Make TIFF and JPEG info extractors co-recursive
This commit is contained in:
579
tools/info.h
579
tools/info.h
@@ -1,7 +1,7 @@
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//
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// info.h: metadata extraction utilities
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//
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// Copyright (c) 2021, Přemysl Eric Janouch <p@janouch.name>
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// Copyright (c) 2021 - 2023, Přemysl Eric Janouch <p@janouch.name>
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//
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// Permission to use, copy, modify, and/or distribute this software for any
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// purpose with or without fee is hereby granted.
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@@ -17,9 +17,9 @@
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#include <jv.h>
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#include <stdbool.h>
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#include <stdlib.h>
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#include <string.h>
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#include <stdbool.h>
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// --- Utilities ---------------------------------------------------------------
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@@ -401,6 +401,9 @@ add_error(jv o, const char *message)
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return jv_object_set(o, jv_string("error"), jv_string(message));
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}
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// Forward declaration.
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static jv parse_jpeg(jv o, const uint8_t *p, size_t len);
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// --- Exif --------------------------------------------------------------------
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static jv parse_exif_ifd(struct tiffer *T, const struct tiff_entry *info);
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@@ -529,10 +532,51 @@ parse_exif_entry(jv o, struct tiffer *T, struct tiffer_entry *entry,
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static jv
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parse_exif_ifd(struct tiffer *T, const struct tiff_entry *info)
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{
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int64_t compression = 0,
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jpeg = 0, jpeg_length = 0, strip_offsets = 0, strip_byte_counts = 0;
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jv ifd = jv_object();
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struct tiffer_entry entry = {};
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while (tiffer_next_entry(T, &entry))
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while (tiffer_next_entry(T, &entry)) {
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switch (entry.tag) {
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case TIFF_Compression:
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tiffer_integer(T, &entry, &compression);
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break;
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case TIFF_JPEGInterchangeFormat:
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tiffer_integer(T, &entry, &jpeg);
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break;
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case TIFF_JPEGInterchangeFormatLength:
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tiffer_integer(T, &entry, &jpeg_length);
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break;
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case TIFF_StripOffsets:
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tiffer_integer(T, &entry, &strip_offsets);
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break;
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case TIFF_StripByteCounts:
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tiffer_integer(T, &entry, &strip_byte_counts);
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break;
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}
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ifd = parse_exif_entry(ifd, T, &entry, info);
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}
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// This is how Exif specifies it, which doesn't follow TIFF 6.0.
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if (info == tiff_entries && compression == TIFF_Compression_JPEG &&
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jpeg > 0 && jpeg_length > 0 &&
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jpeg + jpeg_length < (T->end - T->begin)) {
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ifd = jv_set(ifd, jv_string("JPEG image data"),
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parse_jpeg(
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jv_object(), T->begin + jpeg, jpeg_length));
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}
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// Theoretically, there may be more strips, but this is not expected.
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if (info == tiff_entries &&
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compression == TIFF_Compression_JPEGDatastream &&
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strip_offsets > 0 && strip_byte_counts > 0 &&
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strip_offsets + strip_byte_counts < (T->end - T->begin)) {
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ifd = jv_set(ifd, jv_string("JPEG image data"),
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parse_jpeg(
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jv_object(), T->begin + strip_offsets, strip_byte_counts));
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}
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return ifd;
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}
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@@ -901,3 +945,532 @@ parse_icc(jv o, const uint8_t *profile, size_t profile_len)
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// The description is required, so this should be unreachable.
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return jv_set(o, jv_string("ICC"), jv_bool(true));
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}
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// --- Multi-Picture Format ----------------------------------------------------
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enum {
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MPF_MPFVersion = 45056,
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MPF_NumberOfImages = 45057,
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MPF_MPEntry = 45058,
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MPF_ImageUIDList = 45059,
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MPF_TotalFrames = 45060,
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MPF_MPIndividualNum = 45313,
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MPF_PanOrientation = 45569,
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MPF_PanOverlap_H = 45570,
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MPF_PanOverlap_V = 45571,
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MPF_BaseViewpointNum = 45572,
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MPF_ConvergenceAngle = 45573,
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MPF_BaselineLength = 45574,
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MPF_VerticalDivergence = 45575,
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MPF_AxisDistance_X = 45576,
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MPF_AxisDistance_Y = 45577,
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MPF_AxisDistance_Z = 45578,
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MPF_YawAngle = 45579,
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MPF_PitchAngle = 45580,
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MPF_RollAngle = 45581
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};
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static struct tiff_entry mpf_entries[] = {
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{"MP Format Version Number", MPF_MPFVersion, NULL},
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{"Number of Images", MPF_NumberOfImages, NULL},
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{"MP Entry", MPF_MPEntry, NULL},
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{"Individual Image Unique ID List", MPF_ImageUIDList, NULL},
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{"Total Number of Captured Frames", MPF_TotalFrames, NULL},
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{"MP Individual Image Number", MPF_MPIndividualNum, NULL},
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{"Panorama Scanning Orientation", MPF_PanOrientation, NULL},
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{"Panorama Horizontal Overlap", MPF_PanOverlap_H, NULL},
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{"Panorama Vertical Overlap", MPF_PanOverlap_V, NULL},
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{"Base Viewpoint Number", MPF_BaseViewpointNum, NULL},
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{"Convergence Angle", MPF_ConvergenceAngle, NULL},
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{"Baseline Length", MPF_BaselineLength, NULL},
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{"Divergence Angle", MPF_VerticalDivergence, NULL},
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{"Horizontal Axis Distance", MPF_AxisDistance_X, NULL},
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{"Vertical Axis Distance", MPF_AxisDistance_Y, NULL},
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{"Collimation Axis Distance", MPF_AxisDistance_Z, NULL},
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{"Yaw Angle", MPF_YawAngle, NULL},
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{"Pitch Angle", MPF_PitchAngle, NULL},
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{"Roll Angle", MPF_RollAngle, NULL},
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{}
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};
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static uint32_t
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parse_mpf_mpentry(jv *a, const uint8_t *p, struct tiffer *T)
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{
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uint32_t attrs = T->un->u32(p);
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uint32_t offset = T->un->u32(p + 8);
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uint32_t type_number = attrs & 0xFFFFFF;
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jv type = jv_number(type_number);
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switch (type_number) {
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break; case 0x030000: type = jv_string("Baseline MP Primary Image");
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break; case 0x010001: type = jv_string("Large Thumbnail - VGA");
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break; case 0x010002: type = jv_string("Large Thumbnail - Full HD");
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break; case 0x020001: type = jv_string("Multi-Frame Image Panorama");
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break; case 0x020002: type = jv_string("Multi-Frame Image Disparity");
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break; case 0x020003: type = jv_string("Multi-Frame Image Multi-Angle");
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break; case 0x000000: type = jv_string("Undefined");
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}
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uint32_t format_number = (attrs >> 24) & 0x7;
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jv format = jv_number(format_number);
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if (format_number == 0)
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format = jv_string("JPEG");
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*a = jv_array_append(*a, JV_OBJECT(
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jv_string("Individual Image Attribute"), JV_OBJECT(
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jv_string("Dependent Parent Image"), jv_bool((attrs >> 31) & 1),
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jv_string("Dependent Child Image"), jv_bool((attrs >> 30) & 1),
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jv_string("Representative Image"), jv_bool((attrs >> 29) & 1),
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jv_string("Reserved"), jv_number((attrs >> 27) & 0x3),
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jv_string("Image Data Format"), format,
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jv_string("MP Type Code"), type
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),
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jv_string("Individual Image Size"),
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jv_number(T->un->u32(p + 4)),
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jv_string("Individual Image Data Offset"),
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jv_number(offset),
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jv_string("Dependent Image 1 Entry Number"),
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jv_number(T->un->u16(p + 12)),
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jv_string("Dependent Image 2 Entry Number"),
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jv_number(T->un->u16(p + 14))
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));
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// Don't report non-JPEGs, even though they're unlikely.
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return format_number == 0 ? offset : 0;
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}
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static jv
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parse_mpf_index_entry(jv o, const uint8_t ***offsets, struct tiffer *T,
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struct tiffer_entry *entry)
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{
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// 5.2.3.3. MP Entry
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if (entry->tag != MPF_MPEntry || entry->type != UNDEFINED ||
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entry->remaining_count % 16) {
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return parse_exif_entry(o, T, entry, mpf_entries);
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}
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uint32_t count = entry->remaining_count / 16;
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jv a = jv_array_sized(count);
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const uint8_t **out = *offsets = calloc(sizeof *out, count + 1);
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for (uint32_t i = 0; i < count; i++) {
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uint32_t offset = parse_mpf_mpentry(&a, entry->p + i * 16, T);
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if (offset)
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*out++ = T->begin + offset;
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}
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return jv_set(o, jv_string("MP Entry"), a);
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}
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static jv
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parse_mpf_index_ifd(const uint8_t ***offsets, struct tiffer *T)
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{
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jv ifd = jv_object();
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struct tiffer_entry entry = {};
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while (tiffer_next_entry(T, &entry))
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ifd = parse_mpf_index_entry(ifd, offsets, T, &entry);
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return ifd;
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}
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static jv
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parse_mpf(jv o, const uint8_t ***offsets, const uint8_t *p, size_t len)
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{
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struct tiffer T;
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if (!tiffer_init(&T, p, len) || !tiffer_next_ifd(&T))
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return add_warning(o, "invalid MPF segment");
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// First image: IFD0 is Index IFD, any IFD1 is Attribute IFD.
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// Other images: IFD0 is Attribute IFD, there is no Index IFD.
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if (!*offsets) {
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o = add_to_subarray(o, "MPF", parse_mpf_index_ifd(offsets, &T));
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if (!tiffer_next_ifd(&T))
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return o;
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}
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// This isn't optimal, but it will do.
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return add_to_subarray(o, "MPF", parse_exif_ifd(&T, mpf_entries));
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}
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// --- JPEG --------------------------------------------------------------------
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// Because the JPEG file format is simple, just do it manually.
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// See: https://www.w3.org/Graphics/JPEG/itu-t81.pdf
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enum {
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TEM = 0x01,
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SOF0 = 0xC0, SOF1, SOF2, SOF3,
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DHT = 0xC4,
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SOF5, SOF6, SOF7,
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JPG = 0xC8,
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SOF9, SOF10, SOF11,
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DAC = 0xCC,
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SOF13, SOF14, SOF15,
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RST0 = 0xD0, RST1, RST2, RST3, RST4, RST5, RST6, RST7,
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SOI = 0xD8,
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EOI = 0xD9,
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SOS = 0xDA,
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DQT = 0xDB,
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DNL = 0xDC,
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DRI = 0xDD,
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DHP = 0xDE,
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EXP = 0xDF,
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APP0 = 0xE0, APP1, APP2, APP3, APP4, APP5, APP6, APP7,
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APP8, APP9, APP10, APP11, APP12, APP13, APP14, APP15,
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JPG0 = 0xF0, JPG1, JPG2, JPG3, JPG4, JPG5, JPG6, JPG7,
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JPG8, JPG9, JPG10, JPG11, JPG12, JPG13,
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COM = 0xFE
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};
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// The rest is "RES (Reserved)", except for 0xFF (filler) and 0x00 (invalid).
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static const char *marker_ids[0xFF] = {
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[TEM] = "TEM",
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[SOF0] = "SOF0", [SOF1] = "SOF1", [SOF2] = "SOF2", [SOF3] = "SOF3",
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[DHT] = "DHT", [SOF5] = "SOF5", [SOF6] = "SOF6", [SOF7] = "SOF7",
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[JPG] = "JPG", [SOF9] = "SOF9", [SOF10] = "SOF10", [SOF11] = "SOF11",
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[DAC] = "DAC", [SOF13] = "SOF13", [SOF14] = "SOF14", [SOF15] = "SOF15",
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[RST0] = "RST0", [RST1] = "RST1", [RST2] = "RST2", [RST3] = "RST3",
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[RST4] = "RST4", [RST5] = "RST5", [RST6] = "RST6", [RST7] = "RST7",
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[SOI] = "SOI", [EOI] = "EOI", [SOS] = "SOS", [DQT] = "DQT",
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[DNL] = "DNL", [DRI] = "DRI", [DHP] = "DHP", [EXP] = "EXP",
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[APP0] = "APP0", [APP1] = "APP1", [APP2] = "APP2", [APP3] = "APP3",
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[APP4] = "APP4", [APP5] = "APP5", [APP6] = "APP6", [APP7] = "APP7",
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[APP8] = "APP8", [APP9] = "APP9", [APP10] = "APP10", [APP11] = "APP11",
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[APP12] = "APP12", [APP13] = "APP13", [APP14] = "APP14", [APP15] = "APP15",
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[JPG0] = "JPG0", [JPG1] = "JPG1", [JPG2] = "JPG2", [JPG3] = "JPG3",
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[JPG4] = "JPG4", [JPG5] = "JPG5", [JPG6] = "JPG6", [JPG7] = "JPG7",
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[JPG8] = "JPG8", [JPG9] = "JPG9", [JPG10] = "JPG10", [JPG11] = "JPG11",
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[JPG12] = "JPG12", [JPG13] = "JPG13", [COM] = "COM"
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};
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// The rest is "RES (Reserved)", except for 0xFF (filler) and 0x00 (invalid).
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static const char *marker_descriptions[0xFF] = {
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[TEM] = "For temporary private use in arithmetic coding",
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[SOF0] = "Baseline DCT",
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[SOF1] = "Extended sequential DCT",
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[SOF2] = "Progressive DCT",
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[SOF3] = "Lossless (sequential)",
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[DHT] = "Define Huffman table(s)",
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[SOF5] = "Differential sequential DCT",
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[SOF6] = "Differential progressive DCT",
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[SOF7] = "Differential lossless (sequential)",
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[JPG] = "Reserved for JPEG extensions",
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[SOF9] = "Extended sequential DCT",
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[SOF10] = "Progressive DCT",
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[SOF11] = "Lossless (sequential)",
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[DAC] = "Define arithmetic coding conditioning(s)",
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[SOF13] = "Differential sequential DCT",
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[SOF14] = "Differential progressive DCT",
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[SOF15] = "Differential lossless (sequential)",
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[RST0] = "Restart with module 8 count 0",
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[RST1] = "Restart with module 8 count 1",
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[RST2] = "Restart with module 8 count 2",
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[RST3] = "Restart with module 8 count 3",
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[RST4] = "Restart with module 8 count 4",
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[RST5] = "Restart with module 8 count 5",
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[RST6] = "Restart with module 8 count 6",
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[RST7] = "Restart with module 8 count 7",
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[SOI] = "Start of image",
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[EOI] = "End of image",
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[SOS] = "Start of scan",
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[DQT] = "Define quantization table(s)",
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[DNL] = "Define number of lines",
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[DRI] = "Define restart interval",
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[DHP] = "Define hierarchical progression",
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[EXP] = "Expand reference component(s)",
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[APP0] = "Reserved for application segments, 0",
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[APP1] = "Reserved for application segments, 1",
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[APP2] = "Reserved for application segments, 2",
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[APP3] = "Reserved for application segments, 3",
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[APP4] = "Reserved for application segments, 4",
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[APP5] = "Reserved for application segments, 5",
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[APP6] = "Reserved for application segments, 6",
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[APP7] = "Reserved for application segments, 7",
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[APP8] = "Reserved for application segments, 8",
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[APP9] = "Reserved for application segments, 9",
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[APP10] = "Reserved for application segments, 10",
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[APP11] = "Reserved for application segments, 11",
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[APP12] = "Reserved for application segments, 12",
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[APP13] = "Reserved for application segments, 13",
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[APP14] = "Reserved for application segments, 14",
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[APP15] = "Reserved for application segments, 15",
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[JPG0] = "Reserved for JPEG extensions, 0",
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[JPG1] = "Reserved for JPEG extensions, 1",
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[JPG2] = "Reserved for JPEG extensions, 2",
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[JPG3] = "Reserved for JPEG extensions, 3",
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[JPG4] = "Reserved for JPEG extensions, 4",
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[JPG5] = "Reserved for JPEG extensions, 5",
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[JPG6] = "Reserved for JPEG extensions, 6",
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[JPG7] = "Reserved for JPEG extensions, 7",
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[JPG8] = "Reserved for JPEG extensions, 8",
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[JPG9] = "Reserved for JPEG extensions, 9",
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[JPG10] = "Reserved for JPEG extensions, 10",
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[JPG11] = "Reserved for JPEG extensions, 11",
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[JPG12] = "Reserved for JPEG extensions, 12",
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[JPG13] = "Reserved for JPEG extensions, 13",
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[COM] = "Comment",
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};
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// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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struct data {
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bool ended;
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uint8_t *exif, *icc, *psir;
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size_t exif_len, icc_len, psir_len;
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int icc_sequence, icc_done;
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const uint8_t **mpf_offsets, **mpf_next;
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};
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static void
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parse_append(uint8_t **buffer, size_t *buffer_len, const uint8_t *p, size_t len)
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{
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size_t buffer_longer = *buffer_len + len;
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*buffer = realloc(*buffer, buffer_longer);
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memcpy(*buffer + *buffer_len, p, len);
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*buffer_len = buffer_longer;
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}
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static const uint8_t *
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parse_marker(uint8_t marker, const uint8_t *p, const uint8_t *end,
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struct data *data, jv *o)
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{
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// Suspected: MJPEG? Undetected format recursion, e.g., thumbnails?
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// Found: Random metadata! Multi-Picture Format!
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if ((data->ended = marker == EOI)) {
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// TODO(p): Handle Exifs independently--flush the last one.
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if ((data->mpf_next || (data->mpf_next = data->mpf_offsets)) &&
|
||||
*data->mpf_next)
|
||||
return *data->mpf_next++;
|
||||
if (p != end)
|
||||
*o = add_warning(*o, "trailing data");
|
||||
}
|
||||
|
||||
// These markers stand alone, not starting a marker segment.
|
||||
switch (marker) {
|
||||
case RST0:
|
||||
case RST1:
|
||||
case RST2:
|
||||
case RST3:
|
||||
case RST4:
|
||||
case RST5:
|
||||
case RST6:
|
||||
case RST7:
|
||||
*o = add_warning(*o, "unexpected restart marker");
|
||||
// Fall-through
|
||||
case SOI:
|
||||
case EOI:
|
||||
case TEM:
|
||||
return p;
|
||||
}
|
||||
|
||||
uint16_t length = p[0] << 8 | p[1];
|
||||
const uint8_t *payload = p + 2;
|
||||
if ((p += length) > end) {
|
||||
*o = add_error(*o, "runaway marker segment");
|
||||
return NULL;
|
||||
}
|
||||
|
||||
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:
|
||||
case DHP: // B.2.2 and B.3.2.
|
||||
// As per B.2.5, Y can be zero, then there needs to be a DNL segment.
|
||||
*o = add_to_subarray(*o, "info", JV_OBJECT(
|
||||
jv_string("type"), jv_string(marker_descriptions[marker]),
|
||||
jv_string("bits"), jv_number(payload[0]),
|
||||
jv_string("height"), jv_number(payload[1] << 8 | payload[2]),
|
||||
jv_string("width"), jv_number(payload[3] << 8 | payload[4]),
|
||||
jv_string("components"), jv_number(payload[5])
|
||||
));
|
||||
return p;
|
||||
}
|
||||
|
||||
// See B.1.1.5, we can brute-force our way through the entropy-coded data.
|
||||
if (marker == SOS) {
|
||||
while (p + 2 <= end && (p[0] != 0xFF || p[1] < 0xC0 || p[1] > 0xFE ||
|
||||
(p[1] >= RST0 && p[1] <= RST7)))
|
||||
p++;
|
||||
return p;
|
||||
}
|
||||
|
||||
// "The interpretation is left to the application."
|
||||
if (marker == COM) {
|
||||
int superascii = 0;
|
||||
char *buf = calloc(3, p - payload), *bufp = buf;
|
||||
for (const uint8_t *q = payload; q < p; q++) {
|
||||
if (*q < 128) {
|
||||
*bufp++ = *q;
|
||||
} else {
|
||||
superascii++;
|
||||
*bufp++ = 0xC0 | (*q >> 6);
|
||||
*bufp++ = 0x80 | (*q & 0x3F);
|
||||
}
|
||||
}
|
||||
*bufp++ = 0;
|
||||
*o = add_to_subarray(*o, "comments", jv_string(buf));
|
||||
free(buf);
|
||||
|
||||
if (superascii)
|
||||
*o = add_warning(*o, "super-ASCII comments");
|
||||
}
|
||||
|
||||
// These mostly contain an ASCII string header, following JPEG FIF:
|
||||
//
|
||||
// "Application-specific APP0 marker segments are identified
|
||||
// by a zero terminated string which identifies the application
|
||||
// (not 'JFIF' or 'JFXX')."
|
||||
if (marker >= APP0 && marker <= APP15) {
|
||||
const uint8_t *nul = memchr(payload, 0, p - payload);
|
||||
int unprintable = !nul;
|
||||
if (nul) {
|
||||
for (const uint8_t *q = payload; q < nul; q++)
|
||||
unprintable += *q < 32 || *q >= 127;
|
||||
}
|
||||
*o = add_to_subarray(*o, "apps",
|
||||
unprintable ? jv_null() : jv_string((const char *) payload));
|
||||
}
|
||||
|
||||
// CIPA DC-007 (Multi-Picture Format) 5.2
|
||||
// http://fileformats.archiveteam.org/wiki/Multi-Picture_Format
|
||||
if (marker == APP2 && p - payload >= 8 && !memcmp(payload, "MPF\0", 4)) {
|
||||
payload += 4;
|
||||
*o = parse_mpf(*o, &data->mpf_offsets, payload, p - payload);
|
||||
}
|
||||
|
||||
// CIPA DC-006 (Stereo Still Image Format for Digital Cameras)
|
||||
// TODO(p): Handle by properly skipping trailing data (use Stim offsets).
|
||||
|
||||
// https://www.w3.org/Graphics/JPEG/jfif3.pdf
|
||||
if (marker == APP0 && p - payload >= 14 && !memcmp(payload, "JFIF\0", 5)) {
|
||||
payload += 5;
|
||||
|
||||
jv units = jv_number(payload[2]);
|
||||
switch (payload[2]) {
|
||||
break; case 0: units = jv_null();
|
||||
break; case 1: units = jv_string("DPI");
|
||||
break; case 2: units = jv_string("dots per cm");
|
||||
}
|
||||
|
||||
// The rest is picture data.
|
||||
*o = add_to_subarray(*o, "JFIF", JV_OBJECT(
|
||||
jv_string("version"), jv_number(payload[0] * 100 + payload[1]),
|
||||
jv_string("units"), units,
|
||||
jv_string("density-x"), jv_number(payload[3] << 8 | payload[4]),
|
||||
jv_string("density-y"), jv_number(payload[5] << 8 | payload[6]),
|
||||
jv_string("thumbnail-w"), jv_number(payload[7]),
|
||||
jv_string("thumbnail-h"), jv_number(payload[8])
|
||||
));
|
||||
}
|
||||
if (marker == APP0 && p - payload >= 6 && !memcmp(payload, "JFXX\0", 5)) {
|
||||
payload += 5;
|
||||
|
||||
jv extension = jv_number(payload[0]);
|
||||
switch (payload[0]) {
|
||||
break; case 0x10: extension = jv_string("JPEG thumbnail");
|
||||
break; case 0x11: extension = jv_string("Paletted thumbnail");
|
||||
break; case 0x13: extension = jv_string("RGB thumbnail");
|
||||
}
|
||||
|
||||
// The rest is picture data.
|
||||
*o = add_to_subarray(*o, "JFXX",
|
||||
JV_OBJECT(jv_string("extension"), extension));
|
||||
}
|
||||
|
||||
// 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
|
||||
if (marker == APP1 && p - payload >= 6 && !memcmp(payload, "Exif\0", 5)) {
|
||||
payload += 6;
|
||||
if (payload[-1] != 0)
|
||||
*o = add_warning(*o, "weirdly padded Exif header");
|
||||
if (data->exif)
|
||||
*o = add_warning(*o, "multiple Exif segments");
|
||||
parse_append(&data->exif, &data->exif_len, payload, p - payload);
|
||||
}
|
||||
|
||||
// https://www.color.org/specification/ICC1v43_2010-12.pdf B.4
|
||||
if (marker == APP2 && p - payload >= 14 &&
|
||||
!memcmp(payload, "ICC_PROFILE\0", 12) && !data->icc_done &&
|
||||
payload[12] == ++data->icc_sequence && payload[13] >= payload[12]) {
|
||||
payload += 14;
|
||||
parse_append(&data->icc, &data->icc_len, payload, p - payload);
|
||||
data->icc_done = payload[-1] == data->icc_sequence;
|
||||
}
|
||||
|
||||
// Adobe XMP Specification Part 3: Storage in Files, 2020/1, 1.1.3 + 3.1.3
|
||||
// https://www.adobe.com/devnet-apps/photoshop/fileformatashtml/
|
||||
if (marker == APP13 && p - payload >= 14 &&
|
||||
!memcmp(payload, "Photoshop 3.0\0", 14)) {
|
||||
payload += 14;
|
||||
parse_append(&data->psir, &data->psir_len, payload, p - payload);
|
||||
}
|
||||
|
||||
// TODO(p): Extract all XMP segments.
|
||||
return p;
|
||||
}
|
||||
|
||||
static jv
|
||||
parse_jpeg(jv o, const uint8_t *p, size_t len)
|
||||
{
|
||||
struct data data = {};
|
||||
const uint8_t *end = p + len;
|
||||
jv markers = jv_array();
|
||||
while (p) {
|
||||
// This is an expectable condition, use a simple warning.
|
||||
if (p + 2 > end) {
|
||||
if (!data.ended)
|
||||
o = add_warning(o, "unexpected EOF");
|
||||
break;
|
||||
}
|
||||
if (*p++ != 0xFF || *p == 0) {
|
||||
if (!data.ended)
|
||||
o = add_error(o, "no marker found where one was expected");
|
||||
break;
|
||||
}
|
||||
|
||||
// Markers may be preceded by fill bytes.
|
||||
if (*p == 0xFF) {
|
||||
o = jv_object_set(o, jv_string("fillers"), jv_bool(true));
|
||||
continue;
|
||||
}
|
||||
|
||||
uint8_t marker = *p++;
|
||||
markers = jv_array_append(markers,
|
||||
jv_string(marker_ids[marker] ? marker_ids[marker] : "RES"));
|
||||
p = parse_marker(marker, p, end, &data, &o);
|
||||
}
|
||||
|
||||
if (data.exif) {
|
||||
// TODO(p): Probably extend it until the end of the JPEG,
|
||||
// seeing as, e.g., thumbnail data can overflow into follow-up segments.
|
||||
o = parse_exif(o, data.exif, data.exif_len);
|
||||
free(data.exif);
|
||||
}
|
||||
if (data.icc) {
|
||||
if (data.icc_done)
|
||||
o = parse_icc(o, data.icc, data.icc_len);
|
||||
else
|
||||
o = add_warning(o, "bad ICC profile sequence");
|
||||
free(data.icc);
|
||||
}
|
||||
if (data.psir) {
|
||||
o = parse_psir(o, data.psir, data.psir_len);
|
||||
free(data.psir);
|
||||
}
|
||||
|
||||
free(data.mpf_offsets);
|
||||
return jv_set(o, jv_string("markers"), markers);
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user