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Adds possibility to do asymmetric fingerprint comparison

Adds another metric (doesn't work yet)
Adds more constness
master
Joshua Moerman 10 years ago
parent
commit
224b7bfc0b
  1. 4
      lib/CMakeLists.txt
  2. 2
      lib/av.hpp
  3. 16
      lib/fingerprint_traits.hpp
  4. 4
      lib/fingerprints.hpp
  5. 35
      lib/fingerprints/downscale.cpp
  6. 27
      lib/fingerprints/downscale.hpp
  7. 77
      lib/fingerprints/wavelet.cpp
  8. 22
      lib/fingerprints/wavelet.hpp
  9. 2
      lib/image_database.cpp
  10. 16
      lib/image_database.hpp
  11. 63
      lib/image_io.cpp
  12. 6
      lib/image_io.hpp
  13. 3
      src/compress.cpp
  14. 10
      src/fingerprint_test.cpp
  15. 51
      src/main.cpp
  16. 14
      src/needle.cpp
  17. 58
      src/writer.cpp

4
lib/CMakeLists.txt

@ -1,6 +1,6 @@
file(GLOB sources "*.cpp")
file(GLOB headers "*.hpp")
file(GLOB_RECURSE sources "*.cpp")
file(GLOB_RECURSE headers "*.hpp")
set(libs avformat avcodec avutil swscale)

2
lib/av.hpp

@ -44,7 +44,7 @@ namespace av {
// AVFrame related
using frame = std::unique_ptr<AVFrame, deleter<AVFrame>>;
frame frame_alloc();
frame frame_clone(frame const & f);
frame frame_clone(frame const & f); // creates a clone with the *same* buffer
AVPixelFormat get_format(frame const & f);
// Allocator

16
lib/fingerprint_traits.hpp

@ -0,0 +1,16 @@
#pragma once
#include"av.hpp"
#include <utility>
// A fingerprint is used to speed up comparison. However, this is done assymetrically. Only the
// compressed version is used in the database, but for comparison the full image can be used.
template <typename Fingerprint>
struct fingerprint_traits {
using fingerprint = Fingerprint;
using pre_fingerprint = decltype(fingerprint::pre_calculate(std::declval<av::frame>()));
static pre_fingerprint pre_calculate(av::frame const & frame) { return fingerprint::pre_calculate(frame); }
static fingerprint calculate(av::frame const & frame) { return fingerprint::calculate(frame); }
static auto distance(fingerprint const & x, pre_fingerprint const & y) { return x.distance_to(y); }
};

4
lib/fingerprints.hpp

@ -0,0 +1,4 @@
#pragma once
#include "fingerprints/wavelet.hpp"
#include "fingerprints/downscale.hpp"

35
lib/fingerprints/downscale.cpp

@ -0,0 +1,35 @@
#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);
downscale ret;
ret.data.assign(image.data.size(), 0);
std::copy(image.data.begin(), image.data.end(), ret.data.begin());
return ret;
}
downscale downscale::calculate(const av::frame& frame){
return pre_calculate(frame);
}
double square(double x){
return x*x;
}
double downscale::distance_to(const downscale& fingerprint) const {
assert(data.size() == fingerprint.data.size());
double distance = 0;
for(size_t i = 0; i < data.size(); ++i){
distance += square(data[i] - fingerprint.data[i]);
}
return distance;
}

27
lib/fingerprints/downscale.hpp

@ -0,0 +1,27 @@
#pragma once
#include <av.hpp>
#include <fingerprint_traits.hpp>
#include <boost/serialization/access.hpp>
#include <boost/serialization/vector.hpp>
#include <iosfwd>
#include <vector>
struct downscale {
std::vector<uint8_t> data;
static downscale pre_calculate(av::frame const & frame);
static downscale calculate(av::frame const & frame);
double distance_to(downscale const & fingerprint) const;
private:
friend class boost::serialization::access;
template<class Archive>
void serialize(Archive & ar, const unsigned int /*version*/){
ar & data;
}
};
std::ostream& operator<<(std::ostream& out, downscale const & x);

77
lib/fingerprint.cpp → lib/fingerprints/wavelet.cpp

@ -1,14 +1,37 @@
#include "fingerprint.hpp"
#include "wavelet.hpp"
#include "utilities.hpp"
#include <wavelet.hpp>
#include <utilities.hpp>
#include <image_io.hpp>
#include <ostream>
#include <cmath>
rgb_wavelet_coefficients rgb_wavelet_coefficients::calculate(const raw_rgb_image& image){
static const int size = 512;
rgb_wavelet_coefficients::pre_fingerprint rgb_wavelet_coefficients::pre_calculate(av::frame const & frame) {
auto const image = to_raw_rgb_image(crop_to_square(frame), size, size);
rgb_wavelet_coefficients::pre_fingerprint ret;
// for every color
for(unsigned int color = 0; color < 3; ++color){
auto & vector = ret[color];
vector.assign(make_u(image.width() * image.height()), 0);
for(unsigned int n = 0; n < make_u(image.width() * image.height()); ++n){
vector[n] = 2.0 * image.data[3*n + color] / double(255) - 1.0;
}
wvlt::wavelet_2D(vector.data(), make_u(image.width()), make_u(image.height()));
}
return ret;
}
rgb_wavelet_coefficients rgb_wavelet_coefficients::calculate(av::frame const & frame){
auto const image = to_raw_rgb_image(crop_to_square(frame), size, size);
rgb_wavelet_coefficients ret;
std::vector<double> vector(make_u(image.width() * image.height()));
std::vector<double> vector(make_u(image.width() * image.height()), 0);
// for every color
for(unsigned int color = 0; color < 3; ++color){
@ -24,12 +47,12 @@ rgb_wavelet_coefficients rgb_wavelet_coefficients::calculate(const raw_rgb_image
auto copy = vector;
for(auto & x : copy) x = std::abs(x);
auto n_coefficients = coefficient_array.size();
auto const n_coefficients = coefficient_array.size();
std::nth_element(copy.begin(), copy.begin() + n_coefficients, copy.end(), std::greater<double>());
double threshold = copy[n_coefficients-1];
auto const threshold = copy[n_coefficients-1];
for(unsigned int n = 0; n < vector.size(); ++n){
auto x = vector[n];
auto const x = vector[n];
if(std::abs(x) >= threshold) {
coefficient_array[array_index++] = std::make_pair(n, x);
}
@ -46,38 +69,16 @@ static double square(double x){
return x*x;
}
double rgb_wavelet_coefficients::distance_to(const rgb_wavelet_coefficients& y) const {
double rgb_wavelet_coefficients::distance_to(pre_fingerprint const & fingerprint) const {
double distance = 0;
for(unsigned int color = 0; color < 3; ++color){
unsigned int i = 0, j = 0;
auto& x_array = color == 0 ? reds : (color == 1 ? greens : blues);
auto& y_array = color == 0 ? y.reds : (color == 1 ? y.greens : y.blues);
// "merge"
while(i < x_array.size() && j < y_array.size()){
auto x_pair = x_array[i];
auto y_pair = y_array[j];
auto const & coefficients = color == 0 ? reds : (color == 1 ? greens : blues);
if(x_pair.first == y_pair.first) {
distance += square(y_pair.second - x_pair.second);
++i;
++j;
} else if(x_pair.first < y_pair.first) {
distance += square(x_pair.second);
++i;
} else {
distance += square(y_pair.second);
++j;
}
}
// remaining part, either x or y
for(; i < x_array.size(); ++i){
distance += square(x_array[i].second);
}
for(; j < y_array.size(); ++j){
distance += square(y_array[j].second);
for(auto&& p : coefficients){
auto const x = p.second;
auto const y = fingerprint[color][p.first];
distance += square(x - y) - square(y);
}
}
@ -95,10 +96,12 @@ std::ostream& operator<<(std::ostream& out, rgb_wavelet_coefficients const & x){
out << "rgb_wavelet_coefficients" << std::endl;
for(int color = 0; color < 3; ++color){
auto& coefficient_array = color == 0 ? x.reds : (color == 1 ? x.greens : x.blues);
auto const & coefficient_array = color == 0 ? x.reds : (color == 1 ? x.greens : x.blues);
out << '[' << coefficient_array[0];
for(unsigned int i = 1; i < coefficient_array.size(); ++i) out << ", " << coefficient_array[i];
for(unsigned int i = 1; i < coefficient_array.size(); ++i) {
out << ", " << coefficient_array[i];
}
out << ']' << std::endl;
}
return out;

22
lib/fingerprint.hpp → lib/fingerprints/wavelet.hpp

@ -1,6 +1,7 @@
#pragma once
#include "image_io.hpp"
#include <av.hpp>
#include <fingerprint_traits.hpp>
#include <boost/serialization/access.hpp>
#include <boost/serialization/array.hpp>
@ -9,6 +10,7 @@
#include <utility>
#include <array>
#include <iosfwd>
#include <vector>
namespace boost {
namespace serialization {
@ -19,28 +21,18 @@ namespace boost {
} // namespace serialization
} // namespace boost
// Default implementation
template <typename Fingerprint>
struct fingerprint_traits {
static Fingerprint calculate(raw_rgb_image const & image) {
return Fingerprint::calculate(image);
}
static auto distance(Fingerprint const & x, Fingerprint const & y) {
return x.distance_to(y);
}
};
struct rgb_wavelet_coefficients {
// a double for (x, y) location represented in a single int
using coefficient = std::pair<int, double>;
using pre_fingerprint = std::array<std::vector<double>, 3>;
std::array<coefficient, 20> reds;
std::array<coefficient, 20> greens;
std::array<coefficient, 20> blues;
static rgb_wavelet_coefficients calculate(raw_rgb_image const & image);
double distance_to(rgb_wavelet_coefficients const & y) const;
static pre_fingerprint pre_calculate(av::frame const & frame);
static rgb_wavelet_coefficients calculate(av::frame const & frame);
double distance_to(pre_fingerprint const & fingerprint) const;
private:
friend class boost::serialization::access;

2
lib/image_database.cpp

@ -1,2 +0,0 @@
#include "image_database.hpp"

16
lib/image_database.hpp

@ -1,7 +1,7 @@
#pragma once
#include <image_io.hpp>
#include <fingerprint.hpp>
#include <fingerprints.hpp>
#include <boost/serialization/access.hpp>
#include <boost/serialization/vector.hpp>
@ -13,9 +13,9 @@ template <typename Fingerprint, typename Traits = fingerprint_traits<Fingerprint
struct image_database {
using index = size_t;
void add(std::string filename){
auto image = open_as_rgb(filename);
auto fingerprint = Traits::calculate(image);
void add(std::string const & filename){
auto && image = open_image(filename);
auto && fingerprint = Traits::calculate(image);
filenames.push_back(filename);
fingerprints.push_back(fingerprint);
@ -33,14 +33,14 @@ struct image_database {
return fingerprints.size();
}
index nearest_image(raw_rgb_image const & image) const {
auto fingerprint = Traits::calculate(image);
index nearest_image(av::frame const & image) const {
const auto && pre_fingerprint = Traits::pre_calculate(image);
index best_index = 0;
auto best_distance = Traits::distance(fingerprint, fingerprints[0]);
auto && best_distance = Traits::distance(fingerprints[0], pre_fingerprint);
for(index i = 1; i < fingerprints.size(); ++i){
auto distance = Traits::distance(fingerprint, fingerprints[i]);
const auto && distance = Traits::distance(fingerprints[i], pre_fingerprint);
if(distance < best_distance) {
best_distance = distance;
best_index = i;

63
lib/image_io.cpp

@ -103,6 +103,10 @@ void crop_to_square(av::frame& frame){
if(ret < 0) throw std::runtime_error("boem crop");
}
av::frame crop_to_square(const av::frame& frame){
return crop_to_square(av::frame_clone(frame));
}
av::frame crop_to_square(av::frame && frame){
crop_to_square(frame);
return std::move(frame);
@ -120,13 +124,14 @@ raw_rgb_image to_raw_rgb_image(av::frame const & frame, int new_width, int new_h
}
void apply_to_tiles(const std::string& filename, int h_tiles, int v_tiles, std::function<void (int, int, raw_rgb_image const &)> fun){
void apply_to_tiles(std::string const & filename, int h_tiles, int v_tiles, std::function<void(int, int, av::frame const &)> fun) {
auto org_frame = open_image(filename);
// create clone to crop
av::frame cropped_frame = av::frame_clone(org_frame);
// create raw buffer for the callback
// TODO: do not scale the cropped region
raw_rgb_image image(512, 512);
// create the tiles
@ -144,7 +149,61 @@ void apply_to_tiles(const std::string& filename, int h_tiles, int v_tiles, std::
sws_scale (context, {cropped_frame->data}, {cropped_frame->linesize}, 0, cropped_frame->height, {image.frame->data}, {image.frame->linesize});
sws_freeContext(context);
fun(c, r, image);
fun(c, r, image.frame);
}
}
}
void save_as_jpg(av::frame const & frame, std::string const & filename){
const auto pix_fmt = AV_PIX_FMT_YUVJ444P;
const auto codec_id= AV_CODEC_ID_MJPEG;
// Convert
int tile_width = 800;
int tile_height = 600;
int h_tiles = 8;
int v_tiles = 6;
std::vector<uint8_t, av::allocator<uint8_t>> data(make_u(avpicture_get_size(pix_fmt, h_tiles * tile_width, v_tiles * tile_height)), 0);
av::frame converted_frame = av::frame_alloc();
avpicture_fill(reinterpret_cast<AVPicture*>(converted_frame.get()), data.data(), pix_fmt, h_tiles * tile_width, v_tiles * tile_height);
converted_frame->width = h_tiles * tile_width;
converted_frame->height = v_tiles * tile_height;
converted_frame->format = pix_fmt;
auto const sws_context = sws_getContext(frame->width, frame->height, av::get_format(frame), tile_width, tile_height, av::get_format(converted_frame), 0, nullptr, nullptr, nullptr);
if(!sws_context) throw std::runtime_error("boem sws context");
av::frame cropped_frame = av::frame_clone(converted_frame);
for(int r = 0; r < v_tiles; ++r) {
for(int c = 0; c < h_tiles; ++c){
av_picture_crop(reinterpret_cast<AVPicture*>(cropped_frame.get()), reinterpret_cast<AVPicture*>(converted_frame.get()), av::get_format(converted_frame), r * tile_height, c * tile_width);
sws_scale (sws_context, {frame->data}, {frame->linesize}, 0, frame->height, {cropped_frame->data}, {cropped_frame->linesize});
}
}
sws_freeContext(sws_context);
// Encode
auto const codec = avcodec_find_encoder(codec_id);
if(!codec) throw av::error("Could not find codec");
auto codec_ctx = std::unique_ptr<AVCodecContext, av::deleter<AVCodecContext>>(avcodec_alloc_context3(codec), [](auto x){ avcodec_free_context(&x); });
if(!codec_ctx) throw av::error("Could not allocate codec context");
codec_ctx->pix_fmt = pix_fmt;
codec_ctx->width = converted_frame->width;
codec_ctx->height = converted_frame->height;
codec_ctx->time_base = av_make_q(1, 1);
auto const opened_codec = av::codec_open(codec_ctx.get(), codec, nullptr);
auto const buffer_size = avpicture_get_size(pix_fmt, codec_ctx->width, codec_ctx->height);
std::vector<uint8_t> buffer(make_u(buffer_size), 0);
auto const output_size = avcodec_encode_video(codec_ctx.get(), buffer.data(), buffer_size, converted_frame.get());
assert(output_size <= buffer_size);
auto const file = fopen(filename.c_str(), "wb");
fwrite(buffer.data(), 1, make_u(output_size), file);
fclose(file);
}

6
lib/image_io.hpp

@ -28,6 +28,7 @@ av::frame open_image(std::string const & filename);
// crops to the bottom right square (cheap operation)
void crop_to_square(av::frame & frame);
av::frame crop_to_square(av::frame const & frame);
av::frame crop_to_square(av::frame && frame);
// converts and resizes
@ -39,4 +40,7 @@ inline raw_rgb_image open_as_rgb(const std::string &filename){
}
// apply function to every tile, fun :: Column, Row, Image -> Void
void apply_to_tiles(std::string const & filename, int h_tiles, int v_tiles, std::function<void(int, int, raw_rgb_image const &)> fun);
void apply_to_tiles(std::string const & filename, int h_tiles, int v_tiles, std::function<void(int, int, av::frame const &)> fun);
// does what you think it does
void save_as_jpg(av::frame const & frame, std::string const & filename);

3
src/compress.cpp

@ -50,6 +50,7 @@ int main(){
}
}
save_as_ppm(image, "output.ppm");
// TODO: save as jpg
save_as_jpg(image.frame, "output.ppm");
}

10
src/fingerprint_test.cpp

@ -1,4 +1,5 @@
#include <fingerprint.hpp>
#include <fingerprints.hpp>
#include <image_io.hpp>
extern "C" {
#include <libavformat/avformat.h>
@ -10,10 +11,11 @@ using namespace std;
int main(){
av_register_all();
auto image = open_as_rgb("test.jpg");
auto const image = open_image("test.jpg");
rgb_wavelet_coefficients x = rgb_wavelet_coefficients::calculate(image);
auto const x = rgb_wavelet_coefficients::calculate(image);
auto const y = rgb_wavelet_coefficients::pre_calculate(image);
cout << x << endl;
cout << x.distance_to(x) << endl;
cout << x.distance_to(y) << endl;
}

51
src/main.cpp

@ -1,7 +1,7 @@
#include <image_io.hpp>
#include <wavelet.hpp>
#include <image_database.hpp>
#include <fingerprint.hpp>
#include <fingerprints.hpp>
#include <boost/filesystem.hpp>
#include <boost/archive/binary_oarchive.hpp>
@ -21,6 +21,9 @@ extern "C" {
#include <map>
#include <set>
static const int tile_width = 128;
static const int tile_height = 128;
using namespace std;
namespace fs = boost::filesystem;
namespace ar = boost::archive;
@ -29,15 +32,15 @@ using Database = image_database<rgb_wavelet_coefficients>;
using Mozaic = map<pair<int, int>, string>;
Database read_database(string const & database_directory){
image_database<rgb_wavelet_coefficients> db;
auto database_file = database_directory + ".db";
Database db;
auto const database_file = database_directory + ".db";
if (!boost::filesystem::exists(database_file)){
fs::path directory(database_directory);
fs::path const directory(database_directory);
fs::directory_iterator eod;
for(fs::directory_iterator it(directory); it != eod; ++it){
auto && path = it->path();
auto ext = path.extension();
auto const path = it->path();
auto const ext = path.extension();
if(ext != ".png" && ext != ".jpg") continue;
cout << colors::green("adding: ") << path.string() << endl;
@ -50,7 +53,6 @@ Database read_database(string const & database_directory){
} else {
ifstream file(database_file);
ar::binary_iarchive archive(file);
// read class state from archive
archive >> db;
}
@ -59,10 +61,10 @@ Database read_database(string const & database_directory){
}
Mozaic create_mozaic(Database const & db, string const & filename, int h_tiles, int v_tiles){
map<pair<int, int>, string> mozaic;
Mozaic mozaic;
apply_to_tiles("image.jpg", h_tiles, v_tiles, [&](int c, int r, raw_rgb_image const & image){
auto index = db.nearest_image(image);
apply_to_tiles("image.jpg", 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);
});
@ -71,11 +73,8 @@ Mozaic create_mozaic(Database const & db, string const & filename, int h_tiles,
}
void save_mozaic(Mozaic const & mozaic, string filename, int h_tiles, int v_tiles){
const auto pix_fmt = AV_PIX_FMT_YUVJ444P;
const auto codec_id= AV_CODEC_ID_MJPEG;
int tile_width = 128;
int tile_height = 128;
auto const pix_fmt = AV_PIX_FMT_YUVJ444P;
auto const codec_id= AV_CODEC_ID_MJPEG;
// Open all files we need
map<string, av::frame> frames;
@ -85,8 +84,8 @@ void save_mozaic(Mozaic const & mozaic, string filename, int h_tiles, int v_tile
frames.emplace(x.second, crop_to_square(open_image(x.second)));
}
auto total_width = h_tiles * tile_width;
auto total_height = v_tiles * tile_height;
auto const total_width = h_tiles * tile_width;
auto const total_height = v_tiles * tile_height;
// Create output frame
std::vector<uint8_t, av::allocator<uint8_t>> data(make_u(avpicture_get_size(pix_fmt, total_width, total_height)), 0);
@ -128,9 +127,9 @@ void save_mozaic(Mozaic const & mozaic, string filename, int h_tiles, int v_tile
codec_ctx->time_base = av_make_q(1, 1);
auto opened_codec = av::codec_open(codec_ctx.get(), codec, nullptr);
const auto buffer_size = avpicture_get_size(pix_fmt, codec_ctx->width, codec_ctx->height);
auto const buffer_size = avpicture_get_size(pix_fmt, codec_ctx->width, codec_ctx->height);
std::vector<uint8_t> buffer(make_u(buffer_size), 0);
auto output_size = avcodec_encode_video(codec_ctx.get(), buffer.data(), buffer_size, frame.get());
auto const output_size = avcodec_encode_video(codec_ctx.get(), buffer.data(), buffer_size, frame.get());
assert(output_size <= buffer_size);
cout << "output size" << output_size << endl;
@ -142,14 +141,14 @@ void save_mozaic(Mozaic const & mozaic, string filename, int h_tiles, int v_tile
int main(){
av_register_all();
string database_directory = "database";
string filename = "image.jpg";
string output = "output.jpg";
int h_tiles = 4 * 13;
int v_tiles = 3 * 13;
string const database_directory = "database";
string const filename = "image.jpg";
string const output = "output.jpg";
int const h_tiles = 4 * 7;
int const v_tiles = 3 * 7;
const auto db = read_database(database_directory);
const auto mozaic = create_mozaic(db, filename, h_tiles, v_tiles);
auto const db = read_database(database_directory);
auto const mozaic = create_mozaic(db, filename, h_tiles, v_tiles);
save_mozaic(mozaic, output, h_tiles, v_tiles);
// debugging

14
src/needle.cpp

@ -1,7 +1,7 @@
#include <image_io.hpp>
#include <wavelet.hpp>
#include <image_database.hpp>
#include <fingerprint.hpp>
#include <fingerprints.hpp>
#include <boost/filesystem.hpp>
@ -19,16 +19,16 @@ namespace fs = boost::filesystem;
int main(){
av_register_all();
string database_directory = "database";
string filename = "needle.jpg";
string const database_directory = "database";
string const filename = "needle.jpg";
image_database<rgb_wavelet_coefficients> db;
fs::path directory(database_directory);
fs::path const directory(database_directory);
fs::directory_iterator eod;
for(fs::directory_iterator it(directory); it != eod; ++it){
auto && path = it->path();
auto ext = path.extension();
auto const path = it->path();
auto const ext = path.extension();
if(ext != ".png" && ext != ".jpg") continue;
cout << colors::green("adding: ") << path.string() << endl;
@ -40,7 +40,7 @@ int main(){
cout << colors::green("database: ") << db.size() << endl;
cout << colors::green("press enter to search match for: ") << filename << endl;
cin.ignore();
auto index = db.nearest_image(open_as_rgb(filename));
auto const index = db.nearest_image(open_image(filename));
cout << colors::green("match: ") << db.filename(index) << endl;
}
}

58
src/writer.cpp

@ -9,67 +9,11 @@ extern "C" {
using namespace std;
static void save_as_jpg(av::frame const & frame, std::string const & filename){
const auto pix_fmt = AV_PIX_FMT_YUVJ444P;
const auto codec_id= AV_CODEC_ID_MJPEG;
// Convert
int tile_width = 800;
int tile_height = 600;
int h_tiles = 8;
int v_tiles = 6;
std::vector<uint8_t, av::allocator<uint8_t>> data(make_u(avpicture_get_size(pix_fmt, h_tiles * tile_width, v_tiles * tile_height)), 0);
av::frame converted_frame = av::frame_alloc();
avpicture_fill(reinterpret_cast<AVPicture*>(converted_frame.get()), data.data(), pix_fmt, h_tiles * tile_width, v_tiles * tile_height);
converted_frame->width = h_tiles * tile_width;
converted_frame->height = v_tiles * tile_height;
converted_frame->format = pix_fmt;
auto sws_context = sws_getContext(frame->width, frame->height, av::get_format(frame), tile_width, tile_height, av::get_format(converted_frame), 0, nullptr, nullptr, nullptr);
if(!sws_context) throw std::runtime_error("boem sws context");
av::frame cropped_frame = av::frame_clone(converted_frame);
for(int r = 0; r < v_tiles; ++r) {
for(int c = 0; c < h_tiles; ++c){
av_picture_crop(reinterpret_cast<AVPicture*>(cropped_frame.get()), reinterpret_cast<AVPicture*>(converted_frame.get()), av::get_format(converted_frame), r * tile_height, c * tile_width);
sws_scale (sws_context, {frame->data}, {frame->linesize}, 0, frame->height, {cropped_frame->data}, {cropped_frame->linesize});
}
}
sws_freeContext(sws_context);
// Encode
auto codec = avcodec_find_encoder(codec_id);
if(!codec) throw av::error("Could not find codec");
auto codec_ctx = std::unique_ptr<AVCodecContext, av::deleter<AVCodecContext>>(avcodec_alloc_context3(codec), [](auto x){ avcodec_free_context(&x); });
if(!codec_ctx) throw av::error("Could not allocate codec context");
codec_ctx->pix_fmt = pix_fmt;
codec_ctx->width = converted_frame->width;
codec_ctx->height = converted_frame->height;
codec_ctx->time_base = av_make_q(1, 1);
auto opened_codec = av::codec_open(codec_ctx.get(), codec, nullptr);
const auto buffer_size = avpicture_get_size(pix_fmt, codec_ctx->width, codec_ctx->height);
std::vector<uint8_t> buffer(make_u(buffer_size), 0);
auto output_size = avcodec_encode_video(codec_ctx.get(), buffer.data(), buffer_size, converted_frame.get());
assert(output_size <= buffer_size);
cout << "output size" << output_size << endl;
auto file = fopen(filename.c_str(), "wb");
fwrite(buffer.data(), 1, make_u(output_size), file);
fclose(file);
}
int main(){
av_register_all();
while(true){
auto image = open_image("needle.png");
auto const image = open_image("needle.png");
save_as_jpg(image, "output.jpg");
}
}

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