Add a test to explore a bug with some bad encoding quality (#2361).

diff --git a/test/colour_conversion_test.cc b/test/colour_conversion_test.cc
index c48a0b63a6c19b6d171e16a0f70717638b46a6b7..933588f49b75569d7886701c1a5d72b61acc1cb9 100644 (file)
--- a/test/colour_conversion_test.cc
+++ b/test/colour_conversion_test.cc
@@ -25,9 +25,17 @@
  */
 
 
+#include "lib/butler.h"
 #include "lib/colour_conversion.h"
+#include "lib/content_factory.h"
+#include "lib/dcp_video.h"
 #include "lib/film.h"
+#include "lib/player.h"
+#include "lib/video_content.h"
+#include "test.h"
 #include <dcp/gamma_transfer_function.h>
+#include <dcp/openjpeg_image.h>
+#include <dcp/j2k_transcode.h>
 #include <libxml++/libxml++.h>
 #include <boost/test/unit_test.hpp>
 #include <iostream>
@@ -36,6 +44,7 @@
 using std::cout;
 using std::make_shared;
 using std::shared_ptr;
+using std::vector;
 
 
 BOOST_AUTO_TEST_CASE (colour_conversion_test1)
@@ -121,3 +130,49 @@ BOOST_AUTO_TEST_CASE (colour_conversion_test4)
                BOOST_CHECK (ColourConversion::from_xml(in, Film::current_state_version).get() == i.conversion);
        }
 }
+
+
+BOOST_AUTO_TEST_CASE(noisy_blacks_test)
+{
+       auto content = content_factory(TestPaths::private_data() / "island.mov").front();
+       auto film = new_test_film2("noisy_black_test", { content });
+
+       Player player(film, Image::Alignment::COMPACT);
+       player.set_fast();
+       player.set_always_burn_open_subtitles();
+       player.set_play_referenced();
+
+       auto butler = make_shared<Butler>(
+               film, player, AudioMapping(), 2, boost::bind(PlayerVideo::force, AV_PIX_FMT_RGB24), VideoRange::FULL, Image::Alignment::PADDED, true, false, Butler::Audio::DISABLED
+               );
+
+       auto video = butler->get_video(Butler::Behaviour::BLOCKING).first;
+
+       vector<int> bitrates = { 50, 100, 150, 200, 250 };
+
+       for (auto bitrate: bitrates) {
+               auto before_encode = DCPVideo::convert_to_xyz(video, [](dcp::NoteType, std::string) {});
+               write_openjpeg_image(before_encode, String::compose("build/test/noisy_black_test_%1_before.opj", bitrate));
+               auto encoded = DCPVideo(video, 0, 24, bitrate * 1000000LL, Resolution::FOUR_K).encode_locally();
+               auto after_decode = dcp::decompress_j2k(encoded, 0);
+               write_openjpeg_image(after_decode, String::compose("build/test/noisy_black_test_%1_after.opj", bitrate));
+
+               int max_diffs[] = { 0, 0, 0 };
+
+               int const width = video->out_size().width;
+               int const height = video->out_size().height;
+
+               for (int y = 0; y < height; ++y) {
+                       for (int x = 0; x < width; ++x) {
+                               int offset = y * width + x;
+                               for (int c = 0; c < 3; ++c) {
+                                       auto const diff = std::abs(before_encode->data(c)[offset] - after_decode->data(c)[offset]);
+                                       max_diffs[c] = std::max(max_diffs[c], diff);
+                               }
+                       }
+               }
+
+               std::cout << bitrate << "MBps diffs; " << max_diffs[0] << " " << max_diffs[1] << " " << max_diffs[2] << "\n";
+       }
+}
+