Circle buffer and png cleaning.

src/image/png/PngHeader.cpp

@@ -0,0 +1,89 @@
+#include "PngHeader.h"
+
+#include "ByteUtils.h"
+#include "StringUtils.h"
+#include "CyclicRedundancyChecker.h"
+
+std::string PngHeader::toString() const
+{
+    std::stringstream sstr;
+    sstr << "PngHeader" << "\n";
+    sstr << "width: " << mWidth << "\n";
+    sstr << "height: " << mHeight << "\n";
+    sstr << "bitDepth: " << (int)mBitDepth << "\n";
+    sstr << mPngInfo.toString();
+    return sstr.str();
+}
+
+uint32_t PngHeader::getLength() const
+{
+    return 13;
+}
+
+unsigned char PngHeader::getHighBitCheck() const
+{
+    return 0x89;
+}
+
+std::vector<unsigned char> PngHeader::getSignature() const
+{
+    return {13, 10, 26, 10};
+}
+
+std::string PngHeader::getFileName() const
+{
+    return "PNG";
+}
+
+const std::string& PngHeader::getChunkName() const
+{
+    return "IHDR";
+}
+
+const std::vector<unsigned char>& PngHeader::getData() const
+{
+    return mData;
+}
+
+void PngHeader::updateData()
+{
+    mData.clear();
+    unsigned num_bytes = sizeof(uint32_t);
+
+    for(unsigned idx=0; idx<num_bytes;idx++)
+    {
+        mData.push_back(ByteUtils::getByteN(mWidth, idx));
+    }
+
+    for(unsigned idx=0; idx<num_bytes;idx++)
+    {
+        mData.push_back(ByteUtils::getByteN(mHeight, idx));
+    }
+    mData.push_back(mBitDepth);
+    mData.push_back(static_cast<unsigned char>(mPngInfo.mColorType));
+    mData.push_back(mPngInfo.mCompressionMethod);
+    mData.push_back(mPngInfo.mFilterMethod);
+    mData.push_back(mPngInfo.mInterlaceMethod);
+}
+
+uint32_t PngHeader::getCrc() const
+{
+    CyclicRedundancyChecker crc_check;
+    std::vector<unsigned char> char_data = StringUtils::toBytes(mName);
+    std::copy(mData.begin(), mData.end(), std::back_inserter(char_data));
+
+    auto result = crc_check.doCrc(char_data.data(), char_data.size());
+    return result;
+}
+
+void PngHeader::setPngInfo(const PngInfo& info)
+{
+    mPngInfo = info;
+}
+
+void PngHeader::setImageData(uint32_t width, uint32_t height, unsigned char bitDepth)
+{
+    mWidth = width;
+    mHeight = height;
+    mBitDepth = bitDepth;
+}