diff --git a/src/imageformats/kra.cpp b/src/imageformats/kra.cpp
index 368a836..9945d08 100644
--- a/src/imageformats/kra.cpp
+++ b/src/imageformats/kra.cpp
@@ -1,88 +1,91 @@
 /* This file is part of the KDE project
    Copyright (C) 2013 Boudewijn Rempt <boud@valdyas.org>
 
    This program is free software; you can redistribute it and/or
    modify it under the terms of the Lesser GNU General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
 
    This code is based on Thacher Ulrich PSD loading code released
    on public domain. See: http://tulrich.com/geekstuff/
 */
 
 #include "kra.h"
 
 #include <kzip.h>
 
 #include <QImage>
 #include <QIODevice>
 #include <QFile>
 
+static constexpr char s_magic[] = "application/x-krita";
+static constexpr int s_magic_size = strlen(s_magic);
+
 KraHandler::KraHandler()
 {
 }
 
 bool KraHandler::canRead() const
 {
     if (canRead(device())) {
         setFormat("kra");
         return true;
     }
     return false;
 }
 
 bool KraHandler::read(QImage *image)
 {
     KZip zip(device());
     if (!zip.open(QIODevice::ReadOnly)) return false;
 
     const KArchiveEntry *entry = zip.directory()->entry(QLatin1String("mergedimage.png"));
     if (!entry || !entry->isFile()) return false;
 
     const KZipFileEntry* fileZipEntry = static_cast<const KZipFileEntry*>(entry);
 
     image->loadFromData(fileZipEntry->data(), "PNG");
 
     return true;
 }
 
 bool KraHandler::canRead(QIODevice *device)
 {
     if (!device) {
         qWarning("KraHandler::canRead() called with no device");
         return false;
     }
 
     char buff[57];
     if (device->peek(buff, sizeof(buff)) == sizeof(buff))
-        return qstrcmp(buff + 0x26, "application/x-krita") == 0;
+        return memcmp(buff + 0x26, s_magic, s_magic_size) == 0;
 
     return false;
 }
 
 QImageIOPlugin::Capabilities KraPlugin::capabilities(QIODevice *device, const QByteArray &format) const
 {
     if (format == "kra" || format == "KRA") {
         return Capabilities(CanRead);
     }
     if (!format.isEmpty()) {
         return {};
     }
     if (!device->isOpen()) {
         return {};
     }
 
     Capabilities cap;
     if (device->isReadable() && KraHandler::canRead(device)) {
         cap |= CanRead;
     }
     return cap;
 }
 
 QImageIOHandler *KraPlugin::create(QIODevice *device, const QByteArray &format) const
 {
     QImageIOHandler *handler = new KraHandler;
     handler->setDevice(device);
     handler->setFormat(format);
     return handler;
 }
diff --git a/src/imageformats/ora.cpp b/src/imageformats/ora.cpp
index bc5558f..792181f 100644
--- a/src/imageformats/ora.cpp
+++ b/src/imageformats/ora.cpp
@@ -1,87 +1,90 @@
 /* This file is part of the KDE project
    Copyright (C) 2013 Boudewijn Rempt <boud@valdyas.org>
 
    This program is free software; you can redistribute it and/or
    modify it under the terms of the Lesser GNU General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
 
    This code is based on Thacher Ulrich PSD loading code released
    on public domain. See: http://tulrich.com/geekstuff/
 */
 
 #include "ora.h"
 
 #include <QImage>
 #include <QScopedPointer>
 
 #include <kzip.h>
 
+static constexpr char s_magic[] = "image/openraster";
+static constexpr int s_magic_size = strlen(s_magic);
+
 OraHandler::OraHandler()
 {
 }
 
 bool OraHandler::canRead() const
 {
     if (canRead(device())) {
         setFormat("ora");
         return true;
     }
     return false;
 }
 
 bool OraHandler::read(QImage *image)
 {
     KZip zip(device());
     if (!zip.open(QIODevice::ReadOnly)) return false;
 
     const KArchiveEntry *entry = zip.directory()->entry(QLatin1String("mergedimage.png"));
     if (!entry || !entry->isFile()) return false;
 
     const KZipFileEntry* fileZipEntry = static_cast<const KZipFileEntry*>(entry);
 
     image->loadFromData(fileZipEntry->data(), "PNG");
 
     return true;
 }
 
 bool OraHandler::canRead(QIODevice *device)
 {
     if (!device) {
         qWarning("OraHandler::canRead() called with no device");
         return false;
     }
 
     char buff[54];
     if (device->peek(buff, sizeof(buff)) == sizeof(buff))
-        return qstrcmp(buff + 0x26, "image/openraster") == 0;
+        return memcmp(buff + 0x26, s_magic, s_magic_size) == 0;
 
     return false;
 }
 
 QImageIOPlugin::Capabilities OraPlugin::capabilities(QIODevice *device, const QByteArray &format) const
 {
     if (format == "ora" || format == "ORA") {
         return Capabilities(CanRead);
     }
     if (!format.isEmpty()) {
         return {};
     }
     if (!device->isOpen()) {
         return {};
     }
 
     Capabilities cap;
     if (device->isReadable() && OraHandler::canRead(device)) {
         cap |= CanRead;
     }
     return cap;
 }
 
 QImageIOHandler *OraPlugin::create(QIODevice *device, const QByteArray &format) const
 {
     QImageIOHandler *handler = new OraHandler;
     handler->setDevice(device);
     handler->setFormat(format);
     return handler;
 }