The updateChunkOffsets() function in mp4qtchapterlist.cpp and
mp4chapterlist.cpp is duplicated code from mp4tag.cpp and needs
the patch from mp4tag.cpp too.
Changes made
mp4chapterlist.h
• Added (MP4::File*) overloads for read, write, remove
• Replaced broken class File; forward declaration with #include "mp4file.h" (fixed a subtle C++ name-resolution linker bug where Atoms(File*) resolved to MP4::File* instead of TagLib::File*)
mp4chapterlist.cpp
• Refactored: path-based overloads are now thin wrappers that delegate to file-based overloads
• File-based overloads construct Atoms locally — no Atoms* in the public API
• Removed chplHeaderSize = 9 constant; replaced the minimum-size guard in parseChplData with a correct 5-byte check (the old constant was version-1 specific and would reject valid version-0 atoms)
mp4qtchapterlist.h
• Added (MP4::File*) overloads for read, write, remove
• Removed Atoms* parameters entirely from the public API
mp4qtchapterlist.cpp
• Same refactor: path-based overloads delegate; file-based overloads construct Atoms locally
• Added empty-chapter guard: write(MP4::File*, {}) delegates to remove(file) instead of writing a 0-sample chapter track
tests/test_mp4.cpp
• Added testChapterListFileAPI and testQTChapterListFileAPI — exercise the full write/read/remove cycle via the file-based API
• Updated test bodies to use the simplified (MP4::File*) API (no MP4::Atoms construction in test code)
QuickTime-style chapter tracks are the native chapter format for
Apple's ecosystem. They use a disabled text track (hdlr type "text")
referenced by a chap track-reference in the audio track's tref box.
This format is recognized by QuickTime, iTunes/Music, Final Cut Pro,
Logic Pro, DaVinci Resolve, VLC, and most other MP4/M4A players. It
is also the format that AVFoundation reads natively via
AVAssetChapterMetadataGroup.
The implementation produces output that matches ffmpeg's chapter track
structure byte-for-byte: per-sample stts entries (required by
AVFoundation), encd atoms for UTF-8 text encoding, edts/elst edit
lists, gmhd with gmin+text media information, and disabled tkhd flags
(track_in_movie only).
Key behaviors:
- write() inserts tref + chapter trak as a single contiguous block,
then appends text samples in an mdat atom at EOF
- Handles non-zero first chapter times by prepending a dummy chapter
at time 0 (stripped on read)
- Overwrite support: removes existing chapter track before writing
- Preserves existing metadata tags and audio data integrity
- Uses timescale=1000 (milliseconds) for chapter track timing
7 new tests covering write/read round-trip, remove, overwrite, tag
preservation, empty file read, timestamp precision, and non-zero
first chapter handling.
Implement read/write/remove of Nero-style chapter markers (chpl atom)
in MP4 files. The chpl atom lives at moov/udta/chpl, storing up to 255
chapter entries with 100-nanosecond timestamps and UTF-8 titles.
Includes CppUnit tests covering round-trip read/write, remove, tag
preservation, and reading from files with no chapters.
Make MP4 AtomDataType descriptions visible in the generated documentation.
Convert the ID3v2 text frame listing into a table.
Convert the shorten `fileType()` documentation into a table.
Fix some typos.
Add link to specification in `EventType` for consistency with other headers.
* Shorten: Reject out-of-range k in getRiceGolombCode
k values outside [0, 31] cause undefined behavior: a left shift by 32
on int32_t (UB in C++) when bitsAvailable reaches 32 after a buffer
refill. Guard against this at the top of getRiceGolombCode and return
false (invalid file) for any k outside the valid range.
* Shorten: Reject out-of-range k in getRiceGolombCode
k values outside [0, 31] cause undefined behavior: a left shift by 32
on int32_t (UB in C++) when bitsAvailable reaches 32 after a buffer
refill. Guard against this at the top of getRiceGolombCode and return
false (invalid file) for any k outside the valid range.
This will fix a DoS with a crafted MP4 file causing too many offsets
to be written when updating the stco or co64 tables in MP4 files.
Credits for the discovery of this bug go to Yuen Ying Ng (Ruth)
(Cyber Security Researcher at PwC Hong Kong).
Concurrent calls to propertyKeyForName() and handlerTypeForName() (e.g.
via batchMap during import) could race on the isEmpty() guard used for
first-call lazy initialization.
Replace isEmpty() guards with std::call_once / std::once_flag so that
each map is initialized exactly once in a thread-safe manner. Using
call_once (rather than eager construction in the base class constructor)
preserves virtual dispatch, allowing ItemFactory subclasses to override
nameHandlerMap() and namePropertyMap() correctly.
Both property maps are initialized together in a single once_flag since
nameForPropertyKey is derived from namePropertyMap.
mpegheader.cpp: ADTS bitrate divided by 1024 (binary kilo) instead of
1000 (decimal kilo), causing ~2.4% underreporting for all AAC streams.
mp4properties.cpp: ESDS averageBitrate double-rounded via both +500 and
+0.5 before int cast, causing standard bitrates (128000, 192000, etc.)
to read 1 kbps too high.
Some encoders write a valid data chunk but with a slightly too-large
declared chunkSize, or place the data chunk beyond the declared RIFF
boundary. The previous behaviour called break, abandoning all remaining
chunks and making the file appear empty to taglib.
Lenient parsers (ffmpeg, QuickTime) handle this case by clamping the
chunk size to the bytes that actually remain in the file. Adopt the
same strategy: when chunkSize would exceed the file length, clamp it
and continue parsing rather than stopping early.
Read, write, and remove Broadcast Audio Extension (BEXT, EBU Tech 3285)
and iXML metadata chunks in WAV files. BEXT is widely used in broadcast
and professional audio for originator, description, time reference, and
loudness metadata. iXML is used by field recorders and DAWs for scene,
take, and track metadata.
MPEG::File::isSupported() scans for frame sync bytes that can appear
in other files, causing them to be misidentified as MP3.
This also includes a test with such a file.
When using for example
examples/tagwriter -C GENRE \
"name=GENRE,targetTypeValue=50,value=Soft Rock;name=GENRE,targetTypeValue=50,value=Classic Rock" \
path/to/file.mka
the GENRE key was included twice and tagreader displayed the two genre
tags twice.
A crafted file can have blockSamples set to 0 and a blockSize so big
that when adding 8 it overflows and offset is 0 so it goes back to the
same position and loops forever
When building for macOS < 10.14, the API for std::optional and
std::variant is restricted
error: 'value' is unavailable: introduced in macOS 10.14
error: 'get<..>' is unavailable: introduced in macOS 10.14
There was also an issue with Android armeabi-v7a where long is not
64 bit and a static assertion failed.
Make AttachedFile immutable. This is consistent with SimpleTag and
Chapter and avoids using attached files which do not have all required
attributes.
Provide methods to insert and remove a single simple tag, so that
they can be modified without setting all of them while still not
exposing internal lists to the API.
Use DATE_RECORDED instead of DATE_RELEASED for year() and the "DATE"
property. This is more consistent with other tag formats, e.g. for ID3v2
"TDRC" is used, which is the recording time.
A complex property can be set with
-C <complex-property-key> <key1=val1,key2=val2,...>
The second parameter can be set to "" to delete complex properties with the
given key. The set complex property values, a simple shorthand syntax can be
used. Multiple maps are separated by ';', values within a map are assigned
with key=value and separated by a ','. Types are automatically detected,
double quotes can be used to force a string. A ByteVector can be constructed
from the contents of a file with the path is given after "file://". There is
no escape, but hex codes are supported, e.g. "\x2C" to include a ',' and \x3B
to include a ';'.
Examples:
Set a GEOB frame in an ID3v2 tag:
examples/tagwriter -C GENERALOBJECT \
'data=file://file.bin,description=My description,fileName=file.bin,mimeType=application/octet-stream' \
file.mp3
Set an APIC frame in an ID3v2 tag (same as -p file.jpg 'My description'):
examples/tagwriter -C PICTURE \
'data=file://file.jpg,description=My description,pictureType=Front Cover,mimeType=image/jpeg' \
file.mp3
Set an attached file in a Matroska file:
examples/tagwriter -C file.bin \
'fileName=file.bin,data=file://file.bin,mimeType=application/octet-stream' \
file.mka
Set simple tag with target type in a Matroska file:
examples/tagwriter -C PART_NUMBER \
name=PART_NUMBER,targetTypeValue=20,value=2 file.mka
Set simple tag with binary value in a Matroska file:
examples/tagwriter -C BINARY \
name=BINARY,data=file://file.bin,targetTypeValue=60 file.mka
