A CLI utility that converts one or more Canon RAW files to JPEG|TIFF by applying a DPP4 recipe (.dr4), using the Canon DPP4 engine installed on the machine — without opening the graphical interface.

All RAW files are added to a single DSFBatchScript and processed in one Execute() call, exactly as DPP4Batch.exe does internally:

DSFRecipe.Create() + recipe.ReadFileData(.dr4)
    ↓
DSFBatchScript.Create()
for each RAW file:
    script.AddFile(raw, jpg, DppImageType.Jpeg, recipe)
script.SetJpegQuality(quality)
script.SaveScriptFile(tempPath)
    ↓
DSFBatchProcess.Create(tempPath)
process.Execute()              <- all files in a single engine run
    ↓
DppMWare.dll  ←  native Canon engine performing the actual work

The process is WinExe with an STA thread and a WinForms message pump, required because DppMWare.dll uses COM STA internally.

• Windows 10 x64
• Canon DPP4 installed (default: C:\Program Files\Canon\Digital Photo Professional 4\)
• .NET Framework 4.7.1
• Visual Studio 2019+ or MSBuild Tools (to compile)

Copy these DPP4 dlls (DapCommon.dll, DapServiceFramework.dll, DapStrings.dll) from the DPP4 installation folder to the src/lib folder of this project. Open src\dpp4cli.csproj in Visual Studio, select Release | x64 and build. Or from the command line:

msbuild src\dpp4cli.csproj /p:Configuration=Release /p:Platform=x64

The executable is generated in src\bin\Release\dpp4cli.exe.

The three Canon managed DLLs (DapServiceFramework.dll, DapCommon.dll, DapStrings.dll) are stored in src\lib\ and are automatically copied next to the exe at every build. The native engine (DppMWare.dll and its dependencies) is loaded at runtime from the DPP4 installation folder — no recompile needed if DPP4 is reinstalled to a different location; just update dpp4cli.config.

Create (or edit) dpp4cli.config in the same folder as dpp4cli.exe:

# dpp4cli.config
# Path to the Canon DPP4 installation folder.
dpp4dir=C:\Program Files\Canon\Digital Photo Professional 4

This file is copied automatically to the output folder at build time.

dpp4cli --recipe <file.dr4> --outdir <folder> [options] file1.CR3 file2.CR3 ...

:: Single file
dpp4cli --recipe portrait.dr4 --outdir C:\export IMG_001.CR3

:: Multiple files
dpp4cli --recipe portrait.dr4 --outdir C:\export IMG_001.CR3 IMG_002.CR3 IMG_003.CR3

:: With suffix and quality
dpp4cli --recipe params.dr4 --outdir C:\export --suffix _edit --quality 95 IMG_001.CR3 IMG_002.CR3

:: PowerShell — convert all CR3 files in a folder
dpp4cli --recipe params.dr4 --outdir C:\export (Get-Item C:\raw\*.CR3)

:: cmd.exe — using a for loop
for %f in (C:\raw\*.CR3) do dpp4cli --recipe params.dr4 --outdir C:\export %f

For each input file <name>.<ext> the output will be <outdir>\<name><suffix>.jpg.

Per-file results are always printed to stdout regardless of --verbose, so you can detect partial failures even in non-verbose mode.

1. Open DPP4 and adjust the development parameters on any image.
2. Edit → Save recipe to file (Ctrl+Shift+C).
3. Save the .dr4 file.

The same recipe can be applied to any number of compatible RAW files.

Update dpp4dir in dpp4cli.config or use --dpp4dir <path>.

DPP4 is not installed or the DLL cannot be found. Verify that DapServiceFramework.dll exists in the configured DPP4 folder.

The RAW format is not supported by the installed DPP4 version, or the file is corrupt. Try opening it directly in DPP4 to confirm.

File format not supported. Only Canon RAW formats recognised by your DPP4 version are valid inputs.

Permission denied on the output folder. Check write permissions.

The default timeout is 5 + 2 × N minutes (where N is the number of files). For very large batches on slow machines this may not be enough; you can increase ConversionTimeout in Converter.cs.