JPEG/R: minor update for decoder.

Expose metadata for the decoder
Updata document
Rename "jpegr_metadata" to "jpegr_metadata_struct"

Bug: b/264715926
Test: jpegr_test

Change-Id: I6d97209453b2338996f5dc2aabfbdbe3e8a8c20c
diff --git a/libs/jpegrecoverymap/include/jpegrecoverymap/jpegr.h b/libs/jpegrecoverymap/include/jpegrecoverymap/jpegr.h
index 9b2dde7..e2023a6 100644
--- a/libs/jpegrecoverymap/include/jpegrecoverymap/jpegr.h
+++ b/libs/jpegrecoverymap/include/jpegrecoverymap/jpegr.h
@@ -91,7 +91,10 @@
     int length;
 };
 
-struct jpegr_metadata {
+/*
+ * Holds information for recovery map related metadata.
+ */
+struct jpegr_metadata_struct {
   // JPEG/R version
   uint32_t version;
   // Max Content Boost for the map
@@ -103,12 +106,14 @@
 typedef struct jpegr_uncompressed_struct* jr_uncompressed_ptr;
 typedef struct jpegr_compressed_struct* jr_compressed_ptr;
 typedef struct jpegr_exif_struct* jr_exif_ptr;
-typedef struct jpegr_metadata* jr_metadata_ptr;
+typedef struct jpegr_metadata_struct* jr_metadata_ptr;
 typedef struct jpegr_info_struct* jr_info_ptr;
 
 class JpegR {
 public:
     /*
+     * Experimental only
+     *
      * Encode API-0
      * Compress JPEGR image from 10-bit HDR YUV.
      *
@@ -199,21 +204,40 @@
      * Decode API
      * Decompress JPEGR image.
      *
-     * The output JPEGR image is in RGBA_1010102 data format if decoding to HDR.
-     * @param compressed_jpegr_image compressed JPEGR image
-     * @param dest destination of the uncompressed JPEGR image
-     * @param exif destination of the decoded EXIF metadata.
-     * @param output_format flag for setting output color format. if set to
-     *                      {@code JPEGR_OUTPUT_SDR}, decoder will only decode the primary image
-     *                      which is SDR. Default value is JPEGR_OUTPUT_HDR_LINEAR.
-     * @param recovery_map destination of the decoded recovery map.
+     * @param compressed_jpegr_image compressed JPEGR image.
+     * @param dest destination of the uncompressed JPEGR image.
+     * @param exif destination of the decoded EXIF metadata. The default value is NULL where the
+                   decoder will do nothing about it. If configured not NULL the decoder will write
+                   EXIF data into this structure. The format is defined in {@code jpegr_exif_struct}
+     * @param output_format flag for setting output color format. Its value configures the output
+                            color format. The default value is {@code JPEGR_OUTPUT_HDR_LINEAR}.
+                            ----------------------------------------------------------------------
+                            |   output_format          |    decoded color format to be written   |
+                            ----------------------------------------------------------------------
+                            |     JPEGR_OUTPUT_SDR     |                RGBA_8888                |
+                            ----------------------------------------------------------------------
+                            | JPEGR_OUTPUT_HDR_LINEAR  |        (default)RGBA_F16 linear         |
+                            ----------------------------------------------------------------------
+                            |   JPEGR_OUTPUT_HDR_PQ    |             RGBA_1010102 PQ             |
+                            ----------------------------------------------------------------------
+                            |   JPEGR_OUTPUT_HDR_HLG   |            RGBA_1010102 HLG             |
+                            ----------------------------------------------------------------------
+     * @param recovery_map destination of the decoded recovery map. The default value is NULL where
+                           the decoder will do nothing about it. If configured not NULL the decoder
+                           will write the decoded recovery_map data into this structure. The format
+                           is defined in {@code jpegr_uncompressed_struct}.
+     * @param metadata destination of the decoded metadata. The default value is NULL where the
+                       decoder will do nothing about it. If configured not NULL the decoder will
+                       write metadata into this structure. the format of metadata is defined in
+                       {@code jpegr_metadata}.
      * @return NO_ERROR if decoding succeeds, error code if error occurs.
      */
     status_t decodeJPEGR(jr_compressed_ptr compressed_jpegr_image,
                          jr_uncompressed_ptr dest,
                          jr_exif_ptr exif = nullptr,
                          jpegr_output_format output_format = JPEGR_OUTPUT_HDR_LINEAR,
-                         jr_uncompressed_ptr recovery_map = nullptr);
+                         jr_uncompressed_ptr recovery_map = nullptr,
+                         jr_metadata_ptr metadata = nullptr);
 
     /*
     * Gets Info from JPEGR file without decoding it.
diff --git a/libs/jpegrecoverymap/include/jpegrecoverymap/jpegrutils.h b/libs/jpegrecoverymap/include/jpegrecoverymap/jpegrutils.h
index a381743..dd06fa2 100644
--- a/libs/jpegrecoverymap/include/jpegrecoverymap/jpegrutils.h
+++ b/libs/jpegrecoverymap/include/jpegrecoverymap/jpegrutils.h
@@ -45,7 +45,7 @@
     #define Endian_SwapBE16(n) (n)
 #endif
 
-struct jpegr_metadata;
+struct jpegr_metadata_struct;
 /*
  * Mutable data structure. Holds information for metadata.
  */
@@ -87,7 +87,7 @@
  * @param metadata place to store HDR metadata values
  * @return true if metadata is successfully retrieved, false otherwise
 */
-bool getMetadataFromXMP(uint8_t* xmp_data, size_t xmp_size, jpegr_metadata* metadata);
+bool getMetadataFromXMP(uint8_t* xmp_data, size_t xmp_size, jpegr_metadata_struct* metadata);
 
 /*
  * This method generates XMP metadata for the primary image.
@@ -156,7 +156,7 @@
  * @param metadata JPEG/R metadata to encode as XMP
  * @return XMP metadata in type of string
  */
- std::string generateXmpForSecondaryImage(jpegr_metadata& metadata);
+ std::string generateXmpForSecondaryImage(jpegr_metadata_struct& metadata);
 }  // namespace android::jpegrecoverymap
 
 #endif //ANDROID_JPEGRECOVERYMAP_JPEGRUTILS_H
diff --git a/libs/jpegrecoverymap/jpegr.cpp b/libs/jpegrecoverymap/jpegr.cpp
index f8763c6..e197bf0 100644
--- a/libs/jpegrecoverymap/jpegr.cpp
+++ b/libs/jpegrecoverymap/jpegr.cpp
@@ -107,7 +107,7 @@
     return ERROR_JPEGR_INVALID_INPUT_TYPE;
   }
 
-  jpegr_metadata metadata;
+  jpegr_metadata_struct metadata;
   metadata.version = kJpegrVersion;
 
   jpegr_uncompressed_struct uncompressed_yuv_420_image;
@@ -176,7 +176,7 @@
     return ERROR_JPEGR_INVALID_INPUT_TYPE;
   }
 
-  jpegr_metadata metadata;
+  jpegr_metadata_struct metadata;
   metadata.version = kJpegrVersion;
 
   jpegr_uncompressed_struct map;
@@ -235,7 +235,7 @@
     return ERROR_JPEGR_INVALID_INPUT_TYPE;
   }
 
-  jpegr_metadata metadata;
+  jpegr_metadata_struct metadata;
   metadata.version = kJpegrVersion;
 
   jpegr_uncompressed_struct map;
@@ -288,7 +288,7 @@
     return ERROR_JPEGR_RESOLUTION_MISMATCH;
   }
 
-  jpegr_metadata metadata;
+  jpegr_metadata_struct metadata;
   metadata.version = kJpegrVersion;
 
   jpegr_uncompressed_struct map;
@@ -332,7 +332,8 @@
                             jr_uncompressed_ptr dest,
                             jr_exif_ptr exif,
                             jpegr_output_format output_format,
-                            jr_uncompressed_ptr recovery_map) {
+                            jr_uncompressed_ptr recovery_map,
+                            jr_metadata_ptr metadata) {
   if (compressed_jpegr_image == nullptr || dest == nullptr) {
     return ERROR_JPEGR_INVALID_NULL_PTR;
   }
@@ -387,6 +388,18 @@
     memcpy(recovery_map->data, recovery_map_decoder.getDecompressedImagePtr(), size);
   }
 
+  jpegr_metadata_struct jr_metadata;
+  if (!getMetadataFromXMP(static_cast<uint8_t*>(recovery_map_decoder.getXMPPtr()),
+                          recovery_map_decoder.getXMPSize(), &jr_metadata)) {
+    return ERROR_JPEGR_DECODE_ERROR;
+  }
+
+  if (metadata != nullptr) {
+      metadata->version = jr_metadata.version;
+      metadata->minContentBoost = jr_metadata.minContentBoost;
+      metadata->maxContentBoost = jr_metadata.maxContentBoost;
+  }
+
   if (output_format == JPEGR_OUTPUT_SDR) {
     return NO_ERROR;
   }
@@ -417,13 +430,8 @@
   uncompressed_yuv_420_image.width = jpeg_decoder.getDecompressedImageWidth();
   uncompressed_yuv_420_image.height = jpeg_decoder.getDecompressedImageHeight();
 
-  jpegr_metadata metadata;
-  if (!getMetadataFromXMP(static_cast<uint8_t*>(recovery_map_decoder.getXMPPtr()),
-                          recovery_map_decoder.getXMPSize(), &metadata)) {
-    return ERROR_JPEGR_DECODE_ERROR;
-  }
-
-  JPEGR_CHECK(applyRecoveryMap(&uncompressed_yuv_420_image, &map, &metadata, output_format, dest));
+  JPEGR_CHECK(applyRecoveryMap(&uncompressed_yuv_420_image, &map, &jr_metadata, output_format,
+                               dest));
   return NO_ERROR;
 }
 
diff --git a/libs/jpegrecoverymap/jpegrutils.cpp b/libs/jpegrecoverymap/jpegrutils.cpp
index 38b78ad..ff96447 100644
--- a/libs/jpegrecoverymap/jpegrutils.cpp
+++ b/libs/jpegrecoverymap/jpegrutils.cpp
@@ -253,7 +253,7 @@
 const string XMPXmlHandler::minContentBoostAttrName = kMapGainMapMin;
 const string XMPXmlHandler::maxContentBoostAttrName = kMapGainMapMax;
 
-bool getMetadataFromXMP(uint8_t* xmp_data, size_t xmp_size, jpegr_metadata* metadata) {
+bool getMetadataFromXMP(uint8_t* xmp_data, size_t xmp_size, jpegr_metadata_struct* metadata) {
     string nameSpace = "http://ns.adobe.com/xap/1.0/\0";
 
     if (xmp_size < nameSpace.size()+2) {
@@ -327,7 +327,7 @@
   return ss.str();
 }
 
-string generateXmpForSecondaryImage(jpegr_metadata& metadata) {
+string generateXmpForSecondaryImage(jpegr_metadata_struct& metadata) {
   const vector<string> kConDirSeq({kConDirectory, string("rdf:Seq")});
   const vector<string> kLiItem({string("rdf:li"), kConItem});
 
diff --git a/libs/jpegrecoverymap/tests/jpegr_test.cpp b/libs/jpegrecoverymap/tests/jpegr_test.cpp
index 0a7d20a..be4b972 100644
--- a/libs/jpegrecoverymap/tests/jpegr_test.cpp
+++ b/libs/jpegrecoverymap/tests/jpegr_test.cpp
@@ -174,7 +174,7 @@
 }
 
 TEST_F(JpegRTest, writeXmpThenRead) {
-  jpegr_metadata metadata_expected;
+  jpegr_metadata_struct metadata_expected;
   metadata_expected.maxContentBoost = 1.25;
   metadata_expected.minContentBoost = 0.75;
   const std::string nameSpace = "http://ns.adobe.com/xap/1.0/\0";
@@ -189,7 +189,7 @@
   xmpData.insert(xmpData.end(), reinterpret_cast<const uint8_t*>(xmp.c_str()),
                   reinterpret_cast<const uint8_t*>(xmp.c_str()) + xmp.size());
 
-  jpegr_metadata metadata_read;
+  jpegr_metadata_struct metadata_read;
   EXPECT_TRUE(getMetadataFromXMP(xmpData.data(), xmpData.size(), &metadata_read));
   ASSERT_EQ(metadata_expected.maxContentBoost, metadata_read.maxContentBoost);
   ASSERT_EQ(metadata_expected.minContentBoost, metadata_read.minContentBoost);
@@ -476,7 +476,7 @@
 
   JpegRBenchmark benchmark;
 
-  jpegr_metadata metadata = { .version = 1,
+  jpegr_metadata_struct metadata = { .version = 1,
                               .maxContentBoost = 8.0f,
                               .minContentBoost = 1.0f / 8.0f };
 
diff --git a/libs/jpegrecoverymap/tests/recoverymapmath_test.cpp b/libs/jpegrecoverymap/tests/recoverymapmath_test.cpp
index 6c61ff1..cf6a034 100644
--- a/libs/jpegrecoverymap/tests/recoverymapmath_test.cpp
+++ b/libs/jpegrecoverymap/tests/recoverymapmath_test.cpp
@@ -554,8 +554,8 @@
 
 TEST_F(RecoveryMapMathTest, applyRecoveryLUT) {
   for (int boost = 1; boost <= 10; boost++) {
-    jpegr_metadata metadata = { .maxContentBoost = static_cast<float>(boost),
-                                .minContentBoost = 1.0f / static_cast<float>(boost) };
+    jpegr_metadata_struct metadata = { .maxContentBoost = static_cast<float>(boost),
+                                       .minContentBoost = 1.0f / static_cast<float>(boost) };
     RecoveryLUT recoveryLUT(&metadata);
     for (int idx = 0; idx < kRecoveryFactorNumEntries; idx++) {
       float value = static_cast<float>(idx) / static_cast<float>(kRecoveryFactorNumEntries - 1);
@@ -573,8 +573,8 @@
   }
 
   for (int boost = 1; boost <= 10; boost++) {
-    jpegr_metadata metadata = { .maxContentBoost = static_cast<float>(boost),
-                                .minContentBoost = 1.0f };
+    jpegr_metadata_struct metadata = { .maxContentBoost = static_cast<float>(boost),
+                                       .minContentBoost = 1.0f };
     RecoveryLUT recoveryLUT(&metadata);
     for (int idx = 0; idx < kRecoveryFactorNumEntries; idx++) {
       float value = static_cast<float>(idx) / static_cast<float>(kRecoveryFactorNumEntries - 1);
@@ -592,8 +592,8 @@
   }
 
   for (int boost = 1; boost <= 10; boost++) {
-    jpegr_metadata metadata = { .maxContentBoost = static_cast<float>(boost),
-                                .minContentBoost = 1.0f / pow(static_cast<float>(boost),
+    jpegr_metadata_struct metadata = { .maxContentBoost = static_cast<float>(boost),
+                                       .minContentBoost = 1.0f / pow(static_cast<float>(boost),
                                                               1.0f / 3.0f) };
     RecoveryLUT recoveryLUT(&metadata);
     for (int idx = 0; idx < kRecoveryFactorNumEntries; idx++) {
@@ -659,8 +659,8 @@
 }
 
 TEST_F(RecoveryMapMathTest, EncodeRecovery) {
-  jpegr_metadata metadata = { .maxContentBoost = 4.0f,
-                              .minContentBoost = 1.0f / 4.0f };
+  jpegr_metadata_struct metadata = { .maxContentBoost = 4.0f,
+                                     .minContentBoost = 1.0f / 4.0f };
 
   EXPECT_EQ(encodeRecovery(0.0f, 0.0f, &metadata), 127);
   EXPECT_EQ(encodeRecovery(0.0f, 1.0f, &metadata), 127);
@@ -717,8 +717,8 @@
 }
 
 TEST_F(RecoveryMapMathTest, ApplyRecovery) {
-  jpegr_metadata metadata = { .maxContentBoost = 4.0f,
-                              .minContentBoost = 1.0f / 4.0f };
+  jpegr_metadata_struct metadata = { .maxContentBoost = 4.0f,
+                                     .minContentBoost = 1.0f / 4.0f };
 
   EXPECT_RGB_NEAR(applyRecovery(RgbBlack(), 0.0f, &metadata), RgbBlack());
   EXPECT_RGB_NEAR(applyRecovery(RgbBlack(), 0.5f, &metadata), RgbBlack());
@@ -981,8 +981,8 @@
 }
 
 TEST_F(RecoveryMapMathTest, ApplyMap) {
-  jpegr_metadata metadata = { .maxContentBoost = 8.0f,
-                              .minContentBoost = 1.0f / 8.0f };
+  jpegr_metadata_struct metadata = { .maxContentBoost = 8.0f,
+                                     .minContentBoost = 1.0f / 8.0f };
 
   EXPECT_RGB_EQ(Recover(YuvWhite(), 1.0f, &metadata),
                 RgbWhite() * 8.0f);