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#include <mbgl/util/image.hpp>
#include <QBuffer>
#include <QByteArray>
#include <QImage>
namespace mbgl {
std::string encodePNG(const PremultipliedImage& pre) {
QImage image(pre.data.get(), pre.width, pre.height,
QImage::Format_ARGB32_Premultiplied);
QByteArray array;
QBuffer buffer(&array);
buffer.open(QIODevice::WriteOnly);
image.rgbSwapped().save(&buffer, "PNG");
return std::string(array.constData(), array.size());
}
#if !defined(QT_IMAGE_DECODERS)
PremultipliedImage decodeJPEG(const uint8_t*, size_t);
PremultipliedImage decodeWebP(const uint8_t*, size_t);
#endif
PremultipliedImage decodeImage(const std::string& string) {
const uint8_t* data = reinterpret_cast<const uint8_t*>(string.data());
const size_t size = string.size();
#if !defined(QT_IMAGE_DECODERS)
if (size >= 12) {
uint32_t riff_magic = (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3];
uint32_t webp_magic = (data[8] << 24) | (data[9] << 16) | (data[10] << 8) | data[11];
if (riff_magic == 0x52494646 && webp_magic == 0x57454250) {
return decodeWebP(data, size);
}
}
if (size >= 2) {
uint16_t magic = ((data[0] << 8) | data[1]) & 0xffff;
if (magic == 0xFFD8) {
return decodeJPEG(data, size);
}
}
#endif
QImage image =
QImage::fromData(data, size)
.rgbSwapped()
.convertToFormat(QImage::Format_ARGB32_Premultiplied);
if (image.isNull()) {
throw std::runtime_error("Unsupported image type");
}
auto img = std::make_unique<uint8_t[]>(image.byteCount());
memcpy(img.get(), image.constBits(), image.byteCount());
return { static_cast<uint16_t>(image.width()), static_cast<uint16_t>(image.height()),
std::move(img) };
}
}
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