jpeginfo: decode basic TIFF tag names

This commit is contained in:
Přemysl Eric Janouch 2021-12-03 14:56:55 +01:00
parent 46c46ac093
commit 06779c6bdd
Signed by: p
GPG Key ID: A0420B94F92B9493

View File

@ -324,6 +324,120 @@ tiffer_next_entry(struct tiffer *self, struct tiffer_entry *entry)
return true;
}
// --- TIFF/Exif/MPF/* tags ----------------------------------------------------
struct tiff_entry {
const char *name;
uint16_t tag;
};
static struct tiff_entry tiff_entries[] = {
{"NewSubfileType", 254},
{"SubfileType", 255},
{"ImageWidth", 256},
{"ImageLength", 257},
{"BitsPerSample", 258},
{"Compression", 259},
{"PhotometricInterpretation", 262},
{"Threshholding", 263},
{"CellWidth", 264},
{"CellLength", 265},
{"FillOrder", 266},
{"DocumentName", 269},
{"ImageDescription", 270},
{"Make", 271},
{"Model", 272},
{"StripOffsets", 273},
{"Orientation", 274},
{"SamplesPerPixel", 277},
{"RowsPerStrip", 278},
{"StripByteCounts", 279},
{"MinSampleValue", 280},
{"MaxSampleValue", 281},
{"XResolution", 282},
{"YResolution", 283},
{"PlanarConfiguration", 284},
{"PageName", 285},
{"XPosition", 286},
{"YPosition", 287},
{"FreeOffsets", 288},
{"FreeByteCounts", 289},
{"GrayResponseUnit", 290},
{"GrayResponseCurve", 291},
{"T4Options", 292},
{"T6Options", 293},
{"ResolutionUnit", 296},
{"PageNumber", 297},
{"TransferFunction", 301},
{"Software", 305},
{"DateTime", 306},
{"Artist", 315},
{"HostComputer", 316},
{"Predictor", 317},
{"WhitePoint", 318},
{"PrimaryChromaticities", 319},
{"ColorMap", 320},
{"HalftoneHints", 321},
{"TileWidth", 322},
{"TileLength", 323},
{"TileOffsets", 324},
{"TileByteCounts", 325},
{"InkSet", 332},
{"InkNames", 333},
{"NumberOfInks", 334},
{"DotRange", 336},
{"TargetPrinter", 337},
{"ExtraSamples", 338},
{"SampleFormat", 339},
{"SMinSampleValue", 340},
{"SMaxSampleValue", 341},
{"TransferRange", 342},
{"JPEGProc", 512},
{"JPEGInterchangeFormat", 513},
{"JPEGInterchangeFormatLngth", 514},
{"JPEGRestartInterval", 515},
{"JPEGLosslessPredictors", 517},
{"JPEGPointTransforms", 518},
{"JPEGQTables", 519},
{"JPEGDCTables", 520},
{"JPEGACTables", 521},
{"YCbCrCoefficients", 529},
{"YCbCrSubSampling", 530},
{"YCbCrPositioning", 531},
{"ReferenceBlackWhite", 532},
{"Copyright", 33432},
{}
};
// Compression
static struct tiff_entry tiff_compression_values[] = {
{"Uncompressed", 1},
{"CCITT 1D", 2},
{"Group 3 Fax", 3},
{"Group 4 Fax", 4},
{"LZW", 5},
{"JPEG", 6},
{"PackBits", 32773},
{}
};
// PhotometricInterpretation
static struct tiff_entry tiff_photometric_interpretation_values[] = {
{"WhiteIsZero", 0},
{"BlackIsZero", 1},
{"RGB", 2},
{"RGB Palette", 3},
{"Transparency mask", 4},
{"CMYK", 5},
{"YCbCr", 6},
{"CIELab", 8},
{}
};
// TODO(p): Insert tags and values from other documentation,
// so far only Appendix A from TIFF 6.0 is present.
// There are still quite a few missing constant names from there.
// --- Analysis ----------------------------------------------------------------
static jv
@ -351,6 +465,17 @@ add_error(jv o, const char *message)
// --- Exif --------------------------------------------------------------------
// TODO(p): Decode more and better.
static jv
process_exif_entry(jv o, const struct tiffer_entry *entry)
{
for (const struct tiff_entry *p = tiff_entries; p->name; p++) {
if (p->tag == entry->tag)
return add_to_subarray(o, "TIFF", jv_string(p->name));
}
return add_to_subarray(o, "TIFF", jv_number(entry->tag));
}
static jv
parse_exif(jv o, const uint8_t *p, size_t len)
{
@ -358,11 +483,11 @@ parse_exif(jv o, const uint8_t *p, size_t len)
if (!tiffer_init(&T, p, len))
return add_warning(o, "invalid Exif");
// TODO(p): Decode more and better.
// TODO(p): Turn this into an array of objects indexed by tag name.
struct tiffer_entry entry;
while (tiffer_next_ifd(&T)) {
while (tiffer_next_entry(&T, &entry)) {
o = add_to_subarray(o, "TIFF", jv_number(entry.tag));
o = process_exif_entry(o, &entry);
}
}
return o;