mp4-manipulator is a tool for inspecting and manipulating mp4 and other ISO base media file format (BMFF) files.

mp4-manipulator uses the Bento4 library to parse BMFF files, and uses Qt to provide a GUI.

Usage

Files can be opened via the File menu, or by dragging and dropping them on the interface. Multiple files can be opened, each will be given a separate tab.

Opened files can be inspected via the tree interface.

File manipulation

Note, this area of functionality is a work in progress. Further functionality is planned.

When selecting an atom via the right click context menu, the following options are exposed:

Atoms can be dumped to a file.
Atoms can be removed from an file. This will reprocess the file using Bento4, and the result will be shown in the tab.

To save a file following mutation, use the save option in the File menu.

Build notes

Prior to building make sure Qt is on your path or set CMAKE_PREFIX_PATH env vars to cmake can find your Qt install. E.g. CMAKE_PREFIX_PATH=/c/Qt/6.0.0/msvc2019_64/.
Generate build files with cmake -B build
Build with cmake --build build/

Windows specific build

Copy qt dlls with windeployqt.exe (e.g. /c/Qt/6.0.0/msvc2019_64/bin/windeployqt.exe build/Debug/ replacing the Qt path based on where Qt is, and Debug with whatever kind of build you've performed).

Building on Windows with clang

Need visual studio env vars set for linker. Can do so by starting a commnad prompt and running something like "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat" then doing the config (in gitbash) via

CMAKE_PREFIX_PATH=/c/Qt/6.0.0/msvc2019_64/ /c/Program\ Files/CMake/bin/cmake -G Ninja -DCMAKE_MAKE_PROGRAM=/e/Patches/Ninja/ninja -DCMAKE_CXX_COMPILER=clang-cl -DCMAKE_EXPORT_COMPILE_COMMANDS=ON -B build

MacOS specific build

Package into an app using macdeployqt(e.g. macdeployqt build/mp4-manipulator.app).

Development

Style

Google style + east const (at time of writing not enforced by clang-format (https://bugs.llvm.org/show_bug.cgi?id=34220), so is on devs to manually do so).

Use smart pointers (e.g. unique_ptr) for ownership. Raw pointers are not owning, though bento4 and Qt complicated this with their own internal styles, so be mindful of that.

Clang-format

clang-format 12 is currently used for formatting in automation. The in tree .clang-format does what it can, with manual exceptions to style (hopefully) noted in this readme.

SingingTree / mp4-manipulator