X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=src%2Flib%2Fdcp_video.cc;h=4a505a7e18e65996b4666d59f541e67b0f993c06;hb=c162f9d8b127f56b8da46b83908000611033e6a5;hp=7b529c45a205df6d52bb8bec964819271ab76ede;hpb=c150d49754daa77f70ba0d47ab5948747e10a7d4;p=dcpomatic.git

diff --git a/src/lib/dcp_video.cc b/src/lib/dcp_video.cc
index 7b529c45a..4a505a7e1 100644
--- a/src/lib/dcp_video.cc
+++ b/src/lib/dcp_video.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2016 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2021 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -18,6 +18,7 @@
 
 */
 
+
 /** @file  src/dcp_video_frame.cc
  *  @brief A single frame of video destined for a DCP.
  *
@@ -28,23 +29,25 @@
  *  of images that require encoding.
  */
 
-#include "dcp_video.h"
+
+#include "compose.hpp"
 #include "config.h"
-#include "exceptions.h"
-#include "encode_server_description.h"
+#include "cross.h"
+#include "dcp_video.h"
+#include "dcpomatic_log.h"
 #include "dcpomatic_socket.h"
+#include "encode_server_description.h"
+#include "exceptions.h"
 #include "image.h"
 #include "log.h"
-#include "dcpomatic_log.h"
-#include "cross.h"
 #include "player_video.h"
-#include "compose.hpp"
+#include "rng.h"
 #include "warnings.h"
 #include <libcxml/cxml.h>
 #include <dcp/raw_convert.h>
 #include <dcp/openjpeg_image.h>
 #include <dcp/rgb_xyz.h>
-#include <dcp/j2k.h>
+#include <dcp/j2k_transcode.h>
 DCPOMATIC_DISABLE_WARNINGS
 #include <libxml++/libxml++.h>
 DCPOMATIC_ENABLE_WARNINGS
@@ -125,10 +128,13 @@ DCPVideo::encode_locally ()
 	auto const comment = Config::instance()->dcp_j2k_comment();
 
 	ArrayData enc = {};
-	int constexpr minimum_size = 65536;
+	/* This was empirically derived by a user: see #1902 */
+	int const minimum_size = 16384;
+	LOG_GENERAL ("Using minimum frame size %1", minimum_size);
 
 	auto xyz = convert_to_xyz (_frame, boost::bind(&Log::dcp_log, dcpomatic_log.get(), _1, _2));
 	int noise_amount = 2;
+	int pixel_skip = 16;
 	while (true) {
 		enc = dcp::compress_j2k (
 			xyz,
@@ -140,9 +146,12 @@ DCPVideo::encode_locally ()
 		);
 
 		if (enc.size() >= minimum_size) {
+			LOG_GENERAL (N_("Frame %1 encoded size was OK (%2)"), _index, enc.size());
 			break;
 		}
 
+		LOG_GENERAL (N_("Frame %1 encoded size was small (%2); adding noise at level %3 with pixel skip %4"), _index, enc.size(), noise_amount, pixel_skip);
+
 		/* The JPEG2000 is too low-bitrate for some decoders <cough>DSS200</cough> so add some noise
 		 * and try again.  This is slow but hopefully won't happen too often.  We have to do
 		 * convert_to_xyz() again because compress_j2k() corrupts its xyz parameter.
@@ -151,17 +160,23 @@ DCPVideo::encode_locally ()
 		xyz = convert_to_xyz (_frame, boost::bind(&Log::dcp_log, dcpomatic_log.get(), _1, _2));
 		auto size = xyz->size ();
 		auto pixels = size.width * size.height;
+		dcpomatic::RNG rng(42);
 		for (auto c = 0; c < 3; ++c) {
 			auto p = xyz->data(c);
-			for (auto i = 0; i < pixels; ++i) {
-				*p = std::min(4095, std::max(0, *p + rand() % noise_amount));
-				++p;
+			auto e = xyz->data(c) + pixels;
+			while (p < e) {
+				*p = std::min(4095, std::max(0, *p + (rng.get() % noise_amount)));
+				p += pixel_skip;
 			}
 		}
 
-		++noise_amount;
+		if (pixel_skip > 1) {
+			--pixel_skip;
+		} else {
+			++noise_amount;
+		}
 		/* Something's gone badly wrong if this much noise doesn't help */
-		DCP_ASSERT (noise_amount < 16);
+		DCPOMATIC_ASSERT (noise_amount < 16);
 	}
 
 	switch (_frame->eyes()) {
@@ -212,7 +227,7 @@ DCPVideo::encode_remotely (EncodeServerDescription serv, int timeout)
 		/* Send XML metadata */
 		auto xml = doc.write_to_string ("UTF-8");
 		socket->write (xml.length() + 1);
-		socket->write ((uint8_t *) xml.c_str(), xml.length() + 1);
+		socket->write ((uint8_t *) xml.c_str(), xml.bytes() + 1);
 
 		/* Send binary data */
 		LOG_TIMING("start-remote-send thread=%1", thread_id ());