Merge pull request opencv#25647 from Kumataro:fix25646

imgcodecs: support IMWRITE_JPEG_LUMA/CHROMA_QUALITY with internal libjpeg-turbo opencv#25647

Close opencv#25646

- increase JPEG_LIB_VERSION for internal libjpeg-turbo from 62 to 70
- add log when using IMWRITE_JPEG_LUMA/CHROMA_QUALITY with JPEG_LIB_VERSION<70
- add document IMWRITE_JPEG_LUMA/CHROMA_QUALITY requests JPEG_LIB_VERSION >= 70

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
- [x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [x] The feature is well documented and sample code can be built with the project CMake

Author: Kumataro

3rdparty/libjpeg-turbo/CMakeLists.txt

@@ -134,7 +134,7 @@ if(WITH_ARITH_DEC)
   set(D_ARITH_CODING_SUPPORTED 1)
 endif()
 
-set(JPEG_LIB_VERSION 62)
+set(JPEG_LIB_VERSION 70)
 
 # OpenCV
 set(JPEG_LIB_VERSION "${VERSION}-${JPEG_LIB_VERSION}" PARENT_SCOPE)

modules/imgcodecs/include/opencv2/imgcodecs.hpp

@@ -87,8 +87,8 @@ enum ImwriteFlags {
        IMWRITE_JPEG_PROGRESSIVE    = 2,  //!< Enable JPEG features, 0 or 1, default is False.
        IMWRITE_JPEG_OPTIMIZE       = 3,  //!< Enable JPEG features, 0 or 1, default is False.
        IMWRITE_JPEG_RST_INTERVAL   = 4,  //!< JPEG restart interval, 0 - 65535, default is 0 - no restart.
-       IMWRITE_JPEG_LUMA_QUALITY   = 5,  //!< Separate luma quality level, 0 - 100, default is -1 - don't use.
-       IMWRITE_JPEG_CHROMA_QUALITY = 6,  //!< Separate chroma quality level, 0 - 100, default is -1 - don't use.
+       IMWRITE_JPEG_LUMA_QUALITY   = 5,  //!< Separate luma quality level, 0 - 100, default is -1 - don't use. If JPEG_LIB_VERSION < 70, Not supported.
+       IMWRITE_JPEG_CHROMA_QUALITY = 6,  //!< Separate chroma quality level, 0 - 100, default is -1 - don't use. If JPEG_LIB_VERSION < 70, Not supported.
        IMWRITE_JPEG_SAMPLING_FACTOR = 7, //!< For JPEG, set sampling factor. See cv::ImwriteJPEGSamplingFactorParams.
        IMWRITE_PNG_COMPRESSION     = 16, //!< For PNG, it can be the compression level from 0 to 9. A higher value means a smaller size and longer compression time. If specified, strategy is changed to IMWRITE_PNG_STRATEGY_DEFAULT (Z_DEFAULT_STRATEGY). Default value is 1 (best speed setting).
        IMWRITE_PNG_STRATEGY        = 17, //!< One of cv::ImwritePNGFlags, default is IMWRITE_PNG_STRATEGY_RLE.

modules/imgcodecs/src/grfmt_jpeg.cpp

@@ -783,9 +783,9 @@ bool JpegEncoder::write( const Mat& img, const std::vector<int>& params )
             cinfo.comp_info[1].h_samp_factor = 1;
         }
 
-#if JPEG_LIB_VERSION >= 70
         if (luma_quality >= 0 && chroma_quality >= 0)
         {
+#if JPEG_LIB_VERSION >= 70
             cinfo.q_scale_factor[0] = jpeg_quality_scaling(luma_quality);
             cinfo.q_scale_factor[1] = jpeg_quality_scaling(chroma_quality);
             if ( luma_quality != chroma_quality )
@@ -797,8 +797,11 @@ bool JpegEncoder::write( const Mat& img, const std::vector<int>& params )
                 cinfo.comp_info[1].h_samp_factor = 1;
             }
             jpeg_default_qtables( &cinfo, TRUE );
-        }
+#else
+            // See https://github.com/opencv/opencv/issues/25646
+            CV_LOG_ONCE_WARNING(NULL, cv::format("IMWRITE_JPEG_LUMA/CHROMA_QUALITY are not supported bacause JPEG_LIB_VERSION < 70."));
 #endif // #if JPEG_LIB_VERSION >= 70
+        }
 
         jpeg_start_compress( &cinfo, TRUE );
 

modules/imgcodecs/test/test_jpeg.cpp

@@ -7,6 +7,10 @@ namespace opencv_test { namespace {
 
 #ifdef HAVE_JPEG
 
+extern "C" {
+#include "jpeglib.h"
+}
+
 /**
  * Test for check whether reading exif orientation tag was processed successfully or not
  * The test info is the set of 8 images named testExifRotate_{1 to 8}.jpg
@@ -308,6 +312,64 @@ TEST(Imgcodecs_Jpeg, encode_subsamplingfactor_usersetting_invalid)
     }
 }
 
+//==================================================================================================
+// See https://github.com/opencv/opencv/issues/25646
+typedef testing::TestWithParam<std::tuple<int, int>> Imgcodecs_Jpeg_encode_withLumaChromaQuality;
+
+TEST_P(Imgcodecs_Jpeg_encode_withLumaChromaQuality, basic)
+{
+    const int luma   = get<0>(GetParam());
+    const int chroma = get<1>(GetParam());
+
+    cvtest::TS& ts = *cvtest::TS::ptr();
+    string fname = string(ts.get_data_path()) + "../cv/shared/lena.png";
+
+    cv::Mat src = imread(fname, cv::IMREAD_COLOR);
+    ASSERT_FALSE(src.empty());
+
+    std::vector<uint8_t> jpegNormal;
+    ASSERT_NO_THROW(cv::imencode(".jpg", src, jpegNormal));
+
+    std::vector<int> param;
+    param.push_back(IMWRITE_JPEG_LUMA_QUALITY);
+    param.push_back(luma);
+    param.push_back(IMWRITE_JPEG_CHROMA_QUALITY);
+    param.push_back(chroma);
+
+    std::vector<uint8_t> jpegCustom;
+    ASSERT_NO_THROW(cv::imencode(".jpg", src, jpegCustom, param));
+
+#if JPEG_LIB_VERSION >= 70
+    // For jpeg7+, we can support IMWRITE_JPEG_LUMA_QUALITY and IMWRITE_JPEG_CHROMA_QUALITY.
+    if( (luma == 95 /* Default Luma Quality */ ) && ( chroma == 95 /* Default Chroma Quality */))
+    {
+        EXPECT_EQ(jpegNormal, jpegCustom);
+    }
+    else
+    {
+        EXPECT_NE(jpegNormal, jpegCustom);
+    }
+#else
+    // For jpeg6-, we cannot support IMWRITE_JPEG_LUMA/CHROMA_QUALITY because jpeg_default_qtables() is missing.
+    // - IMWRITE_JPEG_LUMA_QUALITY updates internal parameter of IMWRITE_JPEG_QUALITY.
+    // - IMWRITE_JPEG_CHROMA_QUALITY updates nothing.
+    if( luma == 95 /* Default Jpeg Quality */ )
+    {
+        EXPECT_EQ(jpegNormal, jpegCustom);
+    }
+    else
+    {
+        EXPECT_NE(jpegNormal, jpegCustom);
+    }
+#endif
+}
+
+INSTANTIATE_TEST_CASE_P( /* nothing */,
+                        Imgcodecs_Jpeg_encode_withLumaChromaQuality,
+                        testing::Combine(
+                            testing::Values(70, 95, 100),    // IMWRITE_JPEG_LUMA_QUALITY
+                            testing::Values(70, 95, 100) )); // IMWRITE_JPEG_CHROMA_QUALITY
+
 #endif // HAVE_JPEG
 
 }} // namespace