From 59b844347c19c143e965ac767dc928a98c97fb17 Mon Sep 17 00:00:00 2001
From: Matthieu Darbois <mayeut@users.noreply.github.com>
Date: Mon, 22 Dec 2014 15:50:32 +0000
Subject: [PATCH] [trunk] fixed component precision upscaling in opj_decompress
 (fixes issue 458)

---
 src/bin/jp2/convert.c                   | 52 ++++++++++++++-----------
 tests/nonregression/md5refs.txt         |  4 ++
 tests/nonregression/test_suite.ctest.in |  3 ++
 3 files changed, 37 insertions(+), 22 deletions(-)

diff --git a/src/bin/jp2/convert.c b/src/bin/jp2/convert.c
index d56f3904..7f4593b0 100644
--- a/src/bin/jp2/convert.c
+++ b/src/bin/jp2/convert.c
@@ -102,43 +102,51 @@ void clip_component(opj_image_comp_t* component, OPJ_UINT32 precision)
 }
 
 /* Component precision scaling */
+static void scale_component_up(opj_image_comp_t* component, OPJ_UINT32 precision)
+{
+	OPJ_SIZE_T i, len;
+	
+	len = (OPJ_SIZE_T)component->w * (OPJ_SIZE_T)component->h;
+	if (component->sgnd) {
+		OPJ_INT64  newMax = (1U << (precision - 1));
+		OPJ_INT64  oldMax = (1U << (component->prec - 1));
+		OPJ_INT32* l_data = component->data;
+		for (i = 0; i < len; ++i) {
+			l_data[i] = (OPJ_INT32)(((OPJ_INT64)l_data[i] * newMax) / oldMax);
+		}
+	} else {
+		OPJ_UINT64  newMax = (1U << precision) - 1U;
+		OPJ_UINT64  oldMax = (1U << component->prec) - 1U;
+		OPJ_UINT32* l_data = (OPJ_UINT32*)component->data;
+		for (i = 0; i < len; ++i) {
+			l_data[i] = (OPJ_UINT32)(((OPJ_UINT64)l_data[i] * newMax) / oldMax);
+		}
+	}
+	component->prec = precision;
+}
 void scale_component(opj_image_comp_t* component, OPJ_UINT32 precision)
 {
 	int shift;
-	OPJ_SIZE_T i;
-	OPJ_SIZE_T len;
+	OPJ_SIZE_T i, len;
 	
 	if (component->prec == precision) {
 		return;
 	}
 	if (component->prec < precision) {
-		shift = (int)(precision - component->prec);
-	} else {
-		shift = (int)(component->prec - precision);
+		scale_component_up(component, precision);
+		return;
 	}
+	shift = (int)(component->prec - precision);
 	len = (OPJ_SIZE_T)component->w * (OPJ_SIZE_T)component->h;
-	
 	if (component->sgnd) {
 		OPJ_INT32* l_data = component->data;
-		if (component->prec < precision) {
-			for (i = 0; i < len; ++i) {
-				l_data[i] <<= shift;
-			}
-		} else {
-			for (i = 0; i < len; ++i) {
-				l_data[i] >>= shift;
-			}
+		for (i = 0; i < len; ++i) {
+			l_data[i] >>= shift;
 		}
 	} else {
 		OPJ_UINT32* l_data = (OPJ_UINT32*)component->data;
-		if (component->prec < precision) {
-			for (i = 0; i < len; ++i) {
-				l_data[i] <<= shift;
-			}
-		} else {
-			for (i = 0; i < len; ++i) {
-				l_data[i] >>= shift;
-			}
+		for (i = 0; i < len; ++i) {
+			l_data[i] >>= shift;
 		}
 	}
 	component->prec = precision;
diff --git a/tests/nonregression/md5refs.txt b/tests/nonregression/md5refs.txt
index 40043c08..eb04c0ba 100644
--- a/tests/nonregression/md5refs.txt
+++ b/tests/nonregression/md5refs.txt
@@ -175,3 +175,7 @@ d5ecef537edf294af83826763c0cf860  issue411-ycc422.jp2_1.pgx
 07480962d25b3d8cce18096648963c8a  issue411-ycc420.jp2_0.pgx
 149a69831b42401f20b8f7492ef99d97  issue411-ycc420.jp2_1.pgx
 ec8d1c99db9763a8ba489df4f41dda53  issue411-ycc420.jp2_2.pgx
+3c7ff2e4bdae849167be36589f32bcd5  issue458.jp2_0.pgx
+f004b48eafb2e52529cc9c7b6a3ff5d2  issue458.jp2_1.pgx
+3127bd0a591d113c3c2428c8d2c14ec8  issue458.jp2_2.pgx
+dacaf60e4c430916a8c2a9ebec32e71c  issue458.jp2_3.pgx
diff --git a/tests/nonregression/test_suite.ctest.in b/tests/nonregression/test_suite.ctest.in
index 7f5d6f08..0cd5387f 100644
--- a/tests/nonregression/test_suite.ctest.in
+++ b/tests/nonregression/test_suite.ctest.in
@@ -258,6 +258,9 @@ opj_decompress -i @INPUT_NR_PATH@/issue411-ycc420.jp2 -o @TEMP_PATH@/issue411-yc
 !opj_decompress -i @INPUT_NR_PATH@/issue427-null-image-size.jp2 -o @TEMP_PATH@/issue427-null-image-size.jp2.pgx
 # issue 427 illegal tile offset
 !opj_decompress -i @INPUT_NR_PATH@/issue427-illegal-tile-offset.jp2 -o @TEMP_PATH@/issue427-illegal-tile-offset.jp2.pgx
+# issue 458 component precision upscaling
+opj_decompress -i @INPUT_NR_PATH@/issue458.jp2 -o @TEMP_PATH@/issue458.jp2.pgx
+
 
 # decode with specific area
 # prec=12; nb_c=1