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#include <qpdf/SF_FlateLzwDecode.hh>
#include <qpdf/Pl_Flate.hh>
#include <qpdf/Pl_LZWDecoder.hh>
#include <qpdf/Pl_PNGFilter.hh>
#include <qpdf/Pl_TIFFPredictor.hh>
#include <qpdf/QIntC.hh>
#include <qpdf/QTC.hh>
SF_FlateLzwDecode::SF_FlateLzwDecode(bool lzw) :
lzw(lzw),
// Initialize values to their defaults as per the PDF spec
predictor(1),
columns(0),
colors(1),
bits_per_component(8),
early_code_change(true)
{
}
bool
SF_FlateLzwDecode::setDecodeParms(QPDFObjectHandle decode_parms)
{
if (decode_parms.isNull()) {
return true;
}
bool filterable = true;
std::set<std::string> keys = decode_parms.getKeys();
for (auto const& key: keys) {
QPDFObjectHandle value = decode_parms.getKey(key);
if (key == "/Predictor") {
if (value.isInteger()) {
this->predictor = value.getIntValueAsInt();
if (!((this->predictor == 1) || (this->predictor == 2) ||
((this->predictor >= 10) && (this->predictor <= 15)))) {
filterable = false;
}
} else {
filterable = false;
}
} else if (
(key == "/Columns") || (key == "/Colors") ||
(key == "/BitsPerComponent")) {
if (value.isInteger()) {
int val = value.getIntValueAsInt();
if (key == "/Columns") {
this->columns = val;
} else if (key == "/Colors") {
this->colors = val;
} else if (key == "/BitsPerComponent") {
this->bits_per_component = val;
}
} else {
filterable = false;
}
} else if (lzw && (key == "/EarlyChange")) {
if (value.isInteger()) {
int earlychange = value.getIntValueAsInt();
this->early_code_change = (earlychange == 1);
if (!((earlychange == 0) || (earlychange == 1))) {
filterable = false;
}
} else {
filterable = false;
}
}
}
if ((this->predictor > 1) && (this->columns == 0)) {
filterable = false;
}
return filterable;
}
Pipeline*
SF_FlateLzwDecode::getDecodePipeline(Pipeline* next)
{
std::shared_ptr<Pipeline> pipeline;
if ((this->predictor >= 10) && (this->predictor <= 15)) {
QTC::TC("qpdf", "SF_FlateLzwDecode PNG filter");
pipeline = std::make_shared<Pl_PNGFilter>(
"png decode",
next,
Pl_PNGFilter::a_decode,
QIntC::to_uint(this->columns),
QIntC::to_uint(this->colors),
QIntC::to_uint(this->bits_per_component));
this->pipelines.push_back(pipeline);
next = pipeline.get();
} else if (this->predictor == 2) {
QTC::TC("qpdf", "SF_FlateLzwDecode TIFF predictor");
pipeline = std::make_shared<Pl_TIFFPredictor>(
"tiff decode",
next,
Pl_TIFFPredictor::a_decode,
QIntC::to_uint(this->columns),
QIntC::to_uint(this->colors),
QIntC::to_uint(this->bits_per_component));
this->pipelines.push_back(pipeline);
next = pipeline.get();
}
if (lzw) {
pipeline = std::make_shared<Pl_LZWDecoder>(
"lzw decode", next, early_code_change);
} else {
pipeline = std::make_shared<Pl_Flate>(
"stream inflate", next, Pl_Flate::a_inflate);
}
this->pipelines.push_back(pipeline);
return pipeline.get();
}
std::shared_ptr<QPDFStreamFilter>
SF_FlateLzwDecode::flate_factory()
{
return std::make_shared<SF_FlateLzwDecode>(false);
}
std::shared_ptr<QPDFStreamFilter>
SF_FlateLzwDecode::lzw_factory()
{
return std::make_shared<SF_FlateLzwDecode>(true);
}
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