[Bug 59517] New: IWICFormatConverter does not support BlackWhite as destination pixel format

[WineHQ Bugzilla]

http://bugs.winehq.org/show_bug.cgi?id=59517

            Bug ID: 59517
           Summary: IWICFormatConverter does not support BlackWhite as
                    destination pixel format
           Product: Wine
           Version: 11.4
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: windowscodecs
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 80541
  --> http://bugs.winehq.org/attachment.cgi?id=80541
test program

IWICFormatConverter::Initialize() returns WINCODEC_ERR_UNSUPPORTEDOPERATION
(0x88982F80) when GUID_WICPixelFormatBlackWhite is used as the destination
pixel format. On Windows, this conversion succeeds for all source formats.

This breaks .NET WPF applications that use System.Windows.Media.Imaging.
FormatConvertedBitmap with PixelFormats.BlackWhite. The WPF imaging
pipeline calls IWICFormatConverter internally, and the CLR maps the COM
error to System.NotSupportedException ("The operation is not supported").

Steps to reproduce:

1. Create a 1bpp indexed BMP image (e.g., 8x8 checkerboard)
2. Load it via WPF BitmapImage (PixelFormat = Indexed1)
3. Create a FormatConvertedBitmap with DestinationFormat = BlackWhite
4. Call EndInit() on the FormatConvertedBitmap

Expected: EndInit() succeeds, CopyPixels() returns valid 1bpp BlackWhite data
Actual:   EndInit() throws NotSupportedException (HRESULT 0x88982F80)

Verified on:
- Wine 11.4 (CachyOS/Arch, x86_64): FAIL - Tests 2+3 fail
- Windows 11: PASS - all 4 tests pass

Reproducer:

The attached wic_format_test.cs is a minimal C# test program that creates
an 8x8 1bpp BMP entirely in memory (no external files needed) and runs
four tests:

  Test 1: Load 1bpp BMP via BitmapImage            → PASS (Wine + Windows)
  Test 2: FormatConvertedBitmap → BlackWhite       → FAIL on Wine, PASS on
Windows
  Test 3: CopyPixels on converted bitmap           → FAIL on Wine, PASS on
Windows
  Test 4: FormatConvertedBitmap → Bgra32 (control) → PASS (Wine + Windows)

Compile (Wine or Windows, .NET 4.x):
  csc.exe /r:PresentationCore.dll /r:WindowsBase.dll /r:System.Xaml.dll \
          /target:exe /out:wic_format_test.exe wic_format_test.cs

Run:
  wine wic_format_test.exe
  (or on Windows: wic_format_test.exe)

Output is written to both console and wic_format_test.exe.log.txt.

Root cause:

In dlls/windowscodecs/converter.c, the supported_formats[] table entry for
format_BlackWhite has NULL as the conversion function pointer:

    {format_BlackWhite, &GUID_WICPixelFormatBlackWhite, NULL},

This means no pixel format can be converted TO BlackWhite. Conversions FROM
BlackWhite to other formats (e.g., 24bpp BGR, 8bpp Indexed) already work
because those destination formats have their own copypixels_to_*() functions
that handle format_BlackWhite as a source.

A fix with Wine conformance tests will be submitted as a merge request.

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