Fix rawspeed-cli ARW/CR2/PEF decoding (missing metadata pass)

.github/workflows/rawspeed-cli.yml

@@ -54,6 +54,7 @@ jobs:
           if ($null -eq $exe) {
             throw "rawspeed-cli.exe not found under build/"
           }
+
           $output = (& $exe.FullName 2>&1 | Out-String)
           $exitCode = $LASTEXITCODE
           "exe: $($exe.FullName)" | Add-Content $env:GITHUB_STEP_SUMMARY
@@ -63,6 +64,75 @@ jobs:
             throw "rawspeed-cli smoke test failed: exe=$($exe.FullName) exit=$exitCode output=[$output]"
           }
           Write-Output "smoke test ok: $($exe.FullName)"
+
+          $w = 8
+          $h = 8
+          $pixels = [System.IO.MemoryStream]::new()
+          for ($y = 0; $y -lt $h; $y++) {
+            for ($x = 0; $x -lt $w; $x++) {
+              $b = [BitConverter]::GetBytes([uint16](($y * $w + $x) * 500 + 1000))
+              $pixels.Write($b, 0, 2)
+            }
+          }
+          $pixels = $pixels.ToArray()
+          $make = [System.Text.Encoding]::ASCII.GetBytes("rawspeed`0")
+          $model = [System.Text.Encoding]::ASCII.GetBytes("test`0")
+          $ucm = [System.Text.Encoding]::ASCII.GetBytes("rawspeed test`0")
+          $entryCount = 16
+          $extOffset = 8 + (2 + $entryCount * 12 + 4)
+          $makeOff = $extOffset
+          $modelOff = $makeOff + $make.Length
+          $ucmOff = $modelOff + $model.Length
+          $pixelOff = $ucmOff + $ucm.Length
+          $ms = [System.IO.MemoryStream]::new()
+          $bw = [System.IO.BinaryWriter]::new($ms)
+          $bw.Write([byte[]]@(0x49, 0x49, 0x2A, 0x00))
+          $bw.Write([uint32]8)
+          $bw.Write([uint16]$entryCount)
+          foreach ($e in @(
+            @(254, 4, 1, 0), @(256, 4, 1, $w), @(257, 4, 1, $h),
+            @(258, 3, 1, 16), @(259, 3, 1, 1), @(262, 3, 1, 32803),
+            @(271, 2, $make.Length, $makeOff), @(272, 2, $model.Length, $modelOff),
+            @(273, 4, 1, $pixelOff), @(277, 3, 1, 1), @(278, 4, 1, $h),
+            @(279, 4, 1, $pixels.Length))) {
+            $bw.Write([uint16]$e[0]); $bw.Write([uint16]$e[1])
+            $bw.Write([uint32]$e[2]); $bw.Write([uint32]$e[3])
+          }
+          $bw.Write([uint16]33421); $bw.Write([uint16]3); $bw.Write([uint32]2)
+          $bw.Write([byte[]]@(2, 0, 2, 0))
+          $bw.Write([uint16]33422); $bw.Write([uint16]1); $bw.Write([uint32]4)
+          $bw.Write([byte[]]@(0, 1, 1, 2))
+          $bw.Write([uint16]50706); $bw.Write([uint16]1); $bw.Write([uint32]4)
+          $bw.Write([byte[]]@(1, 4, 0, 0))
+          $bw.Write([uint16]50708); $bw.Write([uint16]2)
+          $bw.Write([uint32]$ucm.Length); $bw.Write([uint32]$ucmOff)
+          $bw.Write([uint32]0)
+          $bw.Write($make)
+          $bw.Write($model)
+          $bw.Write($ucm)
+          $bw.Write($pixels)
+          $bw.Flush()
+          $dng = Join-Path $env:RUNNER_TEMP "tiny.dng"
+          [System.IO.File]::WriteAllBytes($dng, $ms.ToArray())
+
+          $ppm = Join-Path $env:RUNNER_TEMP "tiny.ppm"
+          & $exe.FullName $dng $ppm 2>&1 | Out-String | Write-Output
+          $decodeExit = $LASTEXITCODE
+          if ($decodeExit -ne 0) {
+            throw "rawspeed-cli decode smoke test failed: exit=$decodeExit"
+          }
+          $ppmBytes = [System.IO.File]::ReadAllBytes($ppm)
+          $expected = "P6`n$w $h`n65535`n"
+          $expectedBytes = [System.Text.Encoding]::ASCII.GetBytes($expected)
+          if ($ppmBytes.Length -ne ($expectedBytes.Length + $w * $h * 6)) {
+            throw "unexpected PPM size: $($ppmBytes.Length)"
+          }
+          for ($i = 0; $i -lt $expectedBytes.Length; $i++) {
+            if ($ppmBytes[$i] -ne $expectedBytes[$i]) {
+              throw "unexpected PPM header"
+            }
+          }
+          Write-Output "decode smoke test ok: $dng -> $ppm ($($ppmBytes.Length) bytes)"
           exit 0
 
       - name: Stage and checksum

docs/rawspeed-cli-v1.0.1-regression-report.md

@@ -0,0 +1,68 @@
+rawspeed-cli v1.0.1 regression report
+=====================================
+
+Symptom
+-------
+
+rawspeed-cli v1.0.1 fails on ARW/CR2/PEF inputs with::
+
+  rawspeed: unsupported CFA pattern
+  exit 1
+
+v1.0.0 decoded the same files.
+
+Root cause
+----------
+
+``main.cpp`` only calls ``decoder->decodeRaw()`` and never
+``decoder->decodeMetaData()``. For ARW/CR2/PEF the CFA pattern is set
+in the metadata pass, not in the raw pass:
+
+- ``ArwDecoder::decodeMetaDataInternal`` (ArwDecoder.cpp:501) calls
+  ``mRaw->cfa.setCFA(2x2, R, G, G, B)`` before consulting the camera
+  database; the same holds for ``Cr2Decoder`` and ``PefDecoder``.
+- ``render()`` then reads ``raw->cfa`` with its default size (0, 0)
+  and fails at the ``cfaSize != 2x2`` check.
+
+The old v1.0.0 CLI only worked because it unconditionally called
+``raw->cfa.setCFA(2x2, R,G,G,B)`` in ``render()``. That call looked
+like dead code and was removed during the clang-tidy cleanup - it was
+load-bearing.
+
+Fix (v1.0.2)
+------------
+
+1. After ``decodeRaw()``, call ``decoder->decodeMetaData(&meta)``.
+   ``cameras.xml`` is resolved like ``rawspeed-identify`` does
+   (``RS_CAMERAS_XML_PATH``, ``<bindir>/../share/darktable/rawspeed/
+   cameras.xml``, then ``RAWSPEED_SOURCE_DIR/data/cameras.xml`` for
+   standalone builds). If it cannot be found or parsed, an empty
+   ``CameraMetaData{}`` is used: ``ArwDecoder`` (and Cr2/Pef) set the
+   RGGB CFA before consulting the database, and with
+   ``failOnUnknown = false`` an unknown camera only logs a warning and
+   returns early, so decoding works without ``cameras.xml``. A failing
+   metadata pass is logged and skipped rather than aborting the
+   decode.
+2. ``render()`` is hardened: if the reported CFA size is smaller than
+   2x2, it defaults to RGGB instead of failing. Larger CFA patterns
+   (e.g. X-Trans) still fail as unsupported. The existing 4-Bayer
+   pattern mapping is kept - it is correct once the CFA is real.
+3. The publish workflow's smoke test now decodes a real image (a
+   synthetic 8x8 uncompressed CFA DNG generated in the runner) and
+   verifies the PPM output, instead of only checking the usage path
+   which cannot catch this class of regression.
+
+Verification
+------------
+
+- synthetic 8x8 CFA DNG decodes: exit 0, ``P6 8 8 65535``, 397 bytes;
+  8-bit variant: 203 bytes
+- usage path still exits 2 with usage text
+- clang-format 18.1.8 idempotent, clang -Weverything -Werror clean,
+  clang-tidy (CI check set) clean, MSVC Release build green
+
+AI note
+-------
+
+This report and the fix were prepared with AI assistance (opencode),
+per AGENTS.md disclosure rules.

src/utilities/rawspeed-cli/main.cpp

@@ -8,8 +8,10 @@
 #include <cstdint>
 #include <cstdio>
 #include <exception>
+#include <filesystem>
 #include <functional>
 #include <memory>
+#include <string>
 #include <string_view>
 #include <thread>
 #include <vector>
@@ -23,6 +25,27 @@ using rawspeed::CFAColor;
 
 namespace {
 
+std::string find_cameras_xml(const char* argv0) {
+#ifdef RS_CAMERAS_XML_PATH
+  if (std::filesystem::exists(RS_CAMERAS_XML_PATH))
+    return RS_CAMERAS_XML_PATH;
+#endif
+  const std::string self(argv0);
+  const std::size_t lastslash = self.find_last_of(R"(/\)");
+  const std::string bindir = lastslash == std::string::npos
+                                 ? std::string(".")
+                                 : self.substr(0, lastslash);
+  std::string camfile = bindir + "/../share/darktable/rawspeed/cameras.xml";
+  if (std::filesystem::exists(camfile))
+    return camfile;
+#ifdef RAWSPEED_STANDALONE_BUILD
+  camfile = std::string(RAWSPEED_SOURCE_DIR "/data/cameras.xml");
+  if (std::filesystem::exists(camfile))
+    return camfile;
+#endif
+  return {};
+}
+
 struct DemosaicJob {
   rawspeed::Array2DRef<uint16_t> mosaic;
   rawspeed::Array1DRef<uint16_t> rgb;
@@ -121,7 +144,11 @@ bool render(const rawspeed::RawImage& raw, std::vector<uint16_t>& rgbOut,
   }
 
   const auto cfaSize = raw->cfa.getSize();
-  if (cfaSize.x != 2 || cfaSize.y != 2) {
+  if (cfaSize.x < 2 || cfaSize.y < 2) {
+    raw->cfa.setCFA(rawspeed::iPoint2D(2, 2), CFAColor::RED, CFAColor::GREEN,
+                    CFAColor::GREEN, CFAColor::BLUE);
+  }
+  if (raw->cfa.getSize().x != 2 || raw->cfa.getSize().y != 2) {
     std::fprintf(stderr, "rawspeed: unsupported CFA pattern\n");
     return false;
   }
@@ -230,6 +257,27 @@ int main(int argc_, char** argv_) {
 
     rawspeed::RawImage raw = decoder->decodeRaw();
 
+    auto meta = std::make_unique<rawspeed::CameraMetaData>();
+#ifdef HAVE_PUGIXML
+    const std::string camfile = find_cameras_xml(argv(0));
+    if (!camfile.empty()) {
+      try {
+        meta = std::make_unique<rawspeed::CameraMetaData>(camfile.c_str());
+      } catch (const std::exception& e) {
+        std::fprintf(stderr,
+                     "rawspeed: cameras.xml unusable ('%s'), continuing "
+                     "without it\n",
+                     e.what());
+      }
+    }
+#endif
+    try {
+      decoder->decodeMetaData(meta.get());
+    } catch (const std::exception& e) {
+      std::fprintf(stderr, "rawspeed: metadata pass failed, continuing: %s\n",
+                   e.what());
+    }
+
     std::vector<uint16_t> rgb;
     uint32_t w = 0;
     uint32_t h = 0;