[libcamera-devel] [PATCH v4 3/3] android: camera_device: Configure one stream for identical stream requests

[Hirokazu Honda]

An Android HAL client may request identical stream requests. It is
redundant that a native camera device produces a separate stream for
each of the identical requests.
Configure camera one stream configuration for the identical stream
requests.

Signed-off-by: Hirokazu Honda <hiroh at chromium.org>
Reviewed-by: Jacopo Mondi <jacopo at jmondi.org>
---
 src/android/camera_device.cpp | 28 +++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/src/android/camera_device.cpp b/src/android/camera_device.cpp
index 324b997f..51d5370e 100644
--- a/src/android/camera_device.cpp
+++ b/src/android/camera_device.cpp
@@ -618,12 +618,38 @@ int CameraDevice::configureStreams(camera3_stream_configuration_t *stream_list)
 			continue;
 		}
 
+		/*
+		 * Always add GRALLOC_USAGE_HW_CAMERA_WRITE to the usage on
+		 * ChromeOS because cros::CameraBufferManager imports the stream
+		 * buffer with the usage.
+		 */
+#if defined(OS_CHROMEOS)
+		stream->usage |= GRALLOC_USAGE_HW_CAMERA_WRITE;
+#endif
+
+		/*
+		 * If a CameraStream with the same size and format of the
+		 * current stream has already been requested, associate the two.
+		 */
+		auto iter = std::find_if(
+			streamConfigs.begin(), streamConfigs.end(),
+			[size, format](const Camera3StreamConfig &streamConfig) {
+				return streamConfig.config.size == size &&
+				       streamConfig.config.pixelFormat == format;
+			});
+		if (iter != streamConfigs.end()) {
+			/* Add usage to copy the buffer in streams[0] to stream. */
+			iter->streams[0].stream->usage |= GRALLOC_USAGE_SW_READ_OFTEN;
+			stream->usage |= GRALLOC_USAGE_SW_WRITE_OFTEN;
+			iter->streams.push_back({ stream, CameraStream::Type::Mapped });
+			continue;
+		}
+
 		Camera3StreamConfig streamConfig;
 		streamConfig.streams = { { stream, CameraStream::Type::Direct } };
 		streamConfig.config.size = size;
 		streamConfig.config.pixelFormat = format;
 		streamConfigs.push_back(std::move(streamConfig));
-
 		/* This stream will be produced by hardware. */
 		stream->usage |= GRALLOC_USAGE_HW_CAMERA_WRITE;
 	}
-- 
2.33.0.259.gc128427fd7-goog