[libcamera-devel] [PATCH 4/5] thumbnailer: Change the type of thumbnail to MappedBuffer

[Hirokazu Honda]

Thumbnailer uses the std::vector<unsigned char> for the created
thumbnail. The created thumbnail is NV12. It should rather be
deal with MappedBuffer interface.

Signed-off-by: Hirokazu Honda <hiroh at chromium.org>
---
 src/android/jpeg/post_processor_jpeg.cpp | 12 ++++++++----
 src/android/jpeg/thumbnailer.cpp         | 12 +++++++-----
 src/android/jpeg/thumbnailer.h           |  6 +++++-
 3 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/src/android/jpeg/post_processor_jpeg.cpp b/src/android/jpeg/post_processor_jpeg.cpp
index 3160a784..6eefce0f 100644
--- a/src/android/jpeg/post_processor_jpeg.cpp
+++ b/src/android/jpeg/post_processor_jpeg.cpp
@@ -56,7 +56,7 @@ void PostProcessorJpeg::generateThumbnail(const FrameBuffer &source,
 					  std::vector<unsigned char> *thumbnail)
 {
 	/* Stores the raw scaled-down thumbnail bytes. */
-	std::vector<unsigned char> rawThumbnail;
+	std::unique_ptr<MappedBuffer> rawThumbnail;
 
 	thumbnailer_.createThumbnail(source, targetSize, &rawThumbnail);
 
@@ -65,14 +65,18 @@ void PostProcessorJpeg::generateThumbnail(const FrameBuffer &source,
 	thCfg.pixelFormat = thumbnailer_.pixelFormat();
 	int ret = thumbnailEncoder_.configure(thCfg);
 
-	if (!rawThumbnail.empty() && !ret) {
+	if (!rawThumbnail && !ret) {
 		/*
 		 * \todo Avoid value-initialization of all elements of the
 		 * vector.
 		 */
-		thumbnail->resize(rawThumbnail.size());
+		size_t bufferSize = 0;
+		for (const auto &plane : rawThumbnail->planes())
+			bufferSize += plane.size();
+		thumbnail->resize(bufferSize);
 
-		int jpeg_size = thumbnailEncoder_.encode(rawThumbnail,
+		libcamera::Span rawThumbnailData(rawThumbnail->planes()[0].data(), bufferSize);
+		int jpeg_size = thumbnailEncoder_.encode(rawThumbnailData,
 							 *thumbnail, {}, quality);
 		thumbnail->resize(jpeg_size);
 
diff --git a/src/android/jpeg/thumbnailer.cpp b/src/android/jpeg/thumbnailer.cpp
index fe2c4969..f88cda10 100644
--- a/src/android/jpeg/thumbnailer.cpp
+++ b/src/android/jpeg/thumbnailer.cpp
@@ -39,7 +39,7 @@ void Thumbnailer::configure(const Size &sourceSize, PixelFormat pixelFormat)
 
 void Thumbnailer::createThumbnail(const FrameBuffer &source,
 				  const Size &targetSize,
-				  std::vector<unsigned char> *destination)
+				  std::unique_ptr<libcamera::MappedBuffer> *dest)
 {
 	MappedFrameBuffer frame(&source, MappedFrameBuffer::MapFlag::Read);
 	if (!frame.isValid()) {
@@ -67,10 +67,12 @@ void Thumbnailer::createThumbnail(const FrameBuffer &source,
 	unsigned char *srcCb, *srcCr;
 	unsigned char *dstY, *srcY;
 
-	size_t dstSize = (th * tw) + ((th / 2) * tw);
-	destination->resize(dstSize);
-	unsigned char *dst = destination->data();
-	unsigned char *dstC = dst + th * tw;
+	*dest = std::make_unique<MappedVectorBuffer>(
+		std::vector<std::vector<uint8_t>>{
+			std::vector<uint8_t>(th * tw),
+			std::vector<uint8_t>((th / 2) * tw) });
+	unsigned char *dst = (*dest)->planes()[0].data();
+	unsigned char *dstC = (*dest)->planes()[1].data();
 
 	for (unsigned int y = 0; y < th; y += 2) {
 		unsigned int sourceY = (sh * y + th / 2) / th;
diff --git a/src/android/jpeg/thumbnailer.h b/src/android/jpeg/thumbnailer.h
index 4d086c49..8b007f1e 100644
--- a/src/android/jpeg/thumbnailer.h
+++ b/src/android/jpeg/thumbnailer.h
@@ -7,11 +7,15 @@
 #ifndef __ANDROID_JPEG_THUMBNAILER_H__
 #define __ANDROID_JPEG_THUMBNAILER_H__
 
+#include <memory>
+
 #include <libcamera/framebuffer.h>
 #include <libcamera/geometry.h>
 
 #include "libcamera/internal/formats.h"
 
+#include "libcamera/internal/mapped_framebuffer.h"
+
 class Thumbnailer
 {
 public:
@@ -21,7 +25,7 @@ public:
 		       libcamera::PixelFormat pixelFormat);
 	void createThumbnail(const libcamera::FrameBuffer &source,
 			     const libcamera::Size &targetSize,
-			     std::vector<unsigned char> *dest);
+			     std::unique_ptr<libcamera::MappedBuffer> *dest);
 	const libcamera::PixelFormat &pixelFormat() const { return pixelFormat_; }
 
 private:
-- 
2.33.0.259.gc128427fd7-goog