From bb4b895cb5938712bd09fbd2b5f49bea811d7551 Mon Sep 17 00:00:00 2001 From: Přemysl Eric Janouch Date: Tue, 23 May 2023 02:09:15 +0200 Subject: Extract some full-size raw previews without LibRaw Not all image/x-nikon-nef will work like this, so don't claim their MIME type. --- fiv-io.c | 394 +++++++++++++++++++++++++++++++++++++++++++++++--------- tiff-tables.awk | 20 ++- tiffer.h | 340 ++++++++++++++++++++++++++++++++++++++++++++++++ tools/info.h | 363 ++++----------------------------------------------- 4 files changed, 716 insertions(+), 401 deletions(-) create mode 100644 tiffer.h diff --git a/fiv-io.c b/fiv-io.c index c4c61f4..7659fa8 100644 --- a/fiv-io.c +++ b/fiv-io.c @@ -41,6 +41,10 @@ #include #endif // HAVE_LCMS2 +#define TIFF_TABLES_CONSTANTS_ONLY +#include "tiff-tables.h" +#include "tiffer.h" + #ifdef HAVE_LIBRAW #include #if LIBRAW_VERSION >= LIBRAW_MAKE_VERSION(0, 21, 0) @@ -1141,32 +1145,28 @@ fail: // --- JPEG -------------------------------------------------------------------- -static GBytes * -parse_jpeg_metadata(cairo_surface_t *surface, const char *data, gsize len) +struct jpeg_metadata { + GByteArray *exif; ///< Exif buffer or NULL + GByteArray *icc; ///< ICC profile buffer or NULL + int width; ///< Image width + int height; ///< Image height +}; + +static void +parse_jpeg_metadata(const char *data, size_t len, struct jpeg_metadata *meta) { // Because the JPEG file format is simple, just do it manually. // See: https://www.w3.org/Graphics/JPEG/itu-t81.pdf enum { - APP0 = 0xE0, - APP1, - APP2, - RST0 = 0xD0, - RST1, - RST2, - RST3, - RST4, - RST5, - RST6, - RST7, - SOI = 0xD8, - EOI = 0xD9, - SOS = 0xDA, TEM = 0x01, + SOF0 = 0xC0, SOF1, SOF2, SOF3, DHT, SOF5, SOF6, SOF7, + JPG, SOF9, SOF10, SOF11, DAC, SOF13, SOF14, SOF15, + RST0, RST1, RST2, RST3, RST4, RST5, RST6, RST7, + SOI, EOI, SOS, DQT, DNL, DRI, DHP, EXP, + APP0, APP1, APP2, APP3, APP4, APP5, APP6, APP7, }; - GByteArray *exif = g_byte_array_new(), *icc = g_byte_array_new(); int icc_sequence = 0, icc_done = FALSE; - const guint8 *p = (const guint8 *) data, *end = p + len; while (p + 3 < end && *p++ == 0xFF && *p != SOS && *p != EOI) { // The previous byte is a fill byte, restart. @@ -1195,49 +1195,76 @@ parse_jpeg_metadata(cairo_surface_t *surface, const char *data, gsize len) if (G_UNLIKELY((p += length) > end)) break; + switch (marker) { + case SOF0: + case SOF1: + case SOF2: + case SOF3: + case SOF5: + case SOF6: + case SOF7: + case SOF9: + case SOF10: + case SOF11: + case SOF13: + case SOF14: + case SOF15: + if (length >= 5) { + meta->width = (payload[3] << 8) + payload[4]; + meta->height = (payload[1] << 8) + payload[2]; + } + } + // https://www.cipa.jp/std/documents/e/DC-008-2012_E.pdf 4.7.2 // Adobe XMP Specification Part 3: Storage in Files, 2020/1, 1.1.3 // Not checking the padding byte is intentional. - if (marker == APP1 && p - payload >= 6 && - !memcmp(payload, "Exif\0", 5) && !exif->len) { + // XXX: Thumbnails may in practice overflow into follow-up segments. + if (meta->exif && marker == APP1 && p - payload >= 6 && + !memcmp(payload, "Exif\0", 5) && !meta->exif->len) { payload += 6; - g_byte_array_append(exif, payload, p - payload); + g_byte_array_append(meta->exif, payload, p - payload); } // https://www.color.org/specification/ICC1v43_2010-12.pdf B.4 - if (marker == APP2 && p - payload >= 14 && + if (meta->icc && marker == APP2 && p - payload >= 14 && !memcmp(payload, "ICC_PROFILE\0", 12) && !icc_done && payload[12] == ++icc_sequence && payload[13] >= payload[12]) { payload += 14; - g_byte_array_append(icc, payload, p - payload); + g_byte_array_append(meta->icc, payload, p - payload); icc_done = payload[-1] == icc_sequence; } // TODO(p): Extract the main XMP segment. } - if (exif->len) + if (meta->icc && !icc_done) + g_byte_array_set_size(meta->icc, 0); +} + +static void +load_jpeg_finalize(cairo_surface_t *surface, bool cmyk, + FivIoProfile destination, const char *data, size_t len) +{ + struct jpeg_metadata meta = { + .exif = g_byte_array_new(), .icc = g_byte_array_new()}; + + parse_jpeg_metadata(data, len, &meta); + + if (meta.exif->len) cairo_surface_set_user_data(surface, &fiv_io_key_exif, - g_byte_array_free_to_bytes(exif), + g_byte_array_free_to_bytes(meta.exif), (cairo_destroy_func_t) g_bytes_unref); else - g_byte_array_free(exif, TRUE); + g_byte_array_free(meta.exif, TRUE); GBytes *icc_profile = NULL; - if (icc_done) + if (meta.icc->len) cairo_surface_set_user_data(surface, &fiv_io_key_icc, - (icc_profile = g_byte_array_free_to_bytes(icc)), + (icc_profile = g_byte_array_free_to_bytes(meta.icc)), (cairo_destroy_func_t) g_bytes_unref); else - g_byte_array_free(icc, TRUE); - return icc_profile; -} + g_byte_array_free(meta.icc, TRUE); -static void -load_jpeg_finalize(cairo_surface_t *surface, bool cmyk, - FivIoProfile destination, const char *data, size_t len) -{ - GBytes *icc_profile = parse_jpeg_metadata(surface, data, len); FivIoProfile source = NULL; if (icc_profile) source = fiv_io_profile_new( @@ -1700,6 +1727,269 @@ fail: return result; } +// --- TIFF/EP + DNG ----------------------------------------------------------- +// In Nikon NEF files, which claim to be TIFF/EP-compatible, IFD0 is a tiny +// uncompressed thumbnail with SubIFDs that, aside from raw sensor data, +// typically contain a nearly full-size JPEG preview. +// +// LibRaw takes too long a time to render something that will never be as good +// as the large preview, and libtiff can only read the horrible IFD0 thumbnail. +// (TIFFSetSubDirectory() requires an ImageLength tag that's missing from JPEG +// SubIFDs, and TIFFReadCustomDirectory() takes a privately defined struct that +// may not be omitted.) +// +// While LibRaw since 0.21.0 provides an API that would allow us to extract +// the JPEG, a little bit of custom processing won't hurt either. + +static bool +tiffer_find(const struct tiffer *self, uint16_t tag, struct tiffer_entry *entry) +{ + // Note that we could employ binary search, because tags must be ordered: + // - TIFF 6.0: Sort Order + // - ISO/DIS 12234-2: 4.1.2, 5.1 + // - CIPA DC-007-2009 (Multi-Picture Format): 5.2.3., 5.2.4. + // - CIPA DC-008-2019 (Exif 2.32): 4.6.2. + // However, it doesn't seem to warrant the ugly code. + struct tiffer T = *self; + while (tiffer_next_entry(&T, entry)) { + if (entry->tag == tag) + return true; + } + *entry = (struct tiffer_entry) {}; + return false; +} + +static bool +tiffer_find_integer(const struct tiffer *self, uint16_t tag, int64_t *i) +{ + struct tiffer_entry entry = {}; + return tiffer_find(self, tag, &entry) && tiffer_integer(self, &entry, i); +} + +// In case of failure, an entry with a zero "remaining_count" is returned. +static struct tiffer_entry +tiff_ep_subifds_init(const struct tiffer *T) +{ + struct tiffer_entry entry = {}; + (void) tiffer_find(T, TIFF_SubIFDs, &entry); + return entry; +} + +static bool +tiff_ep_subifds_next( + const struct tiffer *T, struct tiffer_entry *subifds, struct tiffer *subT) +{ + // XXX: Except for a zero "remaining_count", all conditions are errors, + // and should perhaps be reported. + int64_t offset = 0; + if (!tiffer_integer(T, subifds, &offset) || + offset < 0 || offset > UINT32_MAX || !tiffer_subifd(T, offset, subT)) + return false; + + (void) tiffer_next_value(subifds); + return true; +} + +static bool +tiff_ep_find_main(const struct tiffer *T, struct tiffer *outputT) +{ + // This is a mandatory field. + int64_t type = 0; + if (!tiffer_find_integer(T, TIFF_NewSubfileType, &type)) + return false; + + // This is the main image. + // (See DNG rather than ISO/DIS 12234-2 for values.) + if (type == 0) { + *outputT = *T; + return true; + } + + struct tiffer_entry subifds = tiff_ep_subifds_init(T); + struct tiffer subT = {}; + while (tiff_ep_subifds_next(T, &subifds, &subT)) + if (tiff_ep_find_main(&subT, outputT)) + return true; + return false; +} + +struct tiff_ep_jpeg { + const uint8_t *jpeg; ///< JPEG data stream + size_t jpeg_length; ///< JPEG data stream length + int64_t pixels; ///< Number of pixels in the JPEG +}; + +static void +tiff_ep_find_jpeg_evaluate(const struct tiffer *T, struct tiff_ep_jpeg *out) +{ + // This is a mandatory field. + int64_t compression = 0; + if (!tiffer_find_integer(T, TIFF_Compression, &compression)) + return; + + uint16_t tag_pointer = 0, tag_length = 0; + switch (compression) { + // This is how Exif specifies it, which doesn't follow TIFF 6.0. + case TIFF_Compression_JPEG: + tag_pointer = TIFF_JPEGInterchangeFormat; + tag_length = TIFF_JPEGInterchangeFormatLength; + break; + // Theoretically, there may be more strips, but this is not expected. + case TIFF_Compression_JPEGDatastream: + tag_pointer = TIFF_StripOffsets; + tag_length = TIFF_StripByteCounts; + break; + default: + return; + } + + int64_t ipointer = 0, ilength = 0; + if (!tiffer_find_integer(T, tag_pointer, &ipointer) || + !tiffer_find_integer(T, tag_length, &ilength) || + ipointer <= 0 || ilength <= 0 || + (uint64_t) ilength > SIZE_MAX || + ipointer + ilength > (T->end - T->begin)) + return; + + // Note that to get the largest JPEG, + // we don't need to descend into Exif thumbnails. + // TODO(p): Consider DNG 1.2.0.0 PreviewColorSpace. + // But first, try to find some real-world files with it. + const uint8_t *jpeg = T->begin + ipointer; + size_t jpeg_length = ilength; + + struct jpeg_metadata meta = {}; + parse_jpeg_metadata((const char *) jpeg, jpeg_length, &meta); + int64_t pixels = meta.width * meta.height; + if (pixels > out->pixels) { + out->jpeg = jpeg; + out->jpeg_length = jpeg_length; + out->pixels = pixels; + } +} + +static bool +tiff_ep_find_jpeg(const struct tiffer *T, struct tiff_ep_jpeg *out) +{ + // This is a mandatory field. + int64_t type = 0; + if (!tiffer_find_integer(T, TIFF_NewSubfileType, &type)) + return false; + + // This is a thumbnail of the main image. + // (See DNG rather than ISO/DIS 12234-2 for values.) + if (type == 1) + tiff_ep_find_jpeg_evaluate(T, out); + + struct tiffer_entry subifds = tiff_ep_subifds_init(T); + struct tiffer subT = {}; + while (tiff_ep_subifds_next(T, &subifds, &subT)) + if (!tiff_ep_find_jpeg(&subT, out)) + return false; + return true; +} + +static cairo_surface_t * +load_tiff_ep( + const struct tiffer *T, const FivIoOpenContext *ctx, GError **error) +{ + // ISO/DIS 12234-2 is a fuck-up that says this should be in "IFD0", + // but it might have intended to say "all top-level IFDs". + // The DNG specification shares the same problem. + // + // In any case, chained TIFFs are relatively rare. + struct tiffer_entry entry = {}; + bool is_tiffep = tiffer_find(T, TIFF_TIFF_EPStandardID, &entry) && + entry.type == BYTE && entry.remaining_count == 4 && + entry.p[0] == 1 && !entry.p[1] && !entry.p[2] && !entry.p[3]; + + // Apple ProRAW, e.g., does not claim TIFF/EP compatibility, + // but we should still be able to make sense of it. + bool is_supported_dng = tiffer_find(T, TIFF_DNGBackwardVersion, &entry) && + entry.type == BYTE && entry.remaining_count == 4 && + entry.p[0] == 1 && entry.p[1] <= 6 && !entry.p[2] && !entry.p[3]; + if (!is_tiffep && !is_supported_dng) { + set_error(error, "not a supported TIFF/EP or DNG image"); + return NULL; + } + + struct tiffer fullT = {}; + if (!tiff_ep_find_main(T, &fullT)) { + set_error(error, "could not find a main image"); + return NULL; + } + + int64_t width = 0, height = 0; + if (!tiffer_find_integer(&fullT, TIFF_ImageWidth, &width) || + !tiffer_find_integer(&fullT, TIFF_ImageLength, &height) || + width <= 0 || height <= 0) { + set_error(error, "missing or invalid main image dimensions"); + return NULL; + } + + struct tiff_ep_jpeg out = {}; + if (!tiff_ep_find_jpeg(T, &out)) { + set_error(error, "error looking for a full-size JPEG preview"); + return NULL; + } + + // Nikon NEFs seem to generally have a preview above 99 percent, + // (though some of them may not even reach 50 percent). + // Be a bit more generous than that with our crop tolerance. + // TODO(p): Also take into account DNG DefaultCropSize, if present. + if (out.pixels / ((double) width * height) < 0.95) { + set_error(error, "could not find a large enough JPEG preview"); + return NULL; + } + + cairo_surface_t *surface = open_libjpeg_turbo( + (const char *) out.jpeg, out.jpeg_length, ctx, error); + if (!surface) + return NULL; + + // Note that Exif may override this later in fiv_io_open_from_data(). + // TODO(p): Try to use the Orientation field nearest to the target IFD. + // IFD0 just happens to be fine for Nikon NEF. + int64_t orientation = 0; + if (tiffer_find_integer(T, TIFF_Orientation, &orientation) && + orientation >= 1 && orientation <= 8) { + cairo_surface_set_user_data(surface, &fiv_io_key_orientation, + (void *) (uintptr_t) orientation, NULL); + } + return surface; +} + +static cairo_surface_t * +open_tiff_ep( + const char *data, gsize len, const FivIoOpenContext *ctx, GError **error) +{ + // -Wunused-function, we might want to give this its own compile unit. + (void) tiffer_real; + + struct tiffer T = {}; + if (!tiffer_init(&T, (const uint8_t *) data, len)) { + set_error(error, "not a TIFF file"); + return NULL; + } + + cairo_surface_t *result = NULL, *result_tail = NULL; + while (tiffer_next_ifd(&T)) { + if (!try_append_page( + load_tiff_ep(&T, ctx, error), &result, &result_tail)) { + g_clear_pointer(&result, cairo_surface_destroy); + return NULL; + } + if (ctx->first_frame_only) + break; + + // TODO(p): Try to adjust tiffer so that this isn't necessary. + struct tiffer_entry dummy = {}; + while (tiffer_next_entry(&T, &dummy)) + ; + } + return result; +} + // --- Optional dependencies --------------------------------------------------- #ifdef HAVE_LIBRAW // --------------------------------------------------------- @@ -2590,30 +2880,6 @@ open_libtiff( if (!tiff) goto fail; - // In Nikon NEF files, IFD0 is a tiny uncompressed thumbnail with SubIFDs-- - // two of them JPEGs, the remaining one is raw. libtiff cannot read either - // of those better versions. - // - // TODO(p): If NewSubfileType is ReducedImage, and it has SubIFDs compressed - // as old JPEG (6), decode JPEGInterchangeFormat/JPEGInterchangeFormatLength - // with libjpeg-turbo and insert them as the starting pages. - // - // This is not possible with libtiff directly, because TIFFSetSubDirectory() - // requires an ImageLength tag that's missing, and TIFFReadCustomDirectory() - // takes a privately defined struct that cannot be omitted. - // - // TODO(p): Samsung Android DNGs also claim to be TIFF/EP, but use a smaller - // uncompressed YCbCr image. Apple ProRAW uses the new JPEG Compression (7), - // with a weird Orientation. It also uses that value for its raw data. - uint32_t subtype = 0; - uint16_t subifd_count = 0; - const uint64_t *subifd_offsets = NULL; - if (TIFFGetField(tiff, TIFFTAG_SUBFILETYPE, &subtype) && - (subtype & FILETYPE_REDUCEDIMAGE) && - TIFFGetField(tiff, TIFFTAG_SUBIFD, &subifd_count, &subifd_offsets) && - subifd_count > 0 && subifd_offsets) { - } - do { // We inform about unsupported directories, but do not fail on them. GError *err = NULL; @@ -2824,6 +3090,14 @@ fiv_io_open_from_data( surface = open_libwebp(data, len, ctx, error); break; default: + // Try to extract full-size previews from TIFF/EP-compatible raws. + if ((surface = open_tiff_ep(data, len, ctx, error))) + break; + if (error) { + g_debug("%s", (*error)->message); + g_clear_error(error); + } + #ifdef HAVE_LIBRAW // --------------------------------------------------------- if ((surface = open_libraw(data, len, ctx, error))) break; diff --git a/tiff-tables.awk b/tiff-tables.awk index 2d93c36..29b462b 100755 --- a/tiff-tables.awk +++ b/tiff-tables.awk @@ -2,6 +2,22 @@ BEGIN { FS = ", *" print "// Generated by tiff-tables.awk. DO NOT MODIFY." + print "" + print "#ifndef TIFF_TABLES_CONSTANTS_ONLY" + print "#include " + print "#include " + print "" + print "struct tiff_value {" + print "\tconst char *name;" + print "\tuint16_t value;" + print "};" + print "" + print "struct tiff_entry {" + print "\tconst char *name;" + print "\tuint16_t tag;" + print "\tstruct tiff_value *values;" + print "};" + print "#endif" } { @@ -55,8 +71,10 @@ function flushvalues() { function flushsection() { if (section) { flushvalues() - print "};\n\n" allvalues "static struct tiff_entry " \ + print "};\n\n" allvalues "#ifndef TIFF_TABLES_CONSTANTS_ONLY" + print "static struct tiff_entry " \ sectionsnakecase "_entries[] = {" fields "\n\t{}\n};" + print "#endif" } } diff --git a/tiffer.h b/tiffer.h new file mode 100644 index 0000000..b4cbc5d --- /dev/null +++ b/tiffer.h @@ -0,0 +1,340 @@ +// +// tiffer.h: TIFF reading utilities +// +// Copyright (c) 2021 - 2023, Přemysl Eric Janouch +// +// Permission to use, copy, modify, and/or distribute this software for any +// purpose with or without fee is hereby granted. +// +// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY +// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION +// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN +// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +// + +#include +#include +#include + +// --- Utilities --------------------------------------------------------------- + +static uint64_t +tiffer_u64be(const uint8_t *p) +{ + return (uint64_t) p[0] << 56 | (uint64_t) p[1] << 48 | + (uint64_t) p[2] << 40 | (uint64_t) p[3] << 32 | + (uint64_t) p[4] << 24 | p[5] << 16 | p[6] << 8 | p[7]; +} + +static uint32_t +tiffer_u32be(const uint8_t *p) +{ + return (uint32_t) p[0] << 24 | p[1] << 16 | p[2] << 8 | p[3]; +} + +static uint16_t +tiffer_u16be(const uint8_t *p) +{ + return (uint16_t) p[0] << 8 | p[1]; +} + +static uint64_t +tiffer_u64le(const uint8_t *p) +{ + return (uint64_t) p[7] << 56 | (uint64_t) p[6] << 48 | + (uint64_t) p[5] << 40 | (uint64_t) p[4] << 32 | + (uint64_t) p[3] << 24 | p[2] << 16 | p[1] << 8 | p[0]; +} + +static uint32_t +tiffer_u32le(const uint8_t *p) +{ + return (uint32_t) p[3] << 24 | p[2] << 16 | p[1] << 8 | p[0]; +} + +static uint16_t +tiffer_u16le(const uint8_t *p) +{ + return (uint16_t) p[1] << 8 | p[0]; +} + +// --- TIFF -------------------------------------------------------------------- +// libtiff is a mess, and the format is not particularly complicated. +// Exiv2 is senselessly copylefted, and cannot do much. +// libexif is only marginally better. +// ExifTool is too user-oriented. + +struct un { + uint64_t (*u64) (const uint8_t *); + uint32_t (*u32) (const uint8_t *); + uint16_t (*u16) (const uint8_t *); +}; + +static struct un tiffer_unbe = {tiffer_u64be, tiffer_u32be, tiffer_u16be}; +static struct un tiffer_unle = {tiffer_u64le, tiffer_u32le, tiffer_u16le}; + +struct tiffer { + struct un *un; + const uint8_t *begin, *p, *end; + uint16_t remaining_fields; +}; + +static bool +tiffer_u32(struct tiffer *self, uint32_t *u) +{ + if (self->p < self->begin || self->p + 4 > self->end) + return false; + + *u = self->un->u32(self->p); + self->p += 4; + return true; +} + +static bool +tiffer_u16(struct tiffer *self, uint16_t *u) +{ + if (self->p < self->begin || self->p + 2 > self->end) + return false; + + *u = self->un->u16(self->p); + self->p += 2; + return true; +} + +// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + +static bool +tiffer_init(struct tiffer *self, const uint8_t *tiff, size_t len) +{ + self->un = NULL; + self->begin = self->p = tiff; + self->end = tiff + len; + self->remaining_fields = 0; + + const uint8_t + le[4] = {'I', 'I', 42, 0}, + be[4] = {'M', 'M', 0, 42}; + + if (tiff + 8 > self->end) + return false; + else if (!memcmp(tiff, le, sizeof le)) + self->un = &tiffer_unle; + else if (!memcmp(tiff, be, sizeof be)) + self->un = &tiffer_unbe; + else + return false; + + self->p = tiff + 4; + // The first IFD needs to be read by caller explicitly, + // even though it's required to be present by TIFF 6.0. + return true; +} + +/// Read the next IFD in a sequence. +static bool +tiffer_next_ifd(struct tiffer *self) +{ + // All fields from any previous IFD need to be read first. + if (self->remaining_fields) + return false; + + uint32_t ifd_offset = 0; + if (!tiffer_u32(self, &ifd_offset)) + return false; + + // There is nothing more to read, this chain has terminated. + if (!ifd_offset) + return false; + + // Note that TIFF 6.0 requires there to be at least one entry, + // but there is no need for us to check it. + self->p = self->begin + ifd_offset; + return tiffer_u16(self, &self->remaining_fields); +} + +/// Initialize a derived TIFF reader for a subIFD at the given location. +static bool +tiffer_subifd( + const struct tiffer *self, uint32_t offset, struct tiffer *subreader) +{ + *subreader = *self; + subreader->p = subreader->begin + offset; + return tiffer_u16(subreader, &subreader->remaining_fields); +} + +enum tiffer_type { + BYTE = 1, ASCII, SHORT, LONG, RATIONAL, + SBYTE, UNDEFINED, SSHORT, SLONG, SRATIONAL, FLOAT, DOUBLE, + IFD // This last type from TIFF Technical Note 1 isn't really used much. +}; + +static size_t +tiffer_value_size(enum tiffer_type type) +{ + switch (type) { + case BYTE: + case SBYTE: + case ASCII: + case UNDEFINED: + return 1; + case SHORT: + case SSHORT: + return 2; + case LONG: + case SLONG: + case FLOAT: + case IFD: + return 4; + case RATIONAL: + case SRATIONAL: + case DOUBLE: + return 8; + default: + return 0; + } +} + +/// A lean iterator for values within entries. +struct tiffer_entry { + uint16_t tag; + enum tiffer_type type; + // For {S,}BYTE, ASCII, UNDEFINED, use these fields directly. + const uint8_t *p; + uint32_t remaining_count; +}; + +static bool +tiffer_next_value(struct tiffer_entry *entry) +{ + if (!entry->remaining_count) + return false; + + entry->p += tiffer_value_size(entry->type); + entry->remaining_count--; + return true; +} + +static bool +tiffer_integer( + const struct tiffer *self, const struct tiffer_entry *entry, int64_t *out) +{ + if (!entry->remaining_count) + return false; + + // Somewhat excessively lenient, intended for display. + // TIFF 6.0 only directly suggests that a reader is should accept + // any of BYTE/SHORT/LONG for unsigned integers. + switch (entry->type) { + case BYTE: + case ASCII: + case UNDEFINED: + *out = *entry->p; + return true; + case SBYTE: + *out = (int8_t) *entry->p; + return true; + case SHORT: + *out = self->un->u16(entry->p); + return true; + case SSHORT: + *out = (int16_t) self->un->u16(entry->p); + return true; + case LONG: + case IFD: + *out = self->un->u32(entry->p); + return true; + case SLONG: + *out = (int32_t) self->un->u32(entry->p); + return true; + default: + return false; + } +} + +static bool +tiffer_rational(const struct tiffer *self, const struct tiffer_entry *entry, + int64_t *numerator, int64_t *denominator) +{ + if (!entry->remaining_count) + return false; + + // Somewhat excessively lenient, intended for display. + switch (entry->type) { + case RATIONAL: + *numerator = self->un->u32(entry->p); + *denominator = self->un->u32(entry->p + 4); + return true; + case SRATIONAL: + *numerator = (int32_t) self->un->u32(entry->p); + *denominator = (int32_t) self->un->u32(entry->p + 4); + return true; + default: + if (tiffer_integer(self, entry, numerator)) { + *denominator = 1; + return true; + } + return false; + } +} + +static bool +tiffer_real( + const struct tiffer *self, const struct tiffer_entry *entry, double *out) +{ + if (!entry->remaining_count) + return false; + + // Somewhat excessively lenient, intended for display. + // Assuming the host architecture uses IEEE 754. + switch (entry->type) { + int64_t numerator, denominator; + case FLOAT: + *out = *(float *) entry->p; + return true; + case DOUBLE: + *out = *(double *) entry->p; + return true; + default: + if (tiffer_rational(self, entry, &numerator, &denominator)) { + *out = (double) numerator / denominator; + return true; + } + return false; + } +} + +static bool +tiffer_next_entry(struct tiffer *self, struct tiffer_entry *entry) +{ + if (!self->remaining_fields) + return false; + + uint16_t type = entry->type = 0xFFFF; + if (!tiffer_u16(self, &entry->tag) || !tiffer_u16(self, &type) || + !tiffer_u32(self, &entry->remaining_count)) + return false; + + // Short values may and will be inlined, rather than pointed to. + size_t values_size = tiffer_value_size(type) * entry->remaining_count; + uint32_t offset = 0; + if (values_size <= sizeof offset) { + entry->p = self->p; + self->p += sizeof offset; + } else if (tiffer_u32(self, &offset)) { + entry->p = self->begin + offset; + } else { + return false; + } + + // All entries are pre-checked not to overflow. + if (entry->p + values_size > self->end) + return false; + + // Setting it at the end may provide an indication while debugging. + entry->type = type; + self->remaining_fields--; + return true; +} diff --git a/tools/info.h b/tools/info.h index 28cfb36..8dcd3d2 100644 --- a/tools/info.h +++ b/tools/info.h @@ -21,348 +21,10 @@ #include #include -// --- Utilities --------------------------------------------------------------- - -static char * -binhex(const uint8_t *data, size_t len) -{ - static const char *alphabet = "0123456789abcdef"; - char *buf = calloc(1, len * 2 + 1), *p = buf; - for (size_t i = 0; i < len; i++) { - *p++ = alphabet[data[i] >> 4]; - *p++ = alphabet[data[i] & 0xF]; - } - return buf; -} - -static uint64_t -u64be(const uint8_t *p) -{ - return (uint64_t) p[0] << 56 | (uint64_t) p[1] << 48 | - (uint64_t) p[2] << 40 | (uint64_t) p[3] << 32 | - (uint64_t) p[4] << 24 | p[5] << 16 | p[6] << 8 | p[7]; -} - -static uint32_t -u32be(const uint8_t *p) -{ - return (uint32_t) p[0] << 24 | p[1] << 16 | p[2] << 8 | p[3]; -} - -static uint16_t -u16be(const uint8_t *p) -{ - return (uint16_t) p[0] << 8 | p[1]; -} - -static uint64_t -u64le(const uint8_t *p) -{ - return (uint64_t) p[7] << 56 | (uint64_t) p[6] << 48 | - (uint64_t) p[5] << 40 | (uint64_t) p[4] << 32 | - (uint64_t) p[3] << 24 | p[2] << 16 | p[1] << 8 | p[0]; -} - -static uint32_t -u32le(const uint8_t *p) -{ - return (uint32_t) p[3] << 24 | p[2] << 16 | p[1] << 8 | p[0]; -} - -static uint16_t -u16le(const uint8_t *p) -{ - return (uint16_t) p[1] << 8 | p[0]; -} - -// --- TIFF -------------------------------------------------------------------- -// libtiff is a mess, and the format is not particularly complicated. -// Exiv2 is senselessly copylefted, and cannot do much. -// libexif is only marginally better. -// ExifTool is too user-oriented. - -static struct un { - uint64_t (*u64) (const uint8_t *); - uint32_t (*u32) (const uint8_t *); - uint16_t (*u16) (const uint8_t *); -} unbe = {u64be, u32be, u16be}, unle = {u64le, u32le, u16le}; - -struct tiffer { - struct un *un; - const uint8_t *begin, *p, *end; - uint16_t remaining_fields; -}; - -static bool -tiffer_u32(struct tiffer *self, uint32_t *u) -{ - if (self->p < self->begin || self->p + 4 > self->end) - return false; - - *u = self->un->u32(self->p); - self->p += 4; - return true; -} - -static bool -tiffer_u16(struct tiffer *self, uint16_t *u) -{ - if (self->p < self->begin || self->p + 2 > self->end) - return false; - - *u = self->un->u16(self->p); - self->p += 2; - return true; -} - -// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -static bool -tiffer_init(struct tiffer *self, const uint8_t *tiff, size_t len) -{ - self->un = NULL; - self->begin = self->p = tiff; - self->end = tiff + len; - self->remaining_fields = 0; - - const uint8_t - le[4] = {'I', 'I', 42, 0}, - be[4] = {'M', 'M', 0, 42}; - - if (tiff + 8 > self->end) - return false; - else if (!memcmp(tiff, le, sizeof le)) - self->un = &unle; - else if (!memcmp(tiff, be, sizeof be)) - self->un = &unbe; - else - return false; - - self->p = tiff + 4; - // The first IFD needs to be read by caller explicitly, - // even though it's required to be present by TIFF 6.0. - return true; -} - -/// Read the next IFD in a sequence. -static bool -tiffer_next_ifd(struct tiffer *self) -{ - // All fields from any previous IFD need to be read first. - if (self->remaining_fields) - return false; - - uint32_t ifd_offset = 0; - if (!tiffer_u32(self, &ifd_offset)) - return false; - - // There is nothing more to read, this chain has terminated. - if (!ifd_offset) - return false; - - // Note that TIFF 6.0 requires there to be at least one entry, - // but there is no need for us to check it. - self->p = self->begin + ifd_offset; - return tiffer_u16(self, &self->remaining_fields); -} - -/// Initialize a derived TIFF reader for a subIFD at the given location. -static bool -tiffer_subifd(struct tiffer *self, uint32_t offset, struct tiffer *subreader) -{ - *subreader = *self; - subreader->p = subreader->begin + offset; - return tiffer_u16(subreader, &subreader->remaining_fields); -} - -enum tiffer_type { - BYTE = 1, ASCII, SHORT, LONG, RATIONAL, - SBYTE, UNDEFINED, SSHORT, SLONG, SRATIONAL, FLOAT, DOUBLE, - IFD // This last type from TIFF Technical Note 1 isn't really used much. -}; - -static size_t -tiffer_value_size(enum tiffer_type type) -{ - switch (type) { - case BYTE: - case SBYTE: - case ASCII: - case UNDEFINED: - return 1; - case SHORT: - case SSHORT: - return 2; - case LONG: - case SLONG: - case FLOAT: - case IFD: - return 4; - case RATIONAL: - case SRATIONAL: - case DOUBLE: - return 8; - default: - return 0; - } -} - -/// A lean iterator for values within entries. -struct tiffer_entry { - uint16_t tag; - enum tiffer_type type; - // For {S,}BYTE, ASCII, UNDEFINED, use these fields directly. - const uint8_t *p; - uint32_t remaining_count; -}; - -static bool -tiffer_next_value(struct tiffer_entry *entry) -{ - if (!entry->remaining_count) - return false; - - entry->p += tiffer_value_size(entry->type); - entry->remaining_count--; - return true; -} - -static bool -tiffer_integer( - const struct tiffer *self, const struct tiffer_entry *entry, int64_t *out) -{ - if (!entry->remaining_count) - return false; - - // Somewhat excessively lenient, intended for display. - // TIFF 6.0 only directly suggests that a reader is should accept - // any of BYTE/SHORT/LONG for unsigned integers. - switch (entry->type) { - case BYTE: - case ASCII: - case UNDEFINED: - *out = *entry->p; - return true; - case SBYTE: - *out = (int8_t) *entry->p; - return true; - case SHORT: - *out = self->un->u16(entry->p); - return true; - case SSHORT: - *out = (int16_t) self->un->u16(entry->p); - return true; - case LONG: - case IFD: - *out = self->un->u32(entry->p); - return true; - case SLONG: - *out = (int32_t) self->un->u32(entry->p); - return true; - default: - return false; - } -} - -static bool -tiffer_rational(const struct tiffer *self, const struct tiffer_entry *entry, - int64_t *numerator, int64_t *denominator) -{ - if (!entry->remaining_count) - return false; - - // Somewhat excessively lenient, intended for display. - switch (entry->type) { - case RATIONAL: - *numerator = self->un->u32(entry->p); - *denominator = self->un->u32(entry->p + 4); - return true; - case SRATIONAL: - *numerator = (int32_t) self->un->u32(entry->p); - *denominator = (int32_t) self->un->u32(entry->p + 4); - return true; - default: - if (tiffer_integer(self, entry, numerator)) { - *denominator = 1; - return true; - } - return false; - } -} - -static bool -tiffer_real( - const struct tiffer *self, const struct tiffer_entry *entry, double *out) -{ - if (!entry->remaining_count) - return false; - - // Somewhat excessively lenient, intended for display. - // Assuming the host architecture uses IEEE 754. - switch (entry->type) { - int64_t numerator, denominator; - case FLOAT: - *out = *(float *) entry->p; - return true; - case DOUBLE: - *out = *(double *) entry->p; - return true; - default: - if (tiffer_rational(self, entry, &numerator, &denominator)) { - *out = (double) numerator / denominator; - return true; - } - return false; - } -} - -static bool -tiffer_next_entry(struct tiffer *self, struct tiffer_entry *entry) -{ - if (!self->remaining_fields) - return false; - - uint16_t type = entry->type = 0xFFFF; - if (!tiffer_u16(self, &entry->tag) || !tiffer_u16(self, &type) || - !tiffer_u32(self, &entry->remaining_count)) - return false; - - // Short values may and will be inlined, rather than pointed to. - size_t values_size = tiffer_value_size(type) * entry->remaining_count; - uint32_t offset = 0; - if (values_size <= sizeof offset) { - entry->p = self->p; - self->p += sizeof offset; - } else if (tiffer_u32(self, &offset)) { - entry->p = self->begin + offset; - } else { - return false; - } - - // All entries are pre-checked not to overflow. - if (entry->p + values_size > self->end) - return false; - - // Setting it at the end may provide an indication while debugging. - entry->type = type; - self->remaining_fields--; - return true; -} - -// --- TIFF/Exif tags ---------------------------------------------------------- - -struct tiff_value { - const char *name; - uint16_t value; -}; - -struct tiff_entry { - const char *name; - uint16_t tag; - struct tiff_value *values; -}; +// --- TIFF/Exif --------------------------------------------------------------- #include "tiff-tables.h" +#include "tiffer.h" // TODO(p): Consider if these can't be inlined into `tiff_entries`. static struct { @@ -376,6 +38,27 @@ static struct { {} }; +// --- Utilities --------------------------------------------------------------- + +#define u64be tiffer_u64be +#define u32be tiffer_u32be +#define u16be tiffer_u16be +#define u64le tiffer_u64le +#define u32le tiffer_u32le +#define u16le tiffer_u16le + +static char * +binhex(const uint8_t *data, size_t len) +{ + static const char *alphabet = "0123456789abcdef"; + char *buf = calloc(1, len * 2 + 1), *p = buf; + for (size_t i = 0; i < len; i++) { + *p++ = alphabet[data[i] >> 4]; + *p++ = alphabet[data[i] & 0xF]; + } + return buf; +} + // --- Analysis ---------------------------------------------------------------- static jv -- cgit v1.2.3-70-g09d2