Fix calculation of compression level for ZSTD

debian/changelog

@@ -1,80 +0,0 @@
-libxisf (0.2.12-ubuntu1) focal; urgency=medium
-
-  * Fix bug in writing ICCProfile
-  * Fix handling big +2GiB images
-
- -- Dušan Poizl <nou@nouspiro.space>  Sat, 23 Mar 2024 09:25:46 +0100
-
-libxisf (0.2.11-ubuntu1) focal; urgency=medium
-
-  * Fix not loading String properties
-  * Convert aperture and focal length from mm to meters
-
- -- Dušan Poizl <nou@nouspiro.space>  Fri, 05 Jan 2024 16:18:32 +0100
-
-libxisf (0.2.10-ubuntu1) focal; urgency=medium
-
-  * Fix writing incorrect header size
-
- -- Dušan Poizl <nou@nouspiro.space>  Tue, 17 Oct 2023 20:33:05 +0200
-
-libxisf (0.2.9-ubuntu1) focal; urgency=medium
-
-  * Add support for ZSTD
-
- -- Dušan Poizl <nou@nouspiro.space>  Mon, 14 Aug 2023 10:32:30 +0200
-
-libxisf (0.2.6-ubuntu1) focal; urgency=medium
-
-  * Add method for ICC profile
-  * pkg-config file support
-
- -- Dušan Poizl <nou@nouspiro.space>  Fri, 02 Jun 2023 09:16:59 +0200
-
-libxisf (0.2.4-ubuntu1) focal; urgency=medium
-
-  * Add getThumbnail method
-
- -- Dušan Poizl <nou@nouspiro.space>  Tue, 19 May 2023 19:23:34 +0200
-
-libxisf (0.2.3-ubuntu1) focal; urgency=medium
-
-  * Fix Color filter array
-
- -- Dušan Poizl <nou@nouspiro.space>  Tue, 11 Apr 2023 12:39:41 +0200
-
-libxisf (0.2.0-ubuntu2) focal; urgency=medium
-
-  * Fix lintian errors
-
- -- Dušan Poizl <nou@nouspiro.space>  Sun, 19 Mar 2023 22:10:39 +0100
-
-libxisf (0.2.0-ubuntu1) focal; urgency=medium
-
-  * Rewrite to remove Qt as dependency
-
- -- Dušan Poizl <nou@nouspiro.space>  Fri, 10 Mar 2023 22:10:01 +0100
-
-libxisf (0.1.3-ubuntu1) focal; urgency=medium
-
-  * Write missing pixelStorage attribute
-
- -- Dušan Poizl <nou@nouspiro.space>  Fri, 17 Feb 2023 16:57:30 +0100
-
-libxisf (0.1.2-ubuntu1) focal; urgency=medium
-
-  * Add qtbase5-dev as dependency to libxisf-dev
-
- -- Dušan Poizl <nou@nouspiro.space>  Thu, 09 Feb 2023 21:28:45 +0100
-
-libxisf (0.1.1-ubuntu1) focal; urgency=medium
-
-  * Fixed packaging
-
- -- Dušan Poizl <nou@nouspiro.space>  Wed, 08 Feb 2023 18:57:50 +0100
-
-libxisf (0.1.0-ubuntu1) focal; urgency=low
-
-  * Initial release.
-
- -- Dušan Poizl <nou@nouspiro.space>  Tue, 07 Feb 2023 10:47:08 +0100

debian/compat

@@ -1 +0,0 @@
-10

debian/control

@@ -1,45 +0,0 @@
-Source: libxisf
-Priority: optional
-Maintainer: Dušan Poizl <nou@nouspiro.space>
-Build-Depends: debhelper (>= 9),
-               cdbs,
-               cmake,
-               pkg-config,
-               liblz4-dev,
-               libpugixml-dev,
-               zlib1g-dev,
-               libzstd-dev
-Standards-Version: 4.5.0
-Section: libs
-Homepage: https://gitea.nouspiro.space/nou/libXISF
-Vcs-Git: https://gitea.nouspiro.space/nou/libXISF.git
-
-Package: libxisf-dev
-Section: libdevel
-Architecture: any
-Multi-Arch: same
-Depends: libxisf (= ${binary:Version}), ${misc:Depends}
-Description: Library to load and save XISF images development files
- This package contain development files.
- .
- XISF is native format of PixInsight astroprocessing suite.
- Extensible Image Serialization Format (XISF) is the native file format
- of PixInsight. It is a free, open format for storage, management and
- interchange of digital images and associated data.
- .
- This C++ library implements XISF specification 1.0 which can be found at
- https://pixinsight.com/doc/docs/XISF-1.0-spec/XISF-1.0-spec.html
-
-Package: libxisf
-Architecture: any
-Multi-Arch: same
-Depends: ${shlibs:Depends}, ${misc:Depends}
-Conflicts: libxisf0
-Description: Library to load and save XISF images
- XISF is native format of PixInsight astroprocessing suite.
- Extensible Image Serialization Format (XISF) is the native file format
- of PixInsight. It is a free, open format for storage, management and
- interchange of digital images and associated data.
- .
- This C++ library implements XISF specification 1.0 which can be found at
- https://pixinsight.com/doc/docs/XISF-1.0-spec/XISF-1.0-spec.html

debian/copyright

@@ -1,97 +0,0 @@
-Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
-Upstream-Name: libxisf
-Source: https://gitea.nouspiro.space/nou/libXISF
-
-Files: * debian/*
-Copyright: (c) 2023 <Dušan Poizl nou@nouspiro.space>
-License: GPL-3+
- This program is free software: you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation, either version 3 of the License, or
- (at your option) any later version.
- .
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- GNU General Public License for more details.
- .
- You should have received a copy of the GNU General Public License
- along with this program.  If not, see <http://www.gnu.org/licenses/>.
- .
- On Debian systems, the complete texts of the GNU General Public Licenses
- version 2 and 3 can be found in '/usr/share/common-licenses/GPL-2' and
- '/usr/share/common-licenses/GPL-3'.
-
-Files: lz4/*
-Copyright: (c) 2011-2020, Yann Collet
-License: BSD-2-clause
- LZ4 Library
- Copyright (c) 2011-2020, Yann Collet
- All rights reserved.
- .
- Redistribution and use in source and binary forms, with or without modification,
- are permitted provided that the following conditions are met:
- .
- * Redistributions of source code must retain the above copyright notice, this
- list of conditions and the following disclaimer.
- .
- * Redistributions in binary form must reproduce the above copyright notice, this
- list of conditions and the following disclaimer in the documentation and/or
- other materials provided with the distribution.
- .
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
- ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-Files: zlib/*
-Copyright: (c) 1995-2022 Jean-loup Gailly and Mark Adler
-License: Zlib
- This software is provided 'as-is', without any express or implied
- warranty.  In no event will the authors be held liable for any damages
- arising from the use of this software.
- .
- Permission is granted to anyone to use this software for any purpose,
- including commercial applications, and to alter it and redistribute it
- freely, subject to the following restrictions:
- .
- 1. The origin of this software must not be misrepresented; you must not
-    claim that you wrote the original software. If you use this software
-    in a product, an acknowledgment in the product documentation would be
-    appreciated but is not required.
- 2. Altered source versions must be plainly marked as such, and must not be
-    misrepresented as being the original software.
- 3. This notice may not be removed or altered from any source distribution.
- .
- Jean-loup Gailly        Mark Adler
- jloup@gzip.org          madler@alumni.caltech.edu
-
-Files: pugixml/*
-Copyright: (c) 2006-2022 Arseny Kapoulkine
-License: MIT
- Permission is hereby granted, free of charge, to any person
- obtaining a copy of this software and associated documentation
- files (the "Software"), to deal in the Software without
- restriction, including without limitation the rights to use,
- copy, modify, merge, publish, distribute, sublicense, and/or sell
- copies of the Software, and to permit persons to whom the
- Software is furnished to do so, subject to the following
- conditions:
- .
- The above copyright notice and this permission notice shall be
- included in all copies or substantial portions of the Software.
- .
- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
- OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
- HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
- WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
- OTHER DEALINGS IN THE SOFTWARE.

debian/libxisf-dev.install

@@ -1,2 +0,0 @@
-usr/include
-usr/lib/*/*.so

debian/libxisf.install

@@ -1 +0,0 @@
-usr/lib/*/*.so.*

debian/rules

@@ -1,16 +0,0 @@
-#!/usr/bin/make -f
-
-export DEB_BUILD_MAINT_OPTIONS = hardening=+all
-export DEB_CFLAGS_MAINT_APPEND  = -Wall -pedantic
-export DEB_LDFLAGS_MAINT_APPEND = -Wl,--as-needed
-DEB_HOST_MULTIARCH ?= $(shell dpkg-architecture -qDEB_HOST_MULTIARCH)
-DPKG_EXPORT_BUILDFLAGS = 1
-include /usr/share/dpkg/buildflags.mk
-CFLAGS+=$(CPPFLAGS)
-CXXFLAGS+=$(CPPFLAGS)
-
-%:
-	dh $@
-
-override_dh_auto_configure:
-	dh_auto_configure -- -DCMAKE_LIBRARY_ARCHITECTURE="$(DEB_HOST_MULTIARCH)" -DUSE_BUNDLED_LIBS=Off

libxisf.cpp

@@ -23,6 +23,7 @@
 #include <iostream>
 #include <sstream>
 #include <cstdlib>
+#include <cmath>
 #include <lz4.h>
 #include <lz4hc.h>
 #include <pugixml.hpp>
@@ -486,7 +487,37 @@ DataBlock::CompressionCodec Image::compression() const
 void Image::setCompression(DataBlock::CompressionCodec compression, int level)
 {
     _dataBlock.codec = compression;
-    _dataBlock.compressLevel = level;
+    _dataBlock.compressLevel = -1;
+
+    level = std::min(std::max(level, -1), 100);
+
+    auto percentToRange = [](int val, int min, int max)
+    {
+        double slope = (max - min) / 100.0;
+        return std::round(min + slope * val);
+    };
+
+    if(level >= 0)
+    {
+        switch(compression)
+        {
+        case DataBlock::CompressionCodec::Zlib:
+            _dataBlock.compressLevel = percentToRange(level, Z_BEST_SPEED, Z_BEST_COMPRESSION);
+            break;
+        case DataBlock::CompressionCodec::LZ4:
+        case DataBlock::CompressionCodec::LZ4HC:
+            _dataBlock.compressLevel = percentToRange(level, 1, LZ4HC_CLEVEL_MAX);
+            break;
+        case DataBlock::CompressionCodec::ZSTD:
+#ifdef HAVE_ZSTD
+            _dataBlock.compressLevel = percentToRange(level, 0, ZSTD_maxCLevel());
+#endif
+            break;
+        default:
+            //nothing
+            break;
+        }
+    }
 }
 
 bool Image::byteShuffling() const
@@ -949,12 +980,12 @@ public:
     void save(ByteArray &data);
     void save(std::ostream &io);
     void writeImage(const Image &image);
+    static void writeFITSKeyword(pugi::xml_node &node, const FITSKeyword &keyword);
 private:
     void writeHeader();
     void writeImageElement(pugi::xml_node &node, const Image &image);
     void writeDataBlockAttributes(pugi::xml_node &image_node, const DataBlock &dataBlock);
     void writePropertyElement(pugi::xml_node &node, const Property &property);
-    void writeFITSKeyword(pugi::xml_node &node, const FITSKeyword &keyword);
     void writeMetadata(pugi::xml_node &node);
     void updateImageAttachmentPos(pugi::xml_node &root, size_t offset);
     ByteArray _xisfHeader;
@@ -1270,6 +1301,321 @@ void XISFWriter::writeImage(const Image &image)
     p->writeImage(image);
 }
 
+class XISFModifyPrivate
+{
+public:
+    void open(const String &name);
+    void open(const ByteArray &data);
+    /** Open image from istream. This method takes ownership of *io pointer */
+    void open(std::istream *io);
+    /** Close opended file release all data. */
+    void close();
+
+    void save(const String &name);
+    void save(ByteArray &data);
+    void save(std::ostream &io);
+
+    void addFITSKeyword(uint32_t image, const FITSKeyword &keyword);
+    void updateFITSKeyword(uint32_t image, const FITSKeyword &keyword, bool add);
+    void removeFITSKeyword(uint32_t image, const String &name);
+private:
+    void readXISFHeader();
+    void parseAttachmentPos(pugi::xml_node &root);
+    void updateAttachmentPos(pugi::xml_node &root, size_t offset);
+
+    std::unique_ptr<std::istream> _io;
+    std::unique_ptr<StreamBuffer> _buffer;
+
+    pugi::xml_document _doc;
+    pugi::xml_node _root;
+    std::map<int, std::pair<uint64_t, uint64_t>> _attachmentPos;// pair contain position and size
+    std::map<int, std::pair<uint64_t, uint64_t>> _attachmentPosNew;
+};
+
+
+void XISFModifyPrivate::open(const String &name)
+{
+    close();
+    _io = std::make_unique<std::ifstream>(name.c_str(), std::ios_base::in | std::ios_base::binary);
+    readXISFHeader();
+}
+
+void XISFModifyPrivate::open(const ByteArray &data)
+{
+    close();
+    _buffer = std::make_unique<StreamBuffer>(data);
+    _io = std::make_unique<std::istream>(_buffer.get());
+    readXISFHeader();
+}
+
+void XISFModifyPrivate::open(std::istream *io)
+{
+    close();
+    _io.reset(io);
+    readXISFHeader();
+}
+
+void XISFModifyPrivate::close()
+{
+    _io.reset();
+    _buffer.reset();
+    _root = pugi::xml_node();
+    _doc.reset();
+}
+
+void XISFModifyPrivate::save(const String &name)
+{
+    std::ofstream fw(name.c_str(), std::ios_base::out | std::ios_base::binary);
+
+    if(fw.fail())
+        throw Error("Failed to open file");
+
+    save(fw);
+}
+
+void XISFModifyPrivate::save(ByteArray &data)
+{
+    StreamBuffer buffer;
+    std::ostream oss(&buffer);
+    save(oss);
+    data = buffer.byteArray();
+}
+
+void XISFModifyPrivate::save(std::ostream &io)
+{
+    if(!_io || !_root)
+        throw Error("No input file opened");
+
+    const char signature[16] = {'X', 'I', 'S', 'F', '0', '1', '0', '0', 0, 0, 0, 0, 0, 0, 0, 0};
+
+    pugi::xml_document doc;
+    doc.append_child(pugi::node_comment).set_value("\nExtensible Image Serialization Format - XISF version 1.0\nCreated with libXISF - https://nouspiro.space\n");
+    pugi::xml_node root_copy = doc.append_copy(_root);
+
+    uint32_t size = 0;
+    std::string header;
+    while(true)
+    {
+        std::stringstream xml;
+        xml.write(signature, sizeof(signature));
+        doc.save(xml, "", pugi::format_raw);
+        header = xml.str();
+        if(size != header.size())
+        {
+            size = header.size();
+            updateAttachmentPos(root_copy, size);
+        }
+        else
+        {
+            break;
+        }
+    }
+
+    uint32_t headerSize = header.size() - sizeof(signature);
+    header.replace(8, sizeof(uint32_t), (const char*)&headerSize, sizeof(uint32_t));
+
+    io.write(header.c_str(), header.size());
+    const uint64_t BLOCK_SIZE = 1024*1024*4;
+    std::vector<char> data(BLOCK_SIZE);
+    for(auto &pos : _attachmentPos)
+    {
+        uint64_t oldPos = pos.second.first;
+        uint64_t size = pos.second.second;
+
+        _io->seekg(oldPos);
+        while(size)
+        {
+            _io->read(&data[0], std::min(size, BLOCK_SIZE));
+            io.write(&data[0], std::min(size, BLOCK_SIZE));
+            size -= std::min(size, BLOCK_SIZE);
+        }
+    }
+}
+
+void XISFModifyPrivate::addFITSKeyword(uint32_t image, const FITSKeyword &keyword)
+{
+    if(!_root)
+        throw Error("No input file opened");
+
+    pugi::xpath_node_set images = _root.select_nodes("//Image");
+
+    if(image >= images.size())
+        throw Error("Out of bounds");
+
+    pugi::xml_node imageNode = images[image].node();
+    XISFWriterPrivate::writeFITSKeyword(imageNode, keyword);
+}
+
+void XISFModifyPrivate::updateFITSKeyword(uint32_t image, const FITSKeyword &keyword, bool add)
+{
+    if(!_root)
+        throw Error("No input file opened");
+
+    pugi::xpath_node_set images = _root.select_nodes("//Image");
+
+    if(image >= images.size())
+        throw Error("Out of bounds");
+
+    pugi::xpath_variable_set variables;
+    variables.set("name", keyword.name.c_str());
+    pugi::xml_node imageNode = images[image].node();
+    pugi::xml_node keywordNode = imageNode.select_node("FITSKeyword[@name=string($name)]", &variables).node();
+
+    if(keywordNode)
+    {
+        if(keywordNode.attribute("value"))
+            keywordNode.attribute("value").set_value(keyword.value.c_str());
+        else
+            keywordNode.append_attribute("value").set_value(keyword.value.c_str());
+
+        if(keywordNode.attribute("comment"))
+            keywordNode.attribute("comment").set_value(keyword.comment.c_str());
+        else
+            keywordNode.append_attribute("comment").set_value(keyword.comment.c_str());
+    }
+    else if(add)
+    {
+        XISFWriterPrivate::writeFITSKeyword(imageNode, keyword);
+    }
+}
+
+void XISFModifyPrivate::removeFITSKeyword(uint32_t image, const String &name)
+{
+    if(!_root)
+        throw Error("No input file opened");
+
+    pugi::xpath_node_set images = _root.select_nodes("//Image");
+
+    if(image >= images.size())
+        throw Error("Out of bounds");
+
+    pugi::xpath_variable_set variables;
+    variables.set("name", name.c_str());
+    pugi::xml_node imageNode = images[image].node();
+    pugi::xml_node keywordNode = imageNode.select_node("FITSKeyword[@name=string($name)]", &variables).node();
+
+    if(keywordNode)
+        imageNode.remove_child(keywordNode);
+}
+
+void XISFModifyPrivate::readXISFHeader()
+{
+    char signature[8];
+    _io->read(signature, sizeof(signature));
+    if(_io->fail())
+        throw Error("Failed to read from file");
+
+    if(memcmp(signature, "XISF0100", sizeof(signature)) != 0)
+        throw Error("Not valid XISF 1.0 file");
+
+    uint32_t headerLen[2] = {0};
+    _io->read((char*)&headerLen, sizeof(headerLen));
+
+    ByteArray xisfHeader(headerLen[0]);
+    _io->read(xisfHeader.data(), headerLen[0]);
+
+    _doc.load_buffer(xisfHeader.data(), xisfHeader.size());
+
+    _root = _doc.child("xisf");
+
+    parseAttachmentPos(_root);
+
+    if(!_root || _root.attribute("version").as_string() != std::string("1.0"))
+        throw Error("Unknown root XML element");
+}
+
+void XISFModifyPrivate::parseAttachmentPos(pugi::xml_node &root)
+{
+    pugi::xpath_node_set locationAttributes = root.select_nodes("//@location");
+    int i = 0;
+    for(auto &attr : locationAttributes)
+    {
+        std::string locationStr = attr.attribute().as_string();
+        std::vector<std::string> location = splitString(locationStr, ':');
+        if(location.size() >= 3 && location[0] == "attachment")
+        {
+            uint64_t attachmentPos = std::stoull(location[1]);
+            uint64_t attachmentSize = std::stoull(location[2]);
+            _attachmentPos[i] = {attachmentPos, attachmentSize};
+        }
+        i++;
+    }
+}
+
+void XISFModifyPrivate::updateAttachmentPos(pugi::xml_node &root, size_t offset)
+{
+    pugi::xpath_node_set locationAttributes = root.select_nodes("//@location");
+    for(auto &pos : _attachmentPos)
+    {
+        pugi::xml_attribute attr = locationAttributes[pos.first].attribute();
+        uint64_t attachmentSize = pos.second.second;
+        std::string locationStr = "attachment:" + std::to_string(offset) + ":" + std::to_string(attachmentSize);
+        _attachmentPosNew[pos.first] = pos.second;
+        offset += attachmentSize;
+        attr.set_value(locationStr.c_str());
+    }
+}
+
+XISFModify::XISFModify()
+{
+    p = new XISFModifyPrivate();
+}
+
+XISFModify::~XISFModify()
+{
+    delete p;
+}
+
+void XISFModify::open(const String &name)
+{
+    p->open(name);
+}
+
+void XISFModify::open(const ByteArray &data)
+{
+    p->open(data);
+}
+
+void XISFModify::open(std::istream *io)
+{
+    p->open(io);
+}
+
+void XISFModify::close()
+{
+    p->close();
+}
+
+void XISFModify::save(const String &name)
+{
+    p->save(name);
+}
+
+void XISFModify::save(ByteArray &data)
+{
+    p->save(data);
+}
+
+void XISFModify::save(std::ostream &io)
+{
+    p->save(io);
+}
+
+void XISFModify::addFITSKeyword(uint32_t image, const FITSKeyword &keyword)
+{
+    p->addFITSKeyword(image, keyword);
+}
+
+void XISFModify::updateFITSKeyword(uint32_t image, const FITSKeyword &keyword, bool add)
+{
+    p->updateFITSKeyword(image, keyword, add);
+}
+
+void XISFModify::removeFITSKeyword(uint32_t image, const String &name)
+{
+    p->removeFITSKeyword(image, name);
+}
+
 #define STRING_ENUM(map, map2, c, e) { map.insert({#e, c::e}); map2.insert({c::e, #e}); }
 
 struct Init

libxisf.h

@@ -35,6 +35,7 @@ namespace LibXISF
 
 class XISFReaderPrivate;
 class XISFWriterPrivate;
+class XISFModifyPrivate;
 
 class LIBXISF_EXPORT ByteArray
 {
@@ -316,6 +317,11 @@ public:
     const T* imageData() const { return static_cast<T*>(imageData()); }
     size_t imageDataSize() const;
     DataBlock::CompressionCodec compression() const;
+    /** Set compression type and level.
+     *  @param compression define which compression algorithm to use.
+     *  @param level number between 0 and 100. Zero means lowest compression and maximum speed. Hundred means maximum compression speed.
+     *  -1 means default compression level defined by compression library.
+     */
     void setCompression(DataBlock::CompressionCodec compression, int level = -1);
     bool byteShuffling() const;
     void setByteshuffling(bool enable);
@@ -405,6 +411,42 @@ public:
     const char* what() const noexcept { return _msg.c_str(); }
 };
 
+class LIBXISF_EXPORT XISFModify
+{
+public:
+    XISFModify();
+    virtual ~XISFModify();
+    void open(const String &name);
+    void open(const ByteArray &data);
+    void open(std::istream *io);
+    void close();
+    void save(const String &name);
+    void save(ByteArray &data);
+    void save(std::ostream &io);
+
+    /**
+     * @brief addFITSKeyword append new keyword to image
+     * @param image index of image to update
+     * @param keyword that will be added
+     */
+    void addFITSKeyword(uint32_t image, const FITSKeyword &keyword);
+    /**
+     * @brief updateFITSKeyword update keyword with same name
+     * @param image index of image to update
+     * @param keyword that will be updated
+     * @param add if true then it will add new keyword in case that it doesn't exists
+     */
+    void updateFITSKeyword(uint32_t image, const FITSKeyword &keyword, bool add);
+    /**
+     * @brief removeFITSKeyword remove keyword with name from image
+     * @param image index of image to update
+     * @param name of keyword that will be removed
+     */
+    void removeFITSKeyword(uint32_t image, const String &name);
+private:
+    XISFModifyPrivate *p;
+};
+
 template<typename T>
 constexpr Image::SampleFormat Image::sampleFormatEnum()
 {

streambuffer.cpp

@@ -1,3 +1,21 @@
+/************************************************************************
+ * LibXISF - library to load and save XISF files                        *
+ * Copyright (C) 2024 Dušan Poizl                                       *
+ *                                                                      *
+ * This program is free software: you can redistribute it and/or modify *
+ * it under the terms of the GNU General Public License as published by *
+ * the Free Software Foundation, either version 3 of the License, or    *
+ * (at your option) any later version.                                  *
+ *                                                                      *
+ * This program is distributed in the hope that it will be useful,      *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of       *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
+ * GNU General Public License for more details.                         *
+ *                                                                      *
+ * You should have received a copy of the GNU General Public License    *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.*
+ ************************************************************************/
+
 #include "streambuffer.h"
 
 namespace LibXISF

streambuffer.h

@@ -1,3 +1,21 @@
+/************************************************************************
+ * LibXISF - library to load and save XISF files                        *
+ * Copyright (C) 2024 Dušan Poizl                                       *
+ *                                                                      *
+ * This program is free software: you can redistribute it and/or modify *
+ * it under the terms of the GNU General Public License as published by *
+ * the Free Software Foundation, either version 3 of the License, or    *
+ * (at your option) any later version.                                  *
+ *                                                                      *
+ * This program is distributed in the hope that it will be useful,      *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of       *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
+ * GNU General Public License for more details.                         *
+ *                                                                      *
+ * You should have received a copy of the GNU General Public License    *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.*
+ ************************************************************************/
+
 #ifndef STREAMBUFFER_H
 #define STREAMBUFFER_H