Bugfix: CR3 detection

CR3 uses HEIF container, and is now properly detected as RAW and not HEIF Merge PR #310 by https://github.com/qbnu
sylikc · Jun 19, 2024 · dc058fa · dc058fa
2 parents a189456 + a587ecf
commit dc058fa
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Showing 2 changed files with 24 additions and 19 deletions.
diff --git a/src/JPEGView/Helpers.cpp b/src/JPEGView/Helpers.cpp
@@ -767,7 +767,7 @@ EImageFormat GetImageFormat(LPCTSTR sFileName) {
  return IF_JXL;
  } else if (_tcsicmp(sEnding, _T("AVIF")) == 0) {
  return IF_AVIF;
- } else if (_tcsicmp(sEnding, _T("HEIF")) == 0 || _tcsicmp(sEnding, _T("HEIC")) == 0) {
+ } else if (_tcsicmp(sEnding, _T("HEIF")) == 0 || _tcsicmp(sEnding, _T("HEIC")) == 0 || _tcsicmp(sEnding, _T("HIF")) == 0) {
  return IF_HEIF;
  } else if (_tcsicmp(sEnding, _T("TGA")) == 0) {
  return IF_TGA;

diff --git a/src/JPEGView/ImageLoadThread.cpp b/src/JPEGView/ImageLoadThread.cpp
@@ -62,36 +62,41 @@ static EImageFormat GetImageFormat(LPCTSTR sFileName) {
  } else if ((header[0] == 0xff && header[1] == 0x0a) ||
  memcmp(header, "\x00\x00\x00\x0cJXL\x20\x0d\x0a\x87\x0a", 12) == 0) {
  return IF_JXL;
-
- // Unfortunately, TIFF detection by header bytes is not reliable
- // A few RAW image formats use TIFF as the container
- // ex: CR2 - http://lclevy.free.fr/cr2/#key_info
- // ex: DNG - https://www.adobe.com/creativecloud/file-types/image/raw/dng-file.html#dng
- //
- // JPEGView will fail to open these files if the following code is used
- //
- //} else if ((header[0] == 0x49 && header[1] == 0x49 && header[2] == 0x2a && header[3] == 0x00) ||
- // (header[0] == 0x4d && header[1] == 0x4d && header[2] == 0x00 && header[3] == 0x2a)) {
- // return IF_TIFF;
-
- } else if (header[0] == 0x00 && header[1] == 0x00 && header[2] == 0x00 && memcmp(header+4, "ftyp", 4) == 0) {
+ } else if (!memcmp(header+4, "ftyp", 4)) {
  // https://github.com/strukturag/libheif/issues/83
  // https://github.com/strukturag/libheif/blob/ce1e4586b6222588c5afcd60c7ba9caa86bcc58c/libheif/heif.h#L602-L805
 
+ // AV1: avif, avis
+ if (!memcmp(header+8, "avi", 3))
+ return IF_AVIF;
  // H265: heic, heix, hevc, hevx, heim, heis, hevm, hevs
- if (header[8] == 'h' && header[9] == 'e')
+ if (!memcmp(header+8, "hei", 3) || !memcmp(header+8, "hev", 3))
  return IF_HEIF;
- // AV1: avif, avis
- // Unspecified encoding: mif1, mif2, msf1, miaf, 1pic
- return IF_AVIF; // try libavif, fallback to libheif
+ // Canon CR3
+ if (!memcmp(header+8, "crx ", 4))
+  return IF_CameraRAW;
  } else if (header[0] == 'q' && header[1] == 'o' && header[2] == 'i' && header[3] == 'f') {
  return IF_QOI;
  } else if (header[0] == '8' && header[1] == 'B' && header[2] == 'P' && header[3] == 'S') {
  return IF_PSD;
  }
 
  // default fallback if no matches based on magic bytes
- return Helpers::GetImageFormat(sFileName);
+ EImageFormat eImageFormat = Helpers::GetImageFormat(sFileName);
+
+ if (eImageFormat != IF_Unknown) {
+ return eImageFormat;
+ } else if (!memcmp(header+4, "ftyp", 4)) {
+ // Unspecified encoding (possibly AVIF or HEIF): mif1, mif2, msf1, miaf, 1pic
+ return IF_AVIF;
+ } else if (!memcmp(header, "II*\0", 4) || !memcmp(header, "MM\0*", 4)) {
+ // Must be checked after file extension to avoid classifying RAW as TIFF
+ // A few RAW image formats use TIFF as the container
+ // ex: CR2 - http://lclevy.free.fr/cr2/#key_info
+ // ex: DNG - https://www.adobe.com/creativecloud/file-types/image/raw/dng-file.html#dng
+ return IF_TIFF;
+ }
+ return IF_Unknown;
 }
 
 static EImageFormat GetBitmapFormat(Gdiplus::Bitmap * pBitmap) {