[libcamera-devel] [PATCH v4 2/2] android: Fix generation of thumbnail for EXIF data

[Umang Jain]

Generation of thumbnail is not occuring currently because
ANDROID_JPEG_THUMBNAIL_SIZE is not set for request metadata passed
to PostProcessorJpeg::process(). This is a regression introduced in
1264628d3c92("android: jpeg: Configure thumbnailer based on request
metadata").

The patch fixes this issue by setting ANDROID_JPEG_THUMBNAIL_SIZE in
the request metadata template populated by
CameraCapabilities::requestTemplatePreview(). The value for
ANDROID_JPEG_THUMBNAIL_SIZE is set to be the first non-zero size
reported by static metadata ANDROID_JPEG_AVAILABLE_THUMBNAIL_SIZES.

Fixes: 1264628d3c92("android: jpeg: Configure thumbnailer based on request metadata")
Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
Reviewed-by: Hirokazu Honda <hiroh at chromium.org>
---
 src/android/camera_capabilities.cpp | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/src/android/camera_capabilities.cpp b/src/android/camera_capabilities.cpp
index edeb6943..ed59ae1c 100644
--- a/src/android/camera_capabilities.cpp
+++ b/src/android/camera_capabilities.cpp
@@ -1347,7 +1347,7 @@ std::unique_ptr<CameraMetadata> CameraCapabilities::requestTemplatePreview() con
 	 * CameraMetadata is capable of resizing the container on the fly, if
 	 * adding a new entry will exceed its capacity.
 	 */
-	auto requestTemplate = std::make_unique<CameraMetadata>(21, 36);
+	auto requestTemplate = std::make_unique<CameraMetadata>(22, 38);
 	if (!requestTemplate->isValid()) {
 		return nullptr;
 	}
@@ -1368,6 +1368,25 @@ std::unique_ptr<CameraMetadata> CameraCapabilities::requestTemplatePreview() con
 	requestTemplate->addEntry(ANDROID_CONTROL_AE_TARGET_FPS_RANGE,
 				  entry.data.i32, 2);
 
+	/*
+	 * Get thumbnail sizes from static metadata and add the first non-zero
+	 * size to the template.
+	 */
+	found = staticMetadata_->getEntry(ANDROID_JPEG_AVAILABLE_THUMBNAIL_SIZES,
+					  &entry);
+	ASSERT(found && entry.count >= 4);
+	unsigned int j = 0;
+	while (j < entry.count / 2) {
+		if (entry.data.i32[j] == 0 || entry.data.i32[j + 1] == 0) {
+			j += 2;
+			continue;
+		}
+
+		requestTemplate->addEntry(ANDROID_JPEG_THUMBNAIL_SIZE,
+					  entry.data.i32 + j, 2);
+		break;
+	}
+
 	uint8_t aeMode = ANDROID_CONTROL_AE_MODE_ON;
 	requestTemplate->addEntry(ANDROID_CONTROL_AE_MODE, aeMode);
 
-- 
2.31.1