From d81e26d360e649c37a1b859331c3348c7b9089ec Mon Sep 17 00:00:00 2001 From: Paul Elder Date: Thu, 21 Jan 2021 17:16:42 +0900 Subject: android: jpeg: exif: Expand setString to support different encodings GPSProcessingMethod and UserComment in EXIF tags can be in UTF-16. Expand setString to take an encoding when the field type is undefined. Update callers accordingly. Signed-off-by: Paul Elder Reviewed-by: Laurent Pinchart Reviewed-by: Jacopo Mondi --- src/android/jpeg/exif.cpp | 77 +++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 74 insertions(+), 3 deletions(-) (limited to 'src/android/jpeg/exif.cpp') diff --git a/src/android/jpeg/exif.cpp b/src/android/jpeg/exif.cpp index 33b3fa7f..89343323 100644 --- a/src/android/jpeg/exif.cpp +++ b/src/android/jpeg/exif.cpp @@ -7,6 +7,9 @@ #include "exif.h" +#include +#include + #include "libcamera/internal/log.h" #include "libcamera/internal/utils.h" @@ -178,11 +181,18 @@ void Exif::setRational(ExifIfd ifd, ExifTag tag, ExifRational item) exif_entry_unref(entry); } -void Exif::setString(ExifIfd ifd, ExifTag tag, ExifFormat format, const std::string &item) +static const std::map> stringEncodingCodes = { + { Exif::ASCII, { 0x41, 0x53, 0x43, 0x49, 0x49, 0x00, 0x00, 0x00 } }, + { Exif::Unicode, { 0x55, 0x4e, 0x49, 0x43, 0x4f, 0x44, 0x45, 0x00 } }, +}; + +void Exif::setString(ExifIfd ifd, ExifTag tag, ExifFormat format, + const std::string &item, StringEncoding encoding) { std::string ascii; size_t length; const char *str; + std::vector buf; if (format == EXIF_FORMAT_ASCII) { ascii = utils::toAscii(item); @@ -191,13 +201,46 @@ void Exif::setString(ExifIfd ifd, ExifTag tag, ExifFormat format, const std::str /* Pad 1 extra byte to null-terminate the ASCII string. */ length = ascii.length() + 1; } else { - str = item.c_str(); + std::u16string u16str; + + auto encodingString = stringEncodingCodes.find(encoding); + if (encodingString != stringEncodingCodes.end()) { + buf = { + encodingString->second.begin(), + encodingString->second.end() + }; + } + + switch (encoding) { + case Unicode: + u16str = utf8ToUtf16(item); + + buf.resize(8 + u16str.size() * 2); + for (size_t i = 0; i < u16str.size(); i++) { + if (order_ == EXIF_BYTE_ORDER_INTEL) { + buf[8 + 2 * i] = u16str[i] & 0xff; + buf[8 + 2 * i + 1] = (u16str[i] >> 8) & 0xff; + } else { + buf[8 + 2 * i] = (u16str[i] >> 8) & 0xff; + buf[8 + 2 * i + 1] = u16str[i] & 0xff; + } + } + + break; + + case ASCII: + case NoEncoding: + buf.insert(buf.end(), item.begin(), item.end()); + break; + } + + str = reinterpret_cast(buf.data()); /* * Strings stored in different formats (EXIF_FORMAT_UNDEFINED) * are not null-terminated. */ - length = item.length(); + length = buf.size(); } ExifEntry *entry = createEntry(ifd, tag, format, length, length); @@ -290,6 +333,34 @@ void Exif::setThumbnail(Span thumbnail, setShort(EXIF_IFD_0, EXIF_TAG_COMPRESSION, compression); } +/** + * \brief Convert UTF-8 string to UTF-16 string + * \param[in] str String to convert + * + * \return \a str in UTF-16 + */ +std::u16string Exif::utf8ToUtf16(const std::string &str) +{ + mbstate_t state{}; + char16_t c16; + const char *ptr = str.data(); + const char *end = ptr + str.size(); + + std::u16string ret; + while (size_t rc = mbrtoc16(&c16, ptr, end - ptr + 1, &state)) { + if (rc == static_cast(-2) || + rc == static_cast(-1)) + break; + + ret.push_back(c16); + + if (rc > 0) + ptr += rc; + } + + return ret; +} + [[nodiscard]] int Exif::generate() { if (exifData_) { -- cgit v1.2.1