| /* |
| * EXIF metadata parser |
| * Copyright (c) 2013 Thilo Borgmann <thilo.borgmann _at_ mail.de> |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * EXIF metadata parser |
| * @author Thilo Borgmann <thilo.borgmann _at_ mail.de> |
| */ |
| |
| #include "exif.h" |
| #include "tiff_common.h" |
| |
| #define EXIF_TAG_NAME_LENGTH 32 |
| |
| struct exif_tag { |
| char name[EXIF_TAG_NAME_LENGTH]; |
| uint16_t id; |
| }; |
| |
| static const struct exif_tag tag_list[] = { // JEITA CP-3451 EXIF specification: |
| {"GPSVersionID", 0x00}, // <- Table 12 GPS Attribute Information |
| {"GPSLatitudeRef", 0x01}, |
| {"GPSLatitude", 0x02}, |
| {"GPSLongitudeRef", 0x03}, |
| {"GPSLongitude", 0x04}, |
| {"GPSAltitudeRef", 0x05}, |
| {"GPSAltitude", 0x06}, |
| {"GPSTimeStamp", 0x07}, |
| {"GPSSatellites", 0x08}, |
| {"GPSStatus", 0x09}, |
| {"GPSMeasureMode", 0x0A}, |
| {"GPSDOP", 0x0B}, |
| {"GPSSpeedRef", 0x0C}, |
| {"GPSSpeed", 0x0D}, |
| {"GPSTrackRef", 0x0E}, |
| {"GPSTrack", 0x0F}, |
| {"GPSImgDirectionRef", 0x10}, |
| {"GPSImgDirection", 0x11}, |
| {"GPSMapDatum", 0x12}, |
| {"GPSDestLatitudeRef", 0x13}, |
| {"GPSDestLatitude", 0x14}, |
| {"GPSDestLongitudeRef", 0x15}, |
| {"GPSDestLongitude", 0x16}, |
| {"GPSDestBearingRef", 0x17}, |
| {"GPSDestBearing", 0x18}, |
| {"GPSDestDistanceRef", 0x19}, |
| {"GPSDestDistance", 0x1A}, |
| {"GPSProcessingMethod", 0x1B}, |
| {"GPSAreaInformation", 0x1C}, |
| {"GPSDateStamp", 0x1D}, |
| {"GPSDifferential", 0x1E}, |
| {"ImageWidth", 0x100}, // <- Table 3 TIFF Rev. 6.0 Attribute Information Used in Exif |
| {"ImageLength", 0x101}, |
| {"BitsPerSample", 0x102}, |
| {"Compression", 0x103}, |
| {"PhotometricInterpretation", 0x106}, |
| {"Orientation", 0x112}, |
| {"SamplesPerPixel", 0x115}, |
| {"PlanarConfiguration", 0x11C}, |
| {"YCbCrSubSampling", 0x212}, |
| {"YCbCrPositioning", 0x213}, |
| {"XResolution", 0x11A}, |
| {"YResolution", 0x11B}, |
| {"ResolutionUnit", 0x128}, |
| {"StripOffsets", 0x111}, |
| {"RowsPerStrip", 0x116}, |
| {"StripByteCounts", 0x117}, |
| {"JPEGInterchangeFormat", 0x201}, |
| {"JPEGInterchangeFormatLength",0x202}, |
| {"TransferFunction", 0x12D}, |
| {"WhitePoint", 0x13E}, |
| {"PrimaryChromaticities", 0x13F}, |
| {"YCbCrCoefficients", 0x211}, |
| {"ReferenceBlackWhite", 0x214}, |
| {"DateTime", 0x132}, |
| {"ImageDescription", 0x10E}, |
| {"Make", 0x10F}, |
| {"Model", 0x110}, |
| {"Software", 0x131}, |
| {"Artist", 0x13B}, |
| {"Copyright", 0x8298}, |
| {"ExifVersion", 0x9000}, // <- Table 4 Exif IFD Attribute Information (1) |
| {"FlashpixVersion", 0xA000}, |
| {"ColorSpace", 0xA001}, |
| {"ComponentsConfiguration", 0x9101}, |
| {"CompressedBitsPerPixel", 0x9102}, |
| {"PixelXDimension", 0xA002}, |
| {"PixelYDimension", 0xA003}, |
| {"MakerNote", 0x927C}, |
| {"UserComment", 0x9286}, |
| {"RelatedSoundFile", 0xA004}, |
| {"DateTimeOriginal", 0x9003}, |
| {"DateTimeDigitized", 0x9004}, |
| {"SubSecTime", 0x9290}, |
| {"SubSecTimeOriginal", 0x9291}, |
| {"SubSecTimeDigitized", 0x9292}, |
| {"ImageUniqueID", 0xA420}, |
| {"ExposureTime", 0x829A}, // <- Table 5 Exif IFD Attribute Information (2) |
| {"FNumber", 0x829D}, |
| {"ExposureProgram", 0x8822}, |
| {"SpectralSensitivity", 0x8824}, |
| {"ISOSpeedRatings", 0x8827}, |
| {"OECF", 0x8828}, |
| {"ShutterSpeedValue", 0x9201}, |
| {"ApertureValue", 0x9202}, |
| {"BrightnessValue", 0x9203}, |
| {"ExposureBiasValue", 0x9204}, |
| {"MaxApertureValue", 0x9205}, |
| {"SubjectDistance", 0x9206}, |
| {"MeteringMode", 0x9207}, |
| {"LightSource", 0x9208}, |
| {"Flash", 0x9209}, |
| {"FocalLength", 0x920A}, |
| {"SubjectArea", 0x9214}, |
| {"FlashEnergy", 0xA20B}, |
| {"SpatialFrequencyResponse", 0xA20C}, |
| {"FocalPlaneXResolution", 0xA20E}, |
| {"FocalPlaneYResolution", 0xA20F}, |
| {"FocalPlaneResolutionUnit", 0xA210}, |
| {"SubjectLocation", 0xA214}, |
| {"ExposureIndex", 0xA215}, |
| {"SensingMethod", 0xA217}, |
| {"FileSource", 0xA300}, |
| {"SceneType", 0xA301}, |
| {"CFAPattern", 0xA302}, |
| {"CustomRendered", 0xA401}, |
| {"ExposureMode", 0xA402}, |
| {"WhiteBalance", 0xA403}, |
| {"DigitalZoomRatio", 0xA404}, |
| {"FocalLengthIn35mmFilm", 0xA405}, |
| {"SceneCaptureType", 0xA406}, |
| {"GainControl", 0xA407}, |
| {"Contrast", 0xA408}, |
| {"Saturation", 0xA409}, |
| {"Sharpness", 0xA40A}, |
| {"DeviceSettingDescription", 0xA40B}, |
| {"SubjectDistanceRange", 0xA40C} |
| // {"InteroperabilityIndex", 0x1}, // <- Table 13 Interoperability IFD Attribute Information |
| }; |
| |
| static const char *exif_get_tag_name(uint16_t id) |
| { |
| int i; |
| |
| for (i = 0; i < FF_ARRAY_ELEMS(tag_list); i++) { |
| if (tag_list[i].id == id) |
| return tag_list[i].name; |
| } |
| |
| return NULL; |
| } |
| |
| |
| static int exif_add_metadata(void *logctx, int count, int type, |
| const char *name, const char *sep, |
| GetByteContext *gb, int le, |
| AVDictionary **metadata) |
| { |
| switch(type) { |
| case 0: |
| av_log(logctx, AV_LOG_WARNING, |
| "Invalid TIFF tag type 0 found for %s with size %d\n", |
| name, count); |
| return 0; |
| case TIFF_DOUBLE : return ff_tadd_doubles_metadata(count, name, sep, gb, le, metadata); |
| case TIFF_SSHORT : return ff_tadd_shorts_metadata(count, name, sep, gb, le, 1, metadata); |
| case TIFF_SHORT : return ff_tadd_shorts_metadata(count, name, sep, gb, le, 0, metadata); |
| case TIFF_SBYTE : return ff_tadd_bytes_metadata(count, name, sep, gb, le, 1, metadata); |
| case TIFF_BYTE : |
| case TIFF_UNDEFINED: return ff_tadd_bytes_metadata(count, name, sep, gb, le, 0, metadata); |
| case TIFF_STRING : return ff_tadd_string_metadata(count, name, gb, le, metadata); |
| case TIFF_SRATIONAL: |
| case TIFF_RATIONAL : return ff_tadd_rational_metadata(count, name, sep, gb, le, metadata); |
| case TIFF_SLONG : |
| case TIFF_LONG : return ff_tadd_long_metadata(count, name, sep, gb, le, metadata); |
| default: |
| avpriv_request_sample(logctx, "TIFF tag type (%u)", type); |
| return 0; |
| }; |
| } |
| |
| |
| static int exif_decode_tag(void *logctx, GetByteContext *gbytes, int le, |
| int depth, AVDictionary **metadata) |
| { |
| int ret, cur_pos; |
| unsigned id, count; |
| enum TiffTypes type; |
| |
| if (depth > 2) { |
| return 0; |
| } |
| |
| ff_tread_tag(gbytes, le, &id, &type, &count, &cur_pos); |
| |
| if (!bytestream2_tell(gbytes)) { |
| bytestream2_seek(gbytes, cur_pos, SEEK_SET); |
| return 0; |
| } |
| |
| // read count values and add it metadata |
| // store metadata or proceed with next IFD |
| ret = ff_tis_ifd(id); |
| if (ret) { |
| ret = ff_exif_decode_ifd(logctx, gbytes, le, depth + 1, metadata); |
| } else { |
| const char *name = exif_get_tag_name(id); |
| char buf[7]; |
| |
| if (!name) { |
| name = buf; |
| snprintf(buf, sizeof(buf), "0x%04X", id); |
| } |
| |
| ret = exif_add_metadata(logctx, count, type, name, NULL, |
| gbytes, le, metadata); |
| } |
| |
| bytestream2_seek(gbytes, cur_pos, SEEK_SET); |
| |
| return ret; |
| } |
| |
| |
| int ff_exif_decode_ifd(void *logctx, GetByteContext *gbytes, |
| int le, int depth, AVDictionary **metadata) |
| { |
| int i, ret; |
| int entries; |
| |
| entries = ff_tget_short(gbytes, le); |
| |
| if (bytestream2_get_bytes_left(gbytes) < entries * 12) { |
| return AVERROR_INVALIDDATA; |
| } |
| |
| for (i = 0; i < entries; i++) { |
| if ((ret = exif_decode_tag(logctx, gbytes, le, depth, metadata)) < 0) { |
| return ret; |
| } |
| } |
| |
| // return next IDF offset or 0x000000000 or a value < 0 for failure |
| return ff_tget_long(gbytes, le); |
| } |
| |
| int avpriv_exif_decode_ifd(void *logctx, const uint8_t *buf, int size, |
| int le, int depth, AVDictionary **metadata) |
| { |
| GetByteContext gb; |
| |
| bytestream2_init(&gb, buf, size); |
| |
| return ff_exif_decode_ifd(logctx, &gb, le, depth, metadata); |
| } |
