Mirco Miranda 374961dab4 Improve CMYK writing support
Closes #11 

Requires MR !279

On formats that does not support CMYK and does not use the ScanLineConverter class during write operation, the CMYK images must be converted using the color space conversion functions of `QImage` (if ICC profile is valid).
2024-11-28 06:57:01 +00:00

920 lines
21 KiB
C++

/*
kimgio module for SGI images
SPDX-FileCopyrightText: 2004 Melchior FRANZ <mfranz@kde.org>
SPDX-License-Identifier: LGPL-2.0-or-later
*/
/* this code supports:
* reading:
* everything, except images with 1 dimension or images with
* mapmode != NORMAL (e.g. dithered); Images with 16 bit
* precision or more than 4 layers are stripped down.
* writing:
* Run Length Encoded (RLE) or Verbatim (uncompressed)
* (whichever is smaller)
*
* Please report if you come across rgb/rgba/sgi/bw files that aren't
* recognized. Also report applications that can't deal with images
* saved by this filter.
*/
#include "rgb_p.h"
#include "util_p.h"
#include <cstring>
#include <QColorSpace>
#include <QDebug>
#include <QImage>
#include <QList>
#include <QMap>
class RLEData : public QList<uchar>
{
public:
RLEData()
{
}
RLEData(const uchar *d, uint l, uint o)
: _offset(o)
{
for (uint i = 0; i < l; i++) {
append(d[i]);
}
}
bool operator<(const RLEData &) const;
void write(QDataStream &s);
uint offset() const
{
return _offset;
}
private:
uint _offset;
};
class RLEMap : public QMap<RLEData, uint>
{
public:
RLEMap()
: _counter(0)
, _offset(0)
{
}
uint insert(const uchar *d, uint l);
QList<const RLEData *> vector();
void setBaseOffset(uint o)
{
_offset = o;
}
private:
uint _counter;
uint _offset;
};
class SGIImagePrivate
{
public:
SGIImagePrivate();
~SGIImagePrivate();
bool readImage(QImage &);
bool writeImage(const QImage &);
bool isValid() const;
bool isSupported() const;
bool peekHeader(QIODevice *device);
QSize size() const;
QImage::Format format() const;
void setDevice(QIODevice *device);
private:
enum {
NORMAL,
DITHERED,
SCREEN,
COLORMAP,
}; // colormap
QIODevice *_dev;
QDataStream _stream;
quint16 _magic = 0;
quint8 _rle = 0;
quint8 _bpc = 0;
quint16 _dim = 0;
quint16 _xsize = 0;
quint16 _ysize = 0;
quint16 _zsize = 0;
quint32 _pixmin = 0;
quint32 _pixmax = 0;
char _imagename[80];
quint32 _colormap = 0;
quint8 _unused[404];
quint32 _unused32 = 0;
quint32 *_starttab;
quint32 *_lengthtab;
QByteArray _data;
QByteArray::Iterator _pos;
RLEMap _rlemap;
QList<const RLEData *> _rlevector;
uint _numrows;
bool readData(QImage &);
bool getRow(uchar *dest);
bool readHeader();
static bool readHeader(QDataStream &ds, SGIImagePrivate *sgi);
bool writeHeader();
bool writeRle();
bool writeVerbatim(const QImage &);
bool scanData(const QImage &);
uint compact(uchar *, uchar *);
uchar intensity(uchar);
};
SGIImagePrivate::SGIImagePrivate()
: _dev(nullptr)
, _starttab(nullptr)
, _lengthtab(nullptr)
{
std::memset(_imagename, 0, sizeof(_imagename));
std::memset(_unused, 0, sizeof(_unused));
}
SGIImagePrivate::~SGIImagePrivate()
{
delete[] _starttab;
delete[] _lengthtab;
}
///////////////////////////////////////////////////////////////////////////////
void SGIImagePrivate::setDevice(QIODevice *device)
{
_dev = device;
_stream.setDevice(_dev);
}
bool SGIImagePrivate::getRow(uchar *dest)
{
int n;
int i;
if (!_rle) {
for (i = 0; i < _xsize; i++) {
if (_pos >= _data.end()) {
return false;
}
dest[i] = uchar(*_pos);
_pos += _bpc;
}
return true;
}
for (i = 0; i < _xsize;) {
if (_bpc == 2) {
_pos++;
}
if (_pos >= _data.end()) {
return false;
}
n = *_pos & 0x7f;
if (!n) {
break;
}
if (*_pos++ & 0x80) {
for (; i < _xsize && _pos < _data.end() && n--; i++) {
*dest++ = *_pos;
_pos += _bpc;
}
} else {
for (; i < _xsize && n--; i++) {
*dest++ = *_pos;
}
_pos += _bpc;
}
}
return i == _xsize;
}
bool SGIImagePrivate::readData(QImage &img)
{
QRgb *c;
quint32 *start = _starttab;
QByteArray lguard(_xsize, 0);
uchar *line = (uchar *)lguard.data();
unsigned x;
unsigned y;
if (!_rle) {
_pos = _data.begin();
}
for (y = 0; y < _ysize; y++) {
if (_rle) {
_pos = _data.begin() + *start++;
}
if (!getRow(line)) {
return false;
}
c = reinterpret_cast<QRgb *>(img.scanLine(_ysize - y - 1));
for (x = 0; x < _xsize; x++, c++) {
*c = qRgb(line[x], line[x], line[x]);
}
}
if (_zsize == 1) {
return true;
}
if (_zsize != 2) {
for (y = 0; y < _ysize; y++) {
if (_rle) {
_pos = _data.begin() + *start++;
}
if (!getRow(line)) {
return false;
}
c = reinterpret_cast<QRgb *>(img.scanLine(_ysize - y - 1));
for (x = 0; x < _xsize; x++, c++) {
*c = qRgb(qRed(*c), line[x], line[x]);
}
}
for (y = 0; y < _ysize; y++) {
if (_rle) {
_pos = _data.begin() + *start++;
}
if (!getRow(line)) {
return false;
}
c = reinterpret_cast<QRgb *>(img.scanLine(_ysize - y - 1));
for (x = 0; x < _xsize; x++, c++) {
*c = qRgb(qRed(*c), qGreen(*c), line[x]);
}
}
if (_zsize == 3) {
return true;
}
}
for (y = 0; y < _ysize; y++) {
if (_rle) {
_pos = _data.begin() + *start++;
}
if (!getRow(line)) {
return false;
}
c = reinterpret_cast<QRgb *>(img.scanLine(_ysize - y - 1));
for (x = 0; x < _xsize; x++, c++) {
*c = qRgba(qRed(*c), qGreen(*c), qBlue(*c), line[x]);
}
}
return true;
}
bool SGIImagePrivate::readImage(QImage &img)
{
if (!readHeader() || !isSupported()) {
return false;
}
if (_stream.atEnd()) {
return false;
}
img = imageAlloc(size(), format());
if (img.isNull()) {
qWarning() << "Failed to allocate image, invalid dimensions?" << QSize(_xsize, _ysize);
return false;
}
if (_zsize > 4) {
// qDebug() << "using first 4 of " << _zsize << " channels";
// Only let this continue if it won't cause a int overflow later
// this is most likely a broken file anyway
if (_ysize > std::numeric_limits<int>::max() / _zsize) {
return false;
}
}
_numrows = _ysize * _zsize;
if (_rle) {
uint l;
_starttab = new quint32[_numrows];
for (l = 0; !_stream.atEnd() && l < _numrows; l++) {
_stream >> _starttab[l];
_starttab[l] -= 512 + _numrows * 2 * sizeof(quint32);
if (_stream.status() != QDataStream::Ok) {
return false;
}
}
for (; l < _numrows; l++) {
_starttab[l] = 0;
}
_lengthtab = new quint32[_numrows];
for (l = 0; !_stream.atEnd() && l < _numrows; l++) {
_stream >> _lengthtab[l];
if (_stream.status() != QDataStream::Ok) {
return false;
}
}
}
if (_stream.status() != QDataStream::Ok) {
return false;
}
_data = _dev->readAll();
// sanity check
if (_rle) {
for (uint o = 0; o < _numrows; o++) {
// don't change to greater-or-equal!
if (_starttab[o] + _lengthtab[o] > (uint)_data.size()) {
// qDebug() << "image corrupt (sanity check failed)";
return false;
}
}
}
if (!readData(img)) {
// qDebug() << "image corrupt (incomplete scanline)";
return false;
}
return true;
}
///////////////////////////////////////////////////////////////////////////////
void RLEData::write(QDataStream &s)
{
for (int i = 0; i < size(); i++) {
s << at(i);
}
}
bool RLEData::operator<(const RLEData &b) const
{
uchar ac;
uchar bc;
for (int i = 0; i < qMin(size(), b.size()); i++) {
ac = at(i);
bc = b[i];
if (ac != bc) {
return ac < bc;
}
}
return size() < b.size();
}
uint RLEMap::insert(const uchar *d, uint l)
{
RLEData data = RLEData(d, l, _offset);
Iterator it = find(data);
if (it != end()) {
return it.value();
}
_offset += l;
return QMap<RLEData, uint>::insert(data, _counter++).value();
}
QList<const RLEData *> RLEMap::vector()
{
QList<const RLEData *> v(size());
for (Iterator it = begin(); it != end(); ++it) {
v.replace(it.value(), &it.key());
}
return v;
}
uchar SGIImagePrivate::intensity(uchar c)
{
if (c < _pixmin) {
_pixmin = c;
}
if (c > _pixmax) {
_pixmax = c;
}
return c;
}
uint SGIImagePrivate::compact(uchar *d, uchar *s)
{
uchar *dest = d;
uchar *src = s;
uchar patt;
uchar *t;
uchar *end = s + _xsize;
int i;
int n;
while (src < end) {
for (n = 0, t = src; t + 2 < end && !(*t == t[1] && *t == t[2]); t++) {
n++;
}
while (n) {
i = n > 126 ? 126 : n;
n -= i;
*dest++ = 0x80 | i;
while (i--) {
*dest++ = *src++;
}
}
if (src == end) {
break;
}
patt = *src++;
for (n = 1; src < end && *src == patt; src++) {
n++;
}
while (n) {
i = n > 126 ? 126 : n;
n -= i;
*dest++ = i;
*dest++ = patt;
}
}
*dest++ = 0;
return dest - d;
}
bool SGIImagePrivate::scanData(const QImage &img)
{
quint32 *start = _starttab;
QByteArray lineguard(_xsize * 2, 0);
QByteArray bufguard(_xsize, 0);
uchar *line = (uchar *)lineguard.data();
uchar *buf = (uchar *)bufguard.data();
const QRgb *c;
unsigned x;
unsigned y;
uint len;
for (y = 0; y < _ysize; y++) {
const int yPos = _ysize - y - 1; // scanline doesn't do any sanity checking
if (yPos >= img.height()) {
qWarning() << "Failed to get scanline for" << yPos;
return false;
}
c = reinterpret_cast<const QRgb *>(img.scanLine(yPos));
for (x = 0; x < _xsize; x++) {
buf[x] = intensity(qRed(*c++));
}
len = compact(line, buf);
*start++ = _rlemap.insert(line, len);
}
if (_zsize == 1) {
return true;
}
if (_zsize != 2) {
for (y = 0; y < _ysize; y++) {
const int yPos = _ysize - y - 1;
if (yPos >= img.height()) {
qWarning() << "Failed to get scanline for" << yPos;
return false;
}
c = reinterpret_cast<const QRgb *>(img.scanLine(yPos));
for (x = 0; x < _xsize; x++) {
buf[x] = intensity(qGreen(*c++));
}
len = compact(line, buf);
*start++ = _rlemap.insert(line, len);
}
for (y = 0; y < _ysize; y++) {
const int yPos = _ysize - y - 1;
if (yPos >= img.height()) {
qWarning() << "Failed to get scanline for" << yPos;
return false;
}
c = reinterpret_cast<const QRgb *>(img.scanLine(yPos));
for (x = 0; x < _xsize; x++) {
buf[x] = intensity(qBlue(*c++));
}
len = compact(line, buf);
*start++ = _rlemap.insert(line, len);
}
if (_zsize == 3) {
return true;
}
}
for (y = 0; y < _ysize; y++) {
const int yPos = _ysize - y - 1;
if (yPos >= img.height()) {
qWarning() << "Failed to get scanline for" << yPos;
return false;
}
c = reinterpret_cast<const QRgb *>(img.scanLine(yPos));
for (x = 0; x < _xsize; x++) {
buf[x] = intensity(qAlpha(*c++));
}
len = compact(line, buf);
*start++ = _rlemap.insert(line, len);
}
return true;
}
bool SGIImagePrivate::isValid() const
{
// File signature/magic number
if (_magic != 0x01da) {
return false;
}
// Compression, 0 = Uncompressed, 1 = RLE compressed
if (_rle > 1) {
return false;
}
// Bytes per pixel, 1 = 8 bit, 2 = 16 bit
if (_bpc != 1 && _bpc != 2) {
return false;
}
// Image dimension, 3 for RGBA image
if (_dim < 1 || _dim > 3) {
return false;
}
// Number channels in the image file, 4 for RGBA image
if (_zsize < 1) {
return false;
}
return true;
}
bool SGIImagePrivate::isSupported() const
{
if (!isValid()) {
return false;
}
if (_colormap != NORMAL) {
return false; // only NORMAL supported
}
if (_dim == 1) {
return false;
}
return true;
}
bool SGIImagePrivate::peekHeader(QIODevice *device)
{
QDataStream ds(device->peek(512));
return SGIImagePrivate::readHeader(ds, this) && isValid();
}
QSize SGIImagePrivate::size() const
{
return QSize(_xsize, _ysize);
}
QImage::Format SGIImagePrivate::format() const
{
if (_zsize == 2 || _zsize == 4) {
return QImage::Format_ARGB32;
}
return QImage::Format_RGB32;
}
bool SGIImagePrivate::readHeader()
{
return readHeader(_stream, this);
}
bool SGIImagePrivate::readHeader(QDataStream &ds, SGIImagePrivate *sgi)
{
// magic
ds >> sgi->_magic;
// verbatim/rle
ds >> sgi->_rle;
// bytes per channel
ds >> sgi->_bpc;
// number of dimensions
ds >> sgi->_dim;
ds >> sgi->_xsize >> sgi->_ysize >> sgi->_zsize >> sgi->_pixmin >> sgi->_pixmax >> sgi->_unused32;
// name
ds.readRawData(sgi->_imagename, 80);
sgi->_imagename[79] = '\0';
ds >> sgi->_colormap;
for (size_t i = 0; i < sizeof(_unused); i++) {
ds >> sgi->_unused[i];
}
return ds.status() == QDataStream::Ok;
}
bool SGIImagePrivate::writeHeader()
{
_stream << _magic;
_stream << _rle << _bpc << _dim;
_stream << _xsize << _ysize << _zsize;
_stream << _pixmin << _pixmax;
_stream << _unused32;
for (int i = 0; i < 80; i++) {
_imagename[i] = '\0';
}
_stream.writeRawData(_imagename, 80);
_stream << _colormap;
for (size_t i = 0; i < sizeof(_unused); i++) {
_stream << _unused[i];
}
return _stream.status() == QDataStream::Ok;
}
bool SGIImagePrivate::writeRle()
{
_rle = 1;
// qDebug() << "writing RLE data";
if (!writeHeader()) {
return false;
}
uint i;
// write start table
for (i = 0; i < _numrows; i++) {
_stream << quint32(_rlevector[_starttab[i]]->offset());
}
// write length table
for (i = 0; i < _numrows; i++) {
_stream << quint32(_rlevector[_starttab[i]]->size());
}
// write data
for (i = 0; (int)i < _rlevector.size(); i++) {
const_cast<RLEData *>(_rlevector[i])->write(_stream);
}
return _stream.status() == QDataStream::Ok;
}
bool SGIImagePrivate::writeVerbatim(const QImage &img)
{
_rle = 0;
if (!writeHeader()) {
return false;
}
const QRgb *c;
unsigned x;
unsigned y;
for (y = 0; y < _ysize; y++) {
c = reinterpret_cast<const QRgb *>(img.scanLine(_ysize - y - 1));
for (x = 0; x < _xsize; x++) {
_stream << quint8(qRed(*c++));
}
}
if (_zsize == 1) {
return _stream.status() == QDataStream::Ok;
}
if (_zsize != 2) {
for (y = 0; y < _ysize; y++) {
c = reinterpret_cast<const QRgb *>(img.scanLine(_ysize - y - 1));
for (x = 0; x < _xsize; x++) {
_stream << quint8(qGreen(*c++));
}
}
for (y = 0; y < _ysize; y++) {
c = reinterpret_cast<const QRgb *>(img.scanLine(_ysize - y - 1));
for (x = 0; x < _xsize; x++) {
_stream << quint8(qBlue(*c++));
}
}
if (_zsize == 3) {
return _stream.status() == QDataStream::Ok;
}
}
for (y = 0; y < _ysize; y++) {
c = reinterpret_cast<const QRgb *>(img.scanLine(_ysize - y - 1));
for (x = 0; x < _xsize; x++) {
_stream << quint8(qAlpha(*c++));
}
}
return _stream.status() == QDataStream::Ok;
}
bool SGIImagePrivate::writeImage(const QImage &image)
{
// qDebug() << "writing "; // TODO add filename
QImage img = image;
if (img.allGray()) {
_dim = 2, _zsize = 1;
} else {
_dim = 3, _zsize = 3;
}
auto hasAlpha = img.hasAlphaChannel();
if (hasAlpha) {
_dim = 3, _zsize++;
}
#if QT_VERSION >= QT_VERSION_CHECK(6, 8, 0)
auto cs = image.colorSpace();
if (cs.isValid() && cs.colorModel() == QColorSpace::ColorModel::Cmyk && image.format() == QImage::Format_CMYK8888) {
img = image.convertedToColorSpace(QColorSpace(QColorSpace::SRgb), QImage::Format_RGB32);
} else if (hasAlpha && img.format() != QImage::Format_ARGB32) {
#else
if (hasAlpha && img.format() != QImage::Format_ARGB32) {
#endif
img = img.convertToFormat(QImage::Format_ARGB32);
} else if (!hasAlpha && img.format() != QImage::Format_RGB32) {
img = img.convertToFormat(QImage::Format_RGB32);
}
if (img.isNull()) {
// qDebug() << "can't convert image to depth 32";
return false;
}
const int w = img.width();
const int h = img.height();
if (w > 65535 || h > 65535) {
return false;
}
_magic = 0x01da;
_bpc = 1;
_xsize = w;
_ysize = h;
_pixmin = ~0u;
_pixmax = 0;
_colormap = NORMAL;
_numrows = _ysize * _zsize;
_starttab = new quint32[_numrows];
_rlemap.setBaseOffset(512 + _numrows * 2 * sizeof(quint32));
if (!scanData(img)) {
// qDebug() << "this can't happen";
return false;
}
_rlevector = _rlemap.vector();
long verbatim_size = _numrows * _xsize;
long rle_size = _numrows * 2 * sizeof(quint32);
for (int i = 0; i < _rlevector.size(); i++) {
rle_size += _rlevector[i]->size();
}
if (verbatim_size <= rle_size) {
return writeVerbatim(img);
}
return writeRle();
}
///////////////////////////////////////////////////////////////////////////////
RGBHandler::RGBHandler()
: QImageIOHandler()
, d(new SGIImagePrivate)
{
}
bool RGBHandler::canRead() const
{
if (canRead(device())) {
setFormat("rgb");
return true;
}
return false;
}
bool RGBHandler::read(QImage *outImage)
{
d->setDevice(device());
return d->readImage(*outImage);
}
bool RGBHandler::write(const QImage &image)
{
d->setDevice(device());
return d->writeImage(image);
}
bool RGBHandler::supportsOption(ImageOption option) const
{
if (option == QImageIOHandler::Size) {
return true;
}
if (option == QImageIOHandler::ImageFormat) {
return true;
}
return false;
}
QVariant RGBHandler::option(ImageOption option) const
{
QVariant v;
if (option == QImageIOHandler::Size) {
auto &&sgi = d;
if (sgi->isSupported()) {
v = QVariant::fromValue(sgi->size());
} else if (auto dev = device()) {
if (d->peekHeader(dev) && sgi->isSupported()) {
v = QVariant::fromValue(sgi->size());
}
}
}
if (option == QImageIOHandler::ImageFormat) {
auto &&sgi = d;
if (sgi->isSupported()) {
v = QVariant::fromValue(sgi->format());
} else if (auto dev = device()) {
if (d->peekHeader(dev) && sgi->isSupported()) {
v = QVariant::fromValue(sgi->format());
}
}
}
return v;
}
bool RGBHandler::canRead(QIODevice *device)
{
if (!device) {
qWarning("RGBHandler::canRead() called with no device");
return false;
}
SGIImagePrivate sgi;
return sgi.peekHeader(device) && sgi.isSupported();
}
///////////////////////////////////////////////////////////////////////////////
QImageIOPlugin::Capabilities RGBPlugin::capabilities(QIODevice *device, const QByteArray &format) const
{
if (format == "rgb" || format == "rgba" || format == "bw" || format == "sgi") {
return Capabilities(CanRead | CanWrite);
}
if (!format.isEmpty()) {
return {};
}
if (!device->isOpen()) {
return {};
}
Capabilities cap;
if (device->isReadable() && RGBHandler::canRead(device)) {
cap |= CanRead;
}
if (device->isWritable()) {
cap |= CanWrite;
}
return cap;
}
QImageIOHandler *RGBPlugin::create(QIODevice *device, const QByteArray &format) const
{
QImageIOHandler *handler = new RGBHandler;
handler->setDevice(device);
handler->setFormat(format);
return handler;
}
#include "moc_rgb_p.cpp"