Sample files (numbers in parentheses show how many files per extension contain Exif metadata out of the total):
This page hosts a formal specification of Exchangeable image file format (Exif) using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
All Ruby code generated by Kaitai Struct depends on the Kaitai Struct runtime library for Ruby. You must add this dependency to your project before you can parse or serialize any data.
The Ruby runtime library can be installed from RubyGems:
gem install kaitai-structParse a local file and get structure in memory:
data = Exif.from_file("path/to/local/file.bin")
Or parse structure from a string of bytes:
bytes = "\x00\x01\x02..."
data = Exif.new(Kaitai::Struct::Stream.new(bytes))
After that, one can get various attributes from the structure by invoking getter methods like:
data.endianness # => get endianness
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
require 'kaitai/struct/struct'
unless Gem::Version.new(Kaitai::Struct::VERSION) >= Gem::Version.new('0.11')
raise "Incompatible Kaitai Struct Ruby API: 0.11 or later is required, but you have #{Kaitai::Struct::VERSION}"
end
##
# Sample files (numbers in parentheses show how many files per extension contain
# Exif metadata out of the total):
#
# * <https://github.com/ianare/exif-py/tree/a69bf74770caf6b333221658f5092ed69f99faac/tests/resources/jpg> (84/93 .jpg, 1/1 .jpeg)
# * <https://github.com/exiftool/exiftool/tree/2200871d9cef988051d2a99d67df3bda6cbb30a8/t/images> (34/41 .jpg, 0/1 .png)
# * <https://github.com/Exiv2/exiv2/tree/648ada43dcb35ce6077f38183ace52d5e2071f64/test/data> (85/155 .jpg, 5/23 .png)
# * <https://github.com/python-pillow/Pillow/tree/807d689a83738027b6f6e0f219a6a6dd30e01c08/Tests/images> (36/55 .jpg, 3/420 .png)
# * <https://github.com/drewnoakes/metadata-extractor-images/tree/651ad0e67aa8d43d358ad05f9bc07b52d8b9ac6e/jpg> (335/430 .jpg)
# * <https://github.com/libexif/libexif-testsuite/tree/8c1f5bbc18d2cbc80b01b3f9b3eb29546310acf2> (15/18 .jpg)
# @see https://www.cipa.jp/std/documents/download_e.html?CIPA_DC-008-2026-E Exif Version 3.1
# @see https://www.cipa.jp/std/documents/download_e.html?CIPA_DC-008-2024-E Exif Version 3.0
# @see https://web.archive.org/web/20190624045241id_/https://www.cipa.jp/std/documents/e/DC-008-Translation-2019-E.pdf Exif Version 2.32
# @see https://web.archive.org/web/20190712232333id_/https://www.cipa.jp/std/documents/e/DC-008-Translation-2016-E.pdf Exif Version 2.31
# @see https://www.cipa.jp/std/documents/e/DC-008-2012_E_C.pdf Exif Version 2.3 (with Corrigendum at the end)
# @see https://web.archive.org/web/20051228234707id_/https://tsc.jeita.or.jp/avs/data/cp3451_1.pdf Exif Version 2.21 (2003 draft)
# @see https://web.archive.org/web/20131018091152id_/https://exif.org/Exif2-2.PDF Exif Version 2.2
# @see https://web.archive.org/web/20131111073619id_/https://exif.org/Exif2-1.PDF Exif Version 2.1
class Exif < Kaitai::Struct::Struct
FIELD_TYPE = {
1 => :field_type_byte,
2 => :field_type_ascii,
3 => :field_type_short,
4 => :field_type_long,
5 => :field_type_rational,
6 => :field_type_sbyte,
7 => :field_type_undefined,
8 => :field_type_sshort,
9 => :field_type_slong,
10 => :field_type_srational,
11 => :field_type_float,
12 => :field_type_double,
13 => :field_type_ifd,
129 => :field_type_utf8,
}
I__FIELD_TYPE = FIELD_TYPE.invert
GPS_TAG = {
0 => :gps_tag_gps_version_id,
1 => :gps_tag_gps_latitude_ref,
2 => :gps_tag_gps_latitude,
3 => :gps_tag_gps_longitude_ref,
4 => :gps_tag_gps_longitude,
5 => :gps_tag_gps_altitude_ref,
6 => :gps_tag_gps_altitude,
7 => :gps_tag_gps_time_stamp,
8 => :gps_tag_gps_satellites,
9 => :gps_tag_gps_status,
10 => :gps_tag_gps_measure_mode,
11 => :gps_tag_gps_dop,
12 => :gps_tag_gps_speed_ref,
13 => :gps_tag_gps_speed,
14 => :gps_tag_gps_track_ref,
15 => :gps_tag_gps_track,
16 => :gps_tag_gps_img_direction_ref,
17 => :gps_tag_gps_img_direction,
18 => :gps_tag_gps_map_datum,
19 => :gps_tag_gps_dest_latitude_ref,
20 => :gps_tag_gps_dest_latitude,
21 => :gps_tag_gps_dest_longitude_ref,
22 => :gps_tag_gps_dest_longitude,
23 => :gps_tag_gps_dest_bearing_ref,
24 => :gps_tag_gps_dest_bearing,
25 => :gps_tag_gps_dest_distance_ref,
26 => :gps_tag_gps_dest_distance,
27 => :gps_tag_gps_processing_method,
28 => :gps_tag_gps_area_information,
29 => :gps_tag_gps_date_stamp,
30 => :gps_tag_gps_differential,
31 => :gps_tag_gps_h_positioning_error,
}
I__GPS_TAG = GPS_TAG.invert
TAG = {
1 => :tag_interop_index,
2 => :tag_interop_version,
256 => :tag_image_width,
257 => :tag_image_height,
258 => :tag_bits_per_sample,
259 => :tag_compression,
262 => :tag_photometric_interpretation,
263 => :tag_thresholding,
264 => :tag_cell_width,
265 => :tag_cell_length,
266 => :tag_fill_order,
269 => :tag_document_name,
270 => :tag_image_description,
271 => :tag_make,
272 => :tag_model,
273 => :tag_strip_offsets,
274 => :tag_orientation,
277 => :tag_samples_per_pixel,
278 => :tag_rows_per_strip,
279 => :tag_strip_byte_counts,
280 => :tag_min_sample_value,
281 => :tag_max_sample_value,
282 => :tag_x_resolution,
283 => :tag_y_resolution,
284 => :tag_planar_configuration,
285 => :tag_page_name,
286 => :tag_x_position,
287 => :tag_y_position,
288 => :tag_free_offsets,
289 => :tag_free_byte_counts,
290 => :tag_gray_response_unit,
291 => :tag_gray_response_curve,
292 => :tag_t4_options,
293 => :tag_t6_options,
296 => :tag_resolution_unit,
297 => :tag_page_number,
300 => :tag_color_response_unit,
301 => :tag_transfer_function,
305 => :tag_software,
306 => :tag_modify_date,
315 => :tag_artist,
316 => :tag_host_computer,
317 => :tag_predictor,
318 => :tag_white_point,
319 => :tag_primary_chromaticities,
320 => :tag_color_map,
321 => :tag_halftone_hints,
322 => :tag_tile_width,
323 => :tag_tile_length,
324 => :tag_tile_offsets,
325 => :tag_tile_byte_counts,
326 => :tag_bad_fax_lines,
327 => :tag_clean_fax_data,
328 => :tag_consecutive_bad_fax_lines,
330 => :tag_sub_ifd,
332 => :tag_ink_set,
333 => :tag_ink_names,
334 => :tag_numberof_inks,
336 => :tag_dot_range,
337 => :tag_target_printer,
338 => :tag_extra_samples,
339 => :tag_sample_format,
340 => :tag_s_min_sample_value,
341 => :tag_s_max_sample_value,
342 => :tag_transfer_range,
343 => :tag_clip_path,
344 => :tag_x_clip_path_units,
345 => :tag_y_clip_path_units,
346 => :tag_indexed,
347 => :tag_jpeg_tables,
351 => :tag_opi_proxy,
400 => :tag_global_parameters_ifd,
401 => :tag_profile_type,
402 => :tag_fax_profile,
403 => :tag_coding_methods,
404 => :tag_version_year,
405 => :tag_mode_number,
433 => :tag_decode,
434 => :tag_default_image_color,
435 => :tag_t82_options,
437 => :tag_jpeg_tables2,
512 => :tag_jpeg_proc,
513 => :tag_thumbnail_offset,
514 => :tag_thumbnail_length,
515 => :tag_jpeg_restart_interval,
517 => :tag_jpeg_lossless_predictors,
518 => :tag_jpeg_point_transforms,
519 => :tag_jpegq_tables,
520 => :tag_jpegdc_tables,
521 => :tag_jpegac_tables,
529 => :tag_y_cb_cr_coefficients,
530 => :tag_y_cb_cr_sub_sampling,
531 => :tag_y_cb_cr_positioning,
532 => :tag_reference_black_white,
559 => :tag_strip_row_counts,
700 => :tag_application_notes,
999 => :tag_uspto_miscellaneous,
4096 => :tag_related_image_file_format,
4097 => :tag_related_image_width,
4098 => :tag_related_image_height,
18246 => :tag_rating,
18247 => :tag_xp_dip_xml,
18248 => :tag_stitch_info,
18249 => :tag_rating_percent,
28672 => :tag_sony_raw_file_type,
28722 => :tag_light_falloff_params,
28725 => :tag_chromatic_aberration_corr_params,
28727 => :tag_distortion_corr_params,
32781 => :tag_image_id,
32931 => :tag_wang_tag1,
32932 => :tag_wang_annotation,
32933 => :tag_wang_tag3,
32934 => :tag_wang_tag4,
32953 => :tag_image_reference_points,
32954 => :tag_region_xform_tack_point,
32955 => :tag_warp_quadrilateral,
32956 => :tag_affine_transform_mat,
32995 => :tag_matteing,
32996 => :tag_data_type,
32997 => :tag_image_depth,
32998 => :tag_tile_depth,
33300 => :tag_image_full_width,
33301 => :tag_image_full_height,
33302 => :tag_texture_format,
33303 => :tag_wrap_modes,
33304 => :tag_fov_cot,
33305 => :tag_matrix_world_to_screen,
33306 => :tag_matrix_world_to_camera,
33405 => :tag_model2,
33421 => :tag_cfa_repeat_pattern_dim,
33422 => :tag_cfa_pattern2,
33423 => :tag_battery_level,
33424 => :tag_kodak_ifd,
33432 => :tag_copyright,
33434 => :tag_exposure_time,
33437 => :tag_f_number,
33445 => :tag_md_file_tag,
33446 => :tag_md_scale_pixel,
33447 => :tag_md_color_table,
33448 => :tag_md_lab_name,
33449 => :tag_md_sample_info,
33450 => :tag_md_prep_date,
33451 => :tag_md_prep_time,
33452 => :tag_md_file_units,
33550 => :tag_pixel_scale,
33589 => :tag_advent_scale,
33590 => :tag_advent_revision,
33628 => :tag_uic1_tag,
33629 => :tag_uic2_tag,
33630 => :tag_uic3_tag,
33631 => :tag_uic4_tag,
33723 => :tag_iptc_naa,
33918 => :tag_intergraph_packet_data,
33919 => :tag_intergraph_flag_registers,
33920 => :tag_intergraph_matrix,
33921 => :tag_ingr_reserved,
33922 => :tag_model_tie_point,
34016 => :tag_site,
34017 => :tag_color_sequence,
34018 => :tag_it8_header,
34019 => :tag_raster_padding,
34020 => :tag_bits_per_run_length,
34021 => :tag_bits_per_extended_run_length,
34022 => :tag_color_table,
34023 => :tag_image_color_indicator,
34024 => :tag_background_color_indicator,
34025 => :tag_image_color_value,
34026 => :tag_background_color_value,
34027 => :tag_pixel_intensity_range,
34028 => :tag_transparency_indicator,
34029 => :tag_color_characterization,
34030 => :tag_hc_usage,
34031 => :tag_trap_indicator,
34032 => :tag_cmyk_equivalent,
34118 => :tag_sem_info,
34152 => :tag_afcp_iptc,
34232 => :tag_pixel_magic_jbig_options,
34263 => :tag_jpl_carto_ifd,
34264 => :tag_model_transform,
34306 => :tag_wb_grgb_levels,
34310 => :tag_leaf_data,
34377 => :tag_photoshop_settings,
34665 => :tag_exif_offset,
34675 => :tag_icc_profile,
34687 => :tag_tiff_fx_extensions,
34688 => :tag_multi_profiles,
34689 => :tag_shared_data,
34690 => :tag_t88_options,
34732 => :tag_image_layer,
34735 => :tag_geo_tiff_directory,
34736 => :tag_geo_tiff_double_params,
34737 => :tag_geo_tiff_ascii_params,
34750 => :tag_jbig_options,
34850 => :tag_exposure_program,
34852 => :tag_spectral_sensitivity,
34853 => :tag_gps_info,
34855 => :tag_iso,
34856 => :tag_opto_electric_conv_factor,
34857 => :tag_interlace,
34858 => :tag_time_zone_offset,
34859 => :tag_self_timer_mode,
34864 => :tag_sensitivity_type,
34865 => :tag_standard_output_sensitivity,
34866 => :tag_recommended_exposure_index,
34867 => :tag_iso_speed,
34868 => :tag_iso_speed_latitudeyyy,
34869 => :tag_iso_speed_latitudezzz,
34908 => :tag_fax_recv_params,
34909 => :tag_fax_sub_address,
34910 => :tag_fax_recv_time,
34929 => :tag_fedex_edr,
34954 => :tag_leaf_sub_ifd,
36864 => :tag_exif_version,
36867 => :tag_date_time_original,
36868 => :tag_create_date,
36873 => :tag_google_plus_upload_code,
36880 => :tag_offset_time,
36881 => :tag_offset_time_original,
36882 => :tag_offset_time_digitized,
37121 => :tag_components_configuration,
37122 => :tag_compressed_bits_per_pixel,
37377 => :tag_shutter_speed_value,
37378 => :tag_aperture_value,
37379 => :tag_brightness_value,
37380 => :tag_exposure_compensation,
37381 => :tag_max_aperture_value,
37382 => :tag_subject_distance,
37383 => :tag_metering_mode,
37384 => :tag_light_source,
37385 => :tag_flash,
37386 => :tag_focal_length,
37387 => :tag_flash_energy,
37388 => :tag_spatial_frequency_response,
37389 => :tag_noise,
37390 => :tag_focal_plane_x_resolution,
37391 => :tag_focal_plane_y_resolution,
37392 => :tag_focal_plane_resolution_unit,
37393 => :tag_image_number,
37394 => :tag_security_classification,
37395 => :tag_image_history,
37396 => :tag_subject_area,
37397 => :tag_exposure_index,
37398 => :tag_tiff_ep_standard_id,
37399 => :tag_sensing_method,
37434 => :tag_cip3_data_file,
37435 => :tag_cip3_sheet,
37436 => :tag_cip3_side,
37439 => :tag_sto_nits,
37500 => :tag_maker_note,
37510 => :tag_user_comment,
37520 => :tag_sub_sec_time,
37521 => :tag_sub_sec_time_original,
37522 => :tag_sub_sec_time_digitized,
37679 => :tag_ms_document_text,
37680 => :tag_ms_property_set_storage,
37681 => :tag_ms_document_text_position,
37724 => :tag_image_source_data,
37888 => :tag_ambient_temperature,
37889 => :tag_humidity,
37890 => :tag_pressure,
37891 => :tag_water_depth,
37892 => :tag_acceleration,
37893 => :tag_camera_elevation_angle,
40091 => :tag_xp_title,
40092 => :tag_xp_comment,
40093 => :tag_xp_author,
40094 => :tag_xp_keywords,
40095 => :tag_xp_subject,
40960 => :tag_flashpix_version,
40961 => :tag_color_space,
40962 => :tag_exif_image_width,
40963 => :tag_exif_image_height,
40964 => :tag_related_sound_file,
40965 => :tag_interop_offset,
40976 => :tag_samsung_raw_pointers_offset,
40977 => :tag_samsung_raw_pointers_length,
41217 => :tag_samsung_raw_byte_order,
41218 => :tag_samsung_raw_unknown,
41483 => :tag_flash_energy2,
41484 => :tag_spatial_frequency_response2,
41485 => :tag_noise2,
41486 => :tag_focal_plane_x_resolution2,
41487 => :tag_focal_plane_y_resolution2,
41488 => :tag_focal_plane_resolution_unit2,
41489 => :tag_image_number2,
41490 => :tag_security_classification2,
41491 => :tag_image_history2,
41492 => :tag_subject_location,
41493 => :tag_exposure_index2,
41494 => :tag_tiff_ep_standard_id2,
41495 => :tag_sensing_method2,
41728 => :tag_file_source,
41729 => :tag_scene_type,
41730 => :tag_cfa_pattern,
41985 => :tag_custom_rendered,
41986 => :tag_exposure_mode,
41987 => :tag_white_balance,
41988 => :tag_digital_zoom_ratio,
41989 => :tag_focal_length_in35mm_format,
41990 => :tag_scene_capture_type,
41991 => :tag_gain_control,
41992 => :tag_contrast,
41993 => :tag_saturation,
41994 => :tag_sharpness,
41995 => :tag_device_setting_description,
41996 => :tag_subject_distance_range,
42016 => :tag_image_unique_id,
42032 => :tag_owner_name,
42033 => :tag_serial_number,
42034 => :tag_lens_info,
42035 => :tag_lens_make,
42036 => :tag_lens_model,
42037 => :tag_lens_serial_number,
42112 => :tag_gdal_metadata,
42113 => :tag_gdal_no_data,
42240 => :tag_gamma,
44992 => :tag_expand_software,
44993 => :tag_expand_lens,
44994 => :tag_expand_film,
44995 => :tag_expand_filter_lens,
44996 => :tag_expand_scanner,
44997 => :tag_expand_flash_lamp,
48129 => :tag_pixel_format,
48130 => :tag_transformation,
48131 => :tag_uncompressed,
48132 => :tag_image_type,
48256 => :tag_image_width2,
48257 => :tag_image_height2,
48258 => :tag_width_resolution,
48259 => :tag_height_resolution,
48320 => :tag_image_offset,
48321 => :tag_image_byte_count,
48322 => :tag_alpha_offset,
48323 => :tag_alpha_byte_count,
48324 => :tag_image_data_discard,
48325 => :tag_alpha_data_discard,
50215 => :tag_oce_scanjob_desc,
50216 => :tag_oce_application_selector,
50217 => :tag_oce_id_number,
50218 => :tag_oce_image_logic,
50255 => :tag_annotations,
50341 => :tag_print_im,
50547 => :tag_original_file_name,
50560 => :tag_uspto_original_content_type,
50706 => :tag_dng_version,
50707 => :tag_dng_backward_version,
50708 => :tag_unique_camera_model,
50709 => :tag_localized_camera_model,
50710 => :tag_cfa_plane_color,
50711 => :tag_cfa_layout,
50712 => :tag_linearization_table,
50713 => :tag_black_level_repeat_dim,
50714 => :tag_black_level,
50715 => :tag_black_level_delta_h,
50716 => :tag_black_level_delta_v,
50717 => :tag_white_level,
50718 => :tag_default_scale,
50719 => :tag_default_crop_origin,
50720 => :tag_default_crop_size,
50721 => :tag_color_matrix1,
50722 => :tag_color_matrix2,
50723 => :tag_camera_calibration1,
50724 => :tag_camera_calibration2,
50725 => :tag_reduction_matrix1,
50726 => :tag_reduction_matrix2,
50727 => :tag_analog_balance,
50728 => :tag_as_shot_neutral,
50729 => :tag_as_shot_white_xy,
50730 => :tag_baseline_exposure,
50731 => :tag_baseline_noise,
50732 => :tag_baseline_sharpness,
50733 => :tag_bayer_green_split,
50734 => :tag_linear_response_limit,
50735 => :tag_camera_serial_number,
50736 => :tag_dng_lens_info,
50737 => :tag_chroma_blur_radius,
50738 => :tag_anti_alias_strength,
50739 => :tag_shadow_scale,
50740 => :tag_sr2_private,
50741 => :tag_maker_note_safety,
50752 => :tag_raw_image_segmentation,
50778 => :tag_calibration_illuminant1,
50779 => :tag_calibration_illuminant2,
50780 => :tag_best_quality_scale,
50781 => :tag_raw_data_unique_id,
50784 => :tag_alias_layer_metadata,
50827 => :tag_original_raw_file_name,
50828 => :tag_original_raw_file_data,
50829 => :tag_active_area,
50830 => :tag_masked_areas,
50831 => :tag_as_shot_icc_profile,
50832 => :tag_as_shot_pre_profile_matrix,
50833 => :tag_current_icc_profile,
50834 => :tag_current_pre_profile_matrix,
50879 => :tag_colorimetric_reference,
50885 => :tag_s_raw_type,
50898 => :tag_panasonic_title,
50899 => :tag_panasonic_title2,
50931 => :tag_camera_calibration_sig,
50932 => :tag_profile_calibration_sig,
50933 => :tag_profile_ifd,
50934 => :tag_as_shot_profile_name,
50935 => :tag_noise_reduction_applied,
50936 => :tag_profile_name,
50937 => :tag_profile_hue_sat_map_dims,
50938 => :tag_profile_hue_sat_map_data1,
50939 => :tag_profile_hue_sat_map_data2,
50940 => :tag_profile_tone_curve,
50941 => :tag_profile_embed_policy,
50942 => :tag_profile_copyright,
50964 => :tag_forward_matrix1,
50965 => :tag_forward_matrix2,
50966 => :tag_preview_application_name,
50967 => :tag_preview_application_version,
50968 => :tag_preview_settings_name,
50969 => :tag_preview_settings_digest,
50970 => :tag_preview_color_space,
50971 => :tag_preview_date_time,
50972 => :tag_raw_image_digest,
50973 => :tag_original_raw_file_digest,
50974 => :tag_sub_tile_block_size,
50975 => :tag_row_interleave_factor,
50981 => :tag_profile_look_table_dims,
50982 => :tag_profile_look_table_data,
51008 => :tag_opcode_list1,
51009 => :tag_opcode_list2,
51022 => :tag_opcode_list3,
51041 => :tag_noise_profile,
51043 => :tag_time_codes,
51044 => :tag_frame_rate,
51058 => :tag_t_stop,
51081 => :tag_reel_name,
51089 => :tag_original_default_final_size,
51090 => :tag_original_best_quality_size,
51091 => :tag_original_default_crop_size,
51105 => :tag_camera_label,
51107 => :tag_profile_hue_sat_map_encoding,
51108 => :tag_profile_look_table_encoding,
51109 => :tag_baseline_exposure_offset,
51110 => :tag_default_black_render,
51111 => :tag_new_raw_image_digest,
51112 => :tag_raw_to_preview_gain,
51125 => :tag_default_user_crop,
59932 => :tag_padding,
59933 => :tag_offset_schema,
65000 => :tag_owner_name2,
65001 => :tag_serial_number2,
65002 => :tag_lens,
65024 => :tag_kdc_ifd,
65100 => :tag_raw_file,
65101 => :tag_converter,
65102 => :tag_white_balance2,
65105 => :tag_exposure,
65106 => :tag_shadows,
65107 => :tag_brightness,
65108 => :tag_contrast2,
65109 => :tag_saturation2,
65110 => :tag_sharpness2,
65111 => :tag_smoothness,
65112 => :tag_moire_filter,
}
I__TAG = TAG.invert
def initialize(_io, _parent = nil, _root = nil)
super(_io, _parent, _root || self)
_read
end
def _read
@endianness = @_io.read_u2le
@body = ExifBody.new(@_io, self, @_root)
self
end
class ExifBody < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil)
super(_io, _parent, _root)
_read
end
def _read
case _root.endianness
when 18761
@_is_le = true
when 19789
@_is_le = false
end
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body")
end
self
end
def _read_le
@magic = @_io.read_u2le
raise Kaitai::Struct::ValidationNotEqualError.new(42, @magic, @_io, "/types/exif_body/seq/0") if not @magic == 42
@ofs_ifd0 = @_io.read_u4le
self
end
def _read_be
@magic = @_io.read_u2be
raise Kaitai::Struct::ValidationNotEqualError.new(42, @magic, @_io, "/types/exif_body/seq/0") if not @magic == 42
@ofs_ifd0 = @_io.read_u4be
self
end
class AsciiString < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/ascii_string")
end
self
end
def _read_le
@value = @_io.read_bytes_term(0, false, true, false)
self
end
def _read_be
@value = @_io.read_bytes_term(0, false, true, false)
self
end
##
# According to the core Exif standard, this should be ASCII, but in
# practice, this is not always the case. From
# [ExifTool FAQ](https://exiftool.sourceforge.net/faq.html#Q10):
#
# > However, it is not uncommon for applications to write UTF-8 or
# other encodings where ASCII is expected.
#
# Therefore, this field is a byte array, not a string. This is to
# avoid non-ASCII characters being treated as errors in some target
# languages, such as Python. The only assumption is that a null byte
# terminates the value (although sometimes the null byte is missing,
# which we tolerate thanks to the `eos-error: false` setting).
#
# Here is a sample JPEG file with a `tag::image_description` IFD
# field of type `field_type::ascii` that actually contains UTF-8:
# <https://github.com/Exiv2/exiv2/blob/2cd987a731236037b6b78cbff897d08685a8ef49/test/data/exiv2-bug501.jpg>
#
# It seems that most modern applications (e.g. GIMP 3.0.6) always
# use UTF-8 when storing Exif metadata. However, there are also
# files with a non-UTF-8 encoding, for example
# <https://github.com/drewnoakes/metadata-extractor-images/blob/651ad0e67aa8d43d358ad05f9bc07b52d8b9ac6e/jpg/Ricoh%20DC-3Z%20(low%20res).jpg>
# has a `tag::copyright` IFD field with a value encoded in
# ISO-8859-1 (Latin-1).
attr_reader :value
end
class Doubles < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/doubles")
end
self
end
def _read_le
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_f8le
}
self
end
def _read_be
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_f8be
}
self
end
attr_reader :values
end
class Floats < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/floats")
end
self
end
def _read_le
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_f4le
}
self
end
def _read_be
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_f4be
}
self
end
attr_reader :values
end
class Ifd < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil, is_gps_ifd)
super(_io, _parent, _root)
@_is_le = _is_le
@is_gps_ifd = is_gps_ifd
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/ifd")
end
self
end
def _read_le
@num_fields = @_io.read_u2le
@_raw_fields = []
@fields = []
(num_fields).times { |i|
_io_fields = @_io.substream(12)
@fields << IfdField.new(_io_fields, self, @_root, @_is_le)
}
@ofs_next_ifd = @_io.read_u4le
self
end
def _read_be
@num_fields = @_io.read_u2be
@_raw_fields = []
@fields = []
(num_fields).times { |i|
_io_fields = @_io.substream(12)
@fields << IfdField.new(_io_fields, self, @_root, @_is_le)
}
@ofs_next_ifd = @_io.read_u4be
self
end
def next_ifd
return @next_ifd unless @next_ifd.nil?
if ofs_next_ifd != 0
_pos = @_io.pos
@_io.seek(ofs_next_ifd)
if @_is_le
@next_ifd = Ifd.new(@_io, self, @_root, @_is_le, is_gps_ifd)
else
@next_ifd = Ifd.new(@_io, self, @_root, @_is_le, is_gps_ifd)
end
@_io.seek(_pos)
end
@next_ifd
end
attr_reader :num_fields
attr_reader :fields
attr_reader :ofs_next_ifd
attr_reader :is_gps_ifd
attr_reader :_raw_fields
end
class IfdField < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/ifd_field")
end
self
end
def _read_le
@tag_raw = @_io.read_u2le
@field_type = Kaitai::Struct::Stream::resolve_enum(Exif::FIELD_TYPE, @_io.read_u2le)
@num_values = @_io.read_u4le
if !(has_immediate_data)
@ofs_data = @_io.read_u4le
end
self
end
def _read_be
@tag_raw = @_io.read_u2be
@field_type = Kaitai::Struct::Stream::resolve_enum(Exif::FIELD_TYPE, @_io.read_u2be)
@num_values = @_io.read_u4be
if !(has_immediate_data)
@ofs_data = @_io.read_u4be
end
self
end
##
# Size in bytes of a single value of type `field_type`, or 0 if
# `field_type` is not one of the known types (in which case the size
# cannot be determined and `data` will be empty).
# @see https://www.media.mit.edu/pia/Research/deepview/exif.html#DataForm Source
def bytes_per_value
return @bytes_per_value unless @bytes_per_value.nil?
@bytes_per_value = ( ((field_type == :field_type_byte) || (field_type == :field_type_ascii) || (field_type == :field_type_sbyte) || (field_type == :field_type_undefined) || (field_type == :field_type_utf8)) ? 1 : ( ((field_type == :field_type_short) || (field_type == :field_type_sshort)) ? 2 : ( ((field_type == :field_type_long) || (field_type == :field_type_slong) || (field_type == :field_type_float) || (field_type == :field_type_ifd)) ? 4 : ( ((field_type == :field_type_rational) || (field_type == :field_type_srational) || (field_type == :field_type_double)) ? 8 : 0))))
@bytes_per_value
end
def data
return @data unless @data.nil?
io = (has_immediate_data ? _io : _root._io)
_pos = io.pos
io.seek((has_immediate_data ? 8 : ofs_data))
if @_is_le
case field_type
when :field_type_ascii
_io_data = io.substream(len_data)
@data = AsciiString.new(_io_data, self, @_root, @_is_le)
when :field_type_double
_io_data = io.substream(len_data)
@data = Doubles.new(_io_data, self, @_root, @_is_le)
when :field_type_float
_io_data = io.substream(len_data)
@data = Floats.new(_io_data, self, @_root, @_is_le)
when :field_type_ifd
_io_data = io.substream(len_data)
@data = Longs.new(_io_data, self, @_root, @_is_le)
when :field_type_long
_io_data = io.substream(len_data)
@data = Longs.new(_io_data, self, @_root, @_is_le)
when :field_type_rational
_io_data = io.substream(len_data)
@data = Rationals.new(_io_data, self, @_root, @_is_le)
when :field_type_sbyte
_io_data = io.substream(len_data)
@data = Sbytes.new(_io_data, self, @_root, @_is_le)
when :field_type_short
_io_data = io.substream(len_data)
@data = Shorts.new(_io_data, self, @_root, @_is_le)
when :field_type_slong
_io_data = io.substream(len_data)
@data = Slongs.new(_io_data, self, @_root, @_is_le)
when :field_type_srational
_io_data = io.substream(len_data)
@data = Srationals.new(_io_data, self, @_root, @_is_le)
when :field_type_sshort
_io_data = io.substream(len_data)
@data = Sshorts.new(_io_data, self, @_root, @_is_le)
when :field_type_utf8
_io_data = io.substream(len_data)
@data = Utf8String.new(_io_data, self, @_root, @_is_le)
else
@data = io.read_bytes(len_data)
end
else
case field_type
when :field_type_ascii
_io_data = io.substream(len_data)
@data = AsciiString.new(_io_data, self, @_root, @_is_le)
when :field_type_double
_io_data = io.substream(len_data)
@data = Doubles.new(_io_data, self, @_root, @_is_le)
when :field_type_float
_io_data = io.substream(len_data)
@data = Floats.new(_io_data, self, @_root, @_is_le)
when :field_type_ifd
_io_data = io.substream(len_data)
@data = Longs.new(_io_data, self, @_root, @_is_le)
when :field_type_long
_io_data = io.substream(len_data)
@data = Longs.new(_io_data, self, @_root, @_is_le)
when :field_type_rational
_io_data = io.substream(len_data)
@data = Rationals.new(_io_data, self, @_root, @_is_le)
when :field_type_sbyte
_io_data = io.substream(len_data)
@data = Sbytes.new(_io_data, self, @_root, @_is_le)
when :field_type_short
_io_data = io.substream(len_data)
@data = Shorts.new(_io_data, self, @_root, @_is_le)
when :field_type_slong
_io_data = io.substream(len_data)
@data = Slongs.new(_io_data, self, @_root, @_is_le)
when :field_type_srational
_io_data = io.substream(len_data)
@data = Srationals.new(_io_data, self, @_root, @_is_le)
when :field_type_sshort
_io_data = io.substream(len_data)
@data = Sshorts.new(_io_data, self, @_root, @_is_le)
when :field_type_utf8
_io_data = io.substream(len_data)
@data = Utf8String.new(_io_data, self, @_root, @_is_le)
else
@data = io.read_bytes(len_data)
end
end
io.seek(_pos)
@data
end
def gps_tag
return @gps_tag unless @gps_tag.nil?
if _parent.is_gps_ifd
@gps_tag = Kaitai::Struct::Stream::resolve_enum(Exif::GPS_TAG, tag_raw)
end
@gps_tag
end
def has_immediate_data
return @has_immediate_data unless @has_immediate_data.nil?
@has_immediate_data = len_data <= 4
@has_immediate_data
end
def len_data
return @len_data unless @len_data.nil?
@len_data = bytes_per_value * num_values
@len_data
end
##
# All the "IFD Pointer" tags (as the core Exif standard calls them),
# i.e. `ExifOffset`, `InteropOffset` and `GPSInfo` (using the
# [ExifTool's
# names](https://exiftool.sourceforge.net/TagNames/EXIF.html)),
# should be of type `LONG` (`field_type::long`). However, the type
# `SLONG` (`field_type::slong`) type has also been observed:
# <https://github.com/Exiv2/exiv2/blob/2cd987a731236037b6b78cbff897d08685a8ef49/test/data/FurnaceCreekInn.jpg>
#
# Both ExifTool and Exiv2 accept `LONG`, `SLONG` and also `IFD`.
# Exiv2 specifically supports only these three types - see
# <https://github.com/Exiv2/exiv2/blob/2cd987a731236037b6b78cbff897d08685a8ef49/src/tiffvisitor_int.cpp#L1141>
# (Git tag "v0.28.8"). ExifTool is more lenient - it even accepts
# any integer type. In practice, real files most likely only use one
# of the three types supported by Exiv2, so we stick with that.
def sub_ifd
return @sub_ifd unless @sub_ifd.nil?
if ((num_values == 1) && ( ((field_type == :field_type_long) || (field_type == :field_type_ifd) || ( ((field_type == :field_type_slong) && (data.values.first >= 0)) )) ) && ( ((tag == :tag_exif_offset) || (tag == :tag_interop_offset) || (tag == :tag_gps_info)) ))
io = _root._io
_pos = io.pos
io.seek((field_type == :field_type_slong ? data.values.first : data.values.first))
if @_is_le
@sub_ifd = Ifd.new(io, self, @_root, @_is_le, tag == :tag_gps_info)
else
@sub_ifd = Ifd.new(io, self, @_root, @_is_le, tag == :tag_gps_info)
end
io.seek(_pos)
end
@sub_ifd
end
def tag
return @tag unless @tag.nil?
if !(_parent.is_gps_ifd)
@tag = Kaitai::Struct::Stream::resolve_enum(Exif::TAG, tag_raw)
end
@tag
end
##
# Raw numeric tag. Don't read this field - access `tag` or `gps_tag`
# instead.
attr_reader :tag_raw
attr_reader :field_type
attr_reader :num_values
attr_reader :ofs_data
attr_reader :_raw_data
end
class Longs < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/longs")
end
self
end
def _read_le
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_u4le
}
self
end
def _read_be
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_u4be
}
self
end
attr_reader :values
end
class Rational < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/rational")
end
self
end
def _read_le
@value_num = @_io.read_u4le
@value_den = @_io.read_u4le
self
end
def _read_be
@value_num = @_io.read_u4be
@value_den = @_io.read_u4be
self
end
##
# If denominator is zero, this instance is disabled to prevent
# `ZeroDivisionError` in Python.
#
# Here's a sample file with a zero denominator in the IFD fields
# `tag::x_resolution` and `tag::y_resolution` (both of which are of
# type `field_type::rational`):
# <https://github.com/python-pillow/Pillow/blob/807d689a83738027b6f6e0f219a6a6dd30e01c08/Tests/images/exif-dpi-zerodivision.jpg>
def value
return @value unless @value.nil?
if value_den != 0
@value = (value_num + 0.0) / value_den
end
@value
end
##
# Numerator
attr_reader :value_num
##
# Denominator
attr_reader :value_den
end
class Rationals < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/rationals")
end
self
end
def _read_le
@values = []
(_parent.num_values).times { |i|
@values << Rational.new(@_io, self, @_root, @_is_le)
}
self
end
def _read_be
@values = []
(_parent.num_values).times { |i|
@values << Rational.new(@_io, self, @_root, @_is_le)
}
self
end
attr_reader :values
end
class Sbytes < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/sbytes")
end
self
end
def _read_le
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_s1
}
self
end
def _read_be
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_s1
}
self
end
attr_reader :values
end
class Shorts < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/shorts")
end
self
end
def _read_le
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_u2le
}
self
end
def _read_be
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_u2be
}
self
end
attr_reader :values
end
class Slongs < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/slongs")
end
self
end
def _read_le
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_s4le
}
self
end
def _read_be
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_s4be
}
self
end
attr_reader :values
end
class Srational < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/srational")
end
self
end
def _read_le
@value_num = @_io.read_s4le
@value_den = @_io.read_s4le
self
end
def _read_be
@value_num = @_io.read_s4be
@value_den = @_io.read_s4be
self
end
##
# If denominator is zero, this instance is disabled to prevent
# `ZeroDivisionError` in Python.
#
# Here's a sample file with a zero denominator in the IFD field
# `tag::exposure_compensation` of type `field_type::srational`:
# <https://github.com/drewnoakes/metadata-extractor-images/blob/651ad0e67aa8d43d358ad05f9bc07b52d8b9ac6e/jpg/Reconyx%20Hyperfire%20HP4K.jpg>
def value
return @value unless @value.nil?
if value_den != 0
@value = (value_num + 0.0) / value_den
end
@value
end
##
# Numerator
attr_reader :value_num
##
# Denominator
attr_reader :value_den
end
class Srationals < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/srationals")
end
self
end
def _read_le
@values = []
(_parent.num_values).times { |i|
@values << Srational.new(@_io, self, @_root, @_is_le)
}
self
end
def _read_be
@values = []
(_parent.num_values).times { |i|
@values << Srational.new(@_io, self, @_root, @_is_le)
}
self
end
attr_reader :values
end
class Sshorts < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/sshorts")
end
self
end
def _read_le
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_s2le
}
self
end
def _read_be
@values = []
(_parent.num_values).times { |i|
@values << @_io.read_s2be
}
self
end
attr_reader :values
end
class Utf8String < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = nil, _is_le = nil)
super(_io, _parent, _root)
@_is_le = _is_le
_read
end
def _read
if @_is_le == true
_read_le
elsif @_is_le == false
_read_be
else
raise Kaitai::Struct::UndecidedEndiannessError.new("/types/exif_body/types/utf8_string")
end
self
end
def _read_le
@value = (@_io.read_bytes_term(0, false, true, false)).force_encoding("UTF-8")
self
end
def _read_be
@value = (@_io.read_bytes_term(0, false, true, false)).force_encoding("UTF-8")
self
end
attr_reader :value
end
def ifd0
return @ifd0 unless @ifd0.nil?
_pos = @_io.pos
@_io.seek(ofs_ifd0)
if @_is_le
@ifd0 = Ifd.new(@_io, self, @_root, @_is_le, false)
else
@ifd0 = Ifd.new(@_io, self, @_root, @_is_le, false)
end
@_io.seek(_pos)
@ifd0
end
attr_reader :magic
attr_reader :ofs_ifd0
end
attr_reader :endianness
attr_reader :body
end