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author | 2024-08-02 11:46:41 +0000 | |
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committer | 2024-08-02 12:46:41 +0100 | |
commit | 94e87610c4ce9bbb1c614a61bab29c1422fed11b (patch) | |
tree | 2e06b8ce64212140e796f6077ba841b6cc678501 /vendor/codeberg.org/superseriousbusiness/exif-terminator/jpeg.go | |
parent | [feature] Allow import of following and blocks via CSV (#3150) (diff) | |
download | gotosocial-94e87610c4ce9bbb1c614a61bab29c1422fed11b.tar.xz |
[chore] add back exif-terminator and use only for jpeg,png,webp (#3161)
* add back exif-terminator and use only for jpeg,png,webp
* fix arguments passed to terminateExif()
* pull in latest exif-terminator
* fix test
* update processed img
---------
Co-authored-by: tobi <tobi.smethurst@protonmail.com>
Diffstat (limited to 'vendor/codeberg.org/superseriousbusiness/exif-terminator/jpeg.go')
-rw-r--r-- | vendor/codeberg.org/superseriousbusiness/exif-terminator/jpeg.go | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/vendor/codeberg.org/superseriousbusiness/exif-terminator/jpeg.go b/vendor/codeberg.org/superseriousbusiness/exif-terminator/jpeg.go new file mode 100644 index 000000000..3c8b7035f --- /dev/null +++ b/vendor/codeberg.org/superseriousbusiness/exif-terminator/jpeg.go @@ -0,0 +1,132 @@ +/* + exif-terminator + Copyright (C) 2022 SuperSeriousBusiness admin@gotosocial.org + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU Affero General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program 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 Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +package terminator + +import ( + "encoding/binary" + "fmt" + "io" + + jpegstructure "github.com/superseriousbusiness/go-jpeg-image-structure/v2" +) + +var markerLen = map[byte]int{ + 0x00: 0, + 0x01: 0, + 0xd0: 0, + 0xd1: 0, + 0xd2: 0, + 0xd3: 0, + 0xd4: 0, + 0xd5: 0, + 0xd6: 0, + 0xd7: 0, + 0xd8: 0, + 0xd9: 0, + 0xda: 0, + + // J2C + 0x30: 0, + 0x31: 0, + 0x32: 0, + 0x33: 0, + 0x34: 0, + 0x35: 0, + 0x36: 0, + 0x37: 0, + 0x38: 0, + 0x39: 0, + 0x3a: 0, + 0x3b: 0, + 0x3c: 0, + 0x3d: 0, + 0x3e: 0, + 0x3f: 0, + 0x4f: 0, + 0x92: 0, + 0x93: 0, + + // J2C extensions + 0x74: 4, + 0x75: 4, + 0x77: 4, +} + +type jpegVisitor struct { + js *jpegstructure.JpegSplitter + writer io.Writer +} + +// HandleSegment satisfies the visitor interface{} of the jpegstructure library. +// +// We don't really care about many of the parameters, since all we're interested +// in here is the very last segment that was scanned. +func (v *jpegVisitor) HandleSegment(segmentMarker byte, _ string, _ int, _ bool) error { + segmentList := v.js.Segments() + segments := segmentList.Segments() + mostRecentSegment := segments[len(segments)-1] + return v.writeSegment(mostRecentSegment) +} + +func (v *jpegVisitor) writeSegment(s *jpegstructure.Segment) error { + w := v.writer + + defer func() { + // whatever happens, when we finished then evict data from the segment; + // once we've written it we don't want it in memory anymore + s.Data = nil + }() + + if s.IsExif() { + // Segment contains exif data, terminate! + if err := terminateEXIF(s); err != nil { + return err + } + } + + // The scan-data will have a marker-ID of (0) because it doesn't have a marker-ID or length. + if s.MarkerId != 0 { + _, err := w.Write([]byte{0xff, s.MarkerId}) + if err != nil { + return err + } + + sizeLen, found := markerLen[s.MarkerId] + if !found || sizeLen == 2 { + sizeLen = 2 + l := uint16(len(s.Data) + sizeLen) + + if err := binary.Write(w, binary.BigEndian, &l); err != nil { + return err + } + + } else if sizeLen == 4 { + l := uint32(len(s.Data) + sizeLen) + + if err := binary.Write(w, binary.BigEndian, &l); err != nil { + return err + } + } else if sizeLen != 0 { + return fmt.Errorf("not a supported marker-size: MARKER-ID=(0x%02x) MARKER-SIZE-LEN=(%d)", s.MarkerId, sizeLen) + } + } + + _, err := w.Write(s.Data) + return err +} |