
raw_rgb_image::raw_rgb_image()
: data()
, frame(nullptr, [](auto x){ av_frame_free(&x); })
{}
raw_rgb_image::raw_rgb_image(int W, int H)
: data(make_u(avpicture_get_size(AV_PIX_FMT_RGB24, W, H)))
, frame(av::frame_alloc())

1
lib/image_io.hpp
View file

@ -13,6 +13,7 @@ struct raw_rgb_image {
std::vector<uint8_t, av::allocator<uint8_t>> data;
av::frame frame;
raw_rgb_image();
raw_rgb_image(int W, int H);
int width() const;

10
src/main.cpp
View file

@ -28,10 +28,10 @@ using namespace std;
namespace fs = boost::filesystem;
namespace ar = boost::archive;
using Database = image_database<rgb_wavelet_coefficients>;
using Database = image_database<downscale>;
using Mozaic = map<pair<int, int>, string>;
Database read_database(string const & database_directory){
static Database read_database(string const & database_directory){
Database db;
auto const database_file = database_directory + ".db";
@ -60,10 +60,10 @@ Database read_database(string const & database_directory){
return db;
}
Mozaic create_mozaic(Database const & db, string const & filename, int h_tiles, int v_tiles){
static Mozaic create_mozaic(Database const & db, string const & filename, int h_tiles, int v_tiles){
Mozaic mozaic;
apply_to_tiles("image.jpg", h_tiles, v_tiles, [&](int c, int r, av::frame const & frame){
apply_to_tiles(filename, h_tiles, v_tiles, [&](int c, int r, av::frame const & frame){
auto const index = db.nearest_image(frame);
cout << colors::red("tile ") << c << ", " << r << ": " << db.filename(index) << endl;
mozaic[make_pair(c, r)] = db.filename(index);
@ -72,7 +72,7 @@ Mozaic create_mozaic(Database const & db, string const & filename, int h_tiles,
return mozaic;
}
void save_mozaic(Mozaic const & mozaic, string filename, int h_tiles, int v_tiles){
static void save_mozaic(Mozaic const & mozaic, string filename, int h_tiles, int v_tiles){
auto const pix_fmt = AV_PIX_FMT_YUVJ444P;
auto const codec_id= AV_CODEC_ID_MJPEG;