RafDecoder: read the aspect ratio dialed in on the camera

src/librawspeed/common/RawImage.h

@@ -106,6 +106,13 @@ class ImageMetaData final {
 
   // ISO speed. If known the value is set, otherwise it will be '0'.
   int isoSpeed = 0;
+
+  // The aspect ratio the camera was set to while shooting, as {width,
+  // height}, when the camera recorded one and left the raw data uncropped.
+  // Consumers are expected to center it on the image themselves; the crop
+  // the vendor describes is relative to the vendor's own output area, which
+  // is not necessarily the area we hand out.
+  Optional<std::array<int, 2>> cameraAspectRatio;
 };
 
 class RawImageData : public ErrorLog {

src/librawspeed/decoders/RafDecoder.cpp

@@ -292,6 +292,32 @@ void RafDecoder::decodeMetaDataInternal(const CameraMetaData* meta) {
     mRaw->whitePoint = implicit_cast<int>((1UL << bps) - 1UL);
   }
 
+  // The aspect ratio dialed in on the camera, kept in the same proprietary
+  // directory as the crop tags read by getDefaultCrop(). Stored as height
+  // then width, like the cropped size beside it. The raw data is left
+  // uncropped, so this is the only record of the framing chosen while
+  // shooting.
+  // getIFDWithTag() throws, and not every raf carries that directory
+  if (mRootIFD->hasEntryRecursive(TiffTag::FUJI_RAFDATA)) {
+    const TiffIFD* raw = mRootIFD->getIFDWithTag(TiffTag::FUJI_RAFDATA);
+    if (raw->hasEntry(TiffTag::FUJI_RAWIMAGEASPECTRATIO) &&
+        raw->hasEntry(TiffTag::FUJI_RAWIMAGECROPPEDSIZE)) {
+      const TiffEntry* ratio = raw->getEntry(TiffTag::FUJI_RAWIMAGEASPECTRATIO);
+      const TiffEntry* size = raw->getEntry(TiffTag::FUJI_RAWIMAGECROPPEDSIZE);
+      if (ratio->count == 2 && size->count == 2) {
+        const int height = ratio->getU16(0);
+        const int width = ratio->getU16(1);
+        const int fullHeight = size->getU16(0);
+        const int fullWidth = size->getU16(1);
+        // The tag is written whether or not a ratio was picked, so it is only
+        // of interest when it differs from the shape of the frame itself.
+        if (width > 0 && height > 0 && fullWidth > 0 && fullHeight > 0 &&
+            width * fullHeight != height * fullWidth)
+          mRaw->metadata.cameraAspectRatio = std::array<int, 2>{width, height};
+      }
+    }
+  }
+
   // This is where we'd normally call setMetaData but since we may still need
   // to rotate the image for SuperCCD cameras we do everything ourselves
   auto id = mRootIFD->getID();

src/librawspeed/parsers/FiffParser.cpp

@@ -110,6 +110,7 @@ void FiffParser::parseData() {
       case TiffTag::FUJI_RAWIMAGEFULLSIZE:
       case TiffTag::FUJI_RAWIMAGECROPTOPLEFT:
       case TiffTag::FUJI_RAWIMAGECROPPEDSIZE:
+      case TiffTag::FUJI_RAWIMAGEASPECTRATIO:
       case TiffTag::FUJIOLDWB:
         // also 0x121?
         type = TiffDataType::SHORT;

src/librawspeed/tiff/TiffTag.h

@@ -54,6 +54,7 @@ enum class TiffTag : uint16_t {
   FUJI_RAWIMAGECROPPEDSIZE = 0x0111,
   ORIENTATION = 0x0112,
   SAMPLESPERPIXEL = 0x0115,
+  FUJI_RAWIMAGEASPECTRATIO = 0x0115,
   ROWSPERSTRIP = 0x0116,
   STRIPBYTECOUNTS = 0x0117,
   XRESOLUTION = 0x011A,