tests/Makefile: properly use cornersync mode from Makefile variable

[swesterfeld]

No description provided.

[gemini-code-assist]

Summary of Changes

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This pull request introduces a change to the tests/Makefile to allow the cornersync mode, used by the imagewmark get command, to be controlled by a Makefile variable. This modification improves the configurability and adaptability of the test suite, enabling easier adjustments to cornersync settings without direct code changes, thereby streamlining test execution and maintenance.

Highlights

• Makefile Update: The tests/Makefile has been modified to enhance test configuration.
• Dynamic Cornersync Mode: The imagewmark get command within the Makefile now dynamically uses the CORNERSYNC_MODE variable.
• Improved Test Flexibility: This change allows the cornersync mode to be configured externally via a Makefile variable, increasing the flexibility of the test suite.

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[greptile-apps]

Greptile Overview

Greptile Summary

This PR fixes a configuration bug in the test harness where the watermark extraction command was ignoring the CORNERSYNC_MODE variable. The Makefile already defined this variable (defaulting to 'auto') and used it to conditionally exclude rotation/crop attacks when set to 'on', but the imagewmark get command wasn't receiving the --cornersync flag. The fix adds --cornersync $(CORNERSYNC_MODE) to the extraction command on line 125, ensuring the test configuration is honored end-to-end. This aligns the extraction behavior with the embedding and attack-selection logic that already respected the mode setting, making the test framework consistent when users want to validate cornersync-specific watermarking scenarios.

Important Files Changed

Filename	Score	Overview
tests/Makefile	5/5	Added --cornersync $(CORNERSYNC_MODE) flag to extraction command to honor test configuration

Confidence score: 5/5

• This PR is safe to merge with minimal risk
• Score reflects a targeted bug fix that adds a missing configuration flag to match existing infrastructure; the change is isolated to the test harness and ensures consistency with pre-existing Makefile variables and conditional logic
• No files require special attention

Sequence Diagram

sequenceDiagram
    participant User
    participant Make
    participant wmtool.py
    participant imagewmark
    participant Extract

    User->>Make: "make all"
    Make->>Make: "check-nproc (validate job count)"
    
    Note over Make: Create/link input images
    Make->>Make: "create inputs/ directory"
    
    Note over Make: Embed watermarks
    loop For each input image
        Make->>imagewmark: "add --test-key <input> <output> <WATERMARK>"
        imagewmark-->>Make: "watermarked image in wmarked/"
    end
    
    Note over Make: Generate attack images
    loop For each attack type
        Make->>wmtool.py: "--seed <SEED> --attack <params> <input> <output>"
        wmtool.py-->>Make: "attacked image in attack/"
    end
    
    Note over Make: Extract watermarks (FIXED)
    loop For each attack image
        Make->>imagewmark: "get --test-key --expect <WATERMARK> --cornersync <CORNERSYNC_MODE> <image> --json"
        imagewmark-->>Make: "extraction result JSON"
        
        alt extraction failed and WITHOUT_ORIGINAL=false
            Make->>imagewmark: "get --test-key --expect <WATERMARK> --original <original> --json"
            imagewmark-->>Make: "retry with alignment"
        end
        
        Make->>Extract: "save to extract/*.json"
    end
    
    Note over Make: Generate reports
    Make->>Extract: "collect all JSON results"
    Make->>Make: "report.py <WATERMARK>"
    Make-->>User: "report.html, report.pdf, flat.txt, fails.txt"

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[gemini-code-assist]

Code Review

This pull request updates the tests/Makefile to use the CORNERSYNC_MODE variable when calling imagewmark get. The change is a good improvement, but it's incomplete. The --cornersync flag is missing from the fallback command that runs when the initial watermark extraction fails. I've added a comment to point this out so it can be fixed for consistency.

[gemini-code-assist]

While adding --cornersync $(CORNERSYNC_MODE) here is correct, the same flag is missing from the fallback imagewmark get call on line 128. This leads to inconsistent behavior, as the CORNERSYNC_MODE will not be respected if the initial extraction fails. For consistent behavior, please also add --cornersync $(CORNERSYNC_MODE) to the command on line 128.

[tim-janik]

tests/Makefile: properly use cornersync mode from Makefile variable

Thanks for that.

What about the fallback case that uses the original image though?

extract.py currently contains this logic:

   if args.cornersync >= 1:
     sync_list = [ (window_size, True) for window_size in config.extract_window_size ]
   elif args.cornersync == 0:
     sync_list = [ (window_size, False) for window_size in config.extract_window_size ]
   else:  # args.cornersync < 0: auto
     if orig_J is None:            # blind decoding
       sync_list = [ (window_size, False) for window_size in config.extract_window_size ]
       sync_list.insert (1, (config.extract_window_size[0], True))
     else:                         # decode with aligned original
       sync_list = [ (config.extract_window_size[0], True) ]

Do you prefer to leave it as is and then also add the --cornersync mode argument in tests/Makefile to the fallback case?
Alternatively, we can move the if orig_J is not None case out of the --cornersync=auto case in extract.py and just ignore the cornersync argument if an original is given. Thoughts?