RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-27 07:47:35 +00:00
Code Issues Activity Actions

LibGfx+icc: Print if profile id is valid

Browse source
This commit is contained in:
Nico Weber 2023-01-04 15:34:25 -05:00 • committed by Andreas Kling
parent fafacbb87b
commit 68f678f566
3 changed files with 34 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

24
Userland/Libraries/LibGfx/ICCProfile.cpp
View file

@ -248,6 +248,9 @@ Optional<Crypto::Hash::MD5::DigestType> parse_profile_id(ICCHeader const& header
Crypto::Hash::MD5::DigestType md5;
static_assert(sizeof(md5.data) == sizeof(header.profile_md5));
memcpy(md5.data, header.profile_md5, sizeof(md5.data));
// FIXME: Consider comparing read id with compute_id() result and failing if they aren't equal.
return md5;
}
}
@ -386,4 +389,25 @@ ErrorOr<NonnullRefPtr<Profile>> Profile::try_load_from_externally_owned_memory(R
return profile;
}
Crypto::Hash::MD5::DigestType Profile::compute_id(ReadonlyBytes bytes)
{
// ICC v4, 7.2.18 Profile ID field
// The Profile ID shall be calculated using the MD5 fingerprinting method as defined in Internet RFC 1321.
// The entire profile, whose length is given by the size field in the header,
// with the profile flags field (bytes 44 to 47, see 7.2.11),
// rendering intent field (bytes 64 to 67, see 7.2.15),
// and profile ID field (bytes 84 to 99) in the profile header
// temporarily set to zeros (00h), shall be used to calculate the ID.
const u8 zero[16] = {};
Crypto::Hash::MD5 md5;
md5.update(bytes.slice(0, 44));
md5.update(ReadonlyBytes { zero, 4 }); // profile flags field
md5.update(bytes.slice(48, 64 - 48));
md5.update(ReadonlyBytes { zero, 4 }); // rendering intent field
md5.update(bytes.slice(68, 84 - 68));
md5.update(ReadonlyBytes { zero, 16 }); // profile ID field
md5.update(bytes.slice(100));
return md5.digest();
}
}

2
Userland/Libraries/LibGfx/ICCProfile.h
View file

@ -139,6 +139,8 @@ public:
XYZ const& pcs_illuminant() const { return m_pcs_illuminant; }
Optional<Crypto::Hash::MD5::DigestType> const& id() const { return m_id; }
static Crypto::Hash::MD5::DigestType compute_id(ReadonlyBytes);
private:
Version m_version;
DeviceClass m_device_class;

9
Userland/Utilities/icc.cpp
View file

@ -40,9 +40,14 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
outln("pcs illuminant: {}", profile->pcs_illuminant());
out("id: ");
if (auto id = profile->id(); id.has_value())
outln("{}", *id);
if (auto id = profile->id(); id.has_value()) {
out("{}", *id);
auto computed = Gfx::ICC::Profile::compute_id(icc_file->bytes());
if (*id == computed)
outln(" (valid)");
else
outln(" (invalid! valid would be {})", computed);
} else
outln("(not set)");
return 0;