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#include <mbgl/util/image.hpp>
#include <mbgl/util/string.hpp>
#include <mbgl/util/premultiply.hpp>
namespace mbgl {
#if !defined(__ANDROID__) && !defined(__APPLE__)
PremultipliedImage decodeWebP(const uint8_t*, size_t);
#endif // !defined(__ANDROID__) && !defined(__APPLE__)
PremultipliedImage decodePNG(const uint8_t*, size_t);
PremultipliedImage decodeJPEG(const uint8_t*, size_t);
PremultipliedImage decodeImage(const std::string& string) {
const auto* data = reinterpret_cast<const uint8_t*>(string.data());
const size_t size = string.size();
#if !defined(__ANDROID__) && !defined(__APPLE__)
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);
}
}
#endif // !defined(__ANDROID__) && !defined(__APPLE__)
if (size >= 4) {
uint32_t magic = (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3];
if (magic == 0x89504E47U) {
return decodePNG(data, size);
}
}
if (size >= 2) {
uint16_t magic = ((data[0] << 8) | data[1]) & 0xffff;
if (magic == 0xFFD8) {
return decodeJPEG(data, size);
}
}
throw std::runtime_error("unsupported image type");
}
} // namespace mbgl
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