diff options
| -rw-r--r-- | internal/media/metadata.go | 2 | ||||
| -rw-r--r-- | internal/media/probe.go | 283 | ||||
| -rw-r--r-- | internal/media/processingemoji.go | 2 | ||||
| -rw-r--r-- | internal/media/processingmedia.go | 2 |
4 files changed, 286 insertions, 3 deletions
diff --git a/internal/media/metadata.go b/internal/media/metadata.go index e9256f1b1..e8eb32c0d 100644 --- a/internal/media/metadata.go +++ b/internal/media/metadata.go @@ -73,7 +73,7 @@ func clearMetadata(ctx context.Context, filepath string) error { } // terminateExif cleans exif data from file at input path, into file -// at output path, exusing given file extension to determine cleaning. +// at output path, using given file extension to determine cleaning type. func terminateExif(outpath, inpath string, ext string) error { // Open input file at given path. inFile, err := os.Open(inpath) diff --git a/internal/media/probe.go b/internal/media/probe.go new file mode 100644 index 000000000..882a2981d --- /dev/null +++ b/internal/media/probe.go @@ -0,0 +1,283 @@ +// GoToSocial +// Copyright (C) GoToSocial Authors admin@gotosocial.org +// SPDX-License-Identifier: AGPL-3.0-or-later +// +// 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 media + +import ( + "context" + "encoding/binary" + "image/jpeg" + "io" + "os" + "strings" + + "codeberg.org/gruf/go-byteutil" + "github.com/superseriousbusiness/gotosocial/internal/gtserror" + "github.com/superseriousbusiness/gotosocial/internal/log" +) + +const ( + // image magic header bytes. + magicJPEG = "\xff\xd8\xff" +) + +// probe will first attempt to probe the file at path using native Go code +// (for performance), but falls back to using ffprobe to retrieve media details. +func probe(ctx context.Context, filepath string) (*result, error) { + // Open input file at given path. + file, err := os.Open(filepath) + if err != nil { + return nil, gtserror.Newf("error opening file %s: %w", filepath, err) + } + + // Close on return. + defer file.Close() + + // Byte buf to check for + // file header magic bytes. + buf := make([]byte, 3) + + // Read file header into buffer. + _, err = io.ReadFull(file, buf) + if err != nil { + return nil, gtserror.Newf("error reading file %s: %w", filepath, err) + } + + switch { + // Attempt to probe JPEG types + // separately, to save calls into + // WebAssembly for a common image. + case string(buf[:len(magicJPEG)]) == magicJPEG: + log.Debug(ctx, "probing jpeg") + return probeJPEG(file) + + default: + // Close BEFORE + // pass to ffprobe. + _ = file.Close() + + // For everything else, fall back + // to calling ffprobe on input file. + log.Debug(ctx, "ffprobing file") + return ffprobe(ctx, filepath) + } +} + +// probeJPEG decodes the given file as JPEG and determines +// image details from the decoded JPEG using native Go code. +func probeJPEG(file *os.File) (*result, error) { + // Attempt to decode JPEG, adding back hdr magic. + cfg, err := jpeg.DecodeConfig(io.MultiReader( + strings.NewReader(magicJPEG), + file, + )) + if err != nil { + return nil, gtserror.Newf("error decoding file %s: %w", file.Name(), err) + } + + // Jump back to file start. + _, err = file.Seek(0, 0) + if err != nil { + return nil, gtserror.Newf("error seeking in file %s: %w", file.Name(), err) + } + + // Read orientation data from EXIF. + orientation := readOrientation(file) + + // Setup result as if + // ffprobe'd resulting in + // JPEG file container. + var res result + res.format = "image2" + + // Set image orientation data. + res.orientation = orientation + + // Extract image details. + res.video = []videoStream{{ + stream: stream{codec: "mjpeg"}, + width: cfg.Width, + height: cfg.Height, + + // setting a pixel color format + // doesn't matter for JPEG, as we + // don't bother even using it. + pixfmt: "", + }} + + return &res, nil +} + +// readOrientation reads orientation EXIF +// data (if it even exists) from image file. +// +// copied from github.com/disintegration/imaging +// but modified to optimize discard operations. +func readOrientation(r *os.File) int { + const ( + markerAPP1 = 0xffe1 + exifHeader = 0x45786966 + byteOrderBE = 0x4d4d + byteOrderLE = 0x4949 + orientationTag = 0x0112 + ) + + // Setup a discard read buffer. + buf := new(byteutil.Buffer) + buf.Guarantee(32) + + // discard simply reads into buf. + discard := func(n int) error { + buf.Guarantee(n) // ensure big enough + _, err := io.ReadFull(r, buf.B[:n]) + return err + } + + // Skip past JPEG SOI marker. + if err := discard(2); err != nil { + return orientationUnspecified + } + + // Find JPEG + // APP1 marker. + for { + var marker, size uint16 + + if err := binary.Read(r, binary.BigEndian, &marker); err != nil { + return orientationUnspecified + } + + if err := binary.Read(r, binary.BigEndian, &size); err != nil { + return orientationUnspecified + } + + if marker>>8 != 0xff { + return orientationUnspecified // Invalid JPEG marker. + } + + if marker == markerAPP1 { + break + } + + if size < 2 { + return orientationUnspecified // Invalid block size. + } + + if err := discard(int(size - 2)); err != nil { + return orientationUnspecified + } + } + + // Check if EXIF + // header is present. + var header uint32 + + if err := binary.Read(r, binary.BigEndian, &header); err != nil { + return orientationUnspecified + } + + if header != exifHeader { + return orientationUnspecified + } + + if err := discard(2); err != nil { + return orientationUnspecified + } + + // Read byte + // order info. + var ( + byteOrderTag uint16 + byteOrder binary.ByteOrder + ) + + if err := binary.Read(r, binary.BigEndian, &byteOrderTag); err != nil { + return orientationUnspecified + } + + switch byteOrderTag { + case byteOrderBE: + byteOrder = binary.BigEndian + case byteOrderLE: + byteOrder = binary.LittleEndian + default: + return orientationUnspecified // Invalid byte order flag. + } + + if err := discard(2); err != nil { + return orientationUnspecified + } + + // Skip the + // EXIF offset. + var offset uint32 + + if err := binary.Read(r, byteOrder, &offset); err != nil { + return orientationUnspecified + } + + if offset < 8 { + return orientationUnspecified // Invalid offset value. + } + + if err := discard(int(offset - 8)); err != nil { + return orientationUnspecified + } + + // Read the + // number of tags. + var numTags uint16 + + if err := binary.Read(r, byteOrder, &numTags); err != nil { + return orientationUnspecified + } + + // Find the orientation tag. + for i := 0; i < int(numTags); i++ { + var tag uint16 + + if err := binary.Read(r, byteOrder, &tag); err != nil { + return orientationUnspecified + } + + if tag != orientationTag { + if err := discard(10); err != nil { + return orientationUnspecified + } + continue + } + + if err := discard(6); err != nil { + return orientationUnspecified + } + + var val uint16 + + if err := binary.Read(r, byteOrder, &val); err != nil { + return orientationUnspecified + } + + if val < 1 || val > 8 { + return orientationUnspecified // Invalid tag value. + } + + return int(val) + } + + // Missing orientation tag. + return orientationUnspecified +} diff --git a/internal/media/processingemoji.go b/internal/media/processingemoji.go index 696b78ed3..89a1bcc91 100644 --- a/internal/media/processingemoji.go +++ b/internal/media/processingemoji.go @@ -154,7 +154,7 @@ func (p *ProcessingEmoji) store(ctx context.Context) error { // Pass input file through ffprobe to // parse further metadata information. - result, err := ffprobe(ctx, temppath) + result, err := probe(ctx, temppath) if err != nil && !isUnsupportedTypeErr(err) { return gtserror.Newf("ffprobe error: %w", err) } else if result == nil { diff --git a/internal/media/processingmedia.go b/internal/media/processingmedia.go index b89bbb41d..78c6c61a9 100644 --- a/internal/media/processingmedia.go +++ b/internal/media/processingmedia.go @@ -162,7 +162,7 @@ func (p *ProcessingMedia) store(ctx context.Context) error { // Pass input file through ffprobe to // parse further metadata information. - result, err := ffprobe(ctx, temppath) + result, err := probe(ctx, temppath) if err != nil && !isUnsupportedTypeErr(err) { return gtserror.Newf("ffprobe error: %w", err) } else if result == nil { |